[go: up one dir, main page]

WO2024215515A1 - Drug linkers and antibody conjugates thereof - Google Patents

Drug linkers and antibody conjugates thereof Download PDF

Info

Publication number
WO2024215515A1
WO2024215515A1 PCT/US2024/022683 US2024022683W WO2024215515A1 WO 2024215515 A1 WO2024215515 A1 WO 2024215515A1 US 2024022683 W US2024022683 W US 2024022683W WO 2024215515 A1 WO2024215515 A1 WO 2024215515A1
Authority
WO
WIPO (PCT)
Prior art keywords
alkylene
amino acid
independently
adc
seq
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/US2024/022683
Other languages
French (fr)
Inventor
Jianing Wang
Ji Young Kim
Sung Ju Moon
Mingchao KANG
Nickolas KNUDSEN
Sukumar Sakamuri
Feng Tian
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ambrx Inc
Original Assignee
Ambrx Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ambrx Inc filed Critical Ambrx Inc
Publication of WO2024215515A1 publication Critical patent/WO2024215515A1/en
Anticipated expiration legal-status Critical
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D491/00—Heterocyclic compounds containing in the condensed ring system both one or more rings having oxygen atoms as the only ring hetero atoms and one or more rings having nitrogen atoms as the only ring hetero atoms, not provided for by groups C07D451/00 - C07D459/00, C07D463/00, C07D477/00 or C07D489/00
    • C07D491/22—Heterocyclic compounds containing in the condensed ring system both one or more rings having oxygen atoms as the only ring hetero atoms and one or more rings having nitrogen atoms as the only ring hetero atoms, not provided for by groups C07D451/00 - C07D459/00, C07D463/00, C07D477/00 or C07D489/00 in which the condensed system contains four or more hetero rings
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6801—Drug-antibody or immunoglobulin conjugates defined by the pharmacologically or therapeutically active agent
    • A61K47/6803—Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates
    • A61K47/68037—Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates the drug being a camptothecin [CPT] or derivatives
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6835—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site
    • A61K47/6849—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site the antibody targeting a receptor, a cell surface antigen or a cell surface determinant
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6835—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site
    • A61K47/6851—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site the antibody targeting a determinant of a tumour cell
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6889—Conjugates wherein the antibody being the modifying agent and wherein the linker, binder or spacer confers particular properties to the conjugates, e.g. peptidic enzyme-labile linkers or acid-labile linkers, providing for an acid-labile immuno conjugate wherein the drug may be released from its antibody conjugated part in an acidic, e.g. tumoural or environment
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02—Phosphorus compounds
    • C07F9/547—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom
    • C07F9/6561—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom containing systems of two or more relevant hetero rings condensed among themselves or condensed with a common carbocyclic ring or ring system, with or without other non-condensed hetero rings
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/2875—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants against the NGF/TNF superfamily, e.g. CD70, CD95L, CD153, CD154
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/30—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/30—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells
    • C07K16/3069—Reproductive system, e.g. ovaria, uterus, testes, prostate
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/32—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against translation products of oncogenes
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/90—Immunoglobulins specific features characterized by (pharmaco)kinetic aspects or by stability of the immunoglobulin
    • C07K2317/92—Affinity (KD), association rate (Ka), dissociation rate (Kd) or EC50 value

Definitions

  • ADCs BACKGROUND Antibody-drug conjugates
  • ADCs are a potent class of therapeutic constructs advancing the field of cancer therapeutics by allowing targeted delivery of cytotoxic agents to target cells, such as cancer cells.
  • cytotoxic agents such as cancer cells.
  • ADCs include gemtuzumab ozogamicin for AML (subsequently withdrawn from the market), brentuximab vedotin for ALCL and Hodgkin lymphoma, and trastuzumab emtansine for HER2-positive metastatic breast cancer (Verma et al., N Engl J Med 367:1783-91, 2012; Bross et al., Clin Cancer Res 7:1490-96, 2001; Francisco et al., Blood 102:1458-65, 2003); and sacituzumab govitecan for metastatic triple negative breast cancer (TNBC) (Zaman et al., OncoTargets and Therapy 12: 1781-1790, 2019
  • ADCs face challenges due to lack of therapeutic index and toxicity.
  • the linker technology for attachment of the cytotoxic drug to an antibody impacts the stability of ADCs during the systemic circulation. Therefore, there is a need in the art to design improved linkers such as phosphate-based linkers and drug design for antibody conjugation.
  • the present disclosure provides phosphate-based linkers with tunable stability for intracellular delivery of drug conjugates.
  • the phosphate-based linkers have differentiated and tunable stability in blood versus an intracellular environment and can further include a self- immolating linker.
  • Antibody-drug conjugates that comprise these linkers are stable in circulation (plasma/blood) but reactive or cleavable in intracellular compartments, such as lysosomal compartments, making them useful for intracellular delivery, the rate being dependent on the structure of the tuning element.
  • the present invention provides novel ADCs comprising phosphate-based linkers for drug design and for antibody conjugation. WSGR Ref.
  • ADC antibody-drug conjugate
  • Drug has the following structure: each n is independently 1 or 2; p is 1, 2, 3, 4, 5, 6, 7 or 8; each Y is independently O, N(R w ) or CH 2 ; wherein each R w is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH 2 ) m , * CH 2 -O-(CH 2 ) m , * (CH 2 ) m -O-CH 2 , * C(O)-(CH 2 ) m , * NH-(CH 2 ) m , * (CH 2 ) m (OCH 2 CH 2 ) k , * NH-(CH 2 ) m (OCH 2 CH 2 ) k , C 3 -C 6 cyclic alkylene, * (OCH 2 CH 2 )
  • each L 2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, each q is independently 1, 2, 3, 4, 5 or 6, and each r is independently 1, 2, 3, 4, 5 or 6; or L2b
  • Drug has the following structure: WSGR Ref. No: 31362-826.601 wherein the wavy line denotes connection to Linker. In some embodiments, Drug has the following structure: wherein the wavy line denotes connection to Linker.
  • the present disclosure provides an antibody-drug conjugate (ADC) of Formula (V) or (VI): wherein: Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids; L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof.
  • the phosphate-based moiety is a pyrophosphate ester. In some other embodiments, the phosphate-based moiety is a diphosphonate. In some embodiments, L further comprises at least one additional moiety, wherein each of the at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, - C(O)-, -N(Rw)-, -S(O)0-2-, and an amino acid, and any combination thereof; wherein each Rw is independently H or C 1 -C 8 alkyl, wherein each nn is independently an integer from 1 to 100; optionally, each arylene is phenylene.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –, -O-, -C(O)-, and -N(R w )-, and any combination thereof; wherein each R w is independently H or C 1 -C 8 alkyl; and wherein each nn is independently an integer from 1 to 100. In some embodiments, each R w is independently H or methyl.
  • E comprises an amide, an ester, a thioester, a pyrrolidine-2,5-dione, an oxime, a 4,5-dihydro-1,2,3-triazole or a 1,4-dihydropyridazine, wherein the 4,5-dihydro-1,2,3- triazole or 1,4-dihydropyridazine is optionally fused to an 8-membered ring.
  • E is selected from the group consisting of: WSGR Ref.
  • each Rb is independently H or unsubstituted alkyl; each Rc is unsubstituted alkyl; each R f is independently H or unsubstituted alkyl, each s is independently 0, 1, 2, 3, 4, 5 or 6, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to L; and each wavy line denotes connection to Ab.
  • each Rb is independently H or unsubstituted C1-C6 alkyl
  • each Rc is unsubstituted C1-C6 alkyl
  • each Rf is independently H or unsubstituted C1-C6 alkyl.
  • E is: ; wherein R c is unsubstituted C 1 -C 6 alkyl. In some embodiments, R c is methyl.
  • L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each of the at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(Rw)- and an amino acid; and combinations thereof; wherein each Rw is independently H or C 1 -C 8 alkyl; and wherein each nn is independently an integer from 1 to 100; optionally, each R w is independently H or methyl.
  • each U is independently: .
  • L is selected from the group consisting of: WSGR Ref. No: 31362-826.601 wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection of L to (a) -N(H)- of Formula (V), or (b) -O- of Formula (VI); and each + denotes connection to E.
  • each alkylene when present, is independently –(CH 2 )–, –(CH 2 ) 2 – or –(CH 2 ) 3 –; each m, when present, is independently 1, 2 or 3; each n is independently 1, 2 or 3; and each q, when present, is independently 1, 2 or 3.
  • the ADC is an ADC of Formula (V): .
  • the ADC is an ADC of Formula (VI): WSGR Ref. No: 31362-826.601 .
  • d is 1, 2, 3 or 4.
  • Ab comprises one or more non-natural amino acids.
  • Ab is configured to bind to an antigen.
  • Ab is configured to bind to a tumor-associated antigen (TAA) or cancer antigen.
  • Ab binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c,
  • TAA tumor-associated
  • each of the one or more non-natural amino acids is independently selected from the group consisting of para-acetyl phenylalanine, 4-acetyl-L-phenylalanine (para- D-glucosaminyl)-L-asparagine, O-allyl-L-tyrosine, alpha-N-acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3- amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L-tyrosine, 3-amino-L-tyrosine, 4- azido-L-phenylalanine,
  • phenylalanine L-DOPA
  • 4-ethynyl-L-phenylalanine 2-fluoro-L-phenylalanine, 3-fluoro-L- phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl-beta-D-galactosaminyl)-L- serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L-phenylalanine, 4- isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O-mannopyranosyl-L- serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L-phenylalanine, 2-methoxy-
  • At least one of the one or more non-natural amino acids is para- acetyl-L-phenylalanine (pAF). In some embodiments, each of the one or more non-natural amino acids is the same. In some embodiments, each of the one or more non-natural amino acids is para- acetyl-L-phenylalanine (pAF). In some embodiments, drug to antibody ratio is about 1, about 2, about 3 or about 4. In some embodiments, Ab comprises a heavy chain having a heavy chain amino acid sequence, a light chain having a light chain amino acid sequence, or both. In some embodiments, the heavy chain comprises at least one of the one or more non-natural amino acids.
  • the light chain comprises at least one of the one or more non-natural amino acids.
  • Ab comprises two heavy chains, wherein each heavy chain comprises at least one of the one or more non-natural amino acids. In some embodiments, Ab comprises two light chains; optionally, wherein each light chain comprises at least one of the one or more non-natural amino acids. In some embodiments, the one or more non-natural amino acids is 1, 2, 3 or 4 non- natural amino acids. In some embodiments, Ab comprises two heavy chains and two light chains, wherein each heavy chain comprises one non-natural amino acid. In some embodiments, each light chain comprises one non-natural amino acid. In some embodiments, Ab is an anti-trophoblast antigen 2 antibody (anti-TROP2 Ab), antibody fragment or variant thereof.
  • anti-TROP2 Ab anti-trophoblast antigen 2 antibody
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 1 to 17.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain amino acid sequence is selected from the group consisting of SEQ ID NOs: 5 and 6.
  • the heavy chain has the amino acid sequence of SEQ ID NO: 5, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-TROP2 Ab, antibody fragment or variant thereof WSGR Ref.
  • No: 31362-826.601 comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17.
  • the light chain has the amino acid sequence of SEQ ID NO: 11, wherein one non- natural amino acid occupies position 121.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 4.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11.
  • each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime.
  • Ab is an anti-CD70 antibody (anti-CD70 Ab), antibody fragment or variant thereof.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 18 to 24.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 20, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 19. In some embodiments, wherein the light chain has the amino acid sequence of SEQ ID NO: 24, wherein one non-natural amino acid occupies position 121.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 20. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 19. In some embodiments, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 24. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, Ab is an anti-HER2 antibody (anti-HER2 Ab), antibody fragment or variant thereof.
  • pAF para-acetyl-L-phenylalanine
  • Ab is an anti-HER2 antibody (anti-HER2 Ab), antibody fragment or variant thereof.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 25 to 28.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 26, wherein WSGR Ref. No: 31362-826.601 one non-natural amino acid occupies Kabat position 114.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises a light chain.
  • the light chain has the amino acid sequence of SEQ ID NO: 27.
  • the light chain has the amino acid sequence of SEQ ID NO: 28, wherein one non-natural amino acid occupies position 121.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 26. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 27. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 28. In some embodiments, each non- natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, Ab is an anti-PSMA antibody (anti-PSMA Ab), antibody fragment or variant thereof.
  • anti-PSMA Ab anti-PSMA Ab
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 29 to 45.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 36, 38, 40, 42 and 44, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 37, 39, 41, 43 and 45.
  • the anti- PSMA Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 36.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises two light chains.
  • each light chain has the amino acid sequence of SEQ ID NO: 37.
  • each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime.
  • Ab is an anti-HER3 antibody (anti-HER3 Ab), antibody fragment or variant thereof.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 46 to 58.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 58, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 47 to 57.
  • WSGR Ref. No: 31362-826.601 the light chain has the amino acid sequence of SEQ ID NO: 47.
  • the light chain has the amino acid sequence of SEQ ID NO: 51, wherein one non-natural amino acid occupies position 121.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 47.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51.
  • each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime.
  • the ADC disclosed herein is an ADC of Formula (V): .
  • Ab is an anti-HER3 monoclonal antibody comprising two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58.
  • the ADC further comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51.
  • Ab is an anti-TROP2 monoclonal antibody comprising two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5.
  • the ADC further comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11.
  • the present disclosure provides a compound of Formula (VII) or (VIII): WSGR Ref.
  • L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety.
  • W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, - C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein R b is H or unsubstituted alkyl, R c is unsubstituted alkyl, and R d is H, unsubstituted alkyl or a carboxylic acid protecting group.
  • the phosphate- based moiety is a pyrophosphate ester or a diphosphonate.
  • L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, – (alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, and combinations thereof, wherein each R w is independently H or C 1 -C 8 alkyl; wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; optionally, arylene is phenylene.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(R w )-, and combinations thereof, wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10, and wherein each Rw is independently H or C1-C8 alkyl.
  • W is selected from the group consisting of: WSGR Ref.
  • the optionally substituted monocyclic or polycyclic group comprising the cyclooctyne is selected from the group consisting of:
  • W is –O–NH 2 .
  • L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid, and combinations thereof; wherein each R w is independently H or C 1 -C 8 alkyl; wherein each nn is independently an integer of from 1 to 100; optionally, wherein each Rw is independently H or methyl.
  • each U is independently: .
  • L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –, -O-, -C(O)- and - N(R w )-, and combinations thereof; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; optionally, each Rw is independently H or methyl.
  • WSGR Ref is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstit
  • each J is independently: ; each alkylene is independently selected from the group consisting of: –(CH 2 )–, –(CH 2 ) 2 –, –(CH 2 ) 3 –, –(CH 2 ) 4 –, –(CH 2 ) 5 –, –(CH 2 ) 6 –, –(CH 2 ) 7 –, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII).
  • each alkylene when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; and each nn is independently 1, 2 or 3.
  • L is selected from the group consisting of: WSGR Ref. No: 31362-826.601 wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII); and each + denotes connection to W.
  • i is 1.
  • the compound is a compound of Formula (VII): ; or a pharmaceutically acceptable salt thereof.
  • the compound has the following structure: WSGR Ref. No: 31362-826.601 or a pharmaceutically acceptable salt thereof.
  • the compound is a compound of Formula (VIII): ; or a pharmaceutically acceptable salt thereof.
  • the compound has the following structure: or a pharmaceutically acceptable salt thereof.
  • the present disclosure provides a pharmaceutical composition comprising an ADC of the present disclosure or a compound of the present disclosure, and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • the pharmaceutical composition further comprises a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid, or combination thereof.
  • WSGR Ref a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid, or combination thereof.
  • the present disclosure provides a method of treating or preventing a disease in a subject, the method comprising administering to the subject an effective amount of an ADC of the present disclosure, a compound of the present disclosure, or a pharmaceutical composition comprising an ADC or a compound of the present disclosure.
  • the method further comprises administering to the subject a therapeutically effective amount of an additional therapeutic agent.
  • the additional therapeutic agent is a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid or a combination thereof.
  • the present disclosure provides an anti-TROP2 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 1 to 17.
  • the present disclosure provides an ADC comprising an anti- TROP2 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 1 to 17.
  • the present disclosure provides an anti-CD70 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 18 to 24.
  • the present disclosure provides an ADC comprising an anti- CD70 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 18 to 24.
  • the present disclosure provides an anti-HER2 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 25 to 28.
  • the present disclosure provides an ADC comprising an anti- HER2 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 25 to 28.
  • the present disclosure provides an anti-PSMA antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 29 to 45.
  • the present disclosure provides an ADC comprising an anti- PSMA antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 29 to 45.
  • the present disclosure provides an ADC comprising an anti- HER2 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs:
  • the present disclosure provides an anti-HER3 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 46 to 58.
  • the present disclosure provides an ADC comprising an anti- HER3 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 46 to 58.
  • FIG.1 shows evaluation of in vitro cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line HCC1569.
  • FIG.2 shows evaluation of in vitro cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line A375.
  • FIG.3 shows evaluation of in vitro cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line HCC827.
  • FIG. 4 shows evaluation of cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line Calu-6.
  • FIGS. 5A, 5B, 5C and 5D show evaluation of in vitro cytotoxic activity of an anti-TROP2 ADC and unconjugated cytotoxin exatecan against the following cell lines: BxPC-3 (FIG. 5A); MDA-MB-468 (FIG.5B); HCC1806 (FIG.5C); and Calu-6 (FIG.5D).
  • FIG. 5A shows evaluation of in vitro cytotoxic activity of an anti-TROP2 ADC and unconjugated cytotoxin exatecan against the following cell lines: BxPC-3 (FIG. 5A); MDA-MB-468 (FIG
  • activated ester refers to an ester functional group that is highly susceptible toward attack by a nucleophile.
  • An activated ester can contain a modification to its precursor (or “unactivated”) ester by modification of the acyl or alkoxy moiety of the precursor ester.
  • the precursor ester is modified by incorporation of an electronegative substituent.
  • Non-limiting examples of activated esters include thioesters and derivatives of nitrophenols or penthafluorophenol, esters derivatized with N-hydroxysuccinimide (NHS), e.g., in the presence of dicyclohexylcarbodiimide (DCC), esters derivatized with hydroxybenzotriazole (HOBt), and the like.
  • NHS N-hydroxysuccinimide
  • DCC dicyclohexylcarbodiimide
  • HOBt hydroxybenzotriazole
  • Acyl substituents include, but are not limited to, any of the substituents described herein that result in the formation of a stable moiety (e.g., aliphatic, alkyl, alkenyl, alkynyl, heteroaliphatic, heterocyclic, aryl, heteroaryl, - C(O)C1-C6 alkyl, oxo, imino, thiooxo, cyano, isocyano, amino, azido, nitro, hydroxyl, thiol, halogen, aliphaticamino, heteroaliphaticamino, alkylamino, heteroalkylamino, arylamino, heteroarylamino, alkylaryl, arylalkyl, aliphaticoxy, heteroaliphaticoxy, alkyloxy, heteroalkyloxy, aryloxy, heteroaryloxy, aliphatic thioxy, heteroaliphaticthioxy, alkylthioxy, heteroalkylthioxy, aryl
  • alkoxy,” “alkylamino” and “alkylthio” (or thioalkoxy) are used in their conventional sense and refer to those alkyl groups linked to molecules via an oxygen atom, an amino group, or a sulfur atom, respectively.
  • alkyl by itself or as part of another molecule means, unless otherwise stated, a straight or branched chain, or cyclic hydrocarbon radical, or combination thereof, which may be fully saturated, mono- or polyunsaturated and can include di- and multivalent radicals, having the number of carbon atoms designated (i.e., C 1 -C 10 means one to ten carbons).
  • saturated hydrocarbon radicals include, but are not limited to, groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, sec-butyl, cyclohexyl, (cyclohexyl)methyl, cyclopropylmethyl, homologs and isomers of, for example, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like.
  • An unsaturated alkyl group is one having one or more double bonds or triple bonds.
  • unsaturated alkyl groups include, but are not limited to, vinyl, 2-propenyl, crotyl, 2-isopentenyl, 2-(butadienyl), 2,4- pentadienyl, 3-(1,4-pentadienyl), ethynyl, 1- and 3-propynyl, 3-butynyl, and the higher homologs and isomers.
  • a “lower alkyl” is a shorter chain alkyl group, generally having eight or fewer carbon atoms. Substituents for each of the above noted alkyl groups are selected from the group of acceptable substituents described herein.
  • alkylene by itself or as part of another molecule means a divalent radical derived from an alkane, as exemplified, by (–CH 2 –) n , wherein n may be 1 to about 24.
  • groups include, but are not limited to, groups having 10 or fewer carbon atoms such as the structures –CH 2 CH 2 – and –CH 2 CH 2 CH 2 CH 2 –.
  • alkylene as used herein includes methylene having the structure –CH 2 –, unless otherwise noted.
  • alkylene unless WSGR Ref.
  • alkenylene unless otherwise noted, is also meant to include those groups described herein as “heteroalkenylene.”
  • alkynylene unless otherwise noted, is also meant to include those groups described herein as “heteroalkynylene.” In embodiments are provided novel amino acid sequences.
  • amino acid refers to naturally occurring and non-natural or unnatural amino acids, as well as amino acid analogs and amino acid mimetics that function in a manner similar to the naturally occurring amino acids.
  • Naturally encoded amino acids are the 20 common amino acids (alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine) and pyrolysine and selenocysteine.
  • Amino acid analogs refer to compounds that have the same basic bound to a hydrogen, a carboxyl group, an amino group, and a functional R group. Such analogs may have modified R groups (by way of example, norleucine) or may have modified peptide backbones while still retaining the same basic chemical structure as a naturally occurring amino acid.
  • Non- limiting examples of amino acid analogs include homoserine, norleucine, methionine sulfoxide, methionine methyl sulfonium.
  • Amino acids may be referred to herein by either their name, their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC- IUB Biochemical Nomenclature Commission.
  • nucleotides may be referred to by their commonly accepted single-letter codes.
  • An “amino or carboxy terminus modification group” refers to any molecule that can be attached to a terminal amine group or terminal carboxy group, respectively.
  • such terminal amine groups or terminal carboxy groups may be at the end of polymeric molecules, wherein such polymeric molecules include, but are not limited to, polypeptides, polynucleotides, and polysaccharides.
  • Terminus modification groups include but are not limited to, various water-soluble WSGR Ref. No: 31362-826.601 polymers, peptides or proteins.
  • terminus modification groups include polyethylene glycol or serum albumin.
  • Terminus modification groups may be used to modify therapeutic characteristics of the polymeric molecule, including but not limited to increasing the serum half-life of peptides, polypeptides or proteins.
  • the disclosure provides novel antibodies and antibody variants.
  • the term “antibody” herein refers to a protein consisting of one or more polypeptides substantially encoded by all or part of the antibody genes.
  • the immunoglobulin genes include, but are not limited to, the kappa, lambda, alpha, gamma (IgG1, IgG2, IgG3, and IgG4), delta, epsilon and mu constant region genes, as well as the myriad immunoglobulin variable region genes.
  • Antibody herein is also meant to include full-length antibodies and antibody fragments, and include antibodies that exist naturally in any organism, antibody variants, engineered antibodies and antibody fragments. Antibody herein is also meant to include intact antibody, monoclonal or polyclonal antibodies. Antibody herein also encompasses, multispecific antibodies and/or bispecific antibodies. Antibodies of the present disclosure include human antibodies. Human antibodies are usually made of two light chains and two heavy chains each comprising variable regions and constant regions.
  • the light chain variable region comprises 3 CDRs, identified herein as CDRL1, CDRL2 and CDRL3 flanked by framework regions.
  • the heavy chain variable region comprises 3 CDRs, identified herein as CDRH1, CDRH2 and CDRH3 flanked by framework regions.
  • antibody fragment refers to any form of an antibody other than the full- length form.
  • Antibody fragments herein include antibodies that are smaller components that exist within full-length antibodies, and antibodies that have been engineered, such as antibody variants.
  • Antibody fragments include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, and variable regions, and alternative scaffold non-antibody molecules, bispecific antibodies, and the like (Maynard & Georgiou, Annu. Rev. Biomed.
  • Another functional substructure is a single chain Fv (scFv), comprised of the variable regions of the immunoglobulin heavy and light chain, covalently connected by a peptide linker (Hu et al., Cancer Research, 56, 3055-3061, 1996).
  • scFv single chain Fv
  • These small (Mr 25,000) proteins generally retain specificity and affinity for antigen in a single polypeptide and can provide a convenient building block for larger, antigen-specific molecules.
  • antibody or “antibodies” specifically includes “antibody fragment” and “antibody fragments.” WSGR Ref.
  • ADCs novel antibody drug conjugates
  • ADC antibody-drug conjugate
  • ADC refers to an antibody molecule, or fragment thereof, that is covalently bonded to one or more biologically active molecule(s).
  • the biologically active molecule may be conjugated to the antibody through a linker, polymer, or other covalent bond.
  • ADCs are a potent class of therapeutic constructs that allow targeted delivery of cytotoxic agents to target cells, such as cancer cells. Because of the targeting function, these compounds show a much higher therapeutic index compared to the same systemically delivered agents.
  • ADCs have been developed as intact antibodies or antibody fragments, such as scFvs.
  • the antibody or fragment is linked to one or more copies of drug via a linker that is stable under physiological conditions, but that may be cleaved once inside the target cell.
  • the term "antigen-binding fragment”, as used herein, refers to one or more fragments of an antibody that retain the ability to bind to an antigen. It has been shown that the antigen-binding function of an antibody can be performed by fragments of an intact antibody.
  • binding fragments encompassed within the term "antigen-binding fragment" of an antibody include (i) a Fab fragment, a monovalent fragment consisting of the VL, VH, CL and CH1 domains; (ii) a F(ab')2 fragment, a bivalent fragment comprising two Fab fragments linked by a disulfide bridge at the hinge region; (iii) a Fd fragment consisting of the V H and C H1 domains; (iv) a Fv fragment consisting of the VL and VH domains of a single arm of an antibody, (v) a dAb fragment (Ward et al., Nature 341:544- 546, 1989), which consists of a VH domain; (vi) an isolated complementarity determining region (CDR), e.g., V H CDR3 comprising or not additional sequence (linker, framework region(s) etc.) and (v) a combination of two to six isolated CDRs comprising or not additional sequence (linker
  • the two domains of the Fv fragment, VL and VH are coded for by separate genes, they can be joined, using recombinant methods, by a synthetic linker that enables them to be made as a single polypeptide chain in which the V L and V H regions pair to form monovalent molecules (known as single chain Fv (scFv); see e.g., Bird et al., Science 242:423- 426, 1988); and (Huston et al., Proc. Natl. Acad. Sci. USA 85:5879-5883, 1988).
  • single chain Fv single chain Fv
  • Such single chain antibodies are also intended to be encompassed within the term "antigen-binding fragment" of an antibody.
  • the antigen-binding fragments include binding-domain immunoglobulin fusion proteins comprising (i) a binding domain polypeptide (such as a heavy chain variable region, a light chain variable region, or a heavy chain variable region fused to a light chain variable region via a linker peptide) that is fused to an immunoglobulin hinge region polypeptide, (ii) an immunoglobulin heavy chain CH2 constant region fused to the hinge region, and (iii) an immunoglobulin heavy chain CH3 constant region fused to the CH2 constant region.
  • the hinge region may be modified by replacing one or more cysteine residues with serine residues to prevent WSGR Ref. No: 31362-826.601 dimerization.
  • Such binding-domain immunoglobulin fusion proteins are further disclosed in US 2003/0118592 and US 2003/0133939. These antibody fragments are obtained using conventional techniques known to those with skill in the art, and the fragments are screened for utility in the same manner as are intact antibodies.
  • a typical antigen binding site is comprised of the variable regions formed by the pairing of a light chain immunoglobulin and a heavy chain immunoglobulin. The structure of the antibody variable regions is very consistent and exhibits very similar structures. These variable regions are typically comprised of relatively homologous framework regions (FR) interspaced with three hypervariable regions termed Complementarity Determining Regions (CDRs). The overall binding activity of the antigen binding fragment is often dictated by the sequence of the CDRs.
  • FR homologous framework regions
  • CDRs Complementarity Determining Regions
  • the FRs often play a role in the proper positioning and alignment in three dimensions of the CDRs for optimal antigen binding.
  • CDR sequences are responsible for most antibody-antigen interactions
  • Such framework sequences can be obtained from public DNA databases that include germline antibody gene sequences. These germline sequences will differ from mature antibody gene sequences because they will not include completely assembled variable genes, which are formed by V(D)J joining during B cell maturation. Germline gene sequences will also differ from the sequences of a high affinity secondary repertoire antibody which contains mutations throughout the variable gene but typically clustered in the CDRs. For example, somatic mutations are relatively infrequent in the amino terminal portion of framework region 1 and in the carboxy-terminal portion of framework region 4. Furthermore, many somatic mutations do not significantly alter the binding properties of the antibody. For this reason, it is not necessary to obtain the entire DNA sequence of a particular antibody in order to recreate an intact recombinant antibody having binding properties similar to those of the original antibody.
  • Partial heavy and light chain sequence spanning the CDR regions is typically sufficient for this purpose.
  • the partial sequence is used to determine which germline variable and joining gene segments contributed to the recombined antibody variable genes.
  • the germline sequence is then used to fill in missing portions of the variable regions.
  • Heavy and light chain leader sequences are cleaved during protein maturation and do not contribute to the properties of the final antibody.
  • cloned cDNA sequences can be combined with synthetic oligonucleotides by ligation or PCR amplification.
  • the entire variable region WSGR Ref. No: 31362-826.601 can be synthesized to create an entirely synthetic variable region clone.
  • aromatic refers to a closed ring structure which has at least one ring having a conjugated pi electron system and includes both carbocyclic aryl and heterocyclic aryl (or “heteroaryl” or “heteroaromatic”) groups.
  • the carbocyclic or heterocyclic aromatic group may contain from 5 to 20 ring atoms.
  • the term includes monocyclic rings linked covalently or fused-ring polycyclic (i.e., rings which share adjacent pairs of carbon atoms) groups.
  • An aromatic group can be unsubstituted or substituted.
  • aromatic or aryl groups include phenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, anthracenyl, and phenanthracenyl.
  • heteroaryl are described herein. Substituents for each of the above noted aryl and heteroaryl ring systems are selected from the group of acceptable substituents described herein.
  • aromatic or “aryl” when used in combination with other terms (including but not limited to, aryloxy, arylthioxy, aralkyl) includes both aryl and heteroaryl rings as defined above.
  • aralkyl or “alkaryl” is meant to include those radicals in which an aryl group is attached to an alkyl group (including but not limited to, benzyl, phenethyl, pyridylmethyl and the like) including those alkyl groups in which a carbon atom (including but not limited to, a methylene group) has been replaced by a heteroatom, by way of example only, by an oxygen atom.
  • aryl groups include, but are not limited to, phenoxymethyl, 2- pyridyloxymethyl, 3-(1-naphthyloxy)propyl, and the like.
  • arylene refers to a divalent aryl radical.
  • Non-limiting examples of “arylene” include phenylene, pyridinylene, pyrimidinylene and thiophenylene.
  • Substituents for arylene groups are selected from the group of acceptable substituents described herein.
  • the disclosure concerns polymers such as a bifunctional polymer.
  • a “bifunctional polymer”, also referred to as a “bifunctional linker”, refers to a polymer comprising two functional groups that are capable of reacting specifically with other moieties to form covalent or non-covalent linkages. Such moieties may include, but are not limited to, the side groups on natural or non-natural amino acids or peptides which contain such natural or non-natural amino acids.
  • the other moieties that may be linked to the bifunctional linker or bifunctional polymer may be the same or different moieties.
  • a bifunctional linker may have a functional group reactive with a group on a first peptide, and another functional group which is reactive with a group WSGR Ref.
  • Such moieties may include, but are not limited to, the side groups on natural or non-natural amino acids or peptides which contain such natural or non-natural amino acids (including but not limited to, amino acid side groups) to form covalent or non-covalent linkages.
  • a bi-functional polymer or multi-functional polymer may be any desired length or molecular weight and may be selected to provide a particular desired spacing or conformation between one or more molecules linked to a compound and molecules it binds to, or to the compound.
  • bioavailability refers to the rate and extent to which a substance or its active moiety is delivered from a pharmaceutical dosage form and becomes available at the site of action or in the general circulation.
  • Increases in bioavailability refers to increasing the rate and extent a substance or its active moiety is delivered from a pharmaceutical dosage form and becomes available at the site of action or in the general circulation.
  • an increase in bioavailability may be indicated as an increase in concentration of the substance or its active moiety in the blood when compared to other substances or active moieties.
  • the term “biologically active molecule”, “biologically active moiety” or “biologically active agent” when used herein means any substance which can affect any physical or biochemical properties of a biological system, pathway, molecule, or interaction relating to an organism, including but not limited to, viruses, bacteria, bacteriophage, transposon, prion, insects, fungi, plants, animals, and humans.
  • biologically active molecules include but are not limited to any substance intended for diagnosis, cure, mitigation, treatment, or prevention of disease in humans or other animals, or to otherwise enhance physical or mental well-being of humans or animals.
  • biologically active molecules include, but are not limited to, peptides, proteins, enzymes, small molecule drugs, hard drugs, soft drugs, prodrugs, carbohydrates, inorganic atoms or molecules, dyes, lipids, nucleosides, radionuclides, oligonucleotides, toxins, cells, viruses, liposomes, microparticles and micelles.
  • Classes of biologically active agents that are suitable for use with the methods and compositions described herein include, but are not limited to, drugs, prodrugs, radionuclides, imaging agents, polymers, antibiotics, fungicides, anti-viral agents, anti-inflammatory agents, anti-tumor agents, cardiovascular agents, anti-anxiety agents, hormones, growth factors, steroidal and nonsteroidal agents, microbially derived toxins, and the like.
  • WSGR Ref. No: 31362-826.601 By “modulating biological activity” is meant increasing or decreasing the reactivity of a polypeptide, altering the selectivity of the polypeptide, enhancing or decreasing the substrate selectivity of the polypeptide.
  • Analysis of modified biological activity can be performed by comparing the biological activity of the non-natural polypeptide to that of the natural polypeptide.
  • the disclosure concerns amino acids that have been biosynthetically incorporated in the antibody.
  • biosynthetically refers to any method utilizing a translation system (cellular or non-cellular), including use of at least one of the following components: a polynucleotide, a codon, a tRNA, and a ribosome.
  • non-natural amino acids may be “biosynthetically incorporated” into non-natural amino acid polypeptides using the methods and techniques described herein and as is well known in the art.
  • carbonyl refers to the moiety -C(O)-.
  • Groups containing a carbonyl include but are not limited to a ketone, an aldehyde, an ester, a carboxylic acid, a thioester and an amide. In addition, such groups may be part of linear, branched, or cyclic molecules.
  • chemically cleavable group also referred to as “chemically labile”, as used herein, refers to a group which breaks or cleaves upon exposure to acid, base, oxidizing agents, reducing agents, chemical initiators or radical initiators.
  • chromophore refers to a molecule which absorbs light of visible wavelengths, UV wavelengths or IR wavelengths.
  • a “comparison window,” as used herein, refers a segment of any one of contiguous positions used to compare a sequence to a reference sequence of the same number of contiguous positions after the two sequences are optimally aligned. Such contiguous positions include, but are not limited to a group consisting of from about 20 to about 600 sequential units, including about 50 to about 200 sequential units, and about 100 to about 150 sequential units.
  • sequences include polypeptides and polypeptides containing non-natural amino acids, with the sequential units include, but are not limited to natural and non-natural amino acids.
  • sequences include polynucleotides with nucleotides being the corresponding sequential units.
  • Methods of alignment of sequences for comparison are well-known in the art. Optimal alignment of sequences for comparison can be conducted, including but not limited to, by the local homology algorithm of Smith and Waterman (1970) Adv. Appl. Math.2:482c, by the homology alignment algorithm of Needleman and Wunsch (1970) J. Mol. Biol.48:443, by the search for similarity method of Pearson and Lipman (1988) Proc. Nat’l. Acad. Sci.
  • the BLAST algorithm parameters W, T, and X determine the sensitivity and speed of the alignment.
  • the BLAST algorithm is typically performed with the “low complexity” filter turned off.
  • the BLAST algorithm also performs a statistical analysis of the similarity between two sequences (see, e.g., Karlin and Altschul (1993) Proc. Natl. Acad. Sci. USA 90:5873-5787).
  • One measure of similarity provided by the BLAST algorithm is the smallest sum probability (P(N)), which provides an indication of the probability by which a match between two nucleotide or amino acid sequences would occur by chance.
  • P(N) the smallest sum probability
  • a nucleic acid is considered similar to a reference sequence if the smallest sum probability in a comparison of the test nucleic acid to the reference nucleic acid is less than about 0.2, or less than about 0.01, or less than about 0.001.
  • “conservatively modified variants” applies to both natural and non-natural amino acid and natural and non-natural nucleic acid sequences, and combinations thereof.
  • “conservatively modified variants” refers to those natural and non- natural nucleic acids which encode identical or essentially identical natural and non-natural amino acid sequences, or where the natural and non-natural nucleic acid does not encode a natural and non- natural amino acid sequence, to essentially identical sequences.
  • the codons GCA, GCC, GCG and GCU all encode the amino acid alanine.
  • nucleic acid variations are “silent variations,” which are one species of conservatively modified variations.
  • every natural or non-natural nucleic acid sequence herein which encodes a natural or non-natural polypeptide also describes every possible silent variation of the natural or non-natural WSGR Ref. No: 31362-826.601 nucleic acid.
  • each codon in a natural or non-natural nucleic acid can be modified to yield a functionally identical molecule. Accordingly, each silent variation of a natural and non-natural nucleic acid which encodes a natural and non-natural polypeptide is implicit in each described sequence.
  • amino acid sequences individual substitutions, deletions or additions to a nucleic acid, peptide, polypeptide, or protein sequence which alters, adds or deletes a single natural and non-natural amino acid or a small percentage of natural and non-natural amino acids in the encoded sequence is a “conservatively modified variant” where the alteration results in the deletion of an amino acid, addition of an amino acid, or substitution of a natural and non-natural amino acid with a chemically similar amino acid.
  • Conservative substitution tables providing functionally similar natural amino acids are well known in the art.
  • Conservative substitution tables providing functionally similar amino acids are known to those of ordinary skill in the art.
  • the following eight groups each contain amino acids that are conservative substitutions for one another: 1) Alanine (A), Glycine (G); 2) Aspartic acid (D), Glutamic acid (E); 3) Asparagine (N), Glutamine (Q); 4) Arginine (R), Lysine (K); 5) Isoleucine (I), Leucine (L), Methionine (M), Valine (V); 6) Phenylalanine (F), Tyrosine (Y), Tryptophan (W); 7) Serine (S), Threonine (T); and 8) Cysteine (C), Methionine (M) (see, e.g., Creighton, Proteins: Structures and Molecular Properties (W H Freeman & Co.; 2nd edition, 1993).
  • cycloalkyl and “heterocycloalkyl”, by themselves or in combination with other terms, represent, unless otherwise stated, cyclic versions of “alkyl” and “heteroalkyl”, respectively.
  • a cycloalkyl or heterocycloalkyl includes saturated, partially unsaturated and fully unsaturated ring linkages.
  • a heteroatom can occupy the position at which the heterocycle is attached to the remainder of the molecule.
  • the heteroatom may include, but is not limited to, oxygen, nitrogen or sulfur.
  • the carbocycloalkyl or heterocycloalkyl group can contain from 3 to 20 ring atoms.
  • cycloalkyl include, but are not limited to, cyclopentyl, cyclohexyl, 1-cyclohexenyl, 3-cyclohexenyl, cycloheptyl, cyclooctynyl, and the like.
  • heterocycloalkyl examples include, but are not limited to, 1–(1,2,5,6-tetrahydropyridyl), 1-piperidinyl, 2- piperidinyl, 3-piperidinyl, 4-morpholinyl, 3-morpholinyl, tetrahydrofuran-2-yl, tetrahydrofuran-3-yl, tetrahydrothien-2-yl, tetrahydrothien-3-yl, 1–piperazinyl, 2-piperazinyl, and the like. Additionally, the term encompasses multicyclic structures, including but not limited to, bicyclic and tricyclic ring structures.
  • heterocycloalkylene by itself or as part of another molecule means a divalent radical derived from heterocycloalkyl
  • cycloalkylene by itself or as part of WSGR Ref. No: 31362-826.601 another molecule means a divalent radical derived from cycloalkyl.
  • Substituents for each of the above noted cycloalkyl and heterocycloalkyl ring systems are selected from the group of acceptable substituents described herein.
  • cyclodextrin refers to cyclic carbohydrates consisting of at least six to eight glucose molecules in a ring formation.
  • the outer part of the ring contains water soluble groups; at the center of the ring is a relatively nonpolar cavity able to accommodate small molecules.
  • such groups may be part of linear, branched, or cyclic molecules.
  • detectable label refers to a label which may be observable using analytical techniques including, but not limited to, fluorescence, chemiluminescence, electron-spin resonance, ultraviolet/visible absorbance spectroscopy, mass spectrometry, nuclear magnetic resonance, magnetic resonance, and electrochemical methods.
  • dicarbonyl refers to a group containing at least two moieties selected from the group consisting of -C(O)-, -S(O)-, -S(O) 2 -, and –C(S)-, including, but not limited to, 1,2-dicarbonyl groups, a 1,3-dicarbonyl groups, and 1,4-dicarbonyl groups, and groups containing a least one ketone group, and/or at least one aldehyde groups, and/or at least one ester group, and/or at least one carboxylic acid group, and/or at least one thioester group.
  • Such dicarbonyl groups include diketones, ketoaldehydes, ketoacids, ketoesters, and ketothioesters.
  • such groups may be part of linear, branched, or cyclic molecules.
  • the two moieties in the dicarbonyl group may be the same or different, and may include substituents that would produce, by way of example only, an ester, a ketone, an aldehyde, a thioester, or an amide, at either of the two moieties.
  • drug refers to any substance used in the prevention, diagnosis, alleviation, treatment, or cure of a disease or condition such as cancer, including but not limited to oral, colorectal, gastric, esophageal, hepatocellular, non-small-cell-lung (NSCL), small-cell lung (SCL), ovarian, breast including triple-negative breast, prostate, pancreatic, head and neck, squamous, renal, bladder, cervical, endometrial, thyroid, glioblastoma cancer.
  • DAR drug-to-antibody ratio
  • ADC antibody-drug conjugate
  • the DAR value reflects the homogeneity of the ADC population in the composition, and also indicates the amount of “payload” (e.g., drug or drug-linker) that is loaded onto an antibody and can be delivered to a target (e.g., cell or diseased tissue).
  • DAR can be determined by methods known to a person of ordinary skill in the art, for example, LC-MS (e.g., see Tang, Y. et al., Real- WSGR Ref. No: 31362-826.601 Time Analysis on Drug-Antibody Ratio of Antibody-Drug Conjugates for Synthesis, Process Optimization and Quality Control, Sci Rep 7, 7763 (2017). doi: 10.1038/s41598-017-08151-2; and Chen, Y.
  • LC-MS e.g., see Tang, Y. et al., Real- WSGR Ref. No: 31362-826.601 Time Analysis on Drug-Antibody Ratio of Antibody-Drug Conjugates for
  • an agent, compound or composition being administered includes, but is not limited to, a natural amino acid polypeptide, non-natural amino acid polypeptide, modified natural amino acid polypeptide, modified non-amino acid polypeptide, or an antibody or variant thereof.
  • compositions containing such natural amino acid polypeptides, non-natural amino acid polypeptides, modified natural amino acid polypeptides, modified non-natural amino acid polypeptides, or an antibody or variant thereof can be administered for prophylactic, enhancing, and/or therapeutic treatments.
  • An appropriate “effective” amount in any individual case may be determined using techniques, such as a dose escalation study.
  • the terms “enhance” or “enhancing” means to increase or prolong either in potency or duration a desired effect.
  • “enhancing” the effect of therapeutic agents refers to the ability to increase or prolong, either in potency or duration, the effect of therapeutic agents on during treatment of a disease, disorder or condition.
  • an “enhancing-effective amount,” as used herein, refers to an amount adequate to enhance the effect of a therapeutic agent in the treatment of a disease, disorder or condition. When used in a patient, amounts effective for this use will depend on the severity and course of the disease, disorder or condition, previous therapy, the patient's health status and response to the drugs, and the judgment of the treating physician.
  • the term “eukaryote” refers to organisms belonging to the phylogenetic domain Eucarya, including but not limited to animals (including but not limited to, mammals, insects, reptiles, birds, etc.), ciliates, plants (including but not limited to, monocots, dicots, and algae), fungi, yeasts, flagellates, microsporidia, and protists.
  • WSGR Ref. No: 31362-826.601 The terms “functional group”, “active moiety”, “activating group”, “leaving group”, “reactive site”, “chemically reactive group” and “chemically reactive moiety,” as used herein, refer to portions or units of a molecule at which chemical reactions occur.
  • haloacyl refers to acyl groups which contain halogen moieties, including, but not limited to, -C(O)CH 2 F, -C(O)CF 3 , -C(O)CH 2 OCCl 3 , and the like.
  • haloalkyl refers to alkyl groups which contain halogen moieties, including, but not limited to, -CF3 and –CH2CF3 and the like.
  • halogen as used herein includes fluorine, chlorine, bromine and iodine.
  • halogen may be referred to as “halo.”
  • Non-limiting examples of halogen substituents include -F, -Cl, -Br and -I.
  • Non-limiting examples of halogen ions include fluoride, chloride, bromide and iodide.
  • the term “heavy atom,” as used herein, refers to a group which incorporates an ion or atom which is usually heavier than carbon. Such ions or atoms include, but are not limited to, silicon, tungsten, gold, lead, and uranium.
  • heteroalkyl refers to straight or branched chain, or cyclic hydrocarbon radicals, or combinations thereof, consisting of an alkyl group and at least one heteroatom selected from the group consisting of O, N, Si and S, and wherein the nitrogen and sulfur atoms may optionally be oxidized and the nitrogen heteroatom may optionally be quaternized.
  • the heteroatom(s) O, N and S and Si may be placed at any interior position of the heteroalkyl group or at the position at which the alkyl group is attached to the remainder of the molecule.
  • heterocyclic-based linkage or “heterocycle linkage” refers to a moiety formed from the reaction of a dicarbonyl group with a diamine group. The resulting reaction product is a heterocycle, including a heteroaryl group or a heterocycloalkyl group.
  • heterocycle linkage includes a nitrogen-containing heterocycle linkage, including by way of example only a pyrazole linkage, a pyrrole linkage, an indole linkage, a benzodiazepine linkage, and a pyrazalone linkage.
  • heteroalkylene refers to a divalent radical derived from heteroalkyl, as exemplified, but not limited by, -CH2-CH2-S-CH2-CH2- and –CH2-S-CH2-CH2-NH-CH2-.
  • heteroalkylene groups the same or different heteroatoms can also occupy either or both of the chain termini (including but not limited to, alkyleneoxy, alkylenedioxy, alkyleneamino, alkylenediamino, aminooxyalkylene, and the like). Still further, for alkylene and heteroalkylene linking groups, no orientation of the linking group is implied by the direction in which the formula of the linking group is written. By way of example, the formula –C(O) 2 R’- represents both –C(O) 2 R’- and –R’C(O) 2 -.
  • heteroaryl refers to aryl groups which contain at least one heteroatom selected from the group consisting of N, O and S; wherein the nitrogen and sulfur atoms are optionally oxidized, and the nitrogen atom(s) are optionally quaternized.
  • the heteroaryl group may contain from 5 to 20 ring atoms.
  • the term includes monocyclic rings linked covalently or fused-ring polycyclic (i.e., rings which share adjacent pairs of atoms) groups.
  • Heteroaryl groups may be substituted or unsubstituted.
  • a heteroaryl group may be attached to the remainder of the molecule through a ring heteroatom or a ring carbon atom.
  • heteroaryl groups include benzimidazolyl, benzothiazolyl, furanyl, imidazolyl, indolizinyl, indolyl, isoquinolyl, isothiazolyl, isoxazolyl, naphthyridinyl, oxadiazolyl, oxazolyl, pteridinyl, purinyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, quinolyl, quinoxalinyl, tetrazolyl, thiadiazolyl, thienyl, thiazolyl and triazolyl.
  • heteroaryl groups include 2-benzimidazolyl, 4-benzimidazolyl, 5-benzimidazolyl, 6- benzimidazolyl, 7-benzimidazolyl, 2-benzothiazolyl, 4-benzothiazolyl, 5-benzothiazolyl, 6- benzothiazolyl, 7-benzothiazolyl, 2-furanyl, 3-furanyl, 1-imidazolyl, 2-imidazolyl, 3-imidazolyl, 4- imidazolyl, 5-imidazolyl, 1-indolizinyl, 2-indolizinyl, 3-indolizinyl, 5-indolizinyl, 6-indolizinyl, 7- indolizinyl, 8-indolizinyl, 2-indolyl, 3-indolyl, 4-indolyl, 5-indolyl, 6-indolyl, 7-indolyl, 1- isoquinolyl, 3-isoquinoly
  • WSGR Ref. No: 31362-826.601 The term "humanized or chimeric antibody” refer to a molecule, generally prepared using recombinant techniques, having an antigen binding site derived from an immunoglobulin from a non- human species, (e.g., murine), and the remaining immunoglobulin structure of the molecule based upon the structure and/or sequence of a human immunoglobulin.
  • the humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the hypervariable loops correspond to those of a non-human immunoglobulin and all or substantially all of the framework residues/regions (FR) are those of a human immunoglobulin sequence.
  • the humanized antibody optionally also will comprise at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin.
  • the humanized forms of rodent antibodies will essentially comprise the same CDR sequences of the parental rodent antibodies, although certain amino acid substitutions may be included to increase affinity, increase stability of the humanized antibody, or for other reasons.
  • the antigen-binding site may comprise either complete variable domains fused onto constant domains or only the complementarity determining regions (CDRs) grafted onto appropriate framework regions in the variable domains.
  • Antigen binding sites may be wild type or modified by one or more amino acid substitutions. This eliminates the constant region as an immunogen in human individuals, but the possibility of an immune response to the foreign variable region remains (LoBuglio, A. F.
  • variable regions of both heavy and light chains contain three complementarity-determining regions (CDRs) which vary in response to the antigens in question and determine binding capability, flanked by four framework regions (FRs) which are relatively conserved in a given species and which putatively provide a scaffolding for the CDRs.
  • CDRs complementarity-determining regions
  • variable regions can be "humanized” by grafting CDRs derived from nonhuman antibody on the FRs present in the human antibody to be modified.
  • Application of this approach to various antibodies has been reported by Kettleborough, C. A. et al., "Humanization Of A Mouse Monoclonal Antibody By CDR-Grafting: The Importance Of Framework Residues On Loop Conformation," Protein Engineering 4:773- 3783,1991; Co, M. S. et al., “Humanized Antibodies For Antiviral Therapy,” Proc. Natl. Acad. Sci. (USA) 88:2869-2873,1991; Carter, P.
  • humanized antibodies preserve all CDR sequences (for example, a humanized mouse antibody which contains all six CDRs from the mouse antibodies).
  • humanized antibodies have one or more CDRs (one, two, three, four, five, six) which are altered with respect to the original antibody, which are also termed one or more CDRs "derived from” one or more CDRs from the original antibody.
  • CDRs one, two, three, four, five, six
  • the term “identical,” as used herein, refers to two or more sequences or subsequences which are the same.
  • substantially identical refers to two or more sequences which have a percentage of sequential units which are the same when compared and aligned for maximum correspondence over a comparison window, or designated region as measured using comparison algorithms or by manual alignment and visual inspection.
  • two or more sequences may be “substantially identical” if the sequential units are about 60% identical, about 65% identical, about 70% identical, about 75% identical, about 80% identical, about 85% identical, about 90% identical, or about 95% identical over a specified region. Such percentages describe the “percent identity” of two or more sequences.
  • the identity of a sequence can exist over a region that is at least about 75-100 sequential units in length, over a region that is about 50 sequential units in length, or, where not specified, across the entire sequence. This definition also refers to the complement of a test sequence.
  • two or more polypeptide sequences are identical when the amino acid residues are the same, while two or more polypeptide sequences are “substantially identical” if the amino acid residues are about 60% identical, about 65% identical, about 70% identical, about 75% identical, about 80% identical, about 85% identical, about 90% identical, or about 95% identical over a specified region.
  • the identity can exist over a region that is at least about 75 to about 100 amino acids in length, over a region that is about 50 amino acids in length, or, where not specified, across the entire sequence of a polypeptide sequence.
  • two or more polynucleotide sequences are identical when the nucleic acid residues are the same, while two or more polynucleotide sequences are “substantially identical” if the nucleic acid residues are about 60% identical, about 65% identical, about 70% identical, about 75% identical, about 80% identical, about 85% identical, about 90% identical, or about 95% identical over a specified region.
  • the identity can exist over a region that is at least about 75 to about 100 nucleic acids in length, over a region that is about 50 nucleic acids in length, or, where not specified, across the entire sequence of a polynucleotide sequence.
  • immunogenicity refers to an antibody response to administration of a therapeutic drug.
  • the immunogenicity toward therapeutic non-natural amino acid polypeptides WSGR Ref. No: 31362-826.601 can be obtained using quantitative and qualitative assays for detection of anti-non-natural amino acid polypeptides antibodies in biological fluids.
  • assays include, but are not limited to, Radioimmunoassay (RIA), Enzyme-linked immunosorbent assay (ELISA), luminescent immunoassay (LIA), and fluorescent immunoassay (FIA).
  • Isolated refers to separating and removing a component of interest from components not of interest. Isolated substances can be in either a dry or semi-dry state, or in solution, including but not limited to an aqueous solution. The isolated component can be in a homogeneous state or the isolated component can be a part of a pharmaceutical composition that comprises additional pharmaceutically acceptable carriers and/or excipients.
  • Purity and homogeneity may be determined using analytical chemistry techniques including, but not limited to, polyacrylamide gel electrophoresis or high-performance liquid chromatography.
  • a component of interest is isolated and is the predominant species present in a preparation, the component is described herein as substantially purified.
  • the term “purified,” as used herein, may refer to a component of interest which is at least 85% pure, at least 90% pure, at least 95% pure, at least 99% or greater pure.
  • nucleic acids or proteins are “isolated” when such nucleic acids or proteins are free of at least some of the cellular components with which it is associated in the natural state, or that the nucleic acid or protein has been concentrated to a level greater than the concentration of its in vivo or in vitro production.
  • a gene is isolated when separated from open reading frames which flank the gene and encode a protein other than the gene of interest.
  • label refers to a substance which is incorporated into a compound and is readily detected, whereby its physical distribution may be detected and/or monitored.
  • linkage refers to a bond or chemical moiety formed from a chemical reaction between the functional group of one group, such as a linker of the present disclosure, and another molecule.
  • bonds may include, but are not limited to, covalent linkages and non-covalent bonds, while such chemical moieties may include, but are not limited to, esters, carbonates, imines, phosphate esters, hydrazones, acetals, orthoesters, peptide linkages, oximes and oligonucleotide linkages.
  • Hydrolytically stable linkages mean that the linkages are substantially stable in water and do not react with water at useful pH values, including but not limited to, under physiological conditions for an extended period of time, perhaps even indefinitely.
  • Hydrolytically unstable or degradable linkages mean that the linkages are degradable in water or in WSGR Ref. No: 31362-826.601 aqueous solutions, including for example, blood.
  • Enzymatically unstable or degradable linkages mean that the linkage can be degraded by one or more enzymes.
  • PEG and related polymers may include degradable linkages in the polymer backbone or in the linker group between the polymer backbone and one or more of the terminal functional groups of the polymer molecule.
  • Such degradable linkages include but are not limited to ester linkages formed by the reaction of PEG carboxylic acids or activated PEG carboxylic acids with alcohol groups on a biologically active agent, wherein such ester groups generally hydrolyze under physiological conditions to release the biologically active agent.
  • hydrolytically degradable linkages include but are not limited to carbonate linkages; imine linkages resulted from reaction of an amine and an aldehyde; phosphate ester linkages formed by reacting an alcohol with a phosphate group; hydrazone linkages which are reaction product of a hydrazide and an aldehyde; acetal linkages that are the reaction product of an aldehyde and an alcohol; orthoester linkages that are the reaction product of a formate and an alcohol; peptide linkages formed by an amine group, including but not limited to, at an end of a polymer such as PEG, and a carboxyl group of a peptide; and oligonucleotide linkages formed by a phosphoramidite group, including but not limited to, at the end of a polymer, and a 5' hydroxyl group of an oligonucleotide.
  • linker refers to any multivalent group that connects, or is capable of connecting, a first group to at least one other group.
  • a linker is a bivalent or a trivalent organic moiety that connects a drug (first group) to a biologically active agent (second group), e.g., via a linkage or adduct moiety, or that connects a drug (first group) to a reactive moiety (second group), wherein the reactive moiety is capable of reacting with a biologically active agent.
  • Linkers can be susceptible to cleavage (cleavable linkers), such as, acid-induced cleavage, photo-induced cleavage, peptidase-induced cleavage, esterase-induced cleavage, and disulfide bond cleavage, and so on, at conditions under which the drug and the at least one other group remains active.
  • linkers can be substantially resistant to cleavage (e.g., stable linker or non-cleavable linker).
  • the linker is a bivalent or trivalent group comprising, or consisting of, at least one moiety, wherein each at least one moiety is independently selected from the group consisting of a bond, unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -C(S)-, -N(R w )-, -S(O) 0-2 -, methine (-CH)-, an amino acid, a peptide, a disulfide (-S-S-) and a phosphate-containing moiety; and combinations thereof; wherein: each nn is independently an integer from 1 to 100; each Rw is independently H, C1-C8 alkyl or a bond; and each phosphate-containing moiety is independently selected from the group consisting of a phosphate ester, a pyrophosphate ester, a tri
  • the formula –C(O)CH2CH2– represents both *– C(O)CH2CH2– and –C(O)CH2CH2–*, wherein * denotes a point of connection, for example, connection to a drug.
  • * denotes a point of connection, for example, connection to a drug.
  • a linker is not a bond.
  • a linker is a bivalent moiety that connects a first group and a second group.
  • the linker is a trivalent moiety that connects a first group, a second group and a third group.
  • a trivalent moiety is C(H) (i.e., methine) or N.
  • a linker is a tetravalent moiety that connects a first group, a second group and a third group.
  • a linker connects at least a first group and a second group, wherein the first group is a drug, and the second group is a biologically active polypeptide or protein.
  • the biologically active polypeptide or protein contains at least one non-natural amino acid.
  • the linker connects the drug to a non-natural amino acid of the biologically active polypeptide or protein.
  • the biologically active polypeptide or protein is an antibody.
  • the antibody connected to a drug via a linker can be an antibody- drug conjugate (ADC), such as an ADC of the present disclosure.
  • ADC antibody- drug conjugate
  • a linker connects at least a first group and a second group, wherein the first group is a drug, and the second group is a reactive moiety.
  • the second group is a reactive moiety that is capable of reacting with a biologically active polypeptide or protein.
  • the biologically active polypeptide or protein contains at least one non-natural amino acid.
  • the reactive moiety is capable of reacting with a non-natural amino acid of the biologically active polypeptide or protein.
  • the biologically active polypeptide or protein is an antibody.
  • a first linker is connected to a second linker, and the combined linkers (a composite linker) connects at least a first group and a second group.
  • a composite linker of the present disclosure can contain 2, 3, 4, 5, 6, 7, 8, 9, 10 or more linker groups.
  • a first, second and third linker group are joined together to provide a composite linker that can connect a first group (e.g., a drug) to at least one other group, such as a reactive moiety and/or a WSGR Ref. No: 31362-826.601 biologically active polypeptide or protein (e.g., an antibody.
  • the biologically active polypeptide or protein contains a non-natural amino acid.
  • a linker is linear. In other embodiments, a linker is branched. In some embodiments, a linker is a phosphate-based linker.
  • phosphate-based linker refers to a linker comprising a phosphate- based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate and/or a diphosphorthioate.
  • medium refers to any culture medium used to grow and harvest cells and/or products expressed and/or secreted by such cells.
  • Such “medium” or “media” include, but are not limited to, solution, solid, semi-solid, or rigid supports that may support or contain any host cell, including, by way of example, bacterial host cells, yeast host cells, insect host cells, plant host cells, eukaryotic host cells, mammalian host cells, CHO cells, prokaryotic host cells, E. coli, or Pseudomonas host cells, and cell contents.
  • Such “medium” or “media” includes, but is not limited to, medium or media in which the host cell has been grown into which a polypeptide has been secreted, including medium either before or after a proliferation step.
  • Such “medium” or “media” also includes, but is not limited to, buffers or reagents that contain host cell lysates, by way of example a polypeptide produced intracellularly, and the host cells are lysed or disrupted to release the polypeptide.
  • metabolite refers to a derivative of a compound, by way of example natural amino acid polypeptide, a non-natural amino acid polypeptide, a modified natural amino acid polypeptide, or a modified non-natural amino acid polypeptide, that is formed when the compound, by way of example natural amino acid polypeptide, non-natural amino acid polypeptide, modified natural amino acid polypeptide, or modified non-natural amino acid polypeptide, is metabolized.
  • pharmaceutically active metabolite refers to a biologically active derivative of a compound, by way of example natural amino acid polypeptide, a non-natural amino acid polypeptide, a modified natural amino acid polypeptide, or a modified non-natural amino acid polypeptide, that is formed when such a compound, by way of example a natural amino acid polypeptide, non-natural amino acid polypeptide, modified natural amino acid polypeptide, or modified non-natural amino acid polypeptide, is metabolized.
  • metabolite or “active metabolite” also refers to biologically active derivatives of a compound, by way of example metabolizing phosphate linkages including monophosphate, diphosphate, pyrophosphate and triphosphate but not limited to such.
  • WSGR Ref. No: 31362-826.601 The term “metabolized,” as used herein, refers to the sum of the processes by which a particular substance is changed by an organism. Such processes include, but are not limited to, hydrolysis reactions and reactions catalyzed by enzymes. Further information on metabolism may be obtained from The Pharmacological Basis of Therapeutics, 9th Edition, McGraw-Hill (1996).
  • metabolites of natural amino acid polypeptides, non-natural amino acid polypeptides, modified natural amino acid polypeptides, or modified non-natural amino acid polypeptides may be identified either by administration of the natural amino acid polypeptides, non- natural amino acid polypeptides, modified natural amino acid polypeptides, or modified non-natural amino acid polypeptides to a host and analysis of tissue samples from the host, or by incubation of natural amino acid polypeptides, non-natural amino acid polypeptides, modified natural amino acid polypeptides, or modified non-natural amino acid polypeptides with hepatic cells in vitro and analysis of the resulting compounds.
  • modified refers to the presence of a change to a natural amino acid, a non-natural amino acid, a natural amino acid polypeptide or a non-natural amino acid polypeptide. Such changes, or modifications, may be obtained by post synthesis modifications of natural amino acids, non-natural amino acids, natural amino acid polypeptides or non-natural amino acid polypeptides, or by co-translational, or by post-translational modification of natural amino acids, non-natural amino acids, natural amino acid polypeptides or non-natural amino acid polypeptides.
  • modulated serum half-life refers to positive or negative changes in the circulating half-life of a modified biologically active molecule relative to its non-modified form.
  • the modified biologically active molecules include, but are not limited to, natural amino acid, non-natural amino acid, natural amino acid polypeptide or non-natural amino acid polypeptide.
  • serum half-life is measured by taking blood samples at various time points after administration of the biologically active molecule or modified biologically active molecule and determining the concentration of that molecule in each sample. Correlation of the serum concentration with time allows calculation of the serum half-life.
  • modulated serum half-life may be an increased in serum half-life, which may enable an improved dosing regimen or avoid toxic effects. Such increases in serum may be at least about two-fold, at least about three-fold, at least about five-fold, or at least about ten-fold.
  • modulated therapeutic half-life refers to positive or negative change in the half-life of the therapeutically effective amount of a modified biologically active molecule, relative to its non-modified form.
  • the modified biologically active WSGR Ref. No: 31362-826.601 molecules include, but are not limited to, natural amino acid, non-natural amino acid, natural amino acid polypeptide or non-natural amino acid polypeptide.
  • therapeutic half-life is measured by measuring pharmacokinetic and/or pharmacodynamic properties of the molecule at various time points after administration.
  • Increased therapeutic half-life may enable a particular beneficial dosing regimen, a particular beneficial total dose, or avoids an undesired effect.
  • the increased therapeutic half-life may result from increased potency, increased or decreased binding of the modified molecule to its target, an increase or decrease in another parameter or mechanism of action of the non-modified molecule, or an increased or decreased breakdown of the molecules by enzymes such as, by way of example only, proteases.
  • Methods for evaluating therapeutic half-life are known in the art and may be used for evaluating the therapeutic half-life of antibodies and antibody drug conjugates of the present disclosure.
  • nanoparticle refers to a particle which has a particle size of within a range of about 0.1 nm to about 1000 nm.
  • the nanoparticle has a particle size of within a range of about 0.1 nm to about 750 nm. In some embodiments, the nanoparticle has a particle size of within a range of about 1 nm to about 500 nm.
  • non-eukaryote refers to non-eukaryotic organisms.
  • a non-eukaryotic organism may belong to the Eubacteria, (which includes but is not limited to, Escherichia coli, Thermus thermophilus, or Bacillus stearothermophilus, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas putida), phylogenetic domain, or the Archaea, which includes, but is not limited to, Methanococcus jannaschii, Methanobacterium thermoautotrophicum, Archaeoglobus fulgidus, Pyrococcus furiosus, Pyrococcus horikoshii, Aeuropyrum pernix, or Halobacterium such as Haloferax volcanii and Halobacterium species NRC- 1, or phylogenetic domain.
  • Eubacteria which includes but is not limited to, Escherichia coli, Thermus thermophilus, or Bacillus stearothermophilus, P
  • non-natural amino acid refers to an amino acid that is not one of the 20 common amino acids or pyrolysine or selenocysteine.
  • Other terms that may be used synonymously with the term “non-natural amino acid” herein include “non-naturally encoded amino acid,” “unnatural amino acid,” “non-naturally-occurring amino acid,” and variously hyphenated and non-hyphenated versions thereof.
  • non-natural amino acid includes, but is not limited to, amino acids which occur naturally by modification of a naturally encoded amino acid (including but not limited to, the 20 common amino acids or pyrrolysine and selenocysteine) but are not themselves incorporated into a growing polypeptide chain by the translation complex.
  • naturally- occurring amino acids include, but are not limited to, N- acetylglucosaminyl-L-serine, N-acetylglucosaminyl-L-threonine, and O-phosphotyrosine.
  • non-natural amino acid includes, but is not limited to, amino acids which do WSGR Ref.
  • nucleic acid refers to deoxyribonucleotides, deoxyribonucleosides, ribonucleosides or ribonucleotides and polymers thereof in either single- or double-stranded form.
  • nucleic acids and nucleic acid polymers include, but are not limited to, (i) analogues of natural nucleotides which have similar binding properties as a reference nucleic acid and are metabolized in a manner similar to naturally occurring nucleotides; (ii) oligonucleotide analogs including, but are not limited to, PNA (peptidonucleic acid), analogs of DNA used in antisense technology (phosphorothioates, phosphoroamidates, and the like); (iii) conservatively modified variants thereof (including but not limited to, degenerate codon substitutions) and complementary sequences and sequence explicitly indicated.
  • PNA peptidonucleic acid
  • analogs of DNA used in antisense technology phosphorothioates, phosphoroamidates, and the like
  • conservatively modified variants thereof including but not limited to, degenerate codon substitutions
  • degenerate codon substitutions may be achieved by generating sequences in which the third position of one or more selected (or all) codons is substituted with mixed-base and/or deoxyinosine residues (Batzer et al., Nucleic Acid Res.19:5081, 1991; Ohtsuka et al., J. Biol. Chem.260:2605-2608, 1985; and Rossolini et al., Mol. Cell. Probes 8:91-98, 1994).
  • the term “optionally substituted” as used herein means substituted or unsubstituted.
  • a substance, group or moiety when a substance, group or moiety is defined as optionally substituted, the substance, group or moiety can be a substituted group or an unsubstituted group.
  • optionally substituted alkyl includes substituted alkyl and unsubstituted alkyl. Accordingly, the terms “substituted and unsubstituted” and “optionally substituted” may be used interchangeably.
  • oxidizing agent refers to a compound or material which is capable of removing an electron from a compound being oxidized.
  • oxidizing agents include, but are not limited to, oxidized glutathione, cystine, cystamine, oxidized dithiothreitol, oxidized erythreitol, and oxygen.
  • oxidizing agents are suitable for use in the methods and compositions described herein.
  • pharmaceutically acceptable refers to a material, including but not limited, to a salt, binder, adjuvant, excipient, carrier or diluent, which does not abrogate the biological activity or properties of the compound, and is relatively nontoxic, i.e., the material may be administered to an individual without causing undesirable biological effects or interacting in a deleterious manner with any of the components of the composition in which it is contained.
  • photocleavable group refers to a group which breaks upon exposure to light. WSGR Ref.
  • photocrosslinker refers to a compound comprising two or more functional groups which, upon exposure to light, are reactive and form a covalent or non-covalent linkage with two or more monomeric or polymeric molecules.
  • polymer refers to a molecule composed of repeated subunits. Such molecules include, but are not limited to, polypeptides, polynucleotides, or polysaccharides or polyalkylene glycols. Polymers of the disclosure can be linear or branched polymeric polyether polyols including, but are not limited to, polyethylene glycol, polypropylene glycol, polybutylene glycol, and derivatives thereof.
  • polymers have average molecular weights between about 0.1 kDa to about 100 kDa.
  • polymers include, but are not limited to, between about 100 Da and about 100,000 Da or more.
  • the molecular weight of the polymer may be between about 100 Da and about 100,000 Da, including but not limited to, about 100,000 Da, about 95,000 Da, about 90,000 Da, about 85,000 Da, about 80,000 Da, about 75,000 Da, about 70,000 Da, about 65,000 Da, about 60,000 Da, about 55,000 Da, about 50,000 Da, about 45,000 Da, about 40,000 Da, about 35,000 Da, about 30,000 Da, about 25,000 Da, about 20,000 Da, about 15,000 Da, about 10,000 Da, about 9,000 Da, about 8,000 Da, about 7,000 Da, about 6,000 Da, about 5,000 Da, about 4,000 Da, about 3,000 Da, about 2,000 Da, about 1,000 Da, about 900 Da, about 800 Da, about 700 Da, about 600 Da, about 500 Da, 400 Da, about 300 Da, about 200 Da, and about 100 Da.
  • molecular weight of the polymer is between about 100 Da and about 50,000 Da. In some embodiments, the molecular weight of the polymer is between about 100 Da and about 40,000 Da. In some embodiments, the molecular weight of the polymer is between about 1,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the polymer is between about 2,000 to about 50,000 Da. In some embodiments, the molecular weight of the polymer is between about 5,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the polymer is between about 10,000 Da and about 40,000 Da. In some embodiments, the poly(ethylene glycol) molecule is a branched polymer.
  • the molecular weight of the branched chain PEG may be between about 1,000 Da and about 100,000 Da, including but not limited to, about 100,000 Da, about 95,000 Da, about 90,000 Da, about 85,000 Da, about 80,000 Da, about 75,000 Da, about 70,000 Da, about 65,000 Da, about 60,000 Da, about 55,000 Da, about 50,000 Da, about 45,000 Da, about 40,000 Da, about 35,000 Da, about 30,000 Da, about 25,000 Da, about 20,000 Da, about 15,000 Da, about 10,000 Da, about 9,000 Da, about 8,000 Da, about 7,000 Da, about 6,000 Da, about 5,000 Da, about 4,000 Da, about 3,000 Da, about 2,000 Da, and about 1,000 Da.
  • the molecular weight of the branched chain PEG is between about 1,000 Da and about 50,000 Da. In some WSGR Ref. No: 31362-826.601 embodiments, the molecular weight of the branched chain PEG is between about 1,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the branched chain PEG is between about 5,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the branched chain PEG is between about 5,000 Da and about 20,000 Da. In other embodiments, the molecular weight of the branched chain PEG is between about 2,000 to about 50,000 Da.
  • PEGylating or “PEGylated” is meant to refer to the covalent bonding of the specified synthetic amino acid to a polyethylene glycol (PEG) molecule.
  • the method can comprise contacting an isolated polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety that reacts with polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety
  • ADC polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety that reacts with the synthetic amino acid is meant to refer to the covalent bonding of the specified synthetic amino acid to a polyethylene glycol (PEG) molecule.
  • the method can comprise contacting an isolated polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety that reacts with polypeptide comprising a synthetic amino acid with a water-soluble polymer
  • polypeptide “peptide” and “protein” are used interchangeably herein to refer to a polymer of amino acid residues. That is, a description directed to a polypeptide applies equally to a description of a peptide and a description of a protein, and vice versa. The terms apply to naturally occurring amino acid polymers as well as amino acid polymers in which one or more amino acid residues is a non-natural amino acid. Additionally, such “polypeptides,” “peptides” and “proteins” include amino acid chains of any length, including full length proteins, wherein the amino acid residues are linked by covalent peptide bonds.
  • a “peptide” can refer to a polymer of 2 to 12 amino acids, wherein the amino acid residues are linked by covalent peptide bonds. In some embodiments, a peptide contains 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 amino acids. In some embodiments, a peptide contains 2, 3, 4, 5 or 6 amino acids. In some embodiments, a peptide contains 2, 3 or 4 amino acids; non-limiting examples include a dipeptide, a tripeptide and a tetrapeptide.
  • post-translationally modified refers to any modification of a natural or non-natural amino acid which occurs after such an amino acid has been translationally incorporated into a polypeptide chain.
  • prodrug or “pharmaceutically acceptable prodrug” as used herein refers to an agent that is converted into the parent drug in vivo or in vitro, which does not abrogate the biological WSGR Ref. No: 31362-826.601 activity or properties of the drug, and is relatively nontoxic, i.e., the material may be administered to an individual without causing undesirable biological effects or interacting in a deleterious manner with any of the components of the composition in which it is contained.
  • Prodrugs are generally drug precursors that, following administration to a subject and subsequent absorption, are converted to an active, or a more active species via some process, such as conversion by a metabolic pathway. Some prodrugs have a chemical group present on the prodrug that renders it less active and/or confers solubility or some other property to the drug. Once the chemical group has been cleaved and/or modified from the prodrug the active drug is generated. Prodrugs are converted into active drug within the body through enzymatic or non-enzymatic reactions. Prodrugs may provide improved physiochemical properties such as better solubility, enhanced delivery characteristics, such as specifically targeting a particular cell, tissue, organ or ligand, and improved therapeutic value of the drug.
  • prodrugs include, but are not limited to, (i) ease of administration compared with the parent drug; (ii) the prodrug may be bioavailable by oral administration whereas the parent is not; and (iii) the prodrug may also have improved solubility in pharmaceutical compositions compared with the parent drug.
  • a prodrug includes a pharmacologically inactive, or reduced activity, derivative of an active drug.
  • Prodrugs may be designed to modulate the amount of a drug or biologically active molecule that reaches a desired site of action through the manipulation of the properties of a drug, such as physiochemical, biopharmaceutical, or pharmacokinetic properties.
  • prodrug a non-natural amino acid polypeptide which is administered as an ester (the “prodrug”) to facilitate transmittal across a cell membrane where water solubility is detrimental to mobility and that is then metabolically hydrolyzed to the carboxylic acid, the active entity, once inside the cell where water solubility is beneficial.
  • Prodrugs may be designed as reversible drug derivatives, for use as modifiers to enhance drug transport to site-specific tissues.
  • prophylactically effective amount refers to an amount of a composition containing at least one non-natural amino acid polypeptide or at least one modified non- natural amino acid polypeptide prophylactically applied to a patient which will relieve to some extent one or more of the symptoms of a disease, condition or disorder being treated. In such prophylactic applications, such amounts may depend on the patient's state of health, weight, and the like. It is considered well within the skill of the art for one to determine such prophylactically effective amounts by routine experimentation, including, but not limited to, a dose escalation clinical trial.
  • protected refers to the presence of a “protecting group” or moiety that prevents reaction of the chemically reactive functional group under certain reaction conditions.
  • the protecting group will vary depending on the type of chemically reactive group being protected. WSGR Ref.
  • the protecting group may be selected from tert-butyloxycarbonyl (t-Boc) and 9-fluorenylmethoxycarbonyl (Fmoc);
  • the chemically reactive group is a thiol, the protecting group may be orthopyridyldisulfide; and
  • the chemically reactive group is a carboxylic acid, such as butanoic or propionic acid, or a hydroxyl group, the protecting group may be benzyl or an alkyl group such as methyl, ethyl, or tert- butyl.
  • blocking/protecting groups may be selected from: Additionally, protecting groups include, but are not limited to, including photolabile groups such as Nvoc and MeNvoc and other protecting groups known in the art. Other protecting groups are described in Greene and Wuts, Protective Groups in Organic Synthesis, 3rd Ed., John Wiley & Sons, New York, NY, 1999, which is incorporated herein by reference in its entirety.
  • the term “reactive compound,” as used herein, refers to a compound which under appropriate conditions is reactive toward another atom, molecule or compound.
  • recombinant host cell refers to a cell which includes an exogenous polynucleotide, wherein the methods used to insert the exogenous polynucleotide into a cell include, but are not limited to, direct uptake, transduction, f-mating, or other methods known in the art to create recombinant host cells.
  • exogenous polynucleotide may be a nonintegrated vector, including but not limited to a plasmid, or may be integrated into the host genome.
  • redox-active agent refers to a molecule which oxidizes or reduces another molecule, whereby the redox active agent becomes reduced or oxidized.
  • redox active agent include, but are not limited to, ferrocene, quinones, Ru 2+/3+ complexes, Co 2+/3+ complexes, and Os 2+/3+ complexes.
  • a redox-active agent is a redox-active amino acid.
  • reducing agent refers to a compound or material which is capable of adding an electron to a compound being reduced. By way of example reducing agents include, but WSGR Ref.
  • No: 31362-826.601 are not limited to, dithiothreitol (DTT), 2-mercaptoethanol, dithioerythritol, cysteine, cysteamine (2- aminoethanethiol), and reduced glutathione.
  • DTT dithiothreitol
  • 2-mercaptoethanol 2-mercaptoethanol
  • dithioerythritol cysteine
  • cysteamine (2- aminoethanethiol
  • reduced glutathione may be used, by way of example only, to maintain sulfhydryl groups in the reduced state and to reduce intra- or intermolecular disulfide bonds.
  • the term “resin” as used herein refers to high molecular weight, insoluble polymer beads. By way of example only, such beads may be used as supports for solid phase peptide synthesis, or sites for attachment of molecules prior to purification.
  • saccharide refers to a series of carbohydrates including but not limited to sugars, monosaccharides, oligosaccharides, and polysaccharides.
  • safety or “safety profile” as used herein, refers to side effects that might be related to administration of a drug relative to the number of times the drug has been administered. By way of example, a drug which has been administered many times and produced only mild or no side effects is said to have an excellent safety profile.
  • subject refers to an animal which is the object of treatment, observation or experiment. By way of example only, a subject may be, but is not limited to, a mammal including, but not limited to, a human.
  • substantially purified refers to a component of interest that may be substantially or essentially free of other components which normally accompany or interact with the component of interest prior to purification.
  • a component of interest may be “substantially purified” when the preparation of the component of interest contains less than about 30%, less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 5%, less than about 4%, less than about 3%, less than about 2%, or less than about l% (by dry weight) of contaminating components.
  • a “substantially purified” component of interest may have a purity level of about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 96%, about 97%, about 98%, about 99% or greater.
  • a natural amino acid polypeptide or a non-natural amino acid polypeptide may be purified from a native cell, or host cell in the case of recombinantly produced natural amino acid polypeptides or non-natural amino acid polypeptides.
  • a preparation of a natural amino acid polypeptide or a non-natural amino acid polypeptide may be “substantially purified” when the preparation contains less than about 30%, less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 5%, less than about 4%, less than about 3%, less than about 2%, or less than about l% (by dry weight) of contaminating material.
  • the natural amino acid polypeptide or non-natural amino acid polypeptide may be present at about 30%, about 25%, about WSGR Ref.
  • the natural amino acid polypeptide or non-natural amino acid polypeptide may be present in the culture medium at about 5g/L, about 4g/L, about 3g/L, about 2g/L, about 1g/L, about 750mg/L, about 500mg/L, about 250mg/L, about 100mg/L, about 50mg/L, about 10mg/L, or about 1mg/L or less of the dry weight of the cells.
  • substantially purified natural amino acid polypeptides or non-natural amino acid polypeptides may have a purity level of about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99% or greater as determined by appropriate methods, including, but not limited to, SDS/PAGE analysis, RP-HPLC, SEC, and capillary electrophoresis.
  • substituteduent(s) refers to group(s) which can be used to replace another group on a molecule.
  • substituent groups include, but are not limited to, halogen, C 1 -C 10 alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl, C 1 -C 10 alkoxy, substituted C 1 -C 10 alkoxy, C 5 -C 12 aralkyl, C 3 -C 12 cycloalkyl, C4-C12 cycloalkenyl, C2-C12 alkoxyalkyl, C5-C12 alkoxyaryl, C5-C12 aryloxyalkyl, C7-C12 oxyaryl, C 1 -C 6 alkylsulfinyl, C 1 -C 10 alkylsulfonyl, wherein m is from 1 to 8, aryl, substituted aryl (including but not limited to phenyl or substituted phenyl), haloalkyl (including but not limited to fluoroalkyl), heterocyclic radical, substituted heterocyclic radical, nitro
  • R group in the preceding list includes, but is not limited to, H, alkyl, substituted alkyl, aryl, substituted aryl, halogen or alkaryl.
  • substituent groups are specified by their conventional chemical formulas, written from left to right, they equally encompass the chemically identical substituents that would result from writing the structure from right to left; for example, - CH2O- is equivalent to –OCH2-.
  • R groups When two R groups are attached to the same nitrogen atom, they can be combined with the nitrogen atom to form a 5-, 6-, or 7-membered ring.
  • -NR 2 is meant to include, but not be limited to, 1-pyrrolidinyl and 4-morpholinyl.
  • terapéuticaally effective amount refers to the amount of a composition containing at least one non-natural amino acid polypeptide and/or at least one modified non-natural amino acid polypeptide administered to a patient already suffering from a disease, condition or disorder, sufficient to cure or at least partially arrest, or relieve to some extent one or more of the symptoms of the disease, disorder or condition being treated.
  • the effectiveness of such compositions depends on conditions including, but not limited to, the severity and course of the disease, disorder or condition, previous therapy, the patient's health status and response to the drugs, and the judgment of the treating physician.
  • therapeutically effective amounts may be determined by routine experimentation, including but not limited to a dose escalation clinical trial.
  • cytotoxic refers to a cytotoxic compound which can cause harm, disturbances, or death.
  • Toxic moieties include, but are not limited to, a drug comprising or consisting of exatecan, or an analog or derivative thereof.
  • treat include alleviating, preventing, abating or ameliorating a disease or condition symptoms, preventing additional symptoms, ameliorating or preventing the underlying metabolic causes of symptoms, inhibiting the disease or condition, e.g., arresting the development of the disease or condition, relieving the disease WSGR Ref. No: 31362-826.601 or condition, causing regression of the disease or condition, relieving a condition caused by the disease or condition, or stopping the symptoms of the disease or condition.
  • the terms “treat,” “treated,” “treating” or “treatment”, include, but are not limited to, prophylactic and/or therapeutic treatments.
  • treat can refer to the decrease, reduction or amelioration of one or more symptoms or conditions or diseases associated with an antigen related or associated cancer.
  • treat can refer to the administration of an ADC of the present disclosure to a subject in need thereof to decrease, reduce, improve, alter, relieve, affect or ameliorate an antigen related or associated cancer or disease or symptom or condition, or the predisposition toward a condition.
  • capable of specific binding refers to protein or peptide (e.g., antibody) binding to a predetermined target substance (e.g., an antigen and/or groups of antigens), e.g.
  • binding to a target cell or “binding to a cancer cell” is to be understand as referring to protein or peptide (e.g., antibody) binding to a predetermined target substance (e.g. antigen or antigens) that is expressed on such a cell.
  • a predetermined target substance e.g. antigen or antigens
  • the protein or peptide binds with an affinity of at least about l x 10 7 M1, and/or binds to the predetermined target substance (e.g., antigen, antigens or cell) with an affinity that is at least two-fold greater than its affinity for binding to a non-specific control substance (e.g., BSA, casein, non-cancer cells) other than the predetermined target substance or a closely-related target substance.
  • a non-specific control substance e.g., BSA, casein, non-cancer cells
  • water-soluble polymer refers to any polymer that is soluble in aqueous solvents.
  • Such water-soluble polymers include, but are not limited to, polyethylene glycol, polyethylene glycol propionaldehyde, mono C 1 -C 10 alkoxy or aryloxy derivatives thereof (described in U.S. Patent No.5,252,714 which is incorporated by reference herein), monomethoxy-polyethylene glycol, polyvinyl pyrrolidone, polyvinyl alcohol, polyamino acids, divinylether maleic anhydride, N- (2-Hydroxypropyl)-methacrylamide, dextran, dextran derivatives including dextran sulfate, polypropylene glycol, polypropylene oxide/ethylene oxide copolymer, polyoxyethylated polyol, heparin, heparin fragments, polysaccharides, oligosaccharides, glycans, cellulose and cellulose derivatives, including but not limited to methylcellulose and carboxymethyl cellulose, serum albumin, starch and starch derivatives, poly
  • water-soluble polymers may result in changes including, but not limited to, increased water solubility, increased or modulated serum half-life, increased or modulated therapeutic half-life relative to the unmodified form, increased bioavailability, modulated biological activity, extended circulation time, modulated WSGR Ref. No: 31362-826.601 immunogenicity, modulated physical association characteristics including, but not limited to, aggregation and multimer formation, altered receptor binding, altered binding to one or more binding partners, and altered receptor dimerization or multimerization.
  • such water-soluble polymers may or may not have their own biological activity.
  • Antibody-based therapeutics have emerged as important components of therapies for an increasing number of human malignancies in such fields as oncology, immunology, inflammatory and infectious diseases. In most cases, the basis of the therapeutic function is the high degree of specificity and affinity the antibody-based drug has for its target antigen. Arming monoclonal antibodies with drugs, toxins, or radionuclides is yet another strategy by which monoclonal antibodies may induce therapeutic effect. By combining the extraordinarily targeting specificity of antibody with the tumor killing power of toxic effector molecules, immunoconjugates permit sensitive discrimination between target and normal tissue thereby resulting in fewer side effects than most conventional chemotherapeutic drugs. The toxins utilized can specifically, stably and irreversibly conjugate to unique sites in the antibody.
  • ADC Antibodies and Antibody Sequences The present invention provides novel ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence.
  • the present invention provides ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker.
  • the antibody, antibody fragment or variant thereof binds to a tumor-associated antigen (TAA) selected WSGR Ref.
  • TAA tumor-associated antigen
  • the antibody, antibody fragment or variant thereof is TROP2 antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is HER2 antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is HER3 antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is PSMA antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is CD70 antibody, antibody fragment or variant. In other embodiments the invention provides anti-TROP2 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence.
  • the present invention provides anti-TROP2 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker.
  • the invention provides anti-HER2 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence.
  • the present invention provides anti-HER2 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker.
  • the invention provides anti-HER3 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one or more non- natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence.
  • the present invention provides anti-HER3 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one or more non- natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence WSGR Ref.
  • the invention provides anti- PSMA ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence.
  • the present invention provides anti-PSMA ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker.
  • the invention provides anti-CD70 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence.
  • the present invention provides anti-CD70 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker.
  • Antibody or antibody fragments or variants of the disclosure may be human, humanized, engineered, non-human, and/or chimeric antibody or antibody fragments.
  • An antibody or antibody fragment or variant provided herein may comprise two or more amino acid sequences.
  • a first amino acid sequence may comprise a first antibody chain and a second amino acid sequence may comprise a second antibody chain.
  • a first antibody chain may comprise a first amino acid sequence
  • a second antibody chain may comprise a second amino acid sequence.
  • a chain of an antibody may refer to an antibody heavy chain, an antibody light chain, or a combination of a region or all of an antibody heavy chain and a region or all of an antibody light chain.
  • an antibody provided herein comprises a heavy chain or fragment or variant thereof, and a light chain or fragment or variant thereof.
  • Two amino acid sequences of an antibody, including two antibody chains may be connected, attached, or linked by one or more disulfide bonds, a chemical linker, a peptide linker, or a combination thereof.
  • a chemical linker includes a linker via a non-natural amino acid.
  • a chemical linker includes a linker via one or more non-natural amino acids.
  • a chemical linker can include a chemical conjugate.
  • a peptide linker includes any amino acid sequence joining the two amino acid sequences.
  • the peptide linker may comprise 1 or more, 5 or more, 10 or more, 15 or more, 20 or more, 25 or more, 30 or more, 35 or more, 40 or more, 45 or more, 50 or more, 55 or more, 60 or more, 65 or more, 70 or more, 75 or more, 80 or more, 85 or more, 90 or more, 95 or more, 100 or more amino acids.
  • the peptide linker may be a portion of any antibody, including a domain of an antibody, such as a variable domain, CDR1, CDR2, CDR3, and/or a combination of CDRs (complementarity determining regions).
  • a heavy and a light chain are WSGR Ref. No: 31362-826.601 connected, attached, or linked, for example, via a peptide linker.
  • a heavy chain and a light chain are connected, for example, by one or more disulfide bonds.
  • Antibodies, antibody fragments and antibody variants of the disclosure may interact or engage with an antigen on an effector cell.
  • the effector cell can include, but is not limited to, an immune cell, a genetically modified cell having increase or decrease cytotoxic activity, a cell involved in the host defense mechanism, an anti-inflammatory cell, a leukocyte, a lymphocyte, a macrophage, an erythrocyte, a thrombocyte, a neutrophil, a monocyte, an eosinophil, a basophil, a mast cell, a NK cell, a B-cell, or a T-cell.
  • the immune cell may be a T cell such as a cytotoxic T cell or natural killer T cell.
  • the antibody or antibody fragment may interact with a receptor on a T-cell such as, but not limited to a T-cell receptor (TCR).
  • TCR T-cell receptor
  • the TCR may comprise TCR alpha, TCR beta, TCR gamma, and/or TCR delta or TCR zeta.
  • Antibody or antibody fragments of the disclosure may bind to a receptor on a lymphocyte, dendritic cell, B-cell, macrophage, monocytes, neutrophils and/or NK cells.
  • Antibody or antibody fragments of the disclosure may bind to a cell surface receptor.
  • Antibody or antibody fragments of the disclosure may bind to an antigen receptor, such as for example, a TROP2 antigen receptor, or a HER2 antigen receptor, or a CD70 antigen receptor.
  • Antibody or antibody fragments of the disclosure can be conjugated to a T-cell surface antigen.
  • the present disclosure provides novel anti-TROP2 antibodies, anti-HER2 antibodies, anti-HER3 antibodies, anti-PSMA antibodies, anti-CD70 antibodies, or the corresponding antibody fragments, and antibody-drug conjugates thereof for use as therapeutic agents.
  • novel anti-TROP2 antibodies antibody fragments or variants thereof; anti-HER2 antibodies, antibody fragments or variants thereof; anti-HER3 antibodies, antibody fragments or variants thereof; anti-PSMA antibodies, antibody fragments or variants thereof; and anti-CD70 antibodies, antibody fragments or variants thereof; each with at least one non-natural amino acid or unnaturally encoded amino acid.
  • the present invention provides anti-TROP2 antibodies, antibody fragments or variants thereof; anti-HER2 antibodies, antibody fragments or variants thereof; anti-HER3 antibodies, antibody fragments or variants thereof; anti- PSMA antibodies, antibody fragments or variants thereof; and anti-CD70 antibodies, antibody fragments or variants thereof; each having a non-natural amino acid that facilitate antibody conjugation to a drug or drug-linker.
  • Antibodies, antibody fragments or variants provided in the present disclosure may be human, humanized, engineered, non-human, and/or chimeric antibody or antibody fragments that bind to the extracellular domain of the target antigen, which can be overexpressed in a number of cancers.
  • novel antibodies, compositions and antibody drug conjugates for the treatment and/or diagnosis of WSGR Ref. No: 31362-826.601 antigen-expressing cancers are beneficial, including but not limited to TROP2 -expressing cancers, HER2-expressing cancers, HER3-expressing cancers, PSMA-expressing cancers and CD70- expressing cancers.
  • Antibodies or antibody fragments or variants disclosed herein include, but are not limited to, analogs, isoforms, mimetics, fragments, or hybrids of anti-TROP2, anti-HER2, anti-HER3, anti- PSMA and anti-CD70.
  • Antibodies or antibody fragments or variants of anti-TROP2, anti-HER2, anti-HER3, anti-PSMA and anti-CD70 of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • Antibodies comprising non-natural amino acids are also disclosed herein.
  • the antibody or antibody fragments or variants include but are not limited to Fv, Fc, Fab, and (Fab') 2 , single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • the anti-TROP2, or anti-HER2, or anti-HER3, or anti- PSMA, or anti-CD70, antibody or antibody fragments or variants comprises one or more non-natural amino acids.
  • Non-limiting examples of antibodies or antibody fragments or variants of the present disclosure comprise the sequences listed in Tables 1 to 5.
  • antibody or antibody fragments disclosed herein are anti-TROP2 antibodies or antibody fragments or variants thereof.
  • the anti-TROP2 antibodies or antibody fragments or variants disclosed herein can be humanized.
  • Anti-TROP2 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- TROP2 analogs, isoforms, mimetics, fragments, or hybrids.
  • Anti-TROP2 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab') 2 , single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • the anti-TROP2 antibodies or antibody fragments or variants of the present disclosure comprise a sequence of SEQ ID NOs: 1 to 17 (Table 1).
  • the antibodies, fragments or variants of the present disclosure can be an anti-TROP2 antibody, fragment or variant.
  • the anti- TROP2 antibody comprises a heavy chain and light chain amino acid sequence selected from a WSGR Ref. No: 31362-826.601 sequence of SEQ ID NOs: 1 to 17.
  • the anti-TROP2 antibody consists of a heavy chain and light chain amino acid sequence selected from a sequence of SEQ ID NOs: 1 to 17.
  • an anti-TROP2 antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 1.
  • the anti-TROP2 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 1.
  • the anti-TROP2 antibody has an amino acid sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence selected from the group of sequences listed in Table 1.
  • the anti-TROP2 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 5, wherein SEQ ID NO: 5 contains one non-natural amino acid at position 114 based on Kabat numbering.
  • the anti- TROP2 antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 or 17. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 4.
  • At least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 11, wherein SEQ ID NO: 11 contains one non-natural amino acid at position 121.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 5; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 4.
  • an ADC comprising the anti- TROP2 antibody has a drug-to-antibody ratio of about 2.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 5; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 11.
  • an ADC comprising the anti-TROP2 antibody has a drug-to-antibody ratio of about 3 WSGR Ref. No: 31362-826.601 or about 4.
  • each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF).
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 8.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 10. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 12.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 14. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 16.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 7.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID WSGR Ref. No: 31362-826.601 NO: 9. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 11.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 15.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 4.
  • the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 10.
  • the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain WSGR Ref. No: 31362-826.601 amino acid sequence of SEQ ID NO: 15.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 16.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 17.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 3.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 9.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 13.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 17.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises WSGR Ref. No: 31362-826.601 a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 8.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 10. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 12.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 14. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 16.
  • the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 7.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 11.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises two heavy WSGR Ref. No: 31362-826.601 chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 15.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 4.
  • the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 10.
  • the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 14.
  • the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 3.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 4.
  • the WSGR Ref. No: 31362-826.601 anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 7.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 8.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 9.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 13.
  • the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 17.
  • antibody or antibody fragments disclosed herein are anti-CD70 antibodies or antibody fragments or variants thereof.
  • the anti-CD70 antibodies or antibody fragments or variants disclosed herein can be humanized.
  • Anti-CD70 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- CD70 analogs, isoforms, mimetics, fragments, or hybrids.
  • Anti-CD70 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab') 2 , single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • an anti-CD70 antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 2.
  • the anti-CD70 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid WSGR Ref. No: 31362-826.601 sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 2.
  • the anti-CD70 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 20, wherein SEQ ID NO: 20 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti- CD70 antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 19, 21, 22, 23 or 24.
  • At least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 19. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 24, wherein SEQ ID NO: 24 contains one non-natural amino acid at position 121.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 20; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 19. In some embodiments, an ADC comprising the anti-CD70 antibody has a drug-to- antibody ratio of about 2.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 20; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 24.
  • an ADC comprising the anti-CD70 antibody has a drug-to-antibody ratio of about 3 or about 4.
  • each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF).
  • the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 19.
  • the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 23. WSGR Ref. No: 31362-826.601 In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 24.
  • the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 23.
  • the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 24. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 22.
  • the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 23. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 24. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 21.
  • the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 23. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 24. In certain embodiments antibody or antibody fragments disclosed herein are anti-HER2 antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-HER2 antibodies or antibody fragments or variants disclosed herein can be humanized. Anti-HER2 WSGR Ref.
  • antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- HER2 analogs, isoforms, mimetics, fragments, or hybrids.
  • Anti-HER2 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • an anti-HER2 antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 3.
  • the anti-HER2 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 26, wherein SEQ ID NO: 26 contains one non-natural amino acid at position 114 based on Kabat numbering.
  • the anti- HER2 antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 27 or 28. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 27. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 28, wherein SEQ ID NO: 28 contains one non-natural amino acid at position 121.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 26; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 27.
  • an ADC comprising the anti-HER2 antibody has a drug-to- antibody ratio of about 2.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID WSGR Ref. No: 31362-826.601 NO: 26; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 28.
  • an ADC comprising the anti-HER2 antibody has a drug-to-antibody ratio of about 3 or about 4.
  • each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF).
  • the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 25 and a light chain amino acid sequence of SEQ ID NO: 27.
  • the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 25 and a light chain amino acid sequence of SEQ ID NO: 28.
  • the anti-HER2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 25 and two light chain amino acid sequences of SEQ ID NO: 27.
  • the anti-HER2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 25 and two light chain amino acid sequences of SEQ ID NO: 28. In some embodiments, the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 26 and a light chain amino acid sequence of SEQ ID NO: 27. In some embodiments, the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 26 and a light chain amino acid sequence of SEQ ID NO: 28. In some embodiments, the anti-HER2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 26 and two light chain amino acid sequences of SEQ ID NO: 27.
  • the anti-HER2 antibody comprises two heavy chain amino acid sequence of SEQ ID NO: 26 and two light chain amino acid sequences of SEQ ID NO: 28.
  • antibody or antibody fragments disclosed herein are anti-PSMA antibodies or antibody fragments or variants thereof.
  • the anti-PSMA antibodies or antibody fragments or variants disclosed herein can be humanized.
  • Anti-PSMA antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti-PSMA analogs, isoforms, mimetics, fragments, or hybrids.
  • Anti-PSMA antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab') 2 , single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • an anti-PSMA antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 4.
  • the anti-PSMA antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid WSGR Ref. No: 31362-826.601 sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 4.
  • the anti-PSMA antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 36, wherein SEQ ID NO: 36 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti- PSMA antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 37, 39, 41, 43 and 45.
  • At least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 37.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 36; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 37.
  • an ADC comprising the anti-PSMA antibody has a drug- to-antibody ratio of about 2. In some embodiments, an ADC comprising the anti-PSMA antibody has a drug-to-antibody ratio of about 3 or about 4.
  • each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF).
  • the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 37.
  • the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 39.
  • the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 41.
  • the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 43. In some embodiments, the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 45. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 37. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID WSGR Ref. No: 31362-826.601 NO: 36 and two light chain amino acid sequences of SEQ ID NO: 39.
  • the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 41. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 43. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 45. In certain embodiments antibody or antibody fragments disclosed herein are anti-HER3 antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-HER3 antibodies or antibody fragments or variants disclosed herein can be humanized.
  • Anti-HER3 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- HER3 analogs, isoforms, mimetics, fragments, or hybrids.
  • Anti-HER3 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab') 2 , single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like.
  • an anti-HER3 antibody there is provided an anti-HER3 antibody.
  • the anti-HER3 antibody has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 5.
  • the anti-HER3 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 58, wherein SEQ ID NO: 58 contains one non-natural amino acid at position 114 based on Kabat numbering.
  • the anti-HER3 antibody further comprise one or more WSGR Ref. No: 31362-826.601 light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 or 57. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 47. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 51, wherein SEQ ID NO: 51 contains one non-natural amino acid at position 121.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 58; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 47.
  • an ADC comprising the anti-HER3 antibody has a drug-to-antibody ratio of about 2.
  • the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 58; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 51.
  • an ADC comprising the anti-HER3 antibody has a drug-to-antibody ratio of about 3 or about 4.
  • each said non- natural amino acid is para-acetyl-L-phenylalanine (pAF).
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 47.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 48.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 49.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 53.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody WSGR Ref. No: 31362-826.601 comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 57.
  • the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 47. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 48. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 50.
  • the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 54.
  • the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 57. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 47.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 48. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 51.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid WSGR Ref. No: 31362-826.601 sequence of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 55.
  • the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 57. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 47. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 48.
  • the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 52.
  • the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 56.
  • the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 57.
  • Non-limiting examples of antibodies or antibody fragments or variants of the present disclosure include the sequences listed in Tables 1 to 5.
  • Anti-HER2 heavy chain (HC) and light chain (LC) amino acid sequences with amber sites for non-natural amino acid incorporation are also disclosed. Also disclosed are: all of the sequences in Table 3, wherein X is replaced by any non-natural amino acid; all of the sequences in Table 3, wherein any amino acid is replaced by any non-natural amino acid; all of the sequences in Table 3, wherein X is pAF; all of the heavy chain sequences in Table 3, wherein a non-natural amino acid is site specifically incorporated at position 114, according to Kabat numbering, as well known to the skilled artisan; and all of the heavy chain sequences of Table 3, wherein DEL is replaced with EEM.
  • WT Wild Type
  • HC Heavy Chain
  • LC Light Chain
  • X denotes non-natural amino acid.
  • Non-Natural Amino Acids The present disclosure provides antibodies, antibody fragments or variants comprising at least one non-natural amino acid.
  • Introduction of at least one non-natural amino acid into an antibody can WSGR Ref.
  • No: 31362-826.601 allow for the application of conjugation chemistries that involve specific chemical reactions with one or more non-natural amino acids while not reacting with the commonly occurring 20 amino acids.
  • Non-natural amino acid site selection was based on surface exposure/site accessibility within the antibody and hydrophobic or neutral amino acid sites were selected to maintain the charge on the antibody. Methods for introducing non-natural amino acids inserted into sites in a protein are described for example in WO2010/011735 and in WO2005/074650.
  • the non-natural amino acids used in the methods and compositions described herein have at least one of the following four properties: (1) at least one functional group on the sidechain of the non-natural amino acid has at least one characteristics and/or activity and/or reactivity orthogonal to the chemical reactivity of the 20 common, genetically- encoded amino acids (i.e., alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine), or at least orthogonal to the chemical reactivity of the naturally occurring amino acids present in the polypeptide that includes the non-natural amino acid; (2) the introduced non-natural amino acids are substantially chemically inert toward the 20 common, genetically-encoded amino acids; (3) the non
  • Non-natural amino acids may also include protected or masked oximes or protected or masked groups that can be transformed into an oxime group after deprotection of the protected group or unmasking of the masked group.
  • Non-natural amino acids may also include protected or masked carbonyl or dicarbonyl groups, which can be transformed into a carbonyl or dicarbonyl group after deprotection of the protected group or unmasking of the masked group and thereby are available to react with hydroxylamines or oximes to form oxime groups.
  • Oxime-based non-natural amino acids may be synthesized by methods well known in the art, (see for example WO2013/185117 and WO2005/074650), including: (a) reaction of a hydroxylamine-containing non-natural amino acid with a carbonyl- or dicarbonyl-containing reagent; (b) reaction of a carbonyl- or dicarbonyl- WSGR Ref. No: 31362-826.601 containing non-natural amino acid with a hydroxylamine-containing reagent; or (c) reaction of an oxime-containing non-natural amino acid with certain carbonyl- or dicarbonyl-containing reagents.
  • non-naturally encoded amino acid site selection is based on surface exposure.
  • one possible site is an amino acid having a solvent accessible surface area ratio of 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more.
  • one possible site is an amino acid having a solvent accessible surface area ratio of about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 95%, or more.
  • the solvent accessible surface area can be calculated based on the DSSP program [Biopolymers, 22, 2577-2637 (1983)], using a crystalline structure analyzing data file of antibodies or antibody fragments registered in Protein data bank (PDB).
  • the ratio of the solvent accessible surface area of the amino acid residues of interest can be calculated by dividing the antibody structural solvent accessible surface area calculated in the above by the solvent accessible surface area of alanine-X-alanine (X represents the amino acid residues of interest).
  • X represents the amino acid residues of interest.
  • the solvent accessibility of an amino acid can be determined by a solvent accessibility test in which a functional group on the amino acid (a thiol, amino, or carbonyl group) is functionalized when treated with an electrophilic reagent or a nucleophilic reagent, or the like.
  • the functional group i.e., the thiol, amino, or carbonyl group
  • the non-natural amino acid site is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95% solvent accessible.
  • Non-natural amino acids that may be used in the methods and compositions described herein include, but are not limited to, amino acids comprising amino acids with novel functional groups, amino acids that covalently or noncovalently interact with other molecules, glycosylated amino acids such as a sugar substituted serine, other carbohydrate modified amino acids, keto-containing amino acids, aldehyde-containing amino acids, amino acids comprising polyethylene glycol or other polyethers, heavy atom substituted amino acids, chemically cleavable and/or photocleavable amino acids, amino acids with an elongated side chains as compared to natural amino acids, including but not limited to, polyethers or long chain hydrocarbons, including but not limited to, greater than about 5 or greater than about 10 carbons, carbon-linked sugar-containing amino acids, redox-active amino acids, amino thioacid containing amino acids, and amino acids comprising one or more toxic moiety.
  • antibodies comprising one or more non-natural amino acids.
  • the one or more non-natural amino acids may be encoded by a codon that does not code for one of the twenty natural amino acids.
  • the one or more non-natural amino acids may be encoded by a nonsense codon (stop codon).
  • the stop codon may be an amber codon.
  • the amber codon may comprise a UAG sequence.
  • the stop codon may be an ochre codon.
  • the ochre codon may comprise a UAA sequence.
  • the stop codon may be an opal or umber codon.
  • the opal or umber codon may comprise a UGA sequence.
  • Non-natural amino acids may be encoded by a four-base codon.
  • Non-natural amino acids of the present disclosure include, but are not limited to, 1) substituted phenylalanine and tyrosine analogues, such as 4-amino-L-phenylalanine, 4-acetyl-L-phenylalanine, 4-azido-L-phenylalanine, 4-nitro-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-isopropyl-L- phenylalanine, 3-nitro-L-tyrosine, O-methyl-L-tyrosine and O-phosphotyrosine; 2) amino acids that can be photo-cross-linked, e.g., amino acids with aryl azide or benzophenone groups, such as 4- azidophenylalanine or 4-benzoylphenylalanine; 3) amino acids that have unique chemical reactivity, such as 4-acetyl-L-phenylalanine,
  • non-natural amino acids include, but are not limited to, a p-acetylphenylalanine (4-acetyl phenylalanine) (including 4-acetyl-L- phenylalanine, also referred to herein as p-acetyl-L-phenylalanine (pAF)), a 4-boronophenylalanine (pBoF) (e.g., 4-borono-L-phenylalanine, a 4-propargyloxyphenylalanine (pPrF) (e.g., 4- propargyloxy-L-phenylalanine), an O-methyltyrosine (e.g., O-methyl-L-tyrosine), a 3-(2- naphthyl)alanine (NapA) (e.g., 3-(2-naphthyl)-L-alanine), a 3-methylphenylalanine (e.g., 3-methyl- L-phenyla
  • non-natural amino acids are disclosed in Liu et al. (2010) Annu Rev Biochem, 79:413-44; Wang et al. (2005) Angew Chem Int Ed, 44:34-66; and Published International Application Nos.: WO 2012/166560, WO 2012/166559, WO 2011/028195, WO 2010/037062, WO 2008/083346, WO 2008/077079, WO 2007/094916, WO 2007/079130, WO 2007/070659 and WO 2007/059312, the entire contents of each of which are hereby incorporated by reference herein in their entirety.
  • the one or more non-natural amino acids can be p- acetylphenylalanine.
  • the one or more non-natural amino acids can be p-acetyl-L-phenylalanine (pAF).
  • one or more non-natural amino acids is selected from the group Acetyl-D-glucosaminyl)asparagine, O-allyltyrosine, alpha-N-acetylgalactosamine-O-serine, alpha- N-acetylgalactosamine-O-threonine, 2-aminooctanoic acid, 2-aminophenylalanine, 3- aminophenylalanine, 4-aminophenylalanine, 2-aminotyrosine, 3-aminotyrosine, 4- azidophenylalanine, 4-benzoylphenylalanine, (2,2-bipyridin-5yl)alanine, 3-boronophenylalanine, 4- boronophenylalanine, 4-bromophenylalanine, p-carbox
  • one or more non-natural amino acids is selected from the group consisting of 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)), 3-O-(N-acetyl-beta-D- alpha-N-acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2- aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L-tyrosine, 3-amino-L-tyrosine, 4-azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin-5yl)-L-alanine, 3-borono-L-phenylalanine, 4-boron
  • the one or more non-natural amino acids can be p-acetyl-L- phenylalanine (pAF).
  • pAF p-acetyl-L- phenylalanine
  • each and every one of the one or more non- natural amino acids is pAF.
  • an antibody with at least one non-natural amino acid includes at least one post-translational modification.
  • the at least one post- translational modification comprises attachment of a molecule including but not limited to, a water- WSGR Ref.
  • soluble polymer a derivative of polyethylene glycol, a drug, a second protein or polypeptide or polypeptide analog, an antibody or antibody fragment, a biologically active agent, a small molecule, or any combination of the above or any other desirable compound or substance, comprising a second reactive group to at least one non-natural amino acid comprising a first reactive group utilizing chemistry methodology that is known to one of ordinary skill in the art to be suitable for the particular reactive groups.
  • the first reactive group is an alkynyl moiety (including but not limited to, the non-natural amino acid p-propargyloxyphenylalanine, where the propargyl group is also sometimes referred to as an acetylene moiety) and the second reactive group is an azido moiety, and [3+2] cycloaddition chemistry methodologies are utilized.
  • the first reactive group is the azido moiety (including but not limited to, the non-natural amino acid p-azido-L- phenylalanine) and the second reactive group is the alkynyl moiety.
  • At least one non-natural amino acid comprising at least one post-translational modification
  • the at least one post-translational modification comprises a saccharide moiety.
  • the post-translational modification is made in vivo in a eukaryotic cell or in a non-eukaryotic cell.
  • the post-translational modification is made in vitro.
  • the post-translational modification is made in vitro and in vivo.
  • the non-natural amino acid may be modified to incorporate a chemical group.
  • the non-natural amino acid may be modified to incorporate a ketone group.
  • the one or more non-natural amino acids may comprise at least one oxime, carbonyl, dicarbonyl, hydroxylamine group or a combination thereof.
  • the one or more non-natural amino acids may comprise at least one carbonyl, dicarbonyl, alkoxy-amine, hydrazine, acyclic alkene, acyclic alkyne, cyclooctyne, aryl/alkyl azide, norbornene, cyclopropene, trans-cyclooctene, or tetrazine functional group or a combination thereof.
  • the non-natural amino acid is site-specifically incorporated into the antibody, antibody fragment or variant. In some embodiments the non-natural amino acid is site-specifically incorporated into an antibody, antibody fragment or variant.
  • Methods for incorporating a non-natural amino acid into a molecule for example, proteins, polypeptides or peptides, are disclosed in U.S. Patent Nos.: 7,332,571; 7,928,163; 7,696,312; 8,008,456; 8,048,988; 8,809,511; 8,859,802; 8,791,231; 8,476,411; or 9,637,411, (each of which is incorporated herein by reference in its entirety), and in the Examples herein.
  • the one or more non-natural amino acids may be incorporated by methods known in the art.
  • cell-based or cell-free systems may be used, and auxotrophic strains may also be used in place of engineered tRNA and synthetase.
  • auxotrophic strains may also be used in place of engineered tRNA and synthetase.
  • orthogonal tRNA synthetase are used as disclosed in for example, WO2002085923A2; WO2002086075A2; WO2004035743A2; WO2007021297A1; WO2006068802A2; and WO2006069246A2; the contents of each of which are incorporated herein by reference in their entirety.
  • Incorporating one or more non-natural amino acids into the antibody or antibody fragment or variant may comprise modifying one or more amino acid residues in the antibody or antibody fragment or variant. Modifying the one or more amino acid residues in the antibody or antibody fragment or variant may comprise mutating one or more nucleotides in the nucleotide sequence encoding the antibody or antibody fragment or variant. Mutating the one or more nucleotides in the nucleotide sequence encoding the antibody or antibody fragment or variant may comprise altering a codon encoding an amino acid to a nonsense codon.
  • Incorporating one or more non-natural amino acids into the antibody or antibody fragment or variant may comprise modifying one or more amino acid residues in the antibody or antibody fragment or variant to produce one or more amber codons in the antibody or antibody fragment or variant.
  • the one or more non-natural amino acids may be incorporated into the antibody or antibody fragment or variant in response to an amber codon.
  • the one or more non-natural amino acids may be site-specifically incorporated into the antibody or antibody fragment or variant.
  • Incorporating one or more non-natural amino acids into the antibody or antibody fragment or variant may comprise one or more genetically encoded non-natural amino acids with orthogonal chemical reactivity relative to the canonical twenty amino acids to site- specifically modify the biologically active molecule or targeting agent.
  • the twenty canonical amino acids are alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine.
  • Incorporating the one or more non-natural amino acids may comprise use of a tRNA/aminoacyl-tRNA synthetase pair to site- specifically incorporate one or more non-natural amino acids at defined sites in the biologically active molecule or targeting agent in response to one or more amber nonsense codon.
  • Additional methods for incorporating non-natural amino acids include, but are not limited to, methods disclosed in Chatterjee et al., A Versatile Platform for Single- and Multiple-Unnatural Amino Acid Mutagenesis in Escherichia coli, Biochemistry, 2013; Kazane et al., J Am Chem Soc, 135(1):340-6, 2013; Kim et al., J Am Chem Soc, 134(24):9918-21, 2012; Johnson et al., Nat Chem Biol, 7(11):779-86, 2011; and Hutchins et al., J Mol Biol, 406(4):595-603, 2011.
  • the one or more non-natural amino acids may be produced through selective reaction of one or more natural amino acids.
  • the selective reaction may be mediated by one or more enzymes.
  • the selective reaction of one or more cysteines with formylglycine generating enzyme (FGE) may produce one or more formylglycines as described in Rabuka et al., Nature Protocols 7: 1052-1067, 2012.
  • the one or more non-natural amino WSGR Ref. No: 31362-826.601 acids may involve a chemical reaction to form a linker.
  • the chemical reaction to form the linker may include a bioorthogonal reaction.
  • the chemical reaction to form the linker may include click chemistry. See for example WO2006/050262 incorporated herein by reference in its entirety.
  • Any position of the antibody or antibody fragment is suitable for selection to incorporate a non-natural amino acid, and selection may be based on rational design or by random selection for any or no particular desired purpose. Selection of desired sites may be based on producing a non- natural amino acid polypeptide (which may be further modified or remain unmodified) having any desired property or activity, including but not limited to a receptor binding modulators, receptor activity modulators, modulators of binding to binder partners, binding partner activity modulators, binding partner conformation modulators, dimer or multimer formation, no change to activity or property compared to the native molecule, or manipulating any physical or chemical property of the polypeptide such as solubility, aggregation, or stability.
  • the sites identified as critical to biological activity may also be good candidates for substitution with a non-natural amino acid, again depending on the desired activity sought for the polypeptide.
  • Another alternative would be to simply make serial substitutions in each position on the polypeptide chain with a non-natural amino acid and observe the effect on the activities of the polypeptide. Any means, technique, or method for selecting a position for substitution with a non-natural amino acid into any polypeptide is suitable for use in the methods, techniques and compositions described herein.
  • the structure and activity of naturally-occurring mutants of a polypeptide that contain deletions can also be examined to determine regions of the protein that are likely to be tolerant of substitution with a non-natural amino acid.
  • non-natural amino acids can be determined by the skilled person.
  • exemplary sites of incorporation of a non-natural amino acid include, but are not limited to, those that are excluded from potential receptor binding regions, or regions for binding to binding proteins or ligands may be fully or partially solvent exposed, have minimal or no hydrogen-bonding WSGR Ref. No: 31362-826.601 interactions with nearby residues, may be minimally exposed to nearby reactive residues, and/or may be in regions that are highly flexible as predicted by the three-dimensional crystal structure of a particular polypeptide with its associated receptor, ligand or binding proteins
  • a wide variety of non-natural amino acids can be substituted for, or incorporated into, a given position in a polypeptide.
  • a particular non-natural amino acid may be selected for incorporation based on an examination of the three-dimensional crystal structure of a polypeptide with its associated ligand, receptor and/or binding proteins, a preference for conservative substitutions.
  • Linkers In some aspects, the present disclosure relates to linkers for intracellular delivery of drug conjugates. Many procedures and linker molecules for attachment of various compounds to peptides are known. See, for example, European Patent Application No.0188256; U.S. Patent Nos.4,671,958, 4,659,839, 4,414,148, 4,699,784, 4,680,338, 4,569,789 and 10,550,190; PCT Application Publication Nos.
  • the present disclosure relates to phosphate-based linkers for intracellular delivery of drug conjugates (see, e.g., U.S. patent no.10,550,190).
  • the phosphate-based linkers of the present disclosure include a monophosphate, diphosphate, triphosphate, or tetraphosphate group (phosphate group) and a linker arm and optionally a spacer.
  • a drug-linker can be covalently linked to a reactive functional group that can be covalently linked to a cell-specific targeting ligand such as an antibody or antibody fragment.
  • Phosphate-based linkers have a differentiated and tunable stability in blood compared to the intracellular environment (e.g. lysosomal compartment).
  • ADCs comprising these phosphate-based linkers are stable in circulation (plasma/blood) but reactive or cleavable in intracellular compartments (lysosome) making them useful for intracellular delivery of drug conjugates.
  • the phosphate-based linker is capable of being conjugated to a drug and the reactive functional group is capable of being conjugated to a cell-specific targeting ligand such as an anti-TROP2 antibody, an anti-HER2 antibody, an anti-CD70 antibody, an anti-HER3 antibody or an anti-PSMA antibody.
  • the phosphate-based linkers of the present disclosure are designed to engineer ADCs such that the likelihood of the conjugate to form aggregates is reduced compared to conjugates in which the same drug is conjugated to the antibody or targeting ligand using a linker that is not a phosphate-based linker. Further, the phosphate-based linker design, WSGR Ref.
  • Linkers may be designed de novo, including by way of example only, as part of high-throughput screening process (in which case numerous polypeptides may be designed, synthesized, characterized and/or tested) or based on the interests of the researcher.
  • the linker may also be designed based on the structure of a known or partially characterized polypeptide. The principles for selecting which amino acid(s) to substitute and/or modify and the choice of which modification to employ are described in WO2013/185117, for example. Linkers may be designed to meet the needs of the experimenter or end user.
  • Such needs may include, but are not limited to, manipulating the therapeutic effectiveness of the polypeptide, improving the safety profile of the polypeptide, adjusting the pharmacokinetics, pharmacologics and/or pharmacodynamics of the polypeptide, such as, by way of example only, increasing water solubility, bioavailability, increasing serum half-life, increasing therapeutic half- life, modulating immunogenicity, modulating biological activity, or extending the circulation time.
  • modifications include, by way of example only, providing additional functionality to the polypeptide, incorporating an antibody, and any combination of the aforementioned modifications.
  • a linker of the present disclosure can be a unit that is combinable with one or more additional units, such that the combined linker units can bond to one or more drugs.
  • Each linker unit can be comprised of one or more moieties, each of which may occur one or more times.
  • a linker of the present disclosure comprises at least one phosphate- based moiety, as disclosed herein.
  • the linker comprises the phosphate-based moiety and further comprises at least one moiety or unit that is not phosphate-based.
  • the linker is a bivalent linker.
  • the linker is a trivalent linker.
  • the linker is a tetravalent linker.
  • the present disclosure provides for phosphate-based linkers.
  • a phosphate-based linker of the present disclosure can comprise a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate and/or a diphosphorthioate.
  • a phosphate-based linker of the present disclosure can comprise: a phosphate ester having the structure ; WSGR Ref.
  • a phosphate-based linker of the present disclosure is chiral.
  • a phosphate-based linker of the present disclosure comprises a phosphate-based moiety selected from the group consisting of a pyrophosphate ester and a diphosphonate.
  • a phosphate-based linker of the present disclosure can be synthesis according to Schemes A and B below.
  • Scheme A two monophosphate analogues react with each other under a coupling reaction condition to make the pyrophosphate analogues bearing a reactive group (RG). RG then can be used to react with L2- or L3-L2-containing reagents leading to compounds of Formula (I), wherein L2 and L3 are as defined according to Formula (I) disclosed herein.
  • RG is an L2 or L3-L2-containing groups that can react with an antibody; wherein L2 and L3 are as defined according to Formula (I) disclosed herein.
  • Scheme A Reactions routes relying on a coupling reaction to make pyrophosphate analogs
  • Scheme B WSGR Ref. No: 31362-826.601
  • a phosphate-based linker of the present disclosure further comprises at least one additional moiety.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, – (alkylene–O) nn –, optionally substituted arylene, -O-, -C(O)-, -N(R w )-, -S(O) 0-2 - and an amino acid, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C 1 -C 8 alkyl; and combinations thereof.
  • each arylene is phenylene.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and - N(Rw)-, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C 1 -C 8 alkyl; and combinations thereof. In some embodiments, each R w is independently H or methyl.
  • a phosphate-based linker of the present disclosure consists of a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(R w )- and an amino acid; wherein each nn is independently an integer from 1 to 100; WSGR Ref. No: 31362-826.601 wherein each R w is independently H or C 1 -C 8 alkyl; and combinations thereof.
  • each Rw is independently H or methyl.
  • a phosphate-based linker of the present disclosure is a linker selected from the group of linkers listed in Table 6. Table 6.
  • WSGR Ref. No: 31362-826.601 WSGR Ref. No: 31362-826.601
  • each alkylene of Table 6 is independently –(CH 2 )–, –(CH 2 ) 2 – or – (CH2)3–.
  • each nn of Table 6 is independently 1, 2 or 3.
  • each i of Table 6 is 1. In some other embodiments, each i of Table 6 is 0.
  • a phosphate-based linker of the present disclosure is a linker selected from the group of linkers listed in Table 7. Table 7.
  • Table 7. Non-limiting examples of linkers of the present disclosure.
  • WSGR Ref. No: 31362-826.601 In some embodiments, each alkylene of Table 7 is independently –(CH2)–, –(CH2)2– or – (CH2)3–.
  • each n of Table 7 is independently 1, 2 or 3.
  • each i of Table 7 is 1.
  • WSGR Ref. No: 31362-826.601 In some other embodiments, each i of Table 7 is 0.
  • a phosphate-based linker of the present disclosure is a linker selected from the group of linkers listed in Table 8.
  • each alkylene of Table 8 is independently –(CH2)–, –(CH2)2– or – (CH 2 ) 3 –.
  • each n of Table 8 is independently 1, 2 or 3.
  • each i of Table 8 is 0.
  • each i of Table 8 is 1.
  • i is 1.
  • i is 1.
  • i is 1. In some embodiments, n is 2. In some embodiments, m is 1, 2 or 3. In some embodiments, a phosphate-based linker of the present disclosure is selected from the group consisting of: WSGR Ref. No: 31362-826.601 wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to drug; and each + denotes connection to a reactive moiety. In some further embodiments, each m is independently 1, 2 or 3; each n independently 1, 2 or 3; and each q is independently 1, 2 or 3. In some embodiments, i is 1.
  • i is 0.
  • L is joined to a bivalent oxygen atom of the drug (e.g., the oxygen of a hydroxyl group).
  • a phosphate-based linker of the present disclosure is connected to a drug and is also connected to a reactive moiety.
  • the linker bridges the drug and the reactive moiety.
  • the reactive moiety can be one that can react with another moiety of a natural amino acid or non-natural amino acid of a polypeptide, such as an antibody, antibody fragment or variant thereof of the present disclosure, as disclosed herein.
  • a phosphate-based linker as disclosed herein is connected to a drug, and is also connected to an antibody, antibody fragment or variant thereof, via a linkage or adduct moiety.
  • the linker bridges the drug and the antibody, antibody fragment or variant thereof.
  • Drugs and Drug-Linkers In some aspects, the present disclosure provides a drug or drug-linker, wherein the drug is a cytotoxic drug or agent.
  • the cytotoxic drug is exatecan, an exatecan derivative or exatecan analog.
  • the drug or drug-linker is a drug or drug-linker generated as described in the Examples herein, wherein the linker, when present, can be derivatized with a reactive or other moiety; or a metabolite thereof.
  • the cytotoxic drug is exatecan, having the following structure: or a salt thereof.
  • the present disclosure provides a compound of Formula (VII) or (VIII): or ; WSGR Ref. No: 31362-826.601 wherein: L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety; or a pharmaceutically acceptable salt thereof.
  • L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a te
  • the compound is a compound of Formula (VII): .
  • the compound is a compound of Formula (VIII): .
  • the reactive moiety W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, - C(O)ORd, -C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein R b is H or unsubstituted alkyl, R c is unsubstituted alkyl, and Rd is H, unsubstituted alkyl or a carboxylic acid protecting group.
  • the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. In some more particular embodiments, the phosphate-based moiety is a pyrophosphate ester. In some embodiments, in addition to the phosphate-based moiety, L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the WSGR Ref.
  • No: 31362-826.601 group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O) nn –, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof.
  • arylene is phenylene.
  • each R w is independently H or methyl.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –, -O-, -C(O)- and -N(R w )-, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, each Rw is independently H or methyl.
  • reactive moiety W is selected from the group consisting of: -OH, -SH, -NHR b , -C(O)R c , -C(O)OR d , an activated ester, –O–NH 2 and an optionally substituted monocyclic or polycyclic group comprising a cyclooctyne; wherein: R b is H or unsubstituted C 1 -C 6 alkyl, R c is unsubstituted C 1 -C 6 alkyl, Rd is H, unsubstituted C1-C6 alkyl or a carboxylic acid protecting group, Rf is H or unsubstituted C1-C6 alkyl, s is 0, 1, 2, 3, 4, 5 or 6, and t is 0, 1, 2, 3, 4, 5 or 6.
  • the optionally substituted monocyclic or polycyclic group comprising the cyclooctyne is selected from the group consisting of: , .
  • W is -ONH2.
  • the linker L that is joined to W consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and WSGR Ref.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(Rw)- and an amino acid; wherein each nn is independently an integer from 1 to 100; wherein each R w is independently H or C 1 -C 8 alkyl; and combinations thereof; optionally, each R w is independently H or methyl.
  • the phosphate-based moiety is a pyrophosphate ester.
  • L is selected from the group consisting of the linkers listed in Table 6.
  • the drug-linker when the drug-linker is a compound of Formula (VII), then *, when present, denotes the connection to the -N(H) of Formula (VII). In other embodiments, when the drug-linker is a compound of Formula (VIII), then *, when present, denotes the connection to the -O of Formula (VIII). In some embodiments, W is -ONH 2 . In some further embodiments, L is selected from the group consisting of the linkers listed in Table 7. In some embodiments, when the drug-linker is a compound of Formula (VII), then * denotes the connection to the -N(H) of Formula (VII).
  • the drug-linker when the drug-linker is a compound of Formula (VIII), then * when denotes the connection to the -O of Formula (VIII). In some embodiments, W is -ONH 2 . In yet some further embodiments, L is selected from the group consisting of the linkers listed in Table 8. In some embodiments, when the drug-linker is a compound of Formula (VII), then * denotes the connection to the -N(H) of Formula (VII). In other embodiments, when the drug-linker is a compound of Formula (VIII), then * when denotes the connection to the -O of Formula (VIII). In some embodiments, W is -ONH 2 .
  • each alkylene of Table 6, Table 7 or Table 8 is independently –(CH2)– , –(CH 2 ) 2 – or –(CH 2 ) 3 –;.
  • each n of Table 6, Table 7 or Table 8 is independently 1, 2 or 3.
  • L has the following structure: wherein: n is an integer from 1 to 10; q is an integer from 1 to 10; i is 0 or 1; WSGR Ref. No: 31362-826.601 * denotes the connection to drug; and + denotes connection to a reactive moiety.
  • i is 1.
  • q is 1.
  • n is 2.
  • L has the following structure: wherein: m is an integer from 1 to 10; n is an integer from 1 to 10; q is an integer from 1 to 10; i is 0 or 1; * denotes the connection to drug; and + denotes connection to a reactive moiety.
  • i is 1.
  • n is 2.
  • m is 1, 2 or 3.
  • -L-W is selected from the group consisting of: WSGR Ref. No: 31362-826.601 ; each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to drug; and each wavy line denotes connection to a reactive moiety. In some further embodiments, each m is independently 1, 2 or 3; each n independently 1, 2 or 3; and each q is independently 1, 2 or 3. In some embodiments, W is -ONH2. In some embodiments, i is 1. In some other embodiments, i is 0.
  • the compound when * occurs at a carbonyl (-C(O)-) of -L-W, then the compound is a compound of Formula (VII), and the carbonyl of L-W is joined to NH of the compound of Formula (VII).
  • the compound of Formula (VII) is: or a pharmaceutically acceptable salt thereof.
  • the compound of Formula (VIII) is: WSGR Ref. No: 31362-826.601 or a pharmaceutically acceptable salt thereof.
  • present disclosure provides a compound of Formula (II):
  • Drug has the following structure: n is independently 1 or 2; each Y is independently O, N(R w ) or CH 2 ; wherein each R w is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH 2 ) m , * CH 2 -O-(CH 2 ) m , * (CH 2 ) m -O-CH 2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C 1 -C 3 alkyl, hydroxy, NH 2 , and C 1 -C 3 alkoxy, C 3 -C 6
  • L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH 2 ) q O )((CH 2 ) r O ), [*] NHCH((CH 2 ) q )((CH 2 ) r O ), [*] NHCH((CH 2 ) q )((CH 2 ) r O ), [*] NHCH((CH 2 ) q C(O) )((CH 2 ) r O ), [*] NHCH((CH 2 ) q C(O) )((CH 2 ) r ), [*] NHCH((CH 2 ) q C(O) )((CH 2 ) r ), [*] NHCH((CH 2 ) q C(O) )((CH 2 ) r ), [*] NHCH((CH 2 ) q C(O) )((CH 2 ) r ), [*]
  • Drug is: WSGR Ref. No: 31362-826.601 . In other embodiments, Drug is: .
  • a compound of Formula (II) wherein n is 1.
  • X and Y are O.
  • L1 and L2 are absent.
  • L3 is H2N-O-(CH2)s , wherein s is 1, 2, 3, 4, 5 or 6.
  • s is 1, 2 or 3. In some embodiments, s is 2.
  • Linker is O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**] or O-CH2-O-C(O) [**], wherein v is 2, 3, 4, 5 or 6.
  • Linker is O-CH2 [**] or O-CH2-O-C(O) [**].
  • Drug is: Linker is O-(CH2)v-O-C(O) [**], wherein v is 1, 2, 3, 4, 5 or 6.
  • v is 1.
  • Drug is: WSGR Ref. No: 31362-826.601 Linker is O-(CH2)v [**], wherein v is 1, 2, 3, 4, 5 or 6.
  • v is 1.
  • the compound of Formula (II) is: In some other embodiments, there is provided a compound of Formula (II) wherein n is 2. In some embodiments, X and Y are O. In some embodiments, there is provided a compound of Formula (IIa):
  • Y is O; each L1 is * (OCH 2 CH 2 ) m , wherein each m is independently 1, 2, 3, 4, 5 or 6, and * denotes connection to L 2b ; L 2b is: , wherein [*] denotes connection to L3 and each Z1 is independently C(H) or N; L3 is H2N-O-(CH2)s-C(O)-NH , H2N-O-(CH2)s-C(O) , H2N-O-(CH2)s , H2N-O-(CH2)s-O or H2N-O-(CH2CH2O)s-CH2CH2C(O) ; and each Linker is O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**] or O-CH2-O- C(O) [**], wherein each v is 2, 3, 4, 5 or 6.
  • the compound of Formula (IIa) is: WSGR Ref. No: 31362-826.601 or a pharmaceutically acceptable salt thereof. In some other embodiments, the compound of Formula (IIa) is: or a pharmaceutically acceptable salt thereof. In some other aspects, the present disclosure provides a compound of Formula (III): wherein: Drug has the following structure: WSGR Ref.
  • each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof.
  • Drug has the following structure: .
  • Drug has the following structure: .
  • the present disclosure provides a compound of Formula (IV): each p is independently 0, 1, 2, 3, 4, 5, 6, 7, 8, 910, or p is an integer greater than 10; each Y is independently O, N(R w ) or CH 2 ; wherein each R w is independently H or unsubstituted alkyl; each X is independently O or S; WSGR Ref.
  • each L1 is independently absent, * (CH 2 ) m , * CH 2 -O-(CH 2 ) m , * (CH 2 ) m -O-CH 2 , * C(O)-(CH 2 ) m , * NH-(CH 2 ) m , * (CH 2 ) m (OCH 2 CH 2 ) k , * NH-(CH 2 ) m (OCH 2 CH 2 ) k , unsubstituted C 1 -C 6 alkylene, C 1 -C 6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6, and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is
  • each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof.
  • Drug has the following structure: .
  • Drug has the following structure: .
  • Table 9 provides exemplary drug-linker compounds that can be employed or conjugated with any targeting ligand such as an antibody or antibody fragment, that is selected based in its specificity for an antigen expressed on a target cell or at a target site of interest.
  • the drug-linkers of the invention can be employed with antibody or antibody fragments to a variety of antigens including but not limited to tumor associated antigens, tumor specific antigens, cancer antigens or diseases specific antigens.
  • antigens include PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD4, CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD37, CD38, CD40L, CD44, CD46, CD47, CD48, CD52, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD80, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD163, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7- H3), CTLA4, integrins, mesothe
  • drug-linker compounds disclosed in Table 9 can be employed with anti-HER2 antibody, antibody fragments or antibody drug conjugates of the invention.
  • drug-linker compounds disclosed in Table 9 can be employed with an anti-HER3 antibody, antibody fragments or antibody drug conjugates of the present disclosure.
  • drug-linker compounds disclosed in Table 9 can be employed with anti-CD70 antibody, antibody fragments or antibody drug conjugates of the invention.
  • drug-linker compounds disclosed in Table 9 can be employed with anti-PSMA antibody, antibody fragments or antibody drug conjugates of the invention.
  • drug-linker compounds disclosed in Table 9 can be employed with an anti-TROP2 antibody, antibody fragments or antibody drug conjugates of the present disclosure.
  • Table 9. Non-limiting Drug-linker Compounds of the Invention WSGR Ref. No: 31362-826.601
  • the present invention provides additional drug-linkers prepared using similar procedures as described herein, including the schemes disclosed in the Examples. Additional drug-linker compounds are engineered by linkage of any possible linker group known in the art or elsewhere.
  • the drug-linker compounds are engineered by linkage of one or more phosphate-based linkers via any chemical or functional reactive positions in the drug, for example a nitrogen, halogen, boron, phosphorus, silicon, carbon or oxygen of the cytotoxic agent.
  • drug-linkers of the invention include a phosphate-based linker attached or linked at a hydroxyl group of the cytotoxic agent or analogue thereof, such as a topoisomerase inhibitor.
  • drug-linkers of the invention include a phosphate-based linker attached or linked at a methyl or methylene group of the cytotoxic agent or analogue thereof.
  • such additional drug-linker compounds can comprise a branched linker, which connects to two identical or different drugs.
  • drug-linkers of the present invention include drug- linkers generated via linkage of one or more phosphate-based linkers at one or more a nitrogen, halogen, boron, phosphorus, silicon, sulfur, carbon, or oxygen of the cytotoxic agent.
  • a drug linker compound containing a reactive moiety is conjugated to an antibody or antibody fragment by reacting a drug-linker compound with an antibody, antibody fragment or variant thereof (or simply “antibody”) containing one or more natural or non-natural amino acids.
  • the conjugation reaction provides an ADC, wherein drug-linker is conjugated to a natural or non-natural amino acid of the antibody via a covalent linkage.
  • the covalent linkage can be a product of the reactive moiety of the drug-linker and an additional moiety present in the natural or non-natural amino acid, wherein the additional moiety can react to form the covalent linkage with the reactive moiety.
  • Non-limiting examples of reactions and linkages formed between drug-linker compounds and natural or non-natural amino acids incorporated into an antibody of the present disclosure include the following.
  • A. (i) Reaction of a drug-linker comprising -N 3 with a non-natural amino acid comprising an alkynyl group, thereby providing a linkage comprising a 4,5-dihydro-1,2,3-triazolyl moiety; or (ii) reaction of a drug-linker comprising an alkynyl group with a non-natural amino acid comprising -N 3 , thereby providing a linkage comprising a 4,5-dihydro-1,2,3-triazolyl moiety.
  • the alkynyl group is a cyclooctynyl group.
  • the non-natural amino acid is p-azido-L-phenylalanine.
  • the linkage comprising the 4,5- dihydro-1,2,3-triazolyl moiety has the following structure: ; wherein: each s is independently 0 or an integer from 1 to 50; optionally, each s is independently 0, 1, 2, 3, 4, 5 or 6; each t is independently 0 or an integer from 1 to 50; optionally, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody.
  • the linkage comprising the 1,4- dihydropyridazinyl moiety has the following structure: wherein: each R f is independently H or alkyl, optionally unsubstituted C 1 -C 6 alkyl; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. C.
  • the carbonyl or ketone group is -C(O)R c , wherein R c is unsubstituted C 1 -C 6 alkyl. In some embodiments, R c is methyl.
  • the linkage comprising the oxime moiety has the following structure: wherein: each R c is independently unsubstituted C1-C6 alkyl; optionally, each R c is methyl; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. D.
  • No: 31362-826.601 sulfaneyl)pyrrolidine-2,5-dione moiety has the following structure: wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody.
  • a drug-linker comprising a primary or secondary amine Reaction of a drug-linker comprising a primary or secondary amine with a natural or non-natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising an amide moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a natural or non-natural amino acid comprising a primary or secondary amine group, thereby providing a linkage comprising a amide moiety.
  • the natural amino acid is aspartic acid or glutamic acid. In some other embodiments, the natural amino acid is lysine.
  • the reaction is a peptide coupling reaction or other well-known method of forming an amide, each of which can be performed using methods readily understood by a person of ordinary skill in the art.
  • the linkage comprising the amide moiety has the following structure: wherein: each R b is independently H or alkyl; optionally unsubstituted C1-C6 alkyl; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. F.
  • a drug-linker comprising a hydroxyl group (-OH) Reaction of a drug-linker comprising a hydroxyl group (-OH) with a natural or non- natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising an ester moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a natural or non-natural amino acid comprising a hydroxyl group (-OH), thereby providing a linkage comprising an ester moiety.
  • the natural amino acid is aspartic acid or glutamic acid.
  • the natural amino acid is serine, threonine or tyrosine.
  • Methods of forming such esters linkages can be performed using methods readily understood by a person of WSGR Ref. No: 31362-826.601 ordinary skill in the art.
  • the linkage comprising the ester moiety has the following structure: wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. G.
  • a drug-linker comprising a thiol group (-SH) Reaction of a drug-linker comprising a thiol group (-SH) with a natural or non-natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising a thioester moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a natural or non-natural amino acid comprising a thiol group (-SH), thereby providing a linkage comprising a thioester moiety.
  • the natural amino acid is aspartic acid or glutamic acid.
  • the natural amino acid is cysteine.
  • Methods of forming such thioesters linkages can be performed using methods readily understood by a person of ordinary skill in the art.
  • the linkage comprising the ester moiety has the following structure: wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. H.
  • the natural amino acid is aspartic acid or glutamic acid. Methods of forming such linkages can be performed using methods readily understood by a person of ordinary skill in the art.
  • the linkage has the following structure: WSGR Ref. No: 31362-826.601 wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody.
  • each + denotes connection to a linker of the drug-linker
  • each wavy line denotes connection to the antibody.
  • I Reaction of a drug-linker comprising a thiol group (-SH) with a natural or non-natural amino acid comprising a thiol group, thereby providing a linkage comprising a disulfide.
  • the natural amino acid is cysteine.
  • disulfide linkages can be performed using methods readily understood by a person of ordinary skill in the art.
  • the present disclosure provides drug moieties with linkers that reduce the toxicity of the moiety in vivo while retaining pharmacological activity.
  • the toxicity of the linked drug when administered to an animal or human, is reduced or eliminated compared to the free toxic group or toxic group derivatives comprising labile linkages, while retaining pharmacological activity.
  • increased doses of the linked toxic group may be administered to animals or humans with greater safety.
  • the non-natural amino acid polypeptides linked to a drug moiety e.g., exatecan or an exatecan derivative or analog
  • the non-natural amino acid polypeptides linked to a drug moiety are efficacious and less toxic compared to the free drug moiety.
  • at least one post-translational modification at some position on the polypeptide may occur.
  • the co-translational or post-translational modification occurs via the cellular machinery (e.g., glycosylation, acetylation, acylation, lipid-modification, palmitoylation, palmitate addition, phosphorylation, glycolipid-linkage modification, and the like), in many instances, such cellular-machinery-based co-translational or post-translational modifications occur at the naturally occurring amino acid sites on the polypeptide, however, in certain embodiments, the cellular-machinery-based co-translational or post-translational modifications occur on the non- natural amino acid site(s) on the polypeptide.
  • the post-translational modification does not utilize the cellular machinery, but the functionality is instead provided by attachment of a molecule (a polymer; a water- soluble polymer; a derivative of polyethylene glycol; a second protein or polypeptide or polypeptide analog; an antibody or antibody fragment; and any combination thereof) comprising a second reactive group to the at least one non-natural amino acid comprising a first reactive group (including but not limited to, non-natural amino acid containing a ketone, aldehyde, acetal, hemiacetal, alkyne, cycloalkyne, azide, oxime, or hydroxylamine functional group) utilizing chemistry methodology described herein, or others suitable for the particular reactive groups.
  • a molecule a polymer; a water- soluble polymer; a derivative of polyethylene glycol; a second protein or polypeptide or polypeptide analog; an antibody or antibody fragment; and any combination thereof
  • a second reactive group comprising a second reactive group to the at least one
  • the co- translational or post-translational modification is made in vivo in a eukaryotic cell or in a non- eukaryotic cell.
  • the post-translational modification is made in vitro not WSGR Ref. No: 31362-826.601 utilizing the cellular machinery. Also included with this aspect are methods for producing, purifying, characterizing and using such a drug-linker containing at least one such co-translationally or post- translationally modified non-natural amino acids.
  • compositions, strategies and techniques described herein are reagents capable of reacting with a drug-linker (containing a carbonyl or dicarbonyl group, alkyne, cycloalkyne, azide, hydroxylamine group, or masked or protected forms thereof) that is part of a polypeptide so as to produce any of the aforementioned post-translational modifications.
  • a drug-linker containing a carbonyl or dicarbonyl group, alkyne, cycloalkyne, azide, hydroxylamine group, or masked or protected forms thereof
  • the resulting post-translationally modified drug-linker will contain at least one oxime group; the resulting modified oxime-containing drug-linker may undergo subsequent modification reactions.
  • the polypeptide or non-natural amino acid linked composition includes at least one co-translational or post-translational modification that is made in vivo by one host cell, where the post-translational modification is not normally made by another host cell type.
  • the polypeptide includes at least one co-translational or post-translational modification that is made in vivo by a eukaryotic cell, where the co-translational or post-translational modification is not normally made by a non-eukaryotic cell.
  • co-translational or post-translational modifications include, but are not limited to, glycosylation, acetylation, acylation, lipid-modification, palmitoylation, palmitate addition, phosphorylation, glycolipid-linkage modification, and the like.
  • the co-translational or post-translational modification comprises attachment of an oligosaccharide to an asparagine by a GlcNAc-asparagine linkage (including but not limited to, where the oligosaccharide comprises (GlcNAc-Man) 2 -Man-GlcNAc- GlcNAc, and the like).
  • the co-translational or post-translational modification comprises attachment of an oligosaccharide (including but not limited to, Gal-GalNAc, Gal-GlcNAc, etc.) to a serine or threonine by a GalNAc-serine, a GalNAc-threonine, a GlcNAc-serine, or a GlcNAc-threonine linkage.
  • a protein or polypeptide can comprise a secretion or localization sequence, an epitope tag, a FLAG tag, a polyhistidine tag, a GST fusion, and/or the like.
  • the glycosylated non-natural amino acid polypeptide is produced in a non-glycosylated form.
  • a non-glycosylated form of a glycosylated non-natural amino acid may be produced by methods that include chemical or enzymatic removal of oligosaccharide groups from an isolated or substantially purified or unpurified glycosylated non- WSGR Ref.
  • a host including, prokaryotes or eukaryotes engineered or mutated to not glycosylate such a polypeptide
  • non-glycosylated forms of normally-glycosylated non-natural amino acid polypeptides by normally-glycosylated is meant a polypeptide that would be glycosylated when produced under conditions in which naturally- occurring polypeptides are glycosylated).
  • non-glycosylated forms of normally- glycosylated non-natural amino acid polypeptides may be in an unpurified form, a substantially purified form, or in an isolated form.
  • incorporation of a non-natural amino acid into the antibody or antibody fragment will be combined with other additions, substitutions, or deletions within the polypeptide to affect other chemical, physical, pharmacologic and/or biological traits.
  • the other additions, substitutions or deletions may increase the stability (including but not limited to, resistance to proteolytic degradation) of the polypeptide or increase affinity of the polypeptide for its appropriate receptor, ligand and/or binding proteins.
  • the other additions, substitutions or deletions may increase the solubility (including but not limited to, when expressed in E. coli or other host cells) of the polypeptide.
  • sites are selected for substitution with a naturally encoded or non-natural amino acid in addition to another site for incorporation of a non- natural amino acid for the purpose of increasing the polypeptide solubility following expression in E. coli, or other recombinant host cells.
  • the polypeptides comprise another addition, substitution, or deletion that modulates affinity for the associated ligand, binding proteins, and/or receptor, modulates (including but not limited to, increases or decreases) receptor dimerization, stabilizes receptor dimers, modulates circulating half-life, modulates release or bio-availability, facilitates purification, or improves or alters a particular route of administration.
  • non- natural amino acid polypeptide can comprise chemical or enzyme cleavage sequences, protease cleavage sequences, reactive groups, antibody-binding domains (including but not limited to, FLAG or poly-His) or other affinity based sequences (including but not limited to, FLAG, poly-His, GST, etc.) or linked molecules (including but not limited to, biotin) that improve detection (including but not limited to, GFP), purification, transport thru tissues or cell membranes, prodrug release or activation, size reduction, or other traits of the polypeptide.
  • ADCs Antibody Drug Conjugates
  • ADCs Antibody drug conjugates of the present disclosure provide novel therapeutics or anti-cancer drugs by combining the selectivity of antibodies comprising one or more non-natural amino acids and a cytotoxic agent. Targeted cytotoxic drug delivery into tumor tissue increases the therapeutic window of these agents considerably.
  • ADCs of the present disclosure comprise of an antibody bound to a cytotoxic drug via a linker. Stability of the linker between the antibody and the cytotoxic drug is essential for the ADC integrity in circulation. The successful ADC development for a given target antigen depends on optimization of antibody selection, linker design and stability, drug potency and mode of drug and linker conjugation to the antibody.
  • the antibody of the ADC comprises a full length antibody or fragment thereof that binds to an antigen, and is conjugated to a cytotoxic agent or an immunosuppressive agent, wherein the antibody-drug conjugate exerts: (a) a cytotoxic or cytostatic effect on the antigen-expressing or antigen targeting cell line, or (b) a cytotoxic, cytostatic, or immunosuppressive/immune activating effect on an antigen-expressing immune cell, wherein the conjugation occurs at a non-natural amino acid in the antibody.
  • the antigen, antigen-expressing cell, or antigen-targeting cell, or antigen-expressing immune cell is PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, C-D123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Fact
  • the antigen, antigen-expressing cell, or antigen-targeting cell, or antigen-expressing immune cell is a TROP2, or HER2 or CD70 antigen, or antigen-targeting cell, or antigen-expressing cell or antigen-expressing immune cell.
  • the antibody of the ADC comprises a full length antibody or fragment thereof that: binds to TROP2 and is conjugated to a cytotoxic agent or an immunosuppressive agent, wherein the antibody-drug conjugate exerts: (a) a cytotoxic or cytostatic effect on a TROP2-expressing cancer cell line, or (b) a cytotoxic, cytostatic, or immunosuppressive/immune activating effect on a TROP2-expressing immune cell, wherein the conjugation occurs at a non-natural amino acid in the antibody.
  • the antibody, variant, or composition of the present disclosure may be an antibody, variant, or composition that binds to an antigen receptor.
  • the antibody, variant, or composition may be an antibody, variant, or composition that binds to extracellular surface of an antigen receptor.
  • the antibody, variant, or composition of the present disclosure may be an antibody, variant, or composition that has CDRs grafted onto the framework region of the variable region.
  • the antibody, variant, or composition of the present disclosure may be an antibody, variant, or composition that has a non- natural amino acid.
  • the antibody, variant, or composition may be an antibody, variant, or composition that is described by more than one of the embodiments elsewhere herein the present disclosure.
  • the antibody, antibody variant or antibody composition(s) disclosed herein may be fully humanized.
  • the antibody, antibody variant or antibody composition(s) disclosed herein may be chimeric.
  • the antibody may be an antibody that is full length antibody (Variable + Fc regions), Fab, bispecific, Fab-dimers, Fab- bispecific, Fab-trispecific, bispecific T-cell engagers, dual-affinity re-targeting antibody, IgG1/IgG3 bispecific antibody, diabody, bispecific diabody, scFv-Fc, minibody.
  • the ADC comprises an antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the antibody.
  • the antibody comprises at least one non-natural amino acid; non-limiting examples of non-natural amino acids are disclosed herein.
  • the ADC comprises an antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the heavy chain of the antibody. In some embodiments, the ADC comprises an antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the light chain of the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein the conjugation occurs via a non- natural amino acid in the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the heavy chain of the antibody.
  • the ADC comprises a full-length antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the light chain of the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein a first conjugation occurs via a non-natural amino acid in the heavy chain of the antibody, and a second conjugation occurs via a non-natural amino acid in the light chain of the antibody. In some embodiments, the full-length antibody comprises two full-length heavy chains and two full-length light chains, wherein a first pair of conjugations occur via a non-natural amino acid in each heavy chain of the antibody, and a second pair of conjugations occur via a non-natural amino acid in each light chain of the antibody.
  • the drug of the ADC is a cytotoxic drug or agent.
  • the cytotoxic drug is exatecan, an exatecan derivative or exatecan analog.
  • the drug is a drug generated as described in the Examples herein.
  • the ADC comprises an antibody, antibody fragment or variant thereof engineered to have one or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker.
  • an ADC of the present disclosure an ADC of Formula (V) or (VI): wherein: Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids; L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –, -O-, -C(O)- and -N(R w )-, , wherein each nn is independently an integer from 1 to 100; wherein each R w is independently H or C 1 -C 8 alkyl; and combinations thereof. In some embodiments, each Rw is independently H or methyl.
  • E comprises an amide, an ester, a thioester, a pyrrolidine-2,5-dione, an oxime, a 4,5-dihydro-1,2,3-triazole or a 1,4-dihydropyridazine, wherein the 4,5-dihydro-1,2,3- triazole and the 1,4-dihydropyridazine are each optionally fused to an 8-membered ring.
  • E is selected from the group consisting of: WSGR Ref.
  • each R b is independently H or unsubstituted alkyl; each Rc is unsubstituted alkyl; each Rf is independently H or unsubstituted alkyl, each s is independently 0, 1, 2, 3, 4, 5 or 6, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to L; and each wavy line denotes connection to Ab.
  • each Rb is independently H or unsubstituted C1-C6 alkyl
  • each Rc is unsubstituted C1-C6 alkyl
  • each Rf is independently H or unsubstituted C1-C6 alkyl.
  • E is: wherein + denotes connection to L; the wavy line denotes connection to Ab; and Rc is unsubstituted C 1 -C 6 alkyl. In some embodiments, R c is methyl. In some embodiments, L consists of: WSGR Ref.
  • a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –,-O-, -C(O)-, -N(R w )- and an amino acid; , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl.
  • L is a linker selected from the group of linkers listed in Table 6.
  • each U, in the linkers listed in Table 6, is independently: .
  • each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–.
  • each n is independently 1, 2 or 3.
  • i is 1.
  • i is 0.
  • L is a linker selected from the group of linkers listed in Table 7.
  • each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–.
  • each n is independently 1, 2 or 3.
  • i is 1. In other embodiments, i is 0.
  • L is a linker selected from the group of linkers listed in Table 8. In some embodiments, wherein L is selected from the group of linkers listed in Table 8, each alkylene is independently –(CH 2 )–, –(CH 2 ) 2 – or –(CH 2 ) 3 –. In some embodiments, each n is independently 1, 2 or 3. In some embodiments, i is 1. In other embodiments, i is 0. In some embodiments, L is selected from the group consisting of: WSGR Ref.
  • each m when present, is independently 1, 2 or 3.
  • each n is independently 1, 2 or 3.
  • each q, when present, is independently 1, 2 or 3.
  • each i is 1.
  • d is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, d is 1, 2, 3 or 4.
  • d is 2. In some embodiments, d is 3. In some embodiments, d is 4. In some embodiments, L is: WSGR Ref. No: 31362-826.601 wherein i is 1, n is an integer from 1 to 10, and q is 1. In some further embodiments, n is 1, 2 or 3.
  • the ADC of Formula (V) is an ADC of Formula (Va): ; wherein n is an integer from 1 to 10, and d is an integer from 1 to 10. In some embodiments, d is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, d is 1, 2, 3 or 4. In some embodiments, d is 2. In some embodiments, d is 3. In some embodiments, d is 4.
  • n is 1, 2 or 3. In some further embodiments, n is 2. In yet some further embodiments, E is: ; wherein + denotes connection to (CH 2 ) n ; the wavy line denotes connection to Ab; and R c is unsubstituted C 1 -C 6 alkyl. In some embodiments, R c is methyl. In some other embodiments, L is: ; wherein i is 1, m is an integer from 1 to 10, n is an integer from 1 to 10, and q is 1. In some further embodiments, m is 1, 2 or 3 and n is 1, 2 or 3. Thus, in some embodiments, the ADC of Formula (V) is an ADC of Formula (Vb): WSGR Ref.
  • n is an integer from 1 to 10
  • d is an integer from 1 to 10.
  • d is 1, 2, 3, 4, 5, 6, 7 or 8.
  • d is 1, 2, 3 or 4.
  • d is 2.
  • d is 3.
  • d is 4.
  • m is 1, 2 or 3, and n is 1, 2 or 3.
  • E is: ; wherein + denotes connection to (CH2CH2O)m; the wavy line denotes connection to Ab; and R c is unsubstituted C 1 -C 6 alkyl. In some embodiments, R c is methyl.
  • an ADC of the present invention is represented by the Formula (I): wherein: Drug has the following structure: each n is independently 1 or 2; p is 1, 2, 3, 4, 5, 6, 7 or 8; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; WSGR Ref.
  • each L1 is independently absent, * (CH 2 ) m , * CH 2 -O-(CH 2 ) m , * (CH 2 ) m -O-CH 2 , * C(O)-(CH 2 ) m , * NH-(CH 2 ) m , * (CH 2 ) m (OCH 2 CH 2 ) k , * NH-(CH 2 ) m (OCH 2 CH 2 ) k , C 3 -C 6 cyclic alkylene, * (OCH 2 CH 2 ) m , unsubstituted C 1 -C 6 alkylene or C 1 -C 6 alkylene substituted with 1- 3 groups independently selected from the group consisting of C 1 -C 3 alkyl, hydroxy, NH 2 and C 1 -C 3 alkoxy; wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5
  • each Linker is independently absent, (CH 2 ) v [**], CH 2 -O-(CH 2 ) v [**], (CH 2 ) v -O- CH 2 [**], (CH 2 ) v -C(O) [**], O-(CH 2 ) v [**], O-CH 2 [**], O-(CH 2 ) v -O-C(O) [**], O-CH 2 - O-C(O) [**], NH-(CH 2 ) v [**], (CH 2 ) v (OCH 2 CH 2 )
  • p is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, p is 1, 2, 3 or 4. In some embodiments, p is 2. In some embodiments, p is 3. In some embodiments, p is 4. In some embodiments, n is 1. In some other embodiments, n is 2. In other embodiments, the antibody comprising, containing or incorporating one or more non- natural amino acid is conjugated to the terminal of L3 via a covalent bond. In other embodiments, the antibody comprising, containing or incorporating one or more non-natural amino acid is conjugated to the terminal arm of L3 via an oxime bond. In some embodiments, Drug of Formula (I) has the following structure: . WSGR Ref.
  • an ADC of the present disclosure such as an ADC of Formula (I), Formula (V) or Formula (VI), or a subgenus (e.g., Formula (Va) or (Vb)) or species thereof, are provided below.
  • Ab is configured to bind to an antigen.
  • Ab is configured to bind to a tumor-associated antigen (TAA) or cancer antigen.
  • TAA tumor-associated antigen
  • Ab binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7- H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA
  • TAA
  • Ab binds to an antigen selected from the group consisting of TROP2, CD70, HER2, HER3 and PSMA.
  • the one or more non-natural amino acids is selected from the group consisting of para-acetyl phenylalanine, 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine asparagine, O-allyl-L-tyrosine, alpha-N-acetylgalactosamine-O-L-serine, alpha-N- acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L- phenylalanine, 4-amino-L-phenylalanine, 2-amino-L-tyrosine, 3-amino-L-tyrosine, 4-azido-L- phenylalanine,
  • At least one of the one or more non-natural amino acids is para-acetyl phenylalanine. In some more particular embodiments, at least one of the one or more non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)). In some embodiments, each of the one or more non-natural amino acids is the same. In some embodiments, each of the one or more non-natural amino acids is para-acetyl phenylalanine. In some more particular embodiments, each of the one or more non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)).
  • Ab comprises a heavy chain having a heavy chain amino acid sequence, a light chain having a light chain amino acid sequence, or both.
  • the heavy chain comprises at least one of the one or more non-natural amino acids.
  • the light chain comprises at least one of the one or more non- natural amino acids. In some other embodiments, the light chain does not contain a non-natural amino acid.
  • Ab comprises two heavy chains, wherein each heavy chain comprises at least one of the one or more non-natural amino acids. In some embodiments, Ab comprises two light chains. In some embodiments, each light chain comprises at least one of the one or more non- natural amino acids. In some other embodiments, each light chain does not contain a non-natural amino acid.
  • Ab comprises two heavy chains and two light chains, wherein each heavy chain comprises one non-natural amino acid. In some embodiments, each light chain comprises one non-natural amino acid. In some other embodiments, the light chain does not contain a non- natural amino acid. In some embodiments, Ab comprises 1, 2, 3 or 4 non-natural amino acids. In some embodiments, Ab is an anti-trophoblast antigen 2 antibody (anti-TROP2 Ab), antibody fragment or variant thereof. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 1 to 17.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain amino acid sequence is selected from the group consisting of SEQ ID NOs: 5 and 6.
  • the heavy chain has the amino WSGR Ref. No: 31362-826.601 acid sequence of SEQ ID NO: 5, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17.
  • the light chain has the amino acid sequence of SEQ ID NO: 11, wherein one non-natural amino acid occupies position 121.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 4.
  • the anti-TROP2 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11.
  • Ab is an anti-TROP2 monoclonal antibody comprising two heavy chains and two light chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5, and each light chain has the amino acid sequence of SEQ ID NO: 11.
  • each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime.
  • the ADC is an ADC of Formula (V).
  • the ADC is an ADC of Formula (Va).
  • Ab is an anti-CD70 antibody (anti-CD70 Ab), antibody fragment or variant thereof.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 18 to 24.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 20, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 19.
  • the light chain has the amino acid sequence of SEQ ID NO: 24, wherein one non- natural amino acid occupies position 121.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 20.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 19.
  • the anti-CD70 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 24.
  • each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and WSGR Ref. No: 31362-826.601 each E comprises an oxime.
  • the ADC is an ADC of Formula (V).
  • the ADC is an ADC of Formula (Va).
  • Ab is an anti-HER2 antibody (anti-HER2 Ab), antibody fragment or variant thereof.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 25 to 28.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 26, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti- HER2 Ab, antibody fragment or variant thereof comprises a light chain.
  • the light chain has the amino acid sequence of SEQ ID NO: 27.
  • the light chain has the amino acid sequence of SEQ ID NO: 28, wherein one non-natural amino acid occupies position 121.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 26.
  • the anti-HER2 Ab, antibody fragment or variant thereof comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 27. In some other embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 28. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime.
  • the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va). In some other embodiments, Ab is an anti-PSMA antibody (anti-PSMA Ab), antibody fragment or variant thereof.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 29 to 45.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 36, 38, 40, 42 and 44, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 37, 39, 41, 43 and 45.
  • the anti-PSMA Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 36. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises two light chains. In some embodiments, each light chain has the amino acid sequence of SEQ ID NO: 37. In some embodiments, each non-natural amino acid is para-acetyl- WSGR Ref. No: 31362-826.601 L-phenylalanine (pAF), and each E comprises an oxime.
  • the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va).
  • Ab is an anti-HER3 antibody (anti-HER3 Ab), antibody fragment or variant thereof.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 46 to 58.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 58, wherein one non-natural amino acid occupies Kabat position 114.
  • the anti- HER3 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 47 to 57.
  • the light chain has the amino acid sequence of SEQ ID NO: 47. In some other embodiments, the light chain has the amino acid sequence of SEQ ID NO: 51, wherein one non- natural amino acid occupies position 121.
  • the anti-HER3 Ab, antibody fragment or variant thereof comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 47. In some other embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51.
  • Ab is an anti-HER3 monoclonal antibody comprising two heavy chains and two light chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58, and each light chain has the amino acid sequence of SEQ ID NO: 51.
  • each non- natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime.
  • the ADC is an ADC of Formula (V).
  • the ADC is an ADC of Formula (Va). It is understood that an ADC is typically produced as a composition containing a population of ADCs, i.e., a mixture of ADCs that are essentially identical, except for the drug load.
  • an ADC composition can be characterized by a drug-to-antibody ratio (DAR), which reports on the average number of drugs conjugated to antibody in the ADC composition.
  • DAR drug-to-antibody ratio
  • an ADC of the present disclosure has a drug to antibody ratio of about 1, about 2, about 3 or about 4, about 5, about 6, about 7 or about 8.
  • an ADC of the present disclosure has a drug to antibody ratio of about 1, about 2, about 3 or about 4.
  • an ADC of the present disclosure has a drug to antibody ratio of about 1.
  • an ADC of the present disclosure has a drug to antibody ratio of about 2. In some other WSGR Ref.
  • an ADC of the present disclosure has a drug to antibody ratio of about 3. In some other embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 4. In some aspects, the present disclosure provides an ADC composition comprising a mixture of ADCs, wherein each ADC in the mixture is identical, except that the number of drugs or drug- linkers that are conjugated to each ADC can vary.
  • an ADC of the present disclosure comprises a first ADC, a second ADC, a third ADC and a fourth ADC, wherein the first ADC, the second ADC, the third ADC and the fourth ADC are identical, except that the first ADC comprises one drug or drug-linker, the second ADC comprises two drugs or drug-linkers, the third ADC comprises three drugs or drug-linkers, and the fourth ADC comprises four drugs or drug-linkers.
  • an ADC composition comprising: (a) an ADC of Formula (I), wherein p is 1; (b) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 2; (c) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 3; (d) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 4; (e) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 5; (f) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 6; (g) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 7; or (h) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 8; or a combination of any two or more of the foregoing; wherein
  • the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, or at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4.
  • an ADC composition comprising: (a) an ADC of Formula (I), wherein p is 1; (b) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 2; (c) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 3; (d) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 4.
  • an ADC composition comprising: (a) an ADC of Formula (V), wherein d is 1; (b) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 3; (d) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 4; (e) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 5; (f) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 6; (g) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 7; (h)
  • the ADC composition is characterized as having a DAR of at least about 1 and at most about 8. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, or at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4.
  • an ADC composition comprising: (a) an ADC of Formula (V), wherein d is 1; (b) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 3; or (d) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 4.
  • the ADC composition is characterized as having a DAR of at least about 3 and at most about 4.
  • an ADC composition comprising: (a) an ADC of Formula (VI), wherein d is 1; (b) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 3; (d) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 4; (e) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 5; WSGR Ref.
  • the ADC composition is characterized as having a DAR of at least about 1 and at most about 8. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, or at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4.
  • an ADC composition comprising: (a) an ADC of Formula (VI), wherein d is 1; (b) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 3; or (d) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 4.
  • the ADC composition is characterized as having a DAR of at least about 3 and at most about 4.
  • an ADC or composition of the present disclosure excludes a Toll-like receptor (TLR) agonist.
  • TLR Toll-like receptor
  • an antibody, antibody fragment, variant or drug conjugate with increased serum half-life, water solubility, bioavailability, therapeutic half-life or circulation time, or with modulated immunogenicity, or with modulated biological activity is desired.
  • One method of achieving such desired features of the compositions disclosed herein, is by covalent attachment of the polymer polyethylene glycol, (PEG).
  • the total molecular weight and hydration state of the polymer or polymers attached to the biologically active molecule must be sufficiently high to impart the advantageous characteristics typically associated with such polymer attachment, such as increased water solubility and circulating half-life, while not adversely impacting the bioactivity of the molecule to which the PEG is attached.
  • PEG derivatives are frequently linked to biologically active molecules through reactive chemical WSGR Ref. No: 31362-826.601 functionalities, such as amino acid residues, the N-terminus, and/or carbohydrate moieties.
  • PEG derivatives are linked to biologically active molecules through reactive chemical functionalities to improve biophysical properties of the resulting ADC.
  • WO99/67291 discloses a process for conjugating a protein with PEG, wherein at least one amino acid residue on the protein is substituted with a synthetic amino acid and the protein is contacted with PEG under conditions sufficient to achieve conjugation to the protein.
  • antibody, antibody fragments, variant or drug conjugate with increase serum half-life, water solubility, bioavailability, therapeutic half-life, or circulation time, or to modulate immunogenicity, or biological activity is desired.
  • One method of achieving such desired features of the composition disclosed herein, is by covalent attachment of the polymer polyethylene glycol, (PEG).
  • the total molecular weight and hydration state of the polymer or polymers attached to the biologically active molecule must be sufficiently high to impart the advantageous characteristics typically associated with such polymer attachment, such as increased water solubility and circulating half-life, while not adversely impacting the bioactivity of the molecule to which the PEG is attached.
  • PEG derivatives are frequently linked to biologically active molecules through reactive chemical functionalities, such as amino acid residues, the N-terminus, and/or carbohydrate moieties.
  • PEG derivatives are linked to biologically active molecules through reactive chemical functionalities to improve biophysical properties of the resulting ADC.
  • WO99/67291 discloses a process for conjugating a protein with PEG, wherein at least one amino acid residue on the protein is substituted with a synthetic amino acid and the protein is contacted with PEG under conditions sufficient to achieve conjugation to the protein.
  • Proteins and other molecules often have a limited number of reactive sites available for polymer attachment. The sites most suitable for modification via polymer attachment may play a significant role in receptor binding, and such sites may be necessary for retention of the biological activity of the molecule therefore making them inappropriate for polymer attachment.
  • PEG attachment can be directed to a particular position within a protein such that the PEG moiety does not interfere with the function of that protein.
  • One method of directing PEG attachment is to introduce a synthetic amino acid into the protein sequence.
  • the protein biosynthetic machinery of the prokaryote Escherichia coli (E. coli) can be altered in order to incorporate synthetic amino acids efficiently and with high fidelity into proteins in response to the amber codon, UAG. See, e.g., J. W. Chin et al., J. Amer. Chem.
  • a non-natural amino acid can be incorporated into an antibody, variant or drug conjugate of the present disclosure, providing an attachment site for PEG. See, for example WO2010/011735 and WO2005/074650.
  • Methodology and Techniques The present disclosure encompasses methodologies and technologies well known in the art. These include conventional methods of mass spectroscopy, NMR, HPLC, protein chemistry, biochemistry, recombinant DNA techniques and pharmacology, within the skill of the art. Compounds of the present disclosure can be synthesized using several processes or schemes employed in the art.
  • ADCs Therapeutic Uses of ADCs
  • the antibodies or ADCs of the disclosure are useful for treating a wide range of diseases. disorders, conditions, or cancers.
  • compositions disclosed herein may be used to modulate an immune response.
  • Modulation of an immune response may comprise stimulating, activating, increasing, enhancing, or up-regulating an immune response.
  • Modulation of an immune response may comprise suppressing, inhibiting, preventing, reducing, or downregulating an immune response.
  • the ADCs of the present invention may be used for reducing or inhibiting tumor growth or progression in an antigen-expressing cancer or cancer cell comprising an effective amount of the ADC.
  • methods of treating a subject for a condition with an ADC or pharmaceutical composition of the disclosure can allow selective targeting of cancerous cells with small molecules or drugs, while minimizing effects on healthy cells.
  • the invention provides a method of treating cancer by administering to a patient a therapeutically-effective amount of an ADC of the invention comprising an antibody or antibody fragment conjugated to a drug-linker disclosed herein.
  • the cancer to be treated by an ADC of the present invention may be, a breast cancer including triple negative breast cancer (TNBC), a brain cancer, a pancreatic cancer, a skin cancer, a lung cancer, a liver cancer, a gall bladder cancer, a colon cancer, an ovarian cancer, a prostate cancer, a uterine cancer, a bone cancer, and a blood cancer (leukemic) cancer or a cancer or disease or conditions related to any of these cancers.
  • TNBC triple negative breast cancer
  • the invention provides a method of treating cancer by administering to a patient a therapeutically-effective amount of an ADC of the invention.
  • the cancer may be an antigen expressing cancer.
  • the cancer may be ovarian cancer including, but not limited to, an epithelial, stromal and germ cell tumor.
  • the ovarian cancer may comprise a fallopian tube cancer or primary peritoneal carcinoma.
  • the cancer may be characterized by high expression of an antigen receptor.
  • the cancer may be treated by recruiting cytotoxic T cells to the antigen receptor expressing tumor cells.
  • the disclosure provides a method of treating any cancer, disease or condition associated with high expression of antigen receptors by administering to a patient a WSGR Ref.
  • the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an antibody or ADC of the invention.
  • the antibody, antibody fragment or variant thereof binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, C-D123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue
  • TAA
  • the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-TROP2 antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-HER2 antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-HER3 antibody or ADC of the invention.
  • the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-PSMA antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-CD70 antibody or ADC of the invention. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high TROP2 receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high HER2 receptor number.
  • the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high HER3 receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high PSMA receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high CD70 receptor number.
  • the antibodies and ADCs of the disclosure are for use in treating cancer including, but not WSGR Ref. No: 31362-826.601 limited to, ovarian cancer ovarian cancer including, but not limited to, an epithelial, stromal and germ cell tumor.
  • the ovarian cancer may comprise a fallopian tube cancer or primary peritoneal carcinoma.
  • the cancer may be characterized by high expression of antigen receptors, such as ovarian cancer, for example.
  • the cancer may be treated by recruiting cytotoxic T cells to high expressing antigen receptor tumor cells.
  • the antibodies of the disclosure are for use in treating inherited diseases, AIDS, or diabetes but is not limited to such.
  • the antibodies, compounds or composition or conjugates of the disclosure can be used in the manufacture of a medicament for treating a disease or condition in a cell expressing high receptor number.
  • the antibodies, compounds or composition or conjugates of the disclosure can be used in the manufacture of a medicament for treating cancer including, but not limited to, breast cancer including triple negative breast cancer, ovarian cancer including, but not limited to, an epithelial, stromal and germ cell tumor.
  • the antibodies of the invention can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with expression of an antigen receptor such as TROP2, or HER2, or HER3, or PSMA, or CD70, antigen receptor for example.
  • the anti-TROP2 antibodies of the invention can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with high TROP2 receptor numbers.
  • the anti-HER2 antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with HER2 expression.
  • the anti-HER3 antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with HER3 expression.
  • the anti-PSMA antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with PSMA expression.
  • the anti-CD70 antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with CD70 expression.
  • the condition to be treated is a cancer.
  • the cancer may be, but is non- limited to, a breast cancer including triple negative breast cancer (TNBC), a brain cancer, a pancreatic cancer, a skin cancer, a lung cancer, a liver cancer, a gall bladder cancer, a colon cancer, an ovarian cancer, a prostate cancer, a uterine cancer, a bone cancer, and a blood cancer (leukemic) cancer or a cancer or disease or conditions related to any of these cancers.
  • TNBC triple negative breast cancer
  • Carcinomas are cancers that begin in the epithelial cells, which are cells that cover the surface of the body, produce hormones, and make up glands.
  • carcinomas include breast cancer, pancreatic cancer, lung cancer, colon cancer, colorectal cancer, rectal cancer, kidney cancer, bladder cancer, stomach cancer, prostate cancer, liver cancer, ovarian cancer, brain cancer, vaginal cancer, vulvar cancer, uterine cancer, oral cancer, penile cancer, testicular cancer, esophageal cancer, skin cancer, cancer WSGR Ref.
  • CNS central nervous system
  • the cancer is a skin cancer, such as a basal cell carcinoma, squamous, melanoma, nonmelanoma, or actinic (solar) keratosis.
  • the cancer is any cancer with highly expressed antigen receptor numbers such as, for example, TROP2 antigen receptor numbers, HER2 antigen receptor numbers, HER3 antigen receptor numbers, PSMA antigen receptor numbers or CD70 antigen receptor numbers.
  • the condition to be treated is a disease or condition associated with or having a high antigen receptor number such as, for example, TROP2 antigen receptor number, HER2 antigen receptor number, HER3 antigen receptor number, PSMA antigen receptor numbers or CD70 antigen receptor number.
  • the disease or condition may be a pathogenic infection.
  • the pathogenic infection may be a bacterial infection.
  • the pathogenic infection may be a viral infection.
  • the disease or condition may be an inflammatory disease.
  • the disease or condition may be an autoimmune disease.
  • the autoimmune disease may be diabetes.
  • the disease or condition may be a cancer.
  • the disease or condition is any disease or condition with highly expressed antigen receptor numbers such as, for example, TROP2 antigen receptor numbers.
  • the disease or condition may be a pathogenic infection.
  • the biologically active molecule may interact with a cell surface molecule on an infected cell.
  • the biologically active molecule may interact with a molecule on a bacterium, a virus, or a parasite.
  • Pathogenic infections may be caused by one or more pathogens.
  • the pathogen is a bacterium, fungi, virus, or protozoan.
  • exemplary pathogens include but are not limited to: Bordetella, Borrelia, Brucella, Campylobacter, Chlamydia, Chlamydophila, Clostridium, Corynebacterium, Enterococcus, Escherichia, Francisella, Haemophilus, Helicobacter, Legionella, Leptospira, Listeria, Mycobacterium, Mycoplasma, Neisseria, Pseudomonas, Rickettsia, Salmonella, Shigella, Staphylococcus, Streptococcus, Treponema, Vibrio, or Yersinia.
  • the pathogen may be a virus.
  • viruses include, but are not limited to, adenovirus, coxsackievirus, Epstein-Barr virus, Hepatitis virus (e.g., Hepatitis A, B, and C), herpes simplex virus (type 1 and 2), cytomegalovirus, herpes virus, HIV, influenza virus, measles virus, mumps virus, papillomavirus, parainfluenza virus, poliovirus, respiratory syncytial virus, rubella virus, and varicella-zoster virus.
  • diseases or conditions caused by viruses include, but are not limited to, cold, flu, hepatitis, AIDS, chicken pox, rubella, mumps, measles, warts, and poliomyelitis.
  • the disease or condition may be an autoimmune disease or autoimmune WSGR Ref. No: 31362-826.601 related disease.
  • An autoimmune disorder may be a malfunction of the body's immune system that causes the body to attack its own tissues.
  • autoimmune diseases and autoimmune related diseases include, but are not limited to, Addison's disease, alopecia areata, ankylosing spondylitis, antiphospholipid syndrome (APS), autoimmune aplastic anemia, autoimmune hemolytic anemia, autoimmune hepatitis, autoimmune myocarditis, Behcet’s disease, celiac sprue, Crohn’s disease, dermatomyositis, eosinophilic fasciitis, erythema nodosum, giant cell arteritis (temporal arteritis), Goodpasture’s syndrome, Graves' disease, Hashimoto’s disease, idiopathic thrombocytopenic purpura (ITP), IgA nephropathy, juvenile arthritis, diabetes, juvenile diabetes, Kawasaki syndrome, Lambert-Eaton syndrome, lupus (SLE), mixed connective tissue disease (MCTD), multiple sclerosis, myasthenia gravis, pemphigus, polyarteritis
  • the disease or condition may be an inflammatory disease.
  • inflammatory diseases include, but are not limited to, alveolitis, amyloidosis, angiitis, ankylosing spondylitis, avascular necrosis, Basedow's disease, Bell's palsy, bursitis, carpal tunnel syndrome, celiac disease, cholangitis, chondromalacia patella, chronic active hepatitis, chronic fatigue syndrome, Cogan's syndrome, congenital hip dysplasia, costochondritis, Crohn's Disease, cystic fibrosis, De Quervain’s tendinitis, diabetes associated arthritis, diffuse idiopathic skeletal hyperostosis, discoid lupus, Ehlers-Danlos syndrome, familial mediterranean fever, fascitis, fibrositis/fibromyalgia, frozen shoulder, ganglion cysts, giant cell arteritis, gout, Graves' Disease, HIV-
  • compositions containing an antibody or ADC of the invention may be formulated at a strength effective for administration by various means to a human patient experiencing disorders that may be affected by antibody agonists or antagonists, such as but not limited to, anti-proliferatives, anti-inflammatory, or anti-virals are used, either alone or as part of a condition or disease.
  • Average quantities of an antibody or ADC may vary and in particular should be based upon the recommendations and prescription of a qualified physician.
  • the exact amount of an antibody or ADC is a matter of preference subject to such factors as the exact type of condition being treated, the condition of the patient being treated, as well as the other ingredients in the composition.
  • the disclosure also provides for administration of a therapeutically effective amount of another active agent such as an anti-cancer chemotherapeutic agent or immunotherapeutic agent but is not limited to such.
  • another active agent such as an anti-cancer chemotherapeutic agent or immunotherapeutic agent but is not limited to such.
  • the amount to be given may be readily determined by one skilled in the art based upon therapy with the antibody or ADCs of the invention.
  • Pharmaceutical Compositions In other aspects of the present invention the antibody, antibody fragments, variants or ADCs further comprise a pharmaceutical composition or formulation.
  • Such a pharmaceutical composition can employ various pharmaceutically acceptable excipients, stabilizers, buffers, and other components for administration to animals. See, for example, Remington, The Science and Practice of Pharmacy, 19th ed., Gennaro, ed., Mack Publishing Co., Easton, PA, 1995.
  • Suitable composition or formulations for stability, administration to a subject, and activity varies with each compound as a number of components, (for example, purifying, stabilizing components), need to be considered.
  • Suitable salts for inclusion into the composition or formulation can include, but not limited to, sodium chloride, potassium chloride or calcium chloride. Buffering and/or stabilizing agents such as sodium acetate can be used.
  • Suitable buffers can include phosphate-citrate buffer, phosphate buffer, citrate buffer, L-histidine, L-arginine hydrochloride, bicarbonate buffer, succinate buffer, citrate buffer, and TRIS buffer, either alone or in combination.
  • the pharmaceutical composition or formulation can be an aqueous composition or in the form of a reconstituted liquid composition or as a powder.
  • the composition or formulation can have a pH range from about 4.0 to about 7.0 or from about 4.5 to about 6.5 when the formulation is in a liquid form.
  • the pH can be adjusted to provide acceptable stability and administration by the skilled medical practitioner.
  • the composition can be stored in a vial or cartridge, a pen delivery device, a syringe, intravenous administration tubing or an intravenous administration bag but is not limited to such.
  • a pharmaceutical composition of the invention can be administered as a single dose or followed by one or more subsequent dose(s) minutes, days, or weeks after the first dose. Further administrations may be contemplated as needed to treat, reduce or prevent a cancer, condition, disorder or disease.
  • the antibodies, antibody fragments, variants, or ADCs of the present invention disclosure may be used in conjunction with an additional therapy or treatment including but not limited to surgery, radiation, cryosurgery, thermotherapy, hormone treatment, chemotherapy, vaccines and other immunotherapies.
  • such additional treatment can include a therapeutic agent such as chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid or combination thereof.
  • a therapeutic agent such as chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid or combination thereof.
  • the antibodies, antibody fragments, variants, or ADCs of the invention can be administered with one or more immunostimulatory agents to induce or enhance an immune response.
  • Immunostimulatory agents that can stimulate specific arms of the immune system, such as natural killer (NK) cells that mediate antibody-dependent cell cytotoxicity (ADCC).
  • immunostimulatory agents include, but are not limited to, IL-2, immunostimulatory oligonucleotides embodiments the ADCs of the invention can be administered with one or more immunomodulators including, but not limited to, cytokines, chemokines (including, but are not limited to, SLC5 ELC, that immunizes a subject against an antigen such as, for example, TROP2, HER2, HER3, PSMA or CD70.
  • immunomodulators including, but not limited to, cytokines, chemokines (including, but are not limited to, SLC5 ELC, that immunizes a subject against an antigen such as, for example, TROP2, HER2, HER3, PSMA or CD70.
  • Such vaccines include antigens, with, optionally, one or more adjuvants to induce or enhance an immune response.
  • adjuvants of many kinds are well known in the art.
  • chemotherapeutic agents may include, but are not limited to, erlotinib (TARCEVA®, Genentech/OSI Pharm.), bortezomib (VELCADE®, Millennium Pharm.), fulvestrant (FASLODEX®, AstraZeneca), sutent (SU11248, Pfizer), letrozole (FEMARA®, Novartis), imatinib mesylate (GLEEVEC®, Novartis), PTK787/ZK 222584 (Novartis), oxaliplatin (Eloxatin®, Sanofi), 5-FU (5-fluorouracil), leucovorin, Rapamycin (Sirolimus, RAPAMUNE®, Wyeth), lapatinib (TYKERB®, GSK572016, Glax
  • aziridines such as benzodopa, carboquone, meturedopa, and uredopa; ethylenimines and methylamelamines including altretamine, triethylenemelamine, triethylenephosphoramide, triethylenethiophosphoramide and trimethylomelamine; acetogenins (especially bullatacin and bullatacinone); a camptothecin (including the synthetic analogue topotecan); bryostatin; callystatin; CC-1065 (including its adozelesin, carzelesin and bizelesin synthetic analogues); cryptophycins (particularly cryptophycin 1 and cryptophycin 8); dolastatin; duocarmycin (including the synthetic analogues, KW-2189 and CB1-TM1); eleutherobin; pancratistatin; a sarcodictyin; spongistatin; nitrogen
  • Example 1 General Experimental Procedures Chemical reagents and solvents were obtained from the following sources unless expressly indicated otherwise: 1 ClickChemistry Inc. (Kendall Park, NJ), AA Blocks LLC (San Diego, CA), ACES PHARMA (Princeton, NJ), AK Scientific, Inc.
  • ACN acetonitrile
  • CDI 1,1'- carbonyldiimidazole
  • DAD diode array detection/detector
  • DBU 1,8-diazabicyclo[5.4.0]undec-7- ene
  • DCM dichloromethane
  • DIEA N,N-diisopropylethylamine
  • DIAD diisopropyl WSGR Ref.
  • Example 2 Synthesis of compound 10 General Procedure for the synthesis of Compound 10 All commercially available anhydrous solvents were used without further purification. DMF was dried over molecular sieve pack 4 ⁇ powder (Bide Pharmatech). TLC was performed on Liang Chen Silica gel GF254 plates using UV light for visualization. Chromatographic purification was performed on Flash Column Silica-CS from Agela Technologies using conditions detailed in the experimental procedure. Preparative HPLC was performed on Gilson 281 system using a Waters Xbridge Prep OBD C1810 ⁇ m 150 ⁇ 40 mm column. NMR spectral data were collected on a 400 deuterium solvent signal. Coupling constants (J) are reported in hertz (Hz).
  • LCMS was performed using an Agilent LCMS-6130 system with Agilent LabSolutions software for data processing, or an Agilent 1200 Infinity Binary LC coupled with 6130 Accurate- Mass MS system for ESI analysis, using analytical methods described below.
  • Analytical Method 1 LCMS was performed using an Agilent Poroshell 2.7 ⁇ m SB-C18, 3.0 ⁇ 30 mm column. Detection methods were DAD and MS with positive electrospray ionization with a range of 50-2000.
  • Mobile phase A was 0.04% TFA in water, and mobile phase B was 0.02% TFA in HPLC grade ACN.
  • the gradient was 5-95% B over 0.70 min, 95% B (0.70-1.16min), 95-5% B (1.16-1.50min).
  • the flow rate was 1.5 mL/min.
  • Analytical Method 2 LCMS was performed using an Agilent Poroshell 2.7 ⁇ m SB-C18, 3.0 ⁇ 30 mm column. Detection methods were DAD and and MS positive electrospray ionization with a range of 50-2000.
  • Mobile phase A was 0.04% TFA in water, and mobile phase B was 0.02% TFA in HPLC grade ACN.
  • Example 3 Synthesis of Compound 16 General Procedure for the synthesis of Compound 16 All commercially available anhydrous solvents were used without further purification and were stored under a nitrogen atmosphere. TLC was performed on Merck Silica gel 60 F254 plates using UV light and/or staining with aqueous KMnO4 solution for visualization. Chromatographic purification was performed on Combi Flash Rf from Teledyne ISCO using conditions detailed in the experimental procedure. Preparative HPLC was performed on Shimadzu system using Gemini-NX C185 ⁇ m 100 x 30 mm, 150 x 30 mm or 250 x 50 mm column, depending on the scale. MS was performed on a Shimadzu LCMS-2020 system and data were processed using Shimadzu LabSolutions software.
  • Agilent 1260 Infinity Binary LC coupled with 6230 Accurate-Mass TOFMS system was used for HR-ESI-TOF analysis.
  • Analytical HPLC was performed on Shimadzu system using either an Agilent Zorbax 1.8 ⁇ m / SR-C182.1 ⁇ 50 mm, or a Waters BEH 1.7 pm v2.1 x 50 mm column, using methods described below.
  • Analytical Method 7 Mobile phase A was 0.05% formic acid in water, and mobile phase B was 0.05% formic acid in 90% ACN aqueous solution.
  • Compound 18 can be synthesized according to the following scheme: WSGR Ref. No: 31362-826.601 [[[3-[(2-Aminooxyacetyl)amino]-5-[[[(10S,23S)-10-ethyl-18-fluoro-10-hydroxy-19-methyl- 5,9-dioxo-8-oxa-4,15-diazahexacyclo[14.7.1.0 2,14 .0 4,13 .0 6,11 .0 20,24 ]tetracosa- 1,6(11),12,14,16,18,20(24)-heptaen-23-yl]carbamoyloxymethoxy-hydroxy-phosphoryl]oxy- hydroxy-phosphoryl]oxy-phenoxy]-hydroxy-phosphoryl]oxy-hydroxy-phosphoryl]oxymethyl N- [(10S,23S)-10-ethyl-18-fluoro-10-hydroxy-19-methyl-5,9-dioxo-8-oxa-4,15- diaza
  • Compound 19 can be synthesized according to the following scheme: WSGR Ref. No: 31362-826.601
  • Example 5 Site Specific Conjugation of Drug-Linkers
  • the synthesized drug-linker compounds generated by the above schemes are utilized in engineering ADCs. Briefly, anti-TROP2, anti-CD70, anti-HER2, anti-PSMA or anti-HER3 antibodies, each containing non-natural amino acid para-acetyl-L-phenylalanine (pAF) on heavy chains at amino acid position 114, are buffer exchanged into 30 mM sodium acetate; 2.5% trehalose, pH 4.0-4.3 and concentrated to 10-20 mg/mL.
  • pAF para-acetyl-L-phenylalanine
  • Acetic hydrazide (100mM) and amino-oxy functionalized drug-linker compounds 10 and 16 (10-25 molar equivalents) are added and reacted for 16-48 hours at 30 °C.
  • the resulting ADCs are purified over a cation exchange column (Capto SP Impres, Cytiva) to remove excess reagents.
  • the purified ADCs are buffer exchanged into until further use.
  • Exemplary ADCs comprising Compounds 10 or 16 are illustrated below.
  • Scheme showing exemplary ADCs engineered by conjugating Compound 10 with anti- TROP2, anti-CD70, anti-HER2, anti-PSMA or anti-HER3 mAb comprising non-natural amino acid pAF Scheme showing exemplary ADCs engineered by conjugating Compound 16 with anti- TROP2, anti-CD70, anti-HER2, anti-PSMA or anti-HER3 mAb comprising non-natural amino acid pAF: WSGR Ref.
  • ADCs containing anti-HER3 antibody conjugated to Compound 10 or 16 were buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide was added to the antibodies followed by 10-25 molar equivalents of compound 10, and, in a separate experiment, compound 16.
  • the conjugation reactions were incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (GE Healthcare) to remove excess reagents.
  • the purified ADCs were of each ADC was recorded at two different wavelengths using a Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compounds 10 and 16 were used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for each conjugate was obtained from the ratio of these values: anti-HER3- HA114/LS121-Compound-10, DAR: 3.56; anti-HER3-HA114/LS121-Compound-16, DAR: 3.11.
  • ADCs containing anti-TROP2 antibody conjugated to Compound 10 (DAR > 3): Anti-TROP2 antibody containing non-natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 5; Table 1) and Kabat position 121 of each light chain (SEQ ID NO: 11; Table 1) were buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide was added to the antibodies followed by 10-25 molar equivalents of compound 10. The conjugation reaction was incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (Cytiva) to remove excess reagents.
  • the purified ADC was buffer exchanged into pH 6.0 histidine buffer and stored at using a Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compound 10 was used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for the conjugate was obtained from the ratio of these values: anti-TROP2-HA114/LS121-Compound-10, DAR: 3.76.
  • the conjugation reaction is incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (Cytiva) to remove excess reagents.
  • the purified ADC is buffer exchanged recorded at two different wavelengths using Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compound 10 or compound 16 are used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for the conjugate is obtained.
  • the resulting plasmids were propagated in E. coli and verified by a DNA sequencing service (Eton Biosciences, San Diego, CA). Generation of amber codon-containing mutants - Based on the crystal structure of anti-HER2 Fab, ten different surface-accessible sites located at light chain constant region were chosen to genetically incorporate non-natural amino acid (e.g., pAF). Those sites are not critical for antigen- antibody binding. Each genetic codon of the chosen site was then mutated to amber codon (TAG) via site-directed mutagenesis to generate expression plasmid for that antibody mutant. Primers were purchased from IDT. All site directed mutagenesis experiments were carried out using Q5 site- directed mutagenesis kit following instruction manuals (NEB).
  • Anti-HER3 antibodies include anti-HER3 antibodies, anti-TROP2 antibodies, anti-CD70 antibodies, anti-HER2 antibodies, and anti-PSMA antibodies each containing pAF.
  • Transient expression - Platform cell line was maintained in EX-CELL 302 (Sigma) supplemented with 3 mM L-glutamine (Gibco) and 3 mM GlutaMAX (Gibco). Cells were passaged every 3 to 4 days seeded at a density of 0.4 million cells per ml. One day prior to transfection, cells were seeded at 0.6 million cells per ml. On day 0, cells were transfected with antibody expression plasmids encoding the light chain and heavy chain using MaxCyte electroporation platform following the instruction manual.
  • Additional Cell Boost 4 (final concentration: 2 g/L), Cell Boost 7b (final concentration: 0.1 g/L), and GlutaMAX (final concentration: 2 mM) was added on days 3 and 5, and supernatant was collected on day 7.
  • the culture media glucose level was monitored using glucose meters, and additional glucose was added to the culture when the glucose level was below 2 g/L.
  • Viable cell count and viability were measured by Vi-Cell instrument.
  • Antibody production was measured by Octet using Protein G sensors. Stable bulk pool generation - The expression plasmid was linearized using Pvu I (NEB) digestion for four hours.
  • the DNA was purified using phenol:chloroform:isoamyl alcohol extraction and dissolved in endotoxin-free water at the concentration of 2.5 ⁇ g/ ⁇ l.
  • Platform cell line 301-20 was maintained in EX-CELL 302 supplemented with 3 mM L-glutamine and 3 mM GlutaMAX. Cells were passaged every 3 to 4 days seeded at a density of 0.3 x 10 6 /ml. One day prior to transfection, cells were seeded at 0.6 x 10 6 /ml. On day 0, 15 x 10 6 cells were transfected with 25 ⁇ g of linearized antibody expression plasmids using MaxCyte electroporation (OC-100) platform following the instruction manual.
  • OC-100 MaxCyte electroporation
  • Example 8 Purification of Antibodies from EuCODE Expression System Clarified Cell culture media containing the target antibody containing non-natural amino acid pAF was loaded over a protein A MabSelect PrismA column (Cytiva) equilibrated in 20 mM sodium phosphate, 100 mM sodium chloride, pH 7.5. After loading, the column was washed with buffer A (20 mM sodium phosphate, 100mM sodium chloride, pH 7.5) followed by wash buffer B (50 mM sodium acetate, pH 5.5) to remove host cell contaminants. The target antibody was eluted from the column with elution buffer C (50 mM sodium acetate, pH 3.8).
  • buffer A (20 mM sodium phosphate, 100mM sodium chloride, pH 7.5
  • wash buffer B 50 mM sodium acetate, pH 5.5
  • the target antibody was pooled, and pH adjusted to pH 5.0 with 2.0 M tris base.
  • the target antibody was further purified by loading the conditioned protein A pool over a Capto SP Impres column (Cytiva) equilibrated in 50 mM sodium acetate, pH 5.0.
  • the target antibody was eluted from the column with a linear gradient to 100% buffer B (50 mM sodium acetate, 0.5 M sodium chloride, pH 5.0) and fractions containing Example 9: TROP2 cell surface expression TROP2 cell surface levels were quantified using the Dako QIFIKIT (Agilent, Santa Clara, CA) according to the manufacturer’s instruction.
  • cells were harvested using StemPro Acccutase cell dissociation reagent, washed with FACS buffer (1x PBS containing 0.2% BSA and 15 mM NaN3), and incubated with mouse anti-TROP2 antibody (clone MR54, eBioScience, San Diego, CA) or isotype control antibody (mouse IgG2a, kappa, eBioScience). After washing, FITC conjugated anti-mouse secondary antibody provided by kit was incubated with cells, set-up beads, and calibration beads. Washed cells and beads were run on FACSCantoII. Lot specific calibration beads were used to generate a standard curve to calculate TROP2 number on the surface of each cell line.
  • TROP2 cell surface numbers were determined as shown in Table 11. Table 11. TROP2 expression level on various cancer cell lines WSGR Ref. No: 31362-826.601
  • Example 10 HER3 cell surface expression HER3 surface levels were quantified using the Dako QIFIKIT (Agilent, Santa Clara, CA) according to the manufacturer’s instructions. Cells were incubated with mouse anti-HER3 antibody (BioLegend, San Diego, CA, Cat#324702) or isotype control antibody and detected with FITC conjugated anti-mouse secondary antibody provided by the kit. The calibration beads were used to generate a standard curve to calculate the surface HER3 numbers on the cells (Table 12). Table 12.
  • Example 11 In vitro cytotoxicity of ADCs containing anti-HER3 antibody conjugated to compound 10 or 16 (DAR > 3).
  • Table 13 EC 50 (nM) and Emax (%) in HCC1569 cell line in 3D culture system.
  • Table 14. EC50 (nM) and Emax (%) in A375 cell line in 3D culture system.
  • Table 15. EC 50 (nM) and Emax (%) in HCC827 cell line in 3D culture system.
  • Example 12 In vitro cytotoxicity of ADCs containing anti-TROP2 antibody conjugated to compound 10 (DAR > 3) in multiple cancer cell lines.
  • Cytotoxicity of anti-TROP2- HA114/LS121-Compound-10 was tested in multiple cancer cell lines with various TROP2 surface expression levels.
  • Cells were seeded into 96-well clear bottom white wall plate at 2,500 cells/well for BxPC-3, MDA-MB-468, and Calu-6 cells, or at 2,000 cells/well for HCC1806 cells and incubated overnight in a 37 °C, 5% CO 2 incubator.
  • the next day serially diluted anti-TROP2-HA114/LS121-Compound- 10 or Exatecan mesylate was added to the wells, and the plates were incubated for 7 days.
  • the IC 50 values of anti-TROP2-HA114/LS121-Compound-10 were in the range of 0.33-1.73 nM in TROP2-expressing BxPC-3, MDA-MB-468 and HCC1806 cell lines after 7 days of treatment; the IC 50 of anti-TROP2-HA114/LS121-Compound-10 in the TROP2-negative Calu-6 cell line was 17.58 nM (see Table 17 and FIGS.5A-5D). Table 17. IC50 (nM) and Emax (%) at 100 nM of anti-TROP2-HA114/LS121-Compound-10 in Multiple Cancer Cell Lines WSGR Ref.
  • Example 13 In vitro Cytotoxicity of anti-TROP2-HA114/LS121-Compound-10 in Human Keratinocytes.
  • Primary human keratinocytes (ATCC, Cat# PCS-200-011) were maintained in Dermal Cell Basal Medium (ATCC, Cat# PCS-200-030) supplemented with Keratinocyte Growth Kit (ATCC, Cat# PCS-200-400). Keratinocytes were seeded at 4,000 cells/well into 96-well clear bottom white wall plate and incubated overnight in a 37 °C, 5% CO2 incubator. The next day, cells were treated with serially diluted anti-TROP2-HA114/LS121-Compound-10 or Exatecan mesylate for 7 days.
  • Anti-TROP2-HA114/LS121-Compound-10 showed an IC50 value of 13.55 nM against TROP2- expressing human keratinocytes; the Emax was 60.40% when cells were treated with the ADC at a concentration of 100 nM.
  • Example 14 Anti-CD70, Anti-HER2 and Anti-PSMA Antibodies and Variants Thereof, and ADCs.
  • Anti-CD70, anti-HER2 and anti-PSMA antibodies and variants thereof of the present disclosure, and ADCs of the present disclosure containing said antibodies and variants thereof, can be prepared as described in WO2013/192360A1, WO2022/212899A1 and WO2019/191728A1, the entire contents of each of which are hereby incorporated by reference in their entirety, and/or by adapting methods expressly disclosed herein.
  • Non-limiting Numbered Embodiments of the invention are listed below.
  • ADC An antibody-drug conjugate (ADC) of Formula (I): wherein Drug has the following structure: WSGR Ref.
  • each L3 independently comprises a MC (6-maleimidocaproyl), a MCC (a maleimidomethyl cyclohexane-1-carboxylate), a MP (maleimidopropanoyl), a PAB (p-aminobenzyloxycarbonyl), a SPP (N-Succinimidyl 4-(2-pyridylthio) pentanoate), a SMCC (N-Succinimidyl 4-(N- maleimidomethyl)cyclohexane-1 carboxylate), or a SIAB (N-Succinimidyl (4-iodo- acetyl)aminobenzoate); each Linker is independently absent, (CH 2 ) v [**], CH 2 -O-(CH 2 ) v [**], (CH 2 ) v -O-
  • ADC of embodiment A1, wherein Drug has the following structure: . A3.
  • the ADC of embodiment A1, wherein Drug has the following structure: WSGR Ref. No: 31362-826.601 .
  • A4. The ADC of any one of embodiments A1 to A3, wherein the antibody, antibody fragment or variant thereof comprises one or more non-natural amino acids.
  • A5. The ADC of any one of embodiments A1 to A4, wherein the antibody, antibody fragment or variant thereof is configured to bind to an antigen.
  • the ADC of any one of embodiments A1 to A5, wherein the antibody, antibody fragment or variant thereof is configured to bind to a tumor-associated antigen (TAA) or cancer antigen.
  • TAA tumor-associated antigen
  • A8 The ADC of any one of embodiments A1 to A6, wherein Ab comprises a heavy chain having a heavy chain sequence, a light chain having a light chain sequence, or both.
  • A9 The ADC of embodiment A8, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids.
  • A10 The ADC of embodiment A8 or A9, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids.
  • A11 The ADC of any one of embodiments A1 to A10, wherein Ab comprises two heavy chains, each heavy chain having a heavy chain sequence, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acid.
  • ADC of any one of embodiments A1 to A11 wherein Ab comprises two light chains, each light chain having a light chain sequence, wherein each light chain sequence comprises at least one of the one or more non-natural amino acid; optionally, wherein Ab comprises two heavy chains and two light chains, wherein each heavy chain sequence and each light chain sequence comprises at least one of the one or more non-natural amino acid.
  • Ab comprises two light chains, each light chain having a light chain sequence, wherein each light chain sequence comprises at least one of the one or more non-natural amino acid; optionally, wherein Ab comprises two heavy chains and two light chains, wherein each heavy chain sequence and each light chain sequence comprises at least one of the one or more non-natural amino acid.
  • each of the one or more non-natural amino acids is independently selected from the group consisting of para-acetyl phenylalanine, 4- acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)), 3-O-(N-acetyl-beta-D-glucosaminyl)- acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L- tyrosine, 3-amino-L-tyrosine, 4-azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, 4-benzoyl-L-phenylalanine,
  • A14 The ADC of any one of embodiments A1 to A13, wherein Ab is conjugated to the terminal arm of L3 via an oxime bond.
  • A15 The ADC of any one of embodiments A4 to A14, wherein at least one of the non-naturally occurring amino acids is para-acetyl phenylalanine; optionally, wherein at least one of the non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)).
  • A16 The ADC of any one of embodiments A4 to A15, wherein each of the one or more non-natural amino acids is the same. WSGR Ref. No: 31362-826.601 A17.
  • each of the one or more non-natural amino acids is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L- phenylalanine (para-acetyl-L-phenylalanine (pAF)).
  • pAF para-acetyl-L-phenylalanine
  • A18. The ADC of any one of embodiments A1 to A17, wherein the antibody, antibody fragment or variant thereof comprises 1, 2, 3 or 4 non-natural amino acids.
  • anti-TROP2 anti-trophoblast antigen 2
  • the anti-TROP2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 5, and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17.
  • the ADC of embodiment A21 wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1 and 2, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. A23.
  • the anti-HER2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 25 and 26, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 27 and 28.
  • the ADC of embodiment A31, wherein the anti-PSMA antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 and 45 (Table 4).
  • the anti-PSMA antibody comprises a heavy chain sequence and a light chain sequence
  • the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 29, 34, 36, 38, 40, 42 and 44 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45.
  • the heavy chain sequence comprises an amino acid of SEQ ID No: 36
  • the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45.
  • the ADC of embodiment A34 wherein the heavy chain sequence comprises an amino acid of SEQ ID No: 36, and wherein the light chain sequence comprises an amino acid sequence of SEQ ID NO: 37.
  • A36 The ADC of any one of embodiments A1 to A28, wherein Ab is an anti-HER3 antibody.
  • the ADC of embodiment A37, wherein the anti-HER3 antibody comprises a sequence selected from the group consisting of SEQ ID NO: 46 to 58 (Table 5).
  • the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence
  • the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 46 or 58
  • the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57.
  • the ADC of embodiment A37 wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57. WSGR Ref. No: 31362-826.601 A40.
  • the ADC of embodiment A40 wherein the anti-HER3 antibody comprises two heavy chain sequences and two light chain sequences, wherein each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 50.
  • A42 The ADC of embodiment A40 or A41, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 50.
  • A43 The ADC of any one of embodiments A36 to A39, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and the light chain sequence comprises an amino acid sequence of SEQ ID NO: 51.
  • A44 The ADC of embodiment A43, wherein the anti-HER3 antibody comprises two heavy chain sequences and two light chain sequences, wherein each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 51.
  • A45 The ADC of embodiment A43 or A44, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 51.
  • a pharmaceutical composition comprising an ADC of any one of embodiments A1 to A45 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. B1.
  • ADC antibody-drug conjugate of Formula (V) or (VI): WSGR Ref. No: 31362-826.601
  • Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids
  • L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate;
  • E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O) nn –, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, , wherein each nn is independently an integer from 1 to 100; wherein each R w is independently H or C 1 -C 8 alkyl; and combinations thereof; optionally, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(Rw
  • B6 The ADC of any one of embodiments B1 to B5, wherein Ab comprises a heavy chain having a heavy chain sequence, a light chain having a light chain sequence, or both.
  • B7 The ADC of embodiment B6, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids.
  • B8 The ADC of embodiment B6 or B7, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids.
  • B9 The ADC of any one of embodiments B1 to B8, wherein Ab comprises two heavy chains, each heavy chain having a heavy chain sequence, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acid.
  • ADC of any one of embodiments B1 to B9, wherein Ab comprises two light chains, each light chain having a light chain sequence, wherein each light chain sequence comprises at least one of the one or more non-natural amino acid.
  • B11, wherein Ab comprises two heavy chains and two light chains, wherein each heavy chain sequence and each light chain sequence comprises at least one of the one or more non-natural amino acid.
  • B12 The ADC of any one of embodiments B1 to B11, wherein E is selected from the group consisting of: WSGR Ref.
  • B13 The ADC of any one of embodiments B1 to B12, wherein E is: wherein Rc is unsubstituted C1-C6 alkyl; optionally, Rc is methyl.
  • B16 The ADC of any one of embodiments B1 to B15, wherein at least one of the non-naturally occurring amino acids is para-acetyl phenylalanine; optionally, wherein at least one of the non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)).
  • B17 The ADC of any one of embodiments B1 to B16, wherein each of the one or more non-natural amino acids is the same. B18.
  • each of the one or more non-natural amino acids is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L- phenylalanine (para-acetyl-L-phenylalanine (pAF)).
  • B19. The ADC of any one of embodiments B1 to B18, wherein the antibody, antibody fragment or variant thereof comprises 1, 2, 3 or 4 non-natural amino acids.
  • B20. The ADC of any one of embodiments B1 to B19, wherein d is 1, 2, 3 or 4. B21.
  • ADC of any one of embodiments B1 to B21 wherein Ab comprises two heavy chains and two light chains, each said heavy chain having a heavy chain sequence and each said light chain having a light chain sequence, wherein each said heavy chain sequence and each said light chain sequence comprises one non-natural amino acid; and d is 4.
  • L consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and WSGR Ref.
  • No: 31362-826.601 at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid; , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C 1 -C 8 alkyl; and combinations thereof; optionally, each R w is independently H or methyl.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid; , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C 1 -C 8 alkyl; and combinations thereof; optionally, each R w is independently H or methyl
  • each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and each *, when present, denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI).
  • each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–
  • each nn is independently an integer from 1 to 100
  • each nn is independently an integer from 1 to 10
  • each i is independently 0 or 1
  • each * when present, denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI).
  • No: 31362-826.601 each * denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI).
  • B26 The ADC of embodiment B25, wherein L is selected from the group consisting of: wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI); and each + denotes connection to E. B27.
  • each alkylene when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each m, when present, is independently 1, 2 or 3; each n is independently 1, 2 or 3; and each q, when present, is independently 1, 2 or 3.
  • B29. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-trophoblast antigen 2 (anti-TROP2) antibody.
  • anti-TROP2 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17 (Table 1).
  • the anti-TROP2 antibody comprises a heavy chain sequence and a light chain sequence
  • the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 5, and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, and 17.
  • the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1 and 2
  • the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17.
  • the ADC of embodiment B31 wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 5 and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17.
  • B34 The ADC of embodiment B31, B32 or B33, wherein the heavy chain sequence comprises at least one non-natural amino acid.
  • B35 The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-CD70 antibody.
  • B36 The ADC of embodiment B35, wherein the anti-CD70 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 18, 19, 20, 21, 22, 23 and 24 (Table 2). B37.
  • the ADC of embodiment B36 wherein the anti-CD70 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 18 and 20, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24.
  • the ADC of embodiment B38, wherein the anti-HER2 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 25, 26, 27 and 28 (Table 3). B40.
  • the ADC of embodiment B39, wherein the anti-HER2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 25 and 26, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 27 and 28.
  • B41. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-PSMA antibody.
  • the ADC of embodiment B41, wherein the anti-PSMA antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 and 45 (Table 4).
  • B43 The ADC of embodiment B41, wherein the anti-PSMA antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44
  • the anti-PSMA antibody comprises a heavy chain sequence and a light chain sequence
  • the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 29, 34, 36, 38, 40, 42 and 44 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45.
  • the heavy chain sequence comprises an amino acid of SEQ ID No: 36
  • the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45.
  • B46. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-HER3 antibody.
  • the ADC of embodiment B46, wherein the anti-HER3 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 46 to 58 (Table 5). B48.
  • the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 46 or 58 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57. B49.
  • the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid WSGR Ref.
  • each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 50.
  • B52 The ADC of embodiment B50 or B51, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 50.
  • B53 The ADC of any one of embodiments B46 to B49, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and the light chain sequence comprises an amino acid sequence of SEQ ID NO: 51.
  • each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 51.
  • B55 The ADC of embodiment B53 or B54, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 51.
  • B56 The ADC of any one of embodiments B1 to B55, wherein the ADC is an ADC of Formula (V): . B57.
  • B58. The ADC of embodiment B57, wherein n is 1, 2 or 3; optionally, wherein n is 2.
  • B59. The ADC of embodiment B57 or B58, wherein E is: ; wherein + denotes connection to (CH2)n; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl; optionally, wherein Rc is methyl.
  • Va ADC of Formula (Va): WSGR Ref. No: 31362-826.601 ; wherein n is an integer from 1 to 10.
  • B58. The ADC of embodiment B57, wherein n is 1, 2 or 3; optionally, wherein n is 2.
  • B59. The ADC of embodiment B57 or B58,
  • E is: ; wherein + denotes connection to (CH2CH2O)m; the wavy line denotes connection to Ab; and R c is unsubstituted C 1 -C 6 alkyl; optionally, wherein, R c is methyl.
  • B66 is
  • a pharmaceutical composition comprising an ADC of any one of embodiments B1 to B66 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • a pharmaceutical composition comprising a compound of any one of embodiments C1 to C11 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • Drug has the following structure: n is independently 1 or 2; Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; X is independently O or S; each L1 is independently absent, * (CH 2 ) m , * CH 2 -O-(CH 2 ) m , * (CH 2 ) m -O-CH 2 , * C(O)-(CH 2 ) m , * NH-(CH 2 ) m , * (CH 2 ) m (OCH 2 CH 2 ) k , * NH-(CH 2 ) m (OCH 2 CH 2 ) k , unsubstituted C 1 -C 6
  • a pharmaceutical composition comprising a compound of any one of embodiments D1 to D3 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • L3 is H 2 N-O-(CH 2 ) s -C(O) , H 2 N-O-(CH 2 ) s , H 2 N-O-(CH 2 CH 2 O) s -CH 2 CH 2 C(O) , maleimidyl-(CH 2 ) s -C(O) , maleimidyl-(CH 2 ) s , maleimidyl-(CH 2 CH 2 O) s CH 2 CH 2 C(O) , Br-CH 2 - wherein s is 1, 2, 3, 4, 5 or 6 and Y1 is OH or a leaving group; and each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- alkylene or C 1 -C 6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**
  • a pharmaceutical composition comprising a compound of any one of embodiments E1 to E3 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety; optionally, W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, -C(O)CH 2 NH 2 , an activated ester, –O–NH 2 , a maleimide, a tetrazine, an alkyne, a cyclooctyne or
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, wherein each nn is independently an integer from 1 to 100; wherein each R w is independently H or C 1 -C 8 alkyl; and combinations thereof; optionally, arylene is phenylene.
  • each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –, -O-, -C(O)- and - N(Rw)-, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof.
  • F5. The compound of embodiment F3 or F4, wherein each R w is independently H or methyl.
  • F6 The compound of any one of embodiments F1 to F5, wherein W is selected from the group consisting of: WSGR Ref.
  • L consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and optionally, at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –,-O-, - C(O)-, -N(Rw)- and an amino acid; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl.
  • a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate
  • at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –,-O-, - C(O)-, -N(Rw)
  • each U is independently: . F12.
  • L consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O) nn –,-O-, -C(O)- and - WSGR Ref.
  • each J is independently: each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH 2 ) 8 –, –(CH 2 ) 9 –, –(CH 2 ) 10 –, –(CH 2 ) 11 – and –(CH 2 ) 12 –; each nn is independently an integer from 1 to 100; optionally, each nn is
  • each alkylene when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; and each n is independently 1, 2 or 3.
  • F21 The compound of any one of F9 to F20, wherein i is 1.
  • F22. The compound of any one of embodiments F1 to F21, wherein the compound is a compound of Formula (VII): WSGR Ref. No: 31362-826.601 ; or a pharmaceutically acceptable salt thereof.
  • the compound of embodiment F22 having the following structure: or a pharmaceutically acceptable salt thereof.
  • F24 The compound of any one of embodiments F1 to F21, wherein the compound is a compound of Formula (VIII): ; or a pharmaceutically acceptable salt thereof.
  • F25 The compound of embodiment F24 having the following structure: WSGR Ref. No: 31362-826.601 or a pharmaceutically acceptable salt thereof.
  • F26 A pharmaceutical composition comprising a compound of any one of embodiments F1 to F25 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. G1.
  • the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 1
  • the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 1.
  • each light chain sequence comprises at least one of the one or more non-natural amino acids
  • the position occupied by each of the one or more non-natural amino acid in each light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position occupied by each at least one non-natural amino acid in each light chain sequence is position 121.
  • each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 157, 168, 172, 202 and 205; optionally, the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)).
  • the ADC of embodiment G11, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 2.
  • the ADC of embodiment G12, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 2, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 2.
  • the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 2
  • the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 2.
  • the ADC of embodiment G13 wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114.
  • G15 The ADC of embodiment G14, wherein the heavy chain comprises one non-natural amino acid.
  • the ADC of embodiment G13, G14 or G15 wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each at least one non- natural amino acid in the light chain sequence is independently selected from the group consisting of position 110, 112, 114 and 121; optionally, the position occupied by one of the one or more non- natural amino acid in the light chain sequence is position 121.
  • G17 The ADC of any one of embodiment G1 to G16, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises two heavy chain sequences, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each heavy chain sequence is Kabat position 114.
  • G18 The ADC of embodiment G17, wherein the heavy chain comprises one non-natural amino acid.
  • G19. The ADC of embodiment G17 or G18, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each at least one non-natural amino acid in each light chain sequence is independently selected from the group consisting of position 110, 112, 114 and 121; optionally, the position occupied by one of the one or more non-natural amino acid in each light chain sequence is position 121. G20.
  • each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 157, 168, 172, 202 and 205; optionally, the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)).
  • G21 The ADC of any one of embodiments A1 to A18 or B1 to B28 and B56 to B66, wherein Ab is an anti-HER2 antibody, antibody fragment or variant thereof.
  • the ADC of embodiment G21, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 3.
  • the ADC of embodiment G22, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 3, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 3.
  • the ADC of embodiment G23 wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114.
  • G25 The ADC of embodiment G24, wherein the heavy chain comprises one non-natural amino acid.
  • G26 The ADC of embodiment G23, G24 or G25, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G27.
  • G28. The ADC of embodiment G27, wherein the heavy chain comprises one non-natural amino acid.
  • the ADC of embodiment G27 or G28, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each light chain sequence is position 110121. G30.
  • each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)).
  • each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L
  • the ADC of embodiment G31, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 4.
  • the ADC of embodiment G32, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 4, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 4.
  • the ADC of embodiment G33 wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114.
  • G35 The ADC of embodiment G34, wherein the heavy chain comprises one non-natural amino acid.
  • G36 The ADC of embodiment G33, G34 or G35, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G37.
  • G38. The ADC of embodiment G37, wherein the heavy chain comprises one non-natural amino acid.
  • the ADC of embodiment G37 or G38, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each light chain sequence is position 110, 121. G40.
  • each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is position 121; or each light chain does not contain a non-natural amino acid (each light chain amino acid sequence consists of naturally-occurring amino acids, or more particularly, natural amino acids selected from the group consisting of the twenty canonical amino acids; WSGR Ref.
  • each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)).
  • G41. The ADC of any one of embodiments A1 to A18, B1 to B28 and B56 to B66, wherein Ab is an anti-HER3 antibody, antibody fragment or variant thereof.
  • the ADC of embodiment G41, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 5.
  • the ADC of embodiment G42 wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 5, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 5.
  • the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114.
  • G45. The ADC of embodiment G44, wherein the heavy chain comprises one non-natural amino acid.
  • the ADC of embodiment G43, G44 or G45 wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each of the one or more non-natural amino acid in the light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G47.
  • each light chain sequence comprises at least one of the one or more non-natural amino acids
  • the position occupied by each at least one non-natural amino acid in each light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position WSGR Ref. No: 31362-826.601 occupied by one of the one or more non-natural amino acid in each light chain sequence is position 121. G50.
  • the ADC of any one of embodiments G47 to G49, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises two heavy chain sequences of SEQ ID NO: 58 and two light chain sequences of SEQ ID NO: 50.
  • the ADC of any one of embodiments G47 to G49, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises two heavy chain sequences of SEQ ID NO: 58 and two light chain sequences of SEQ ID NO: 51.
  • a pharmaceutical composition comprising an ADC of any one of embodiments G1 to G51 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. H1.
  • linker of embodiment H1 wherein i is 1. H3.
  • a pharmaceutical composition comprising a drug-linker compound of any one of embodiments I1 to I8 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • An ADC composition comprising or consisting essentially of: (a) an ADC of any one of embodiments A1 to A45, wherein p is 1; (b) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 2; WSGR Ref.
  • ADC composition of embodiment J1 wherein the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, at least about 2 and at most about 4, or at least about 3 and at most about 4. J3.
  • An ADC composition of embodiment J1 consisting essentially of: (a) an ADC of any one of embodiments A1 to A45, wherein p is 1; (b) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 2; (c) an ADC of any one of embodiments A1 to A45), wherein the ADC is identical to (a), except that p is 3; (d) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. J4.
  • a pharmaceutical composition comprising an ADC of any one of embodiments J1 to J5 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
  • K1 An ADC composition comprising or consisting essentially of: WSGR Ref.
  • the ADC composition of embodiment K1 wherein the ADC composition is characterized as having a DAR of at least about 1 and at most about 8, at least about 2 and at most about 8, at least about 2 and at most about 6, at least about 2 and at most about 4, or at least about 3 and at most about 4. K3.
  • each ADC is a compound of Formula (VI).
  • K9 The ADC of any one of embodiments K1 to K8, wherein the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. K10.
  • a pharmaceutical composition comprising an ADC of any one of embodiments K1 to K9 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only and are not intended to limit the scope of the disclosure. Indeed, the novel compositions, methods and systems described herein may be embodied in a variety of other forms.
  • No: 31362-826.601 various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as a subcombination or variation of a subcombination. The features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. Also, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described components and systems can generally be integrated together in a single product or packaged into multiple products.
  • No: 31362-826.601 achieves a desired result.
  • the terms “approximately”, “about”, “generally,” “substantial” and “substantially'' may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of: within less than 0.1% of, and within less than 0.01% of the stated amount.
  • the term “comprising” is open ended, and the broadest reasonable interpretation of the term applies. The present disclosure contemplates alternative embodiments wherein the term “consisting of” can be used in place of each recitation of the term “comprising” herein.

Landscapes

  • Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Organic Chemistry (AREA)
  • Immunology (AREA)
  • General Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Biochemistry (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Molecular Biology (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Biophysics (AREA)
  • Genetics & Genomics (AREA)
  • Epidemiology (AREA)
  • Cell Biology (AREA)
  • Reproductive Health (AREA)
  • Pregnancy & Childbirth (AREA)
  • Gynecology & Obstetrics (AREA)
  • Oncology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Peptides Or Proteins (AREA)

Abstract

Disclosed herein are antibody drug conjugates (ADCs), drug-linkers for ADCs, and tunable phosphate-based linkers. ADCs of the present disclosure include antibodies such as anti-HER3 and anti-TROP2 antibodies conjugated to exatecan drugs via phosphate-based linkers. Also disclosed are methods and compositions for using ADCs in inhibiting, preventing or treating diseases or conditions such as cancer.

Description

WSGR Ref. No: 31362-826.601 DRUG LINKERS AND ANTIBODY CONJUGATES THEREOF CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims priority to U.S. Provisional Application No.63/496,236 filed on April 14, 2023, the entire contents of which are hereby incorporated herein in their entirety. REFERENCE TO A SEQUENCE LISTING The present application contains a Sequence Listing which has been submitted electronically in XML format and is hereby incorporated by reference in its entirety. The XML copy, created on March 30, 2024, is named AMBX-0241_00PCT.xml and is 79,778 bytes in size. BACKGROUND Antibody-drug conjugates (ADCs) are a potent class of therapeutic constructs advancing the field of cancer therapeutics by allowing targeted delivery of cytotoxic agents to target cells, such as cancer cells. Currently, only a few ADCs have been approved for therapeutic use including gemtuzumab ozogamicin for AML (subsequently withdrawn from the market), brentuximab vedotin for ALCL and Hodgkin lymphoma, and trastuzumab emtansine for HER2-positive metastatic breast cancer (Verma et al., N Engl J Med 367:1783-91, 2012; Bross et al., Clin Cancer Res 7:1490-96, 2001; Francisco et al., Blood 102:1458-65, 2003); and sacituzumab govitecan for metastatic triple negative breast cancer (TNBC) (Zaman et al., OncoTargets and Therapy 12: 1781-1790, 2019). However, ADCs face challenges due to lack of therapeutic index and toxicity. The linker technology for attachment of the cytotoxic drug to an antibody impacts the stability of ADCs during the systemic circulation. Therefore, there is a need in the art to design improved linkers such as phosphate-based linkers and drug design for antibody conjugation. The present disclosure provides phosphate-based linkers with tunable stability for intracellular delivery of drug conjugates. The phosphate-based linkers have differentiated and tunable stability in blood versus an intracellular environment and can further include a self- immolating linker. Antibody-drug conjugates that comprise these linkers are stable in circulation (plasma/blood) but reactive or cleavable in intracellular compartments, such as lysosomal compartments, making them useful for intracellular delivery, the rate being dependent on the structure of the tuning element. SUMMARY OF THE INVENTION The present invention provides novel ADCs comprising phosphate-based linkers for drug design and for antibody conjugation. WSGR Ref. No: 31362-826.601 In some general aspects, the present disclosure provides an antibody-drug conjugate (ADC) of Formula (I):
Figure imgf000003_0001
wherein Drug has the following structure:
Figure imgf000003_0002
each n is independently 1 or 2; p is 1, 2, 3, 4, 5, 6, 7 or 8; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , C3-C6 cyclic alkylene, * (OCH2CH2)m , unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1- C3 alkoxy; wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5 or 6; each L2 is independently absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene, or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6 and each j is independently 0, 1, 2, 3, 4, 5 or 6; and WSGR Ref. No: 31362-826.601 each L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, each q is independently 1, 2, 3, 4, 5 or 6, and each r is independently 1, 2, 3, 4, 5 or 6; or L2b is selected from the group consisting of:
Figure imgf000004_0001
, wherein [*] denotes connection to L3, and each Z1 is independently C(H) or N; each L3 is independently [**]=N-O-(CH2)s-C(O)-NH , [**]=N-O-(CH2)s-C(O) , [**]=N-O- (CH2)s , [**]=N-O-(CH2)s-O , [**]=N-O-(CH2CH2O)s-CH2CH2C(O) , [**] S-succinimidyl- (CH2)s-C(=O) , [**] S-succinimidyl-(CH2)s , [**] S-succinimidyl-(CH2CH2O)sCH2CH2C(O) , [**] S-CH2-(CO) , [**] NH-C(=O)-(CH2)sC(O) , or [**] NH-C(O)-(CH2CH2O)s-CH2CH2C(O) , wherein [**] denotes connection to Ab and each s is independently 1, 2, 3, 4, 5 or 6; or each L3 independently comprises a 6-maleimidocaproyl, a maleimidomethyl cyclohexane-1- carboxylate, a maleimidopropanoyl, a p-aminobenzyloxycarbonyl, a N-succinimidyl 4-(2- pyridylthio) pentanoate, a N-succinimidyl 4-(N-maleimidomethyl)cyclohexane-1 carboxylate or a N- succinimidyl (4-iodo-acetyl)aminobenzoate; each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- CH2 [**], (CH2)v-C(O) [**], O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**], O-CH2- O-C(O) [**], NH-(CH2)v [**], (CH2)v(OCH2CH2)w [**], (OCH2CH2)w-(CH2)v [**], (CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; and Ab is an antibody, antibody fragment or variant thereof. In some embodiments, Drug has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000005_0001
wherein the wavy line denotes connection to Linker. In some embodiments, Drug has the following structure:
Figure imgf000005_0002
wherein the wavy line denotes connection to Linker. In some other general aspects, the present disclosure provides an antibody-drug conjugate (ADC) of Formula (V) or (VI):
Figure imgf000005_0003
wherein: Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids; L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof. WSGR Ref. No: 31362-826.601 In some embodiments, the phosphate-based moiety is a pyrophosphate ester. In some other embodiments, the phosphate-based moiety is a diphosphonate. In some embodiments, L further comprises at least one additional moiety, wherein each of the at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, - C(O)-, -N(Rw)-, -S(O)0-2-, and an amino acid, and any combination thereof; wherein each Rw is independently H or C1-C8 alkyl, wherein each nn is independently an integer from 1 to 100; optionally, each arylene is phenylene. In some embodiments, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)-, and -N(Rw)-, and any combination thereof; wherein each Rw is independently H or C1-C8 alkyl; and wherein each nn is independently an integer from 1 to 100. In some embodiments, each Rw is independently H or methyl. In some embodiments, E comprises an amide, an ester, a thioester, a pyrrolidine-2,5-dione, an oxime, a 4,5-dihydro-1,2,3-triazole or a 1,4-dihydropyridazine, wherein the 4,5-dihydro-1,2,3- triazole or 1,4-dihydropyridazine is optionally fused to an 8-membered ring. In some embodiments, E is selected from the group consisting of:
Figure imgf000006_0001
WSGR Ref. No: 31362-826.601
Figure imgf000007_0001
wherein: each Rb is independently H or unsubstituted alkyl; each Rc is unsubstituted alkyl; each Rf is independently H or unsubstituted alkyl, each s is independently 0, 1, 2, 3, 4, 5 or 6, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to L; and each wavy line denotes connection to Ab. In some embodiments, each Rb is independently H or unsubstituted C1-C6 alkyl, each Rc is unsubstituted C1-C6 alkyl, and each Rf is independently H or unsubstituted C1-C6 alkyl. In some embodiments, E is: ; wherein Rc is unsubstituted C1-C6 alkyl. In some embodiments, Rc is methyl. In some embodiments, L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each of the at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(Rw)- and an amino acid; and combinations thereof; wherein each Rw is independently H or C1-C8 alkyl; and wherein each nn is independently an integer from 1 to 100; optionally, each Rw is independently H or methyl. In some embodiments, L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, WSGR Ref. No: 31362-826.601 *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–U–alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, WSGR Ref. No: 31362-826.601 –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–; wherein: each U is -NH-AA-C(O)-, wherein each AA is independently an amino acid; each J is independently:
Figure imgf000009_0001
; each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; optionally, each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and each *, when present, denotes the connection of L to (a) -N(H)- of Formula (V), or (b) the -O- of Formula (VI). In some embodiments, each U is independently:
Figure imgf000009_0002
. In some embodiments, L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, WSGR Ref. No: 31362-826.601 *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn– and *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: each J is independently:
Figure imgf000010_0001
; each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and each * denotes the connection of L to (a) -N(H)- of Formula (V), or (b) -O of Formula (VI). In some embodiments, L is selected from the group consisting of:
Figure imgf000010_0002
WSGR Ref. No: 31362-826.601
Figure imgf000011_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection of L to (a) -N(H)- of Formula (V), or (b) -O- of Formula (VI); and each + denotes connection to E. In some embodiments, In some embodiments, each alkylene, when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each m, when present, is independently 1, 2 or 3; each n is independently 1, 2 or 3; and each q, when present, is independently 1, 2 or 3. In some embodiments, the ADC is an ADC of Formula (V):
Figure imgf000011_0002
. In some embodiments, the ADC is an ADC of Formula (VI): WSGR Ref. No: 31362-826.601
Figure imgf000012_0001
. In some embodiments, d is 1, 2, 3 or 4. In some embodiments, Ab comprises one or more non-natural amino acids. In some embodiments, Ab is configured to bind to an antigen. In some embodiments, Ab is configured to bind to a tumor-associated antigen (TAA) or cancer antigen. In some embodiments, Ab binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA-125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha and MN/CA IX. In some embodiments, Ab binds to an antigen selected from the group consisting of TROP2, CD70, HER2, HER3 and PSMA. In some embodiments, each of the one or more non-natural amino acids, is independently selected from the group consisting of para-acetyl phenylalanine, 4-acetyl-L-phenylalanine (para- D-glucosaminyl)-L-asparagine, O-allyl-L-tyrosine, alpha-N-acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3- amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L-tyrosine, 3-amino-L-tyrosine, 4- azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin-5yl)-L-alanine, 3-borono-L- phenylalanine, 4-borono-L-phenylalanine, 4-bromo-L-phenylalanine, p-carboxymethyl-L- phenylalanine, 4-carboxy-L-phenylalanine, p-cyano-L-phenylalanine, 3,4-dihydroxy-L- WSGR Ref. No: 31362-826.601 phenylalanine (L-DOPA), 4-ethynyl-L-phenylalanine, 2-fluoro-L-phenylalanine, 3-fluoro-L- phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl-beta-D-galactosaminyl)-L- serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L-phenylalanine, 4- isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O-mannopyranosyl-L- serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L-phenylalanine, 3- methyl-L-phenylalanine, O-methyl-L-tyrosine, 3-(2-naphthyl)-L-alanine, 5-nitro-L-histidine, 4- nitro-L-histidine, 4-nitro-L-leucine, 2-nitro-L-phenylalanine, 3-nitro-L-phenylalanine, 4-nitro-L- phenylalanine, 4-nitro-L-tryptophan, 5-nitro-L-tryptophan, 6-nitro-L-tryptophan, 7-nitro-L- tryptophan, 2-nitro-L-tyrosine, 3-nitro-L-tyrosine, O-phospho-L-serine, O-phospho-L-tyrosine, 4- propargyloxy-L-phenylalanine, O-2-propyn-1-yl-L-tyrosine, 4-sulfo-L-phenylalanine and O-sulfo- L-tyrosine. In some embodiments, at least one of the one or more non-natural amino acids is para- acetyl-L-phenylalanine (pAF). In some embodiments, each of the one or more non-natural amino acids is the same. In some embodiments, each of the one or more non-natural amino acids is para- acetyl-L-phenylalanine (pAF). In some embodiments, drug to antibody ratio is about 1, about 2, about 3 or about 4. In some embodiments, Ab comprises a heavy chain having a heavy chain amino acid sequence, a light chain having a light chain amino acid sequence, or both. In some embodiments, the heavy chain comprises at least one of the one or more non-natural amino acids. In some embodiments, the light chain comprises at least one of the one or more non-natural amino acids. In some embodiments, Ab comprises two heavy chains, wherein each heavy chain comprises at least one of the one or more non-natural amino acids. In some embodiments, Ab comprises two light chains; optionally, wherein each light chain comprises at least one of the one or more non-natural amino acids. In some embodiments, the one or more non-natural amino acids is 1, 2, 3 or 4 non- natural amino acids. In some embodiments, Ab comprises two heavy chains and two light chains, wherein each heavy chain comprises one non-natural amino acid. In some embodiments, each light chain comprises one non-natural amino acid. In some embodiments, Ab is an anti-trophoblast antigen 2 antibody (anti-TROP2 Ab), antibody fragment or variant thereof. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 1 to 17. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain amino acid sequence is selected from the group consisting of SEQ ID NOs: 5 and 6. In some embodiments, the heavy chain has the amino acid sequence of SEQ ID NO: 5, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, WSGR Ref. No: 31362-826.601 comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 11, wherein one non- natural amino acid occupies position 121. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, Ab is an anti-CD70 antibody (anti-CD70 Ab), antibody fragment or variant thereof. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 18 to 24. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 20, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 19. In some embodiments, wherein the light chain has the amino acid sequence of SEQ ID NO: 24, wherein one non-natural amino acid occupies position 121. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 20. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 19. In some embodiments, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 24. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, Ab is an anti-HER2 antibody (anti-HER2 Ab), antibody fragment or variant thereof. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 25 to 28. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 26, wherein WSGR Ref. No: 31362-826.601 one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof comprises a light chain. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 27. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 28, wherein one non-natural amino acid occupies position 121. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 26. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 27. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 28. In some embodiments, each non- natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, Ab is an anti-PSMA antibody (anti-PSMA Ab), antibody fragment or variant thereof. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 29 to 45. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 36, 38, 40, 42 and 44, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 37, 39, 41, 43 and 45. In some embodiments, the anti- PSMA Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 36. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises two light chains. In some embodiments, each light chain has the amino acid sequence of SEQ ID NO: 37. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, In some embodiments, Ab is an anti-HER3 antibody (anti-HER3 Ab), antibody fragment or variant thereof. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 46 to 58. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 58, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 47 to 57. In some embodiments, WSGR Ref. No: 31362-826.601 the light chain has the amino acid sequence of SEQ ID NO: 47. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 51, wherein one non-natural amino acid occupies position 121. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 47. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, the ADC disclosed herein is an ADC of Formula (V):
Figure imgf000016_0001
. In some embodiments, L is *-C(O)-O-CH2- O-P(=O)(OH)-O-P(=O)(OH)-O-CH2CH2-, wherein * denotes the connection of L to -N(H)- of Formula (V). In some embodiments, Ab is an anti-HER3 monoclonal antibody comprising two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58. In some embodiments, the ADC further comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51. In some embodiments, Ab is an anti-TROP2 monoclonal antibody comprising two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5. In some embodiments, the ADC further comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11. In some general aspects, the present disclosure provides a compound of Formula (VII) or (VIII): WSGR Ref. No: 31362-826.601
Figure imgf000017_0001
, or a pharmaceutically acceptable salt thereof; wherein: L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety. In some embodiments, W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, - C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein Rb is H or unsubstituted alkyl, Rc is unsubstituted alkyl, and Rd is H, unsubstituted alkyl or a carboxylic acid protecting group. In some embodiments, the phosphate- based moiety is a pyrophosphate ester or a diphosphonate. In some embodiments, L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, – (alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, and combinations thereof, wherein each Rw is independently H or C1-C8 alkyl; wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; optionally, arylene is phenylene. In some embodiments, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(Rw)-, and combinations thereof, wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10, and wherein each Rw is independently H or C1-C8 alkyl. In some embodiments, W is selected from the group consisting of: WSGR Ref. No: 31362-826.601
Figure imgf000018_0001
-N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, an activated ester, –O–NH2 and an optionally substituted monocyclic or polycyclic group comprising a cyclooctyne; wherein: Rb is H or unsubstituted C1-C6 alkyl, Rc is unsubstituted C1-C6 alkyl, Rd is H, unsubstituted C1-C6 alkyl or a carboxylic acid protecting group, Rf is H or unsubstituted C1-C6 alkyl, s is 0, 1, 2, 3, 4, 5 or 6, and t is 0, 1, 2, 3, 4, 5 or 6. In some embodiments, the optionally substituted monocyclic or polycyclic group comprising the cyclooctyne is selected from the group consisting of:
Figure imgf000018_0002
In some embodiments, W is –O–NH2. In some embodiments, L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid, and combinations thereof; wherein each Rw is independently H or C1-C8 alkyl; wherein each nn is independently an integer of from 1 to 100; optionally, wherein each Rw is independently H or methyl. In some embodiments, L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, WSGR Ref. No: 31362-826.601 *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–U–alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–,c –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, WSGR Ref. No: 31362-826.601 –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–; wherein: each U is -NH-AA-C(O)-, wherein each AA is independently an amino acid; each J is independently:
Figure imgf000020_0001
; each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and *, when present, denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). In some embodiments, wherein each U is independently:
Figure imgf000020_0002
. In some embodiments, L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and - N(Rw)-, and combinations thereof; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; optionally, each Rw is independently H or methyl. WSGR Ref. No: 31362-826.601 In some embodiments, L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, WSGR Ref. No: 31362-826.601 *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn– alkylene–; wherein: each J is independently:
Figure imgf000022_0001
; each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). In some embodiments, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn– and *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: WSGR Ref. No: 31362-826.601 each J is independently:
Figure imgf000023_0001
; each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). In some embodiments, each alkylene, when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; and each nn is independently 1, 2 or 3. In some embodiments, L is *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O- alkylene)nn–, wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10, and wherein * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). In some embodiments, L is *–C(O)-O-CH2-O-P(=O)(OH)-O-P(=O)(OH)-(O-CH2CH2)–, wherein * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). In some embodiments, L is *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, wherein i is 0 or 1, and wherein * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). In some embodiments, L is selected from the group consisting of:
Figure imgf000023_0002
WSGR Ref. No: 31362-826.601
Figure imgf000024_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII); and each + denotes connection to W. In some embodiments, each m is independently 1, 2 or 3; each n is independently 1, 2 or 3; each q is independently 1, 2 or 3; each i is 0 or 1; each * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII); and each + denotes connection to W. In some embodiments, i is 1. In some embodiments, the compound is a compound of Formula (VII):
Figure imgf000024_0002
; or a pharmaceutically acceptable salt thereof. In some embodiments, the compound has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000025_0001
or a pharmaceutically acceptable salt thereof. In some embodiments, the compound is a compound of Formula (VIII):
Figure imgf000025_0002
; or a pharmaceutically acceptable salt thereof. In some embodiments, the compound has the following structure:
Figure imgf000025_0003
or a pharmaceutically acceptable salt thereof. In some general aspects, the present disclosure provides a pharmaceutical composition comprising an ADC of the present disclosure or a compound of the present disclosure, and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. In some embodiments, the pharmaceutical composition further comprises a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid, or combination thereof. WSGR Ref. No: 31362-826.601 In some other general aspects, the present disclosure provides a method of treating or preventing a disease in a subject, the method comprising administering to the subject an effective amount of an ADC of the present disclosure, a compound of the present disclosure, or a pharmaceutical composition comprising an ADC or a compound of the present disclosure. In some embodiments, the method further comprises administering to the subject a therapeutically effective amount of an additional therapeutic agent. In some embodiment, the additional therapeutic agent is a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid or a combination thereof. In some other general aspects, the present disclosure provides an anti-TROP2 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 1 to 17. In some other general aspects, the present disclosure provides an ADC comprising an anti- TROP2 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 1 to 17. In some other general aspects, the present disclosure provides an anti-CD70 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 18 to 24. In some other general aspects, the present disclosure provides an ADC comprising an anti- CD70 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 18 to 24. In some other general aspects, the present disclosure provides an anti-HER2 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 25 to 28. In some other general aspects, the present disclosure provides an ADC comprising an anti- HER2 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 25 to 28. In some other general aspects, the present disclosure provides an anti-PSMA antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 29 to 45. In some other general aspects, the present disclosure provides an ADC comprising an anti- PSMA antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 29 to 45. WSGR Ref. No: 31362-826.601 In some other general aspects, the present disclosure provides an anti-HER3 antibody comprising at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 46 to 58. In some other general aspects, the present disclosure provides an ADC comprising an anti- HER3 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 46 to 58. It is to be understood that the methods and compositions described herein are not limited to the particular methodology, protocols, cell lines, constructs, and reagents described herein and as such may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the methods and compositions described herein. INCOPORATION BY REFERENCE All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. BRIEF DESCRIPTION OF THE DRAWINGS FIG.1 shows evaluation of in vitro cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line HCC1569. FIG.2 shows evaluation of in vitro cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line A375. FIG.3 shows evaluation of in vitro cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line HCC827. FIG. 4 shows evaluation of cytotoxic activity of anti-HER3 ADCs and unconjugated cytotoxins exatecan and Dxd against cell line Calu-6. FIGS. 5A, 5B, 5C and 5D show evaluation of in vitro cytotoxic activity of an anti-TROP2 ADC and unconjugated cytotoxin exatecan against the following cell lines: BxPC-3 (FIG. 5A); MDA-MB-468 (FIG.5B); HCC1806 (FIG.5C); and Calu-6 (FIG.5D). FIG. 6 shows evaluation of in vitro cytotoxicity of an anti-TROP2 ADC and unconjugated cytotoxin exatecan against human keratinocytes. DETAILED DESCRIPTION Before describing the present invention in detail, it is to be understood that this invention is not limited to particular methodologies, or compositions, or biological systems, which can, of course, WSGR Ref. No: 31362-826.601 vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. While various embodiments have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It is to be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby. Definitions Unless otherwise defined herein or below in the remainder of the specification, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs. As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural reference unless the context clearly indicates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the inventions described herein belong. Various methods, materials, and the like, similar or equivalent to those described herein can be used in the practice or testing of the inventions described herein. All publications and patents mentioned herein are incorporated herein by reference in their entirety for the purpose of describing and disclosing, for example, the chemistry, chemical syntheses, compositions and other methodologies that are described in the publications, which might be used in connection with the presently described inventions. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. As used herein, the term “activated ester” or “active ester” refers to an ester functional group that is highly susceptible toward attack by a nucleophile. An activated ester can contain a modification to its precursor (or “unactivated”) ester by modification of the acyl or alkoxy moiety of the precursor ester. In a non-limiting example, the precursor ester is modified by incorporation of an electronegative substituent. Non-limiting examples of activated esters include thioesters and derivatives of nitrophenols or penthafluorophenol, esters derivatized with N-hydroxysuccinimide (NHS), e.g., in the presence of dicyclohexylcarbodiimide (DCC), esters derivatized with hydroxybenzotriazole (HOBt), and the like. As used herein, the term “acyl” refers to a group having the general formula -C(=O)RXI, wherein RXI is independently cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic: WSGR Ref. No: 31362-826.601 cyclic or acyclic, substituted or unsubstituted, branched or unbranched alkyl; cyclic or acyclic, substituted or unsubstituted, branched or unbranched alkenyl; substituted or unsubstituted alkynyl; substituted or unsubstituted aryl; substituted or unsubstituted heteroaryl. Acyl substituents include, but are not limited to, any of the substituents described herein that result in the formation of a stable moiety (e.g., aliphatic, alkyl, alkenyl, alkynyl, heteroaliphatic, heterocyclic, aryl, heteroaryl, - C(O)C1-C6 alkyl, oxo, imino, thiooxo, cyano, isocyano, amino, azido, nitro, hydroxyl, thiol, halogen, aliphaticamino, heteroaliphaticamino, alkylamino, heteroalkylamino, arylamino, heteroarylamino, alkylaryl, arylalkyl, aliphaticoxy, heteroaliphaticoxy, alkyloxy, heteroalkyloxy, aryloxy, heteroaryloxy, aliphatic thioxy, heteroaliphaticthioxy, alkylthioxy, heteroalkylthioxy, arylthioxy, heteroarylthioxy, acyloxy, and the like, each of which may or may not be further substituted). In some embodiments, an acyl is a group has the general formula -C(=O)RXI wherein RXI is substituted C1-C6 alkyl. In some embodiments, an acyl is a group has the general formula -C(=O)RXI wherein RXI is unsubstituted C1-C6 alkyl. In some embodiments, an acyl group as the formula -C(=O)CH3. The terms “alkoxy,” “alkylamino” and “alkylthio” (or thioalkoxy) are used in their conventional sense and refer to those alkyl groups linked to molecules via an oxygen atom, an amino group, or a sulfur atom, respectively. The term “alkyl,” by itself or as part of another molecule means, unless otherwise stated, a straight or branched chain, or cyclic hydrocarbon radical, or combination thereof, which may be fully saturated, mono- or polyunsaturated and can include di- and multivalent radicals, having the number of carbon atoms designated (i.e., C1-C10 means one to ten carbons). Examples of saturated hydrocarbon radicals include, but are not limited to, groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, sec-butyl, cyclohexyl, (cyclohexyl)methyl, cyclopropylmethyl, homologs and isomers of, for example, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like. An unsaturated alkyl group is one having one or more double bonds or triple bonds. Examples of unsaturated alkyl groups include, but are not limited to, vinyl, 2-propenyl, crotyl, 2-isopentenyl, 2-(butadienyl), 2,4- pentadienyl, 3-(1,4-pentadienyl), ethynyl, 1- and 3-propynyl, 3-butynyl, and the higher homologs and isomers. A “lower alkyl” is a shorter chain alkyl group, generally having eight or fewer carbon atoms. Substituents for each of the above noted alkyl groups are selected from the group of acceptable substituents described herein. The term “alkylene” by itself or as part of another molecule means a divalent radical derived from an alkane, as exemplified, by (–CH2–)n, wherein n may be 1 to about 24. By way of example only, such groups include, but are not limited to, groups having 10 or fewer carbon atoms such as the structures –CH2CH2– and –CH2CH2CH2CH2–. The term “alkylene” as used herein includes methylene having the structure –CH2–, unless otherwise noted. The term “alkylene,” unless WSGR Ref. No: 31362-826.601 otherwise noted, is also meant to include those groups described herein as “heteroalkylene.” Substituents for arylene groups are selected from the group of acceptable substituents described herein. The term “alkenylene” by itself or as part of another molecule means a divalent radical derived from an alkene, as exemplified, by (–CH=CH–)n, wherein n may be 1 to about 24. By way of example only, such groups include, but are not limited to, groups having 10 or fewer carbon atoms such as the structures –CH=CH– and –CH=CHCH2CH2–. The term “alkenylene,” unless otherwise noted, is also meant to include those groups described herein as “heteroalkenylene.” The term “alkynylene” by itself or as part of another molecule means a divalent radical derived from an alkyne, as exemplified, by (–C=C–)n, wherein n may be 1 to about 24. By way of example only, such groups include, but are not limited to, groups having 10 or fewer carbon atoms such as the structures –C=C– and –C=CCH2CH2–. The term “alkynylene,” unless otherwise noted, is also meant to include those groups described herein as “heteroalkynylene.” In embodiments are provided novel amino acid sequences. The term “amino acid” refers to naturally occurring and non-natural or unnatural amino acids, as well as amino acid analogs and amino acid mimetics that function in a manner similar to the naturally occurring amino acids. Naturally encoded amino acids are the 20 common amino acids (alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine) and pyrolysine and selenocysteine. Amino acid analogs refer to compounds that have the same basic bound to a hydrogen, a carboxyl group, an amino group, and a functional R group. Such analogs may have modified R groups (by way of example, norleucine) or may have modified peptide backbones while still retaining the same basic chemical structure as a naturally occurring amino acid. Non- limiting examples of amino acid analogs include homoserine, norleucine, methionine sulfoxide, methionine methyl sulfonium. Amino acids may be referred to herein by either their name, their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC- IUB Biochemical Nomenclature Commission. Additionally, nucleotides, may be referred to by their commonly accepted single-letter codes. An “amino or carboxy terminus modification group” refers to any molecule that can be attached to a terminal amine group or terminal carboxy group, respectively. By way of example, such terminal amine groups or terminal carboxy groups may be at the end of polymeric molecules, wherein such polymeric molecules include, but are not limited to, polypeptides, polynucleotides, and polysaccharides. Terminus modification groups include but are not limited to, various water-soluble WSGR Ref. No: 31362-826.601 polymers, peptides or proteins. By way of example only, terminus modification groups include polyethylene glycol or serum albumin. Terminus modification groups may be used to modify therapeutic characteristics of the polymeric molecule, including but not limited to increasing the serum half-life of peptides, polypeptides or proteins. In some embodiments the disclosure provides novel antibodies and antibody variants. The term “antibody” herein refers to a protein consisting of one or more polypeptides substantially encoded by all or part of the antibody genes. The immunoglobulin genes include, but are not limited to, the kappa, lambda, alpha, gamma (IgG1, IgG2, IgG3, and IgG4), delta, epsilon and mu constant region genes, as well as the myriad immunoglobulin variable region genes. Antibody herein is also meant to include full-length antibodies and antibody fragments, and include antibodies that exist naturally in any organism, antibody variants, engineered antibodies and antibody fragments. Antibody herein is also meant to include intact antibody, monoclonal or polyclonal antibodies. Antibody herein also encompasses, multispecific antibodies and/or bispecific antibodies. Antibodies of the present disclosure include human antibodies. Human antibodies are usually made of two light chains and two heavy chains each comprising variable regions and constant regions. The light chain variable region comprises 3 CDRs, identified herein as CDRL1, CDRL2 and CDRL3 flanked by framework regions. The heavy chain variable region comprises 3 CDRs, identified herein as CDRH1, CDRH2 and CDRH3 flanked by framework regions. The term “antibody fragment” herein refers to any form of an antibody other than the full- length form. Antibody fragments herein include antibodies that are smaller components that exist within full-length antibodies, and antibodies that have been engineered, such as antibody variants. Antibody fragments include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, and variable regions, and alternative scaffold non-antibody molecules, bispecific antibodies, and the like (Maynard & Georgiou, Annu. Rev. Biomed. Eng.2:339-76, 2000; Hudson, Curr. Opin. Biotechnol.9:395-402, 1998). Another functional substructure is a single chain Fv (scFv), comprised of the variable regions of the immunoglobulin heavy and light chain, covalently connected by a peptide linker (Hu et al., Cancer Research, 56, 3055-3061, 1996). These small (Mr 25,000) proteins generally retain specificity and affinity for antigen in a single polypeptide and can provide a convenient building block for larger, antigen-specific molecules. Unless specifically noted otherwise, statements and claims that use the term “antibody” or “antibodies” specifically includes “antibody fragment” and “antibody fragments.” WSGR Ref. No: 31362-826.601 In some embodiments, novel antibody drug conjugates (ADCs) are disclosed. The term “antibody-drug conjugate, or “ADC”, as used herein, refers to an antibody molecule, or fragment thereof, that is covalently bonded to one or more biologically active molecule(s). The biologically active molecule may be conjugated to the antibody through a linker, polymer, or other covalent bond. ADCs are a potent class of therapeutic constructs that allow targeted delivery of cytotoxic agents to target cells, such as cancer cells. Because of the targeting function, these compounds show a much higher therapeutic index compared to the same systemically delivered agents. ADCs have been developed as intact antibodies or antibody fragments, such as scFvs. The antibody or fragment is linked to one or more copies of drug via a linker that is stable under physiological conditions, but that may be cleaved once inside the target cell. The term "antigen-binding fragment", as used herein, refers to one or more fragments of an antibody that retain the ability to bind to an antigen. It has been shown that the antigen-binding function of an antibody can be performed by fragments of an intact antibody. Examples of binding fragments encompassed within the term "antigen-binding fragment" of an antibody include (i) a Fab fragment, a monovalent fragment consisting of the VL, VH, CL and CH1 domains; (ii) a F(ab')2 fragment, a bivalent fragment comprising two Fab fragments linked by a disulfide bridge at the hinge region; (iii) a Fd fragment consisting of the VH and CH1 domains; (iv) a Fv fragment consisting of the VL and VH domains of a single arm of an antibody, (v) a dAb fragment (Ward et al., Nature 341:544- 546, 1989), which consists of a VH domain; (vi) an isolated complementarity determining region (CDR), e.g., VH CDR3 comprising or not additional sequence (linker, framework region(s) etc.) and (v) a combination of two to six isolated CDRs comprising or not additional sequence (linker, framework region(s) etc.). Furthermore, although the two domains of the Fv fragment, VL and VH, are coded for by separate genes, they can be joined, using recombinant methods, by a synthetic linker that enables them to be made as a single polypeptide chain in which the VL and VH regions pair to form monovalent molecules (known as single chain Fv (scFv); see e.g., Bird et al., Science 242:423- 426, 1988); and (Huston et al., Proc. Natl. Acad. Sci. USA 85:5879-5883, 1988). Such single chain antibodies are also intended to be encompassed within the term "antigen-binding fragment" of an antibody. Furthermore, the antigen-binding fragments include binding-domain immunoglobulin fusion proteins comprising (i) a binding domain polypeptide (such as a heavy chain variable region, a light chain variable region, or a heavy chain variable region fused to a light chain variable region via a linker peptide) that is fused to an immunoglobulin hinge region polypeptide, (ii) an immunoglobulin heavy chain CH2 constant region fused to the hinge region, and (iii) an immunoglobulin heavy chain CH3 constant region fused to the CH2 constant region. The hinge region may be modified by replacing one or more cysteine residues with serine residues to prevent WSGR Ref. No: 31362-826.601 dimerization. Such binding-domain immunoglobulin fusion proteins are further disclosed in US 2003/0118592 and US 2003/0133939. These antibody fragments are obtained using conventional techniques known to those with skill in the art, and the fragments are screened for utility in the same manner as are intact antibodies. A typical antigen binding site is comprised of the variable regions formed by the pairing of a light chain immunoglobulin and a heavy chain immunoglobulin. The structure of the antibody variable regions is very consistent and exhibits very similar structures. These variable regions are typically comprised of relatively homologous framework regions (FR) interspaced with three hypervariable regions termed Complementarity Determining Regions (CDRs). The overall binding activity of the antigen binding fragment is often dictated by the sequence of the CDRs. The FRs often play a role in the proper positioning and alignment in three dimensions of the CDRs for optimal antigen binding. In fact, because CDR sequences are responsible for most antibody-antigen interactions, it is possible to express recombinant antibodies that shows the properties of specific naturally occurring antibodies by constructing expression vectors that include CDR sequences from the specific naturally occurring antibody grafted onto framework sequences from a different antibody with different properties (see, e.g., Riechmann, L. et al., Nature 332:323-327, 1998; Jones, P. et al., Nature 321:522-525, 1986; and Queen, C. et al., Proc. Natl. Acad. USA 86:10029-10033, 1989). Such framework sequences can be obtained from public DNA databases that include germline antibody gene sequences. These germline sequences will differ from mature antibody gene sequences because they will not include completely assembled variable genes, which are formed by V(D)J joining during B cell maturation. Germline gene sequences will also differ from the sequences of a high affinity secondary repertoire antibody which contains mutations throughout the variable gene but typically clustered in the CDRs. For example, somatic mutations are relatively infrequent in the amino terminal portion of framework region 1 and in the carboxy-terminal portion of framework region 4. Furthermore, many somatic mutations do not significantly alter the binding properties of the antibody. For this reason, it is not necessary to obtain the entire DNA sequence of a particular antibody in order to recreate an intact recombinant antibody having binding properties similar to those of the original antibody. Partial heavy and light chain sequence spanning the CDR regions is typically sufficient for this purpose. The partial sequence is used to determine which germline variable and joining gene segments contributed to the recombined antibody variable genes. The germline sequence is then used to fill in missing portions of the variable regions. Heavy and light chain leader sequences are cleaved during protein maturation and do not contribute to the properties of the final antibody. To add missing sequences, cloned cDNA sequences can be combined with synthetic oligonucleotides by ligation or PCR amplification. Alternatively, the entire variable region WSGR Ref. No: 31362-826.601 can be synthesized to create an entirely synthetic variable region clone. This process has certain advantages such as elimination or inclusion of particular restriction sites, or optimization of particular codons. Of course, the totality or portions of the framework region of the antibody described herein may be used in conjunction with the CDRs in order to optimize the affinity, specificity or any other desired properties of the antibody. The term “aromatic” or “aryl”, as used herein, refers to a closed ring structure which has at least one ring having a conjugated pi electron system and includes both carbocyclic aryl and heterocyclic aryl (or “heteroaryl” or “heteroaromatic”) groups. The carbocyclic or heterocyclic aromatic group may contain from 5 to 20 ring atoms. The term includes monocyclic rings linked covalently or fused-ring polycyclic (i.e., rings which share adjacent pairs of carbon atoms) groups. An aromatic group can be unsubstituted or substituted. Non-limiting examples of “aromatic” or “aryl”, groups include phenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, anthracenyl, and phenanthracenyl. Non-limiting examples of “heteroaryl” groups are described herein. Substituents for each of the above noted aryl and heteroaryl ring systems are selected from the group of acceptable substituents described herein. For brevity, the term “aromatic” or “aryl” when used in combination with other terms (including but not limited to, aryloxy, arylthioxy, aralkyl) includes both aryl and heteroaryl rings as defined above. Thus, the term “aralkyl” or “alkaryl” is meant to include those radicals in which an aryl group is attached to an alkyl group (including but not limited to, benzyl, phenethyl, pyridylmethyl and the like) including those alkyl groups in which a carbon atom (including but not limited to, a methylene group) has been replaced by a heteroatom, by way of example only, by an oxygen atom. Examples of such aryl groups include, but are not limited to, phenoxymethyl, 2- pyridyloxymethyl, 3-(1-naphthyloxy)propyl, and the like. The term “arylene”, as used herein, refers to a divalent aryl radical. Non-limiting examples of “arylene” include phenylene, pyridinylene, pyrimidinylene and thiophenylene. Substituents for arylene groups are selected from the group of acceptable substituents described herein. In some embodiments the disclosure concerns polymers such as a bifunctional polymer. A “bifunctional polymer”, also referred to as a “bifunctional linker”, refers to a polymer comprising two functional groups that are capable of reacting specifically with other moieties to form covalent or non-covalent linkages. Such moieties may include, but are not limited to, the side groups on natural or non-natural amino acids or peptides which contain such natural or non-natural amino acids. The other moieties that may be linked to the bifunctional linker or bifunctional polymer may be the same or different moieties. By way of example only, a bifunctional linker may have a functional group reactive with a group on a first peptide, and another functional group which is reactive with a group WSGR Ref. No: 31362-826.601 on a second peptide, whereby forming a conjugate that includes the first peptide, the bifunctional linker and the second peptide. Many procedures and linker molecules for attachment of various compounds to peptides are known. See, for example, European Patent Application No. 0188256; U.S. Patent Nos.4,659,839; 4,414,148; 4,699,784; 4,680,338; and 4,569,789 incorporated herein by reference in their entirety. A “multi-functional polymer” also referred to as a “multi-functional linker”, refers to a polymer comprising two or more functional groups that are capable of reacting with other moieties. Such moieties may include, but are not limited to, the side groups on natural or non-natural amino acids or peptides which contain such natural or non-natural amino acids (including but not limited to, amino acid side groups) to form covalent or non-covalent linkages. A bi-functional polymer or multi-functional polymer may be any desired length or molecular weight and may be selected to provide a particular desired spacing or conformation between one or more molecules linked to a compound and molecules it binds to, or to the compound. The term “bioavailability,” as used herein, refers to the rate and extent to which a substance or its active moiety is delivered from a pharmaceutical dosage form and becomes available at the site of action or in the general circulation. Increases in bioavailability refers to increasing the rate and extent a substance or its active moiety is delivered from a pharmaceutical dosage form and becomes available at the site of action or in the general circulation. By way of example, an increase in bioavailability may be indicated as an increase in concentration of the substance or its active moiety in the blood when compared to other substances or active moieties. The term “biologically active molecule”, “biologically active moiety” or “biologically active agent” when used herein means any substance which can affect any physical or biochemical properties of a biological system, pathway, molecule, or interaction relating to an organism, including but not limited to, viruses, bacteria, bacteriophage, transposon, prion, insects, fungi, plants, animals, and humans. In particular, as used herein, biologically active molecules include but are not limited to any substance intended for diagnosis, cure, mitigation, treatment, or prevention of disease in humans or other animals, or to otherwise enhance physical or mental well-being of humans or animals. Examples of biologically active molecules include, but are not limited to, peptides, proteins, enzymes, small molecule drugs, hard drugs, soft drugs, prodrugs, carbohydrates, inorganic atoms or molecules, dyes, lipids, nucleosides, radionuclides, oligonucleotides, toxins, cells, viruses, liposomes, microparticles and micelles. Classes of biologically active agents that are suitable for use with the methods and compositions described herein include, but are not limited to, drugs, prodrugs, radionuclides, imaging agents, polymers, antibiotics, fungicides, anti-viral agents, anti-inflammatory agents, anti-tumor agents, cardiovascular agents, anti-anxiety agents, hormones, growth factors, steroidal and nonsteroidal agents, microbially derived toxins, and the like. WSGR Ref. No: 31362-826.601 By “modulating biological activity” is meant increasing or decreasing the reactivity of a polypeptide, altering the selectivity of the polypeptide, enhancing or decreasing the substrate selectivity of the polypeptide. Analysis of modified biological activity can be performed by comparing the biological activity of the non-natural polypeptide to that of the natural polypeptide. In some embodiments the disclosure concerns amino acids that have been biosynthetically incorporated in the antibody. The term “biosynthetically,” as used herein, refers to any method utilizing a translation system (cellular or non-cellular), including use of at least one of the following components: a polynucleotide, a codon, a tRNA, and a ribosome. By way of example, non-natural amino acids may be “biosynthetically incorporated” into non-natural amino acid polypeptides using the methods and techniques described herein and as is well known in the art. See for example, WO2010/011735 and WO2005/074650. The term “carbonyl” as used herein refers to the moiety -C(O)-. Groups containing a carbonyl include but are not limited to a ketone, an aldehyde, an ester, a carboxylic acid, a thioester and an amide. In addition, such groups may be part of linear, branched, or cyclic molecules. The term “chemically cleavable group,” also referred to as “chemically labile”, as used herein, refers to a group which breaks or cleaves upon exposure to acid, base, oxidizing agents, reducing agents, chemical initiators or radical initiators. The term “chromophore,” as used herein, refers to a molecule which absorbs light of visible wavelengths, UV wavelengths or IR wavelengths. A “comparison window,” as used herein, refers a segment of any one of contiguous positions used to compare a sequence to a reference sequence of the same number of contiguous positions after the two sequences are optimally aligned. Such contiguous positions include, but are not limited to a group consisting of from about 20 to about 600 sequential units, including about 50 to about 200 sequential units, and about 100 to about 150 sequential units. By way of example only, such sequences include polypeptides and polypeptides containing non-natural amino acids, with the sequential units include, but are not limited to natural and non-natural amino acids. In addition, by way of example only, such sequences include polynucleotides with nucleotides being the corresponding sequential units. Methods of alignment of sequences for comparison are well-known in the art. Optimal alignment of sequences for comparison can be conducted, including but not limited to, by the local homology algorithm of Smith and Waterman (1970) Adv. Appl. Math.2:482c, by the homology alignment algorithm of Needleman and Wunsch (1970) J. Mol. Biol.48:443, by the search for similarity method of Pearson and Lipman (1988) Proc. Nat’l. Acad. Sci. USA 85:2444, by computerized implementations of these algorithms (GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Dr., Madison, WI), WSGR Ref. No: 31362-826.601 or by manual alignment and visual inspection (see, e.g., Ausubel et al., Current Protocols in Molecular Biology (1995 supplement)). By way of example, an algorithm which may be used to determine percent sequence identity and sequence similarity are the BLAST and BLAST 2.0 algorithms, which are described in Altschul et al. (1997) Nuc. Acids Res. 25:3389-3402, and Altschul et al. (1990) J. Mol. Biol. 215:403-410, respectively. Software for performing BLAST analyses is publicly available through the National Center for Biotechnology Information. The BLAST algorithm parameters W, T, and X determine the sensitivity and speed of the alignment. The BLASTN program (for nucleotide sequences) uses as defaults a wordlength (W) of 11, an expectation (E) or 10, M=5, N=-4 and a comparison of both strands. For amino acid sequences, the BLASTP program uses as defaults a wordlength of 3, and expectation (E) of 10, and the BLOSUM62 scoring matrix (see Henikoff and Henikoff (1992) Proc. Natl. Acad. Sci. USA 89:10915) alignments (B) of 50, expectation (E) of 10, M=5, N=-4, and a comparison of both strands. The BLAST algorithm is typically performed with the “low complexity” filter turned off. The BLAST algorithm also performs a statistical analysis of the similarity between two sequences (see, e.g., Karlin and Altschul (1993) Proc. Natl. Acad. Sci. USA 90:5873-5787). One measure of similarity provided by the BLAST algorithm is the smallest sum probability (P(N)), which provides an indication of the probability by which a match between two nucleotide or amino acid sequences would occur by chance. For example, a nucleic acid is considered similar to a reference sequence if the smallest sum probability in a comparison of the test nucleic acid to the reference nucleic acid is less than about 0.2, or less than about 0.01, or less than about 0.001. The term “conservatively modified variants” applies to both natural and non-natural amino acid and natural and non-natural nucleic acid sequences, and combinations thereof. With respect to particular nucleic acid sequences, “conservatively modified variants” refers to those natural and non- natural nucleic acids which encode identical or essentially identical natural and non-natural amino acid sequences, or where the natural and non-natural nucleic acid does not encode a natural and non- natural amino acid sequence, to essentially identical sequences. By way of example, because of the degeneracy of the genetic code, a large number of functionally identical nucleic acids encode any given protein. For instance, the codons GCA, GCC, GCG and GCU all encode the amino acid alanine. Thus, at every position where an alanine is specified by a codon, the codon can be altered to any of the corresponding codons described without altering the encoded polypeptide. Such nucleic acid variations are “silent variations,” which are one species of conservatively modified variations. Thus, by way of example every natural or non-natural nucleic acid sequence herein which encodes a natural or non-natural polypeptide also describes every possible silent variation of the natural or non-natural WSGR Ref. No: 31362-826.601 nucleic acid. One of ordinary skill in the art will recognize that each codon in a natural or non-natural nucleic acid (except AUG, which is ordinarily the only codon for methionine, and TGG, which is ordinarily the only codon for tryptophan) can be modified to yield a functionally identical molecule. Accordingly, each silent variation of a natural and non-natural nucleic acid which encodes a natural and non-natural polypeptide is implicit in each described sequence. As to amino acid sequences, individual substitutions, deletions or additions to a nucleic acid, peptide, polypeptide, or protein sequence which alters, adds or deletes a single natural and non-natural amino acid or a small percentage of natural and non-natural amino acids in the encoded sequence is a “conservatively modified variant” where the alteration results in the deletion of an amino acid, addition of an amino acid, or substitution of a natural and non-natural amino acid with a chemically similar amino acid. Conservative substitution tables providing functionally similar natural amino acids are well known in the art. Conservative substitution tables providing functionally similar amino acids are known to those of ordinary skill in the art. The following eight groups each contain amino acids that are conservative substitutions for one another: 1) Alanine (A), Glycine (G); 2) Aspartic acid (D), Glutamic acid (E); 3) Asparagine (N), Glutamine (Q); 4) Arginine (R), Lysine (K); 5) Isoleucine (I), Leucine (L), Methionine (M), Valine (V); 6) Phenylalanine (F), Tyrosine (Y), Tryptophan (W); 7) Serine (S), Threonine (T); and 8) Cysteine (C), Methionine (M) (see, e.g., Creighton, Proteins: Structures and Molecular Properties (W H Freeman & Co.; 2nd edition, 1993). Such conservatively modified variants are in addition to and do not exclude polymorphic variants, interspecies homologs, and alleles of the compositions described herein. The terms “cycloalkyl” and “heterocycloalkyl”, by themselves or in combination with other terms, represent, unless otherwise stated, cyclic versions of “alkyl” and “heteroalkyl”, respectively. Thus, a cycloalkyl or heterocycloalkyl includes saturated, partially unsaturated and fully unsaturated ring linkages. Additionally, for heterocycloalkyl, a heteroatom can occupy the position at which the heterocycle is attached to the remainder of the molecule. The heteroatom may include, but is not limited to, oxygen, nitrogen or sulfur. The carbocycloalkyl or heterocycloalkyl group can contain from 3 to 20 ring atoms. Examples of cycloalkyl include, but are not limited to, cyclopentyl, cyclohexyl, 1-cyclohexenyl, 3-cyclohexenyl, cycloheptyl, cyclooctynyl, and the like. Examples of heterocycloalkyl include, but are not limited to, 1–(1,2,5,6-tetrahydropyridyl), 1-piperidinyl, 2- piperidinyl, 3-piperidinyl, 4-morpholinyl, 3-morpholinyl, tetrahydrofuran-2-yl, tetrahydrofuran-3-yl, tetrahydrothien-2-yl, tetrahydrothien-3-yl, 1–piperazinyl, 2-piperazinyl, and the like. Additionally, the term encompasses multicyclic structures, including but not limited to, bicyclic and tricyclic ring structures. Similarly, the term “heterocycloalkylene” by itself or as part of another molecule means a divalent radical derived from heterocycloalkyl, and the term “cycloalkylene” by itself or as part of WSGR Ref. No: 31362-826.601 another molecule means a divalent radical derived from cycloalkyl. Substituents for each of the above noted cycloalkyl and heterocycloalkyl ring systems are selected from the group of acceptable substituents described herein. The term “cyclodextrin,” as used herein, refers to cyclic carbohydrates consisting of at least six to eight glucose molecules in a ring formation. The outer part of the ring contains water soluble groups; at the center of the ring is a relatively nonpolar cavity able to accommodate small molecules. The term “diamine” as used herein, refers to groups/molecules comprising at least two amine functional groups, including, but not limited to, a hydrazine group, an amidine group, an imine group, a 1,1-diamine group, a 1,2-diamine group, a 1,3-diamine group, and a 1,4-diamine group. In addition, such groups may be part of linear, branched, or cyclic molecules. The term “detectable label,” as used herein, refers to a label which may be observable using analytical techniques including, but not limited to, fluorescence, chemiluminescence, electron-spin resonance, ultraviolet/visible absorbance spectroscopy, mass spectrometry, nuclear magnetic resonance, magnetic resonance, and electrochemical methods. The term “dicarbonyl” as used herein refers to a group containing at least two moieties selected from the group consisting of -C(O)-, -S(O)-, -S(O)2-, and –C(S)-, including, but not limited to, 1,2-dicarbonyl groups, a 1,3-dicarbonyl groups, and 1,4-dicarbonyl groups, and groups containing a least one ketone group, and/or at least one aldehyde groups, and/or at least one ester group, and/or at least one carboxylic acid group, and/or at least one thioester group. Such dicarbonyl groups include diketones, ketoaldehydes, ketoacids, ketoesters, and ketothioesters. In addition, such groups may be part of linear, branched, or cyclic molecules. The two moieties in the dicarbonyl group may be the same or different, and may include substituents that would produce, by way of example only, an ester, a ketone, an aldehyde, a thioester, or an amide, at either of the two moieties. The term “drug,” as used herein, refers to any substance used in the prevention, diagnosis, alleviation, treatment, or cure of a disease or condition such as cancer, including but not limited to oral, colorectal, gastric, esophageal, hepatocellular, non-small-cell-lung (NSCL), small-cell lung (SCL), ovarian, breast including triple-negative breast, prostate, pancreatic, head and neck, squamous, renal, bladder, cervical, endometrial, thyroid, glioblastoma cancer. The term “drug-to-antibody ratio” (“DAR”) as used herein refers to the average (mean) number of drugs that are conjugated to an antibody in an antibody-drug conjugate (ADC) composition. The DAR value reflects the homogeneity of the ADC population in the composition, and also indicates the amount of “payload” (e.g., drug or drug-linker) that is loaded onto an antibody and can be delivered to a target (e.g., cell or diseased tissue). DAR can be determined by methods known to a person of ordinary skill in the art, for example, LC-MS (e.g., see Tang, Y. et al., Real- WSGR Ref. No: 31362-826.601 Time Analysis on Drug-Antibody Ratio of Antibody-Drug Conjugates for Synthesis, Process Optimization and Quality Control, Sci Rep 7, 7763 (2017). doi: 10.1038/s41598-017-08151-2; and Chen, Y. Drug-to-antibody ratio (DAR) by UV/Vis spectroscopy, Methods Mol. Biol., 2013;1045:267-73. doi: 10.1007/978-1-62703-541-5_16). In a non-limiting example, an ADC can have a population distribution of 20% of drug-loaded antibody, wherein the drug load is two (2) drugs per antibody; 25% of drug-loaded antibody, wherein the drug load is three (3) drugs per antibody; and 55% of drug-loaded antibody, wherein the drug load is four (4) drugs per antibody; thus, in this example, DAR is [(0.2 x 2) + (0.25 x 3) + (0.55 x 4)] = 3.35. The term “dye” as used herein, refers to a soluble, coloring substance which contains a chromophore. The term “effective amount,” as used herein, refers to a sufficient amount of an agent, compound or composition being administered which will relieve to some extent one or more of the symptoms of the disease or condition being treated. The result can be reduction and/or alleviation of the signs, symptoms, or causes of a disease, or any other desired alteration of a biological system. By way of example, an agent, compound or composition being administered includes, but is not limited to, a natural amino acid polypeptide, non-natural amino acid polypeptide, modified natural amino acid polypeptide, modified non-amino acid polypeptide, or an antibody or variant thereof. Compositions containing such natural amino acid polypeptides, non-natural amino acid polypeptides, modified natural amino acid polypeptides, modified non-natural amino acid polypeptides, or an antibody or variant thereof can be administered for prophylactic, enhancing, and/or therapeutic treatments. An appropriate “effective” amount in any individual case may be determined using techniques, such as a dose escalation study. The terms “enhance” or “enhancing” means to increase or prolong either in potency or duration a desired effect. By way of example, “enhancing” the effect of therapeutic agents refers to the ability to increase or prolong, either in potency or duration, the effect of therapeutic agents on during treatment of a disease, disorder or condition. An “enhancing-effective amount,” as used herein, refers to an amount adequate to enhance the effect of a therapeutic agent in the treatment of a disease, disorder or condition. When used in a patient, amounts effective for this use will depend on the severity and course of the disease, disorder or condition, previous therapy, the patient's health status and response to the drugs, and the judgment of the treating physician. As used herein, the term “eukaryote” refers to organisms belonging to the phylogenetic domain Eucarya, including but not limited to animals (including but not limited to, mammals, insects, reptiles, birds, etc.), ciliates, plants (including but not limited to, monocots, dicots, and algae), fungi, yeasts, flagellates, microsporidia, and protists. WSGR Ref. No: 31362-826.601 The terms “functional group”, “active moiety”, “activating group”, “leaving group”, “reactive site”, “chemically reactive group” and “chemically reactive moiety,” as used herein, refer to portions or units of a molecule at which chemical reactions occur. The terms are somewhat synonymous in the chemical arts and are used herein to indicate the portions of molecules that perform some function or activity and are reactive with other molecules. The term “haloacyl,” as used herein, refers to acyl groups which contain halogen moieties, including, but not limited to, -C(O)CH2F, -C(O)CF3, -C(O)CH2OCCl3, and the like. The term “haloalkyl,” as used herein, refers to alkyl groups which contain halogen moieties, including, but not limited to, -CF3 and –CH2CF3 and the like. The term “halogen” as used herein includes fluorine, chlorine, bromine and iodine. In some embodiments, “halogen” may be referred to as “halo.” Non-limiting examples of halogen substituents include -F, -Cl, -Br and -I. Non-limiting examples of halogen ions include fluoride, chloride, bromide and iodide. The term “heavy atom,” as used herein, refers to a group which incorporates an ion or atom which is usually heavier than carbon. Such ions or atoms include, but are not limited to, silicon, tungsten, gold, lead, and uranium. The term “heteroalkyl,” as used herein, refers to straight or branched chain, or cyclic hydrocarbon radicals, or combinations thereof, consisting of an alkyl group and at least one heteroatom selected from the group consisting of O, N, Si and S, and wherein the nitrogen and sulfur atoms may optionally be oxidized and the nitrogen heteroatom may optionally be quaternized. The heteroatom(s) O, N and S and Si may be placed at any interior position of the heteroalkyl group or at the position at which the alkyl group is attached to the remainder of the molecule. Examples include, but are not limited to, -CH2-CH2-O-CH3, -CH2-CH2-NH-CH3, -CH2-CH2-N(CH3)-CH3, -CH2-S-CH2- CH3, -CH2-CH2,-S(O)-CH3, -CH2-CH2-S(O)2-CH3, -CH=CH-O-CH3, -Si(CH3)3, -CH2-CH=N-OCH3, and –CH=CH-N(CH3)-CH3. In addition, up to two heteroatoms may be consecutive, such as, by way of example, -CH2-NH-OCH3 and –CH2-O-Si(CH3)3. Substituents for each of the above noted heteroalkyl groups are selected from the group of acceptable substituents described herein. The terms “heterocyclic-based linkage” or “heterocycle linkage” refers to a moiety formed from the reaction of a dicarbonyl group with a diamine group. The resulting reaction product is a heterocycle, including a heteroaryl group or a heterocycloalkyl group. The resulting heterocycle group serves as a chemical link between a non-natural amino acid or non-natural amino acid polypeptide and another functional group. In one embodiment, the heterocycle linkage includes a nitrogen-containing heterocycle linkage, including by way of example only a pyrazole linkage, a pyrrole linkage, an indole linkage, a benzodiazepine linkage, and a pyrazalone linkage. WSGR Ref. No: 31362-826.601 Similarly, the term “heteroalkylene” refers to a divalent radical derived from heteroalkyl, as exemplified, but not limited by, -CH2-CH2-S-CH2-CH2- and –CH2-S-CH2-CH2-NH-CH2-. For heteroalkylene groups, the same or different heteroatoms can also occupy either or both of the chain termini (including but not limited to, alkyleneoxy, alkylenedioxy, alkyleneamino, alkylenediamino, aminooxyalkylene, and the like). Still further, for alkylene and heteroalkylene linking groups, no orientation of the linking group is implied by the direction in which the formula of the linking group is written. By way of example, the formula –C(O)2R’- represents both –C(O)2R’- and –R’C(O)2-. The term "heteroaryl" or "heteroaromatic," as used herein, refers to aryl groups which contain at least one heteroatom selected from the group consisting of N, O and S; wherein the nitrogen and sulfur atoms are optionally oxidized, and the nitrogen atom(s) are optionally quaternized. The heteroaryl group may contain from 5 to 20 ring atoms. The term includes monocyclic rings linked covalently or fused-ring polycyclic (i.e., rings which share adjacent pairs of atoms) groups. Heteroaryl groups may be substituted or unsubstituted. A heteroaryl group may be attached to the remainder of the molecule through a ring heteroatom or a ring carbon atom. Non-limiting examples of heteroaryl groups include benzimidazolyl, benzothiazolyl, furanyl, imidazolyl, indolizinyl, indolyl, isoquinolyl, isothiazolyl, isoxazolyl, naphthyridinyl, oxadiazolyl, oxazolyl, pteridinyl, purinyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, quinolyl, quinoxalinyl, tetrazolyl, thiadiazolyl, thienyl, thiazolyl and triazolyl. Additional and more particular non-limiting examples of heteroaryl groups include 2-benzimidazolyl, 4-benzimidazolyl, 5-benzimidazolyl, 6- benzimidazolyl, 7-benzimidazolyl, 2-benzothiazolyl, 4-benzothiazolyl, 5-benzothiazolyl, 6- benzothiazolyl, 7-benzothiazolyl, 2-furanyl, 3-furanyl, 1-imidazolyl, 2-imidazolyl, 3-imidazolyl, 4- imidazolyl, 5-imidazolyl, 1-indolizinyl, 2-indolizinyl, 3-indolizinyl, 5-indolizinyl, 6-indolizinyl, 7- indolizinyl, 8-indolizinyl, 2-indolyl, 3-indolyl, 4-indolyl, 5-indolyl, 6-indolyl, 7-indolyl, 1- isoquinolyl, 3-isoquinolyl, 4-isoquinolyl, 5-isoquinolyl, 6-isoquinolyl, 7-isoquinolyl, 8-isoquinolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 1,8- naphthyridinyl, 4-oxadiazolyl, 5-oxadiazolyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 2-pteridinyl, 4- pteridinyl, 6-pteridinyl, 7-pteridinyl, 2-purinyl, 6-purinyl, 7-purinyl, 8-purinyl, 2-pyrazinyl, 1- pyrazolyl, 2-pyrazolyl, 3-pyrazolyl, 4-pyrazolyl, 5-pyrazolyl, 3-pyridazinyl, 4-pyridazinyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5- pyrimidinyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-quinolyl, 3-quinolyl, 4-quinolyl, 5-quinolyl, 6-quinolyl, 7-quinolyl, 8-quinolyl, 2-quinoxalinyl, 5- quinoxalinyl, 6-quinoxalinyl, 1-tetrazolyl, 5-tetrazolyl, 4-thiadiazolyl, 5-thiadiazolyl, 2-thienyl, 3- thienyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 1-triazolyl, 2-triazolyl, 3-triazolyl, 4-triazolyl and 5- triazolyl. Substituents for each of the above noted heteroaryl ring systems are selected from the group of acceptable substituents described herein. WSGR Ref. No: 31362-826.601 The term "humanized or chimeric antibody" refer to a molecule, generally prepared using recombinant techniques, having an antigen binding site derived from an immunoglobulin from a non- human species, (e.g., murine), and the remaining immunoglobulin structure of the molecule based upon the structure and/or sequence of a human immunoglobulin. In general, the humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the hypervariable loops correspond to those of a non-human immunoglobulin and all or substantially all of the framework residues/regions (FR) are those of a human immunoglobulin sequence. The humanized antibody optionally also will comprise at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin. The humanized forms of rodent antibodies will essentially comprise the same CDR sequences of the parental rodent antibodies, although certain amino acid substitutions may be included to increase affinity, increase stability of the humanized antibody, or for other reasons. However, as CDR loop exchanges do not uniformly result in an antibody with the same binding properties as the antibody of origin, changes in framework residues (FR), residues involved in CDR loop support, might also be introduced in humanized antibodies to preserve antigen binding affinity. The antigen-binding site may comprise either complete variable domains fused onto constant domains or only the complementarity determining regions (CDRs) grafted onto appropriate framework regions in the variable domains. Antigen binding sites may be wild type or modified by one or more amino acid substitutions. This eliminates the constant region as an immunogen in human individuals, but the possibility of an immune response to the foreign variable region remains (LoBuglio, A. F. et al., "Mouse/Human Chimeric Monoclonal Antibody in Man: Kinetics and Immune Response," Proc. Natl. Acad. Sci. (USA) 86:4220-4224, 1989). Another approach focuses not only on providing human-derived constant regions but modifying the variable regions as well so as to reshape them as closely as possible to human form. It is known that the variable regions of both heavy and light chains contain three complementarity-determining regions (CDRs) which vary in response to the antigens in question and determine binding capability, flanked by four framework regions (FRs) which are relatively conserved in a given species and which putatively provide a scaffolding for the CDRs. When nonhuman antibodies are prepared with respect to a particular antigen, the variable regions can be "humanized" by grafting CDRs derived from nonhuman antibody on the FRs present in the human antibody to be modified. Application of this approach to various antibodies has been reported by Kettleborough, C. A. et al., "Humanization Of A Mouse Monoclonal Antibody By CDR-Grafting: The Importance Of Framework Residues On Loop Conformation," Protein Engineering 4:773- 3783,1991; Co, M. S. et al., "Humanized Antibodies For Antiviral Therapy," Proc. Natl. Acad. Sci. (USA) 88:2869-2873,1991; Carter, P. et al., "Humanization Of An Anti-p185her2 Antibody For WSGR Ref. No: 31362-826.601 Human Cancer Therapy," Proc. Natl. Acad. Sci. (USA) 89:4285-4289,1992; and Co, M. S. et al., "Chimeric And Humanized Antibodies With Specificity For The CD33 Antigen," J. Immunol. 148:1149-1154,1992. In some embodiments, humanized antibodies preserve all CDR sequences (for example, a humanized mouse antibody which contains all six CDRs from the mouse antibodies). In other embodiments, humanized antibodies have one or more CDRs (one, two, three, four, five, six) which are altered with respect to the original antibody, which are also termed one or more CDRs "derived from" one or more CDRs from the original antibody. The term “identical,” as used herein, refers to two or more sequences or subsequences which are the same. In addition, the term “substantially identical,” as used herein, refers to two or more sequences which have a percentage of sequential units which are the same when compared and aligned for maximum correspondence over a comparison window, or designated region as measured using comparison algorithms or by manual alignment and visual inspection. By way of example only, two or more sequences may be “substantially identical” if the sequential units are about 60% identical, about 65% identical, about 70% identical, about 75% identical, about 80% identical, about 85% identical, about 90% identical, or about 95% identical over a specified region. Such percentages describe the “percent identity” of two or more sequences. The identity of a sequence can exist over a region that is at least about 75-100 sequential units in length, over a region that is about 50 sequential units in length, or, where not specified, across the entire sequence. This definition also refers to the complement of a test sequence. By way of example only, two or more polypeptide sequences are identical when the amino acid residues are the same, while two or more polypeptide sequences are “substantially identical” if the amino acid residues are about 60% identical, about 65% identical, about 70% identical, about 75% identical, about 80% identical, about 85% identical, about 90% identical, or about 95% identical over a specified region. The identity can exist over a region that is at least about 75 to about 100 amino acids in length, over a region that is about 50 amino acids in length, or, where not specified, across the entire sequence of a polypeptide sequence. In addition, by way of example only, two or more polynucleotide sequences are identical when the nucleic acid residues are the same, while two or more polynucleotide sequences are “substantially identical” if the nucleic acid residues are about 60% identical, about 65% identical, about 70% identical, about 75% identical, about 80% identical, about 85% identical, about 90% identical, or about 95% identical over a specified region. The identity can exist over a region that is at least about 75 to about 100 nucleic acids in length, over a region that is about 50 nucleic acids in length, or, where not specified, across the entire sequence of a polynucleotide sequence. The term “immunogenicity,” as used herein, refers to an antibody response to administration of a therapeutic drug. The immunogenicity toward therapeutic non-natural amino acid polypeptides WSGR Ref. No: 31362-826.601 can be obtained using quantitative and qualitative assays for detection of anti-non-natural amino acid polypeptides antibodies in biological fluids. Such assays include, but are not limited to, Radioimmunoassay (RIA), Enzyme-linked immunosorbent assay (ELISA), luminescent immunoassay (LIA), and fluorescent immunoassay (FIA). Analysis of immunogenicity toward therapeutic non-natural amino acid polypeptides involves comparing the antibody response upon administration of therapeutic non-natural amino acid polypeptides to the antibody response upon administration of therapeutic natural amino acid polypeptides. The term “isolated” as used herein refers to separating and removing a component of interest from components not of interest. Isolated substances can be in either a dry or semi-dry state, or in solution, including but not limited to an aqueous solution. The isolated component can be in a homogeneous state or the isolated component can be a part of a pharmaceutical composition that comprises additional pharmaceutically acceptable carriers and/or excipients. Purity and homogeneity may be determined using analytical chemistry techniques including, but not limited to, polyacrylamide gel electrophoresis or high-performance liquid chromatography. In addition, when a component of interest is isolated and is the predominant species present in a preparation, the component is described herein as substantially purified. The term “purified,” as used herein, may refer to a component of interest which is at least 85% pure, at least 90% pure, at least 95% pure, at least 99% or greater pure. By way of example only, nucleic acids or proteins are “isolated” when such nucleic acids or proteins are free of at least some of the cellular components with which it is associated in the natural state, or that the nucleic acid or protein has been concentrated to a level greater than the concentration of its in vivo or in vitro production. Also, by way of example, a gene is isolated when separated from open reading frames which flank the gene and encode a protein other than the gene of interest. The term “label” as used herein, refers to a substance which is incorporated into a compound and is readily detected, whereby its physical distribution may be detected and/or monitored. The term “linkage” or “adduct moiety” as used herein refers to a bond or chemical moiety formed from a chemical reaction between the functional group of one group, such as a linker of the present disclosure, and another molecule. Such bonds may include, but are not limited to, covalent linkages and non-covalent bonds, while such chemical moieties may include, but are not limited to, esters, carbonates, imines, phosphate esters, hydrazones, acetals, orthoesters, peptide linkages, oximes and oligonucleotide linkages. Hydrolytically stable linkages mean that the linkages are substantially stable in water and do not react with water at useful pH values, including but not limited to, under physiological conditions for an extended period of time, perhaps even indefinitely. Hydrolytically unstable or degradable linkages mean that the linkages are degradable in water or in WSGR Ref. No: 31362-826.601 aqueous solutions, including for example, blood. Enzymatically unstable or degradable linkages mean that the linkage can be degraded by one or more enzymes. By way of example only, PEG and related polymers may include degradable linkages in the polymer backbone or in the linker group between the polymer backbone and one or more of the terminal functional groups of the polymer molecule. Such degradable linkages include but are not limited to ester linkages formed by the reaction of PEG carboxylic acids or activated PEG carboxylic acids with alcohol groups on a biologically active agent, wherein such ester groups generally hydrolyze under physiological conditions to release the biologically active agent. Other hydrolytically degradable linkages include but are not limited to carbonate linkages; imine linkages resulted from reaction of an amine and an aldehyde; phosphate ester linkages formed by reacting an alcohol with a phosphate group; hydrazone linkages which are reaction product of a hydrazide and an aldehyde; acetal linkages that are the reaction product of an aldehyde and an alcohol; orthoester linkages that are the reaction product of a formate and an alcohol; peptide linkages formed by an amine group, including but not limited to, at an end of a polymer such as PEG, and a carboxyl group of a peptide; and oligonucleotide linkages formed by a phosphoramidite group, including but not limited to, at the end of a polymer, and a 5' hydroxyl group of an oligonucleotide. The term “linker” as used herein refers to any multivalent group that connects, or is capable of connecting, a first group to at least one other group. Typically, a linker is a bivalent or a trivalent organic moiety that connects a drug (first group) to a biologically active agent (second group), e.g., via a linkage or adduct moiety, or that connects a drug (first group) to a reactive moiety (second group), wherein the reactive moiety is capable of reacting with a biologically active agent. Linkers can be susceptible to cleavage (cleavable linkers), such as, acid-induced cleavage, photo-induced cleavage, peptidase-induced cleavage, esterase-induced cleavage, and disulfide bond cleavage, and so on, at conditions under which the drug and the at least one other group remains active. Alternatively, linkers can be substantially resistant to cleavage (e.g., stable linker or non-cleavable linker). In some embodiments, the linker is a bivalent or trivalent group comprising, or consisting of, at least one moiety, wherein each at least one moiety is independently selected from the group consisting of a bond, unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -C(S)-, -N(Rw)-, -S(O)0-2-, methine (-CH)-, an amino acid, a peptide, a disulfide (-S-S-) and a phosphate-containing moiety; and combinations thereof; wherein: each nn is independently an integer from 1 to 100; each Rw is independently H, C1-C8 alkyl or a bond; and each phosphate-containing moiety is independently selected from the group consisting of a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a WSGR Ref. No: 31362-826.601 diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate and a diphosphorthioate. Unless expressly indicated otherwise, no orientation of the linker is implied by the direction in which the formula of the linker group is written. By way of example, the formula –C(O)CH2CH2– represents both –C(O)CH2CH2– and –CH2CH2C(O)–. In another example, the formula –C(O)CH2CH2– represents both *– C(O)CH2CH2– and –C(O)CH2CH2–*, wherein * denotes a point of connection, for example, connection to a drug. In some embodiments, when a selected moiety occurs two or more times in the same linker, the two or more occurrences are not adjacent. In some embodiments, a linker is not a bond. In some embodiments, a linker is a bivalent moiety that connects a first group and a second group. In some other embodiments, the linker is a trivalent moiety that connects a first group, a second group and a third group. In a non-limiting example, a trivalent moiety is C(H) (i.e., methine) or N. In some other embodiments, a linker is a tetravalent moiety that connects a first group, a second group and a third group. In some embodiments, a linker connects at least a first group and a second group, wherein the first group is a drug, and the second group is a biologically active polypeptide or protein. In some embodiments, the biologically active polypeptide or protein contains at least one non-natural amino acid. In some embodiments, the linker connects the drug to a non-natural amino acid of the biologically active polypeptide or protein. In some embodiments, the biologically active polypeptide or protein is an antibody. Thus, the antibody connected to a drug via a linker can be an antibody- drug conjugate (ADC), such as an ADC of the present disclosure. In some other embodiments, a linker connects at least a first group and a second group, wherein the first group is a drug, and the second group is a reactive moiety. In some embodiments, the second group is a reactive moiety that is capable of reacting with a biologically active polypeptide or protein. In some embodiments, the biologically active polypeptide or protein contains at least one non-natural amino acid. Thus, in some embodiments, the reactive moiety is capable of reacting with a non-natural amino acid of the biologically active polypeptide or protein. In some embodiments, the biologically active polypeptide or protein is an antibody. In some embodiments, a first linker is connected to a second linker, and the combined linkers (a composite linker) connects at least a first group and a second group. A composite linker of the present disclosure can contain 2, 3, 4, 5, 6, 7, 8, 9, 10 or more linker groups. In a non-limiting example, a first, second and third linker group are joined together to provide a composite linker that can connect a first group (e.g., a drug) to at least one other group, such as a reactive moiety and/or a WSGR Ref. No: 31362-826.601 biologically active polypeptide or protein (e.g., an antibody. In some embodiments, the biologically active polypeptide or protein (e.g., antibody) contains a non-natural amino acid. In some embodiments, a linker is linear. In other embodiments, a linker is branched. In some embodiments, a linker is a phosphate-based linker. The term “phosphate-based linker” as used herein refers to a linker comprising a phosphate- based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate and/or a diphosphorthioate. The terms “medium” or “media” as used herein refer to any culture medium used to grow and harvest cells and/or products expressed and/or secreted by such cells. Such “medium” or “media” include, but are not limited to, solution, solid, semi-solid, or rigid supports that may support or contain any host cell, including, by way of example, bacterial host cells, yeast host cells, insect host cells, plant host cells, eukaryotic host cells, mammalian host cells, CHO cells, prokaryotic host cells, E. coli, or Pseudomonas host cells, and cell contents. Such “medium” or “media” includes, but is not limited to, medium or media in which the host cell has been grown into which a polypeptide has been secreted, including medium either before or after a proliferation step. Such “medium” or “media” also includes, but is not limited to, buffers or reagents that contain host cell lysates, by way of example a polypeptide produced intracellularly, and the host cells are lysed or disrupted to release the polypeptide. The term “metabolite” as used herein refers to a derivative of a compound, by way of example natural amino acid polypeptide, a non-natural amino acid polypeptide, a modified natural amino acid polypeptide, or a modified non-natural amino acid polypeptide, that is formed when the compound, by way of example natural amino acid polypeptide, non-natural amino acid polypeptide, modified natural amino acid polypeptide, or modified non-natural amino acid polypeptide, is metabolized. The term “pharmaceutically active metabolite” or “active metabolite” refers to a biologically active derivative of a compound, by way of example natural amino acid polypeptide, a non-natural amino acid polypeptide, a modified natural amino acid polypeptide, or a modified non-natural amino acid polypeptide, that is formed when such a compound, by way of example a natural amino acid polypeptide, non-natural amino acid polypeptide, modified natural amino acid polypeptide, or modified non-natural amino acid polypeptide, is metabolized. The term “pharmaceutically active metabolite” or “active metabolite” also refers to biologically active derivatives of a compound, by way of example metabolizing phosphate linkages including monophosphate, diphosphate, pyrophosphate and triphosphate but not limited to such. WSGR Ref. No: 31362-826.601 The term “metabolized,” as used herein, refers to the sum of the processes by which a particular substance is changed by an organism. Such processes include, but are not limited to, hydrolysis reactions and reactions catalyzed by enzymes. Further information on metabolism may be obtained from The Pharmacological Basis of Therapeutics, 9th Edition, McGraw-Hill (1996). By way of example only, metabolites of natural amino acid polypeptides, non-natural amino acid polypeptides, modified natural amino acid polypeptides, or modified non-natural amino acid polypeptides may be identified either by administration of the natural amino acid polypeptides, non- natural amino acid polypeptides, modified natural amino acid polypeptides, or modified non-natural amino acid polypeptides to a host and analysis of tissue samples from the host, or by incubation of natural amino acid polypeptides, non-natural amino acid polypeptides, modified natural amino acid polypeptides, or modified non-natural amino acid polypeptides with hepatic cells in vitro and analysis of the resulting compounds. The term “modified,” as used herein refers to the presence of a change to a natural amino acid, a non-natural amino acid, a natural amino acid polypeptide or a non-natural amino acid polypeptide. Such changes, or modifications, may be obtained by post synthesis modifications of natural amino acids, non-natural amino acids, natural amino acid polypeptides or non-natural amino acid polypeptides, or by co-translational, or by post-translational modification of natural amino acids, non-natural amino acids, natural amino acid polypeptides or non-natural amino acid polypeptides. As used herein, the term “modulated serum half-life” refers to positive or negative changes in the circulating half-life of a modified biologically active molecule relative to its non-modified form. By way of example, the modified biologically active molecules include, but are not limited to, natural amino acid, non-natural amino acid, natural amino acid polypeptide or non-natural amino acid polypeptide. By way of example, serum half-life is measured by taking blood samples at various time points after administration of the biologically active molecule or modified biologically active molecule and determining the concentration of that molecule in each sample. Correlation of the serum concentration with time allows calculation of the serum half-life. By way of example, modulated serum half-life may be an increased in serum half-life, which may enable an improved dosing regimen or avoid toxic effects. Such increases in serum may be at least about two-fold, at least about three-fold, at least about five-fold, or at least about ten-fold. Methods for evaluating serum half-life are known in the art and may be used for evaluating the serum half-life of antibodies and antibody drug conjugates of the present disclosure. The term “modulated therapeutic half-life” as used herein refers to positive or negative change in the half-life of the therapeutically effective amount of a modified biologically active molecule, relative to its non-modified form. By way of example, the modified biologically active WSGR Ref. No: 31362-826.601 molecules include, but are not limited to, natural amino acid, non-natural amino acid, natural amino acid polypeptide or non-natural amino acid polypeptide. By way of example, therapeutic half-life is measured by measuring pharmacokinetic and/or pharmacodynamic properties of the molecule at various time points after administration. Increased therapeutic half-life may enable a particular beneficial dosing regimen, a particular beneficial total dose, or avoids an undesired effect. By way of example, the increased therapeutic half-life may result from increased potency, increased or decreased binding of the modified molecule to its target, an increase or decrease in another parameter or mechanism of action of the non-modified molecule, or an increased or decreased breakdown of the molecules by enzymes such as, by way of example only, proteases. Methods for evaluating therapeutic half-life are known in the art and may be used for evaluating the therapeutic half-life of antibodies and antibody drug conjugates of the present disclosure. The term “nanoparticle” as used herein refers to a particle which has a particle size of within a range of about 0.1 nm to about 1000 nm. In some embodiments, the nanoparticle has a particle size of within a range of about 0.1 nm to about 750 nm. In some embodiments, the nanoparticle has a particle size of within a range of about 1 nm to about 500 nm. As used herein, the term “non-eukaryote” refers to non-eukaryotic organisms. By way of example, a non-eukaryotic organism may belong to the Eubacteria, (which includes but is not limited to, Escherichia coli, Thermus thermophilus, or Bacillus stearothermophilus, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas putida), phylogenetic domain, or the Archaea, which includes, but is not limited to, Methanococcus jannaschii, Methanobacterium thermoautotrophicum, Archaeoglobus fulgidus, Pyrococcus furiosus, Pyrococcus horikoshii, Aeuropyrum pernix, or Halobacterium such as Haloferax volcanii and Halobacterium species NRC- 1, or phylogenetic domain. The term “non-natural amino acid” as used herein refers to an amino acid that is not one of the 20 common amino acids or pyrolysine or selenocysteine. Other terms that may be used synonymously with the term “non-natural amino acid” herein include “non-naturally encoded amino acid,” “unnatural amino acid,” “non-naturally-occurring amino acid,” and variously hyphenated and non-hyphenated versions thereof. The term “non-natural amino acid” includes, but is not limited to, amino acids which occur naturally by modification of a naturally encoded amino acid (including but not limited to, the 20 common amino acids or pyrrolysine and selenocysteine) but are not themselves incorporated into a growing polypeptide chain by the translation complex. Examples of naturally- occurring amino acids that are not naturally-encoded include, but are not limited to, N- acetylglucosaminyl-L-serine, N-acetylglucosaminyl-L-threonine, and O-phosphotyrosine. Additionally, the term “non-natural amino acid” includes, but is not limited to, amino acids which do WSGR Ref. No: 31362-826.601 not occur naturally and may be obtained synthetically or may be obtained by modification of non- natural amino acids. The term “nucleic acid” as used herein refers to deoxyribonucleotides, deoxyribonucleosides, ribonucleosides or ribonucleotides and polymers thereof in either single- or double-stranded form. By way of example only, such nucleic acids and nucleic acid polymers include, but are not limited to, (i) analogues of natural nucleotides which have similar binding properties as a reference nucleic acid and are metabolized in a manner similar to naturally occurring nucleotides; (ii) oligonucleotide analogs including, but are not limited to, PNA (peptidonucleic acid), analogs of DNA used in antisense technology (phosphorothioates, phosphoroamidates, and the like); (iii) conservatively modified variants thereof (including but not limited to, degenerate codon substitutions) and complementary sequences and sequence explicitly indicated. By way of example, degenerate codon substitutions may be achieved by generating sequences in which the third position of one or more selected (or all) codons is substituted with mixed-base and/or deoxyinosine residues (Batzer et al., Nucleic Acid Res.19:5081, 1991; Ohtsuka et al., J. Biol. Chem.260:2605-2608, 1985; and Rossolini et al., Mol. Cell. Probes 8:91-98, 1994). The term “optionally substituted” as used herein means substituted or unsubstituted. Thus, when a substance, group or moiety is defined as optionally substituted, the substance, group or moiety can be a substituted group or an unsubstituted group. By way of example only, optionally substituted alkyl includes substituted alkyl and unsubstituted alkyl. Accordingly, the terms “substituted and unsubstituted” and “optionally substituted” may be used interchangeably. The term “oxidizing agent,” as used herein, refers to a compound or material which is capable of removing an electron from a compound being oxidized. By way of example oxidizing agents include, but are not limited to, oxidized glutathione, cystine, cystamine, oxidized dithiothreitol, oxidized erythreitol, and oxygen. A wide variety of oxidizing agents are suitable for use in the methods and compositions described herein. The term “pharmaceutically acceptable” as used herein refers to a material, including but not limited, to a salt, binder, adjuvant, excipient, carrier or diluent, which does not abrogate the biological activity or properties of the compound, and is relatively nontoxic, i.e., the material may be administered to an individual without causing undesirable biological effects or interacting in a deleterious manner with any of the components of the composition in which it is contained. The term “photocleavable group” as used herein refers to a group which breaks upon exposure to light. WSGR Ref. No: 31362-826.601 The term “photocrosslinker” as used herein refers to a compound comprising two or more functional groups which, upon exposure to light, are reactive and form a covalent or non-covalent linkage with two or more monomeric or polymeric molecules. The term “polymer” as used herein refers to a molecule composed of repeated subunits. Such molecules include, but are not limited to, polypeptides, polynucleotides, or polysaccharides or polyalkylene glycols. Polymers of the disclosure can be linear or branched polymeric polyether polyols including, but are not limited to, polyethylene glycol, polypropylene glycol, polybutylene glycol, and derivatives thereof. Other exemplary embodiments are listed, for example, in commercial supplier catalogs, such as Shearwater Corporation's catalog “Polyethylene Glycol and Derivatives for Biomedical Applications” (2001). By way of example only, such polymers have average molecular weights between about 0.1 kDa to about 100 kDa. Such polymers include, but are not limited to, between about 100 Da and about 100,000 Da or more. The molecular weight of the polymer may be between about 100 Da and about 100,000 Da, including but not limited to, about 100,000 Da, about 95,000 Da, about 90,000 Da, about 85,000 Da, about 80,000 Da, about 75,000 Da, about 70,000 Da, about 65,000 Da, about 60,000 Da, about 55,000 Da, about 50,000 Da, about 45,000 Da, about 40,000 Da, about 35,000 Da, about 30,000 Da, about 25,000 Da, about 20,000 Da, about 15,000 Da, about 10,000 Da, about 9,000 Da, about 8,000 Da, about 7,000 Da, about 6,000 Da, about 5,000 Da, about 4,000 Da, about 3,000 Da, about 2,000 Da, about 1,000 Da, about 900 Da, about 800 Da, about 700 Da, about 600 Da, about 500 Da, 400 Da, about 300 Da, about 200 Da, and about 100 Da. In some embodiments molecular weight of the polymer is between about 100 Da and about 50,000 Da. In some embodiments, the molecular weight of the polymer is between about 100 Da and about 40,000 Da. In some embodiments, the molecular weight of the polymer is between about 1,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the polymer is between about 2,000 to about 50,000 Da. In some embodiments, the molecular weight of the polymer is between about 5,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the polymer is between about 10,000 Da and about 40,000 Da. In some embodiments, the poly(ethylene glycol) molecule is a branched polymer. The molecular weight of the branched chain PEG may be between about 1,000 Da and about 100,000 Da, including but not limited to, about 100,000 Da, about 95,000 Da, about 90,000 Da, about 85,000 Da, about 80,000 Da, about 75,000 Da, about 70,000 Da, about 65,000 Da, about 60,000 Da, about 55,000 Da, about 50,000 Da, about 45,000 Da, about 40,000 Da, about 35,000 Da, about 30,000 Da, about 25,000 Da, about 20,000 Da, about 15,000 Da, about 10,000 Da, about 9,000 Da, about 8,000 Da, about 7,000 Da, about 6,000 Da, about 5,000 Da, about 4,000 Da, about 3,000 Da, about 2,000 Da, and about 1,000 Da. In some embodiments, the molecular weight of the branched chain PEG is between about 1,000 Da and about 50,000 Da. In some WSGR Ref. No: 31362-826.601 embodiments, the molecular weight of the branched chain PEG is between about 1,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the branched chain PEG is between about 5,000 Da and about 40,000 Da. In some embodiments, the molecular weight of the branched chain PEG is between about 5,000 Da and about 20,000 Da. In other embodiments, the molecular weight of the branched chain PEG is between about 2,000 to about 50,000 Da. The term “PEGylating” or “PEGylated” is meant to refer to the covalent bonding of the specified synthetic amino acid to a polyethylene glycol (PEG) molecule. The method can comprise contacting an isolated polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety that reacts with polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety ADC polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a CD70 ADC polypeptide comprising a synthetic amino acid with a water-soluble polymer comprising a moiety that reacts with the synthetic amino acid. The terms “polypeptide,” “peptide” and “protein” are used interchangeably herein to refer to a polymer of amino acid residues. That is, a description directed to a polypeptide applies equally to a description of a peptide and a description of a protein, and vice versa. The terms apply to naturally occurring amino acid polymers as well as amino acid polymers in which one or more amino acid residues is a non-natural amino acid. Additionally, such “polypeptides,” “peptides” and “proteins” include amino acid chains of any length, including full length proteins, wherein the amino acid residues are linked by covalent peptide bonds. In some embodiments, a “peptide” can refer to a polymer of 2 to 12 amino acids, wherein the amino acid residues are linked by covalent peptide bonds. In some embodiments, a peptide contains 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 amino acids. In some embodiments, a peptide contains 2, 3, 4, 5 or 6 amino acids. In some embodiments, a peptide contains 2, 3 or 4 amino acids; non-limiting examples include a dipeptide, a tripeptide and a tetrapeptide. The term “post-translationally modified” refers to any modification of a natural or non-natural amino acid which occurs after such an amino acid has been translationally incorporated into a polypeptide chain. Such modifications include, but are not limited to, co-translational in vivo modifications, co-translational in vitro modifications (such as in a cell-free translation system), post- translational in vivo modifications, and post-translational in vitro modifications. The term “prodrug” or “pharmaceutically acceptable prodrug” as used herein refers to an agent that is converted into the parent drug in vivo or in vitro, which does not abrogate the biological WSGR Ref. No: 31362-826.601 activity or properties of the drug, and is relatively nontoxic, i.e., the material may be administered to an individual without causing undesirable biological effects or interacting in a deleterious manner with any of the components of the composition in which it is contained. Prodrugs are generally drug precursors that, following administration to a subject and subsequent absorption, are converted to an active, or a more active species via some process, such as conversion by a metabolic pathway. Some prodrugs have a chemical group present on the prodrug that renders it less active and/or confers solubility or some other property to the drug. Once the chemical group has been cleaved and/or modified from the prodrug the active drug is generated. Prodrugs are converted into active drug within the body through enzymatic or non-enzymatic reactions. Prodrugs may provide improved physiochemical properties such as better solubility, enhanced delivery characteristics, such as specifically targeting a particular cell, tissue, organ or ligand, and improved therapeutic value of the drug. The benefits of such prodrugs include, but are not limited to, (i) ease of administration compared with the parent drug; (ii) the prodrug may be bioavailable by oral administration whereas the parent is not; and (iii) the prodrug may also have improved solubility in pharmaceutical compositions compared with the parent drug. A prodrug includes a pharmacologically inactive, or reduced activity, derivative of an active drug. Prodrugs may be designed to modulate the amount of a drug or biologically active molecule that reaches a desired site of action through the manipulation of the properties of a drug, such as physiochemical, biopharmaceutical, or pharmacokinetic properties. An example, without limitation, of a prodrug would be a non-natural amino acid polypeptide which is administered as an ester (the “prodrug”) to facilitate transmittal across a cell membrane where water solubility is detrimental to mobility and that is then metabolically hydrolyzed to the carboxylic acid, the active entity, once inside the cell where water solubility is beneficial. Prodrugs may be designed as reversible drug derivatives, for use as modifiers to enhance drug transport to site-specific tissues. The term “prophylactically effective amount” as used herein refers to an amount of a composition containing at least one non-natural amino acid polypeptide or at least one modified non- natural amino acid polypeptide prophylactically applied to a patient which will relieve to some extent one or more of the symptoms of a disease, condition or disorder being treated. In such prophylactic applications, such amounts may depend on the patient's state of health, weight, and the like. It is considered well within the skill of the art for one to determine such prophylactically effective amounts by routine experimentation, including, but not limited to, a dose escalation clinical trial. The term “protected,” as used herein, refers to the presence of a “protecting group” or moiety that prevents reaction of the chemically reactive functional group under certain reaction conditions. The protecting group will vary depending on the type of chemically reactive group being protected. WSGR Ref. No: 31362-826.601 By way of example only, (i) if the chemically reactive group is an amine or a hydrazide, the protecting group may be selected from tert-butyloxycarbonyl (t-Boc) and 9-fluorenylmethoxycarbonyl (Fmoc); (ii) if the chemically reactive group is a thiol, the protecting group may be orthopyridyldisulfide; and (iii) if the chemically reactive group is a carboxylic acid, such as butanoic or propionic acid, or a hydroxyl group, the protecting group may be benzyl or an alkyl group such as methyl, ethyl, or tert- butyl. By way of example only, blocking/protecting groups may be selected from:
Figure imgf000055_0001
Additionally, protecting groups include, but are not limited to, including photolabile groups such as Nvoc and MeNvoc and other protecting groups known in the art. Other protecting groups are described in Greene and Wuts, Protective Groups in Organic Synthesis, 3rd Ed., John Wiley & Sons, New York, NY, 1999, which is incorporated herein by reference in its entirety. The term “reactive compound,” as used herein, refers to a compound which under appropriate conditions is reactive toward another atom, molecule or compound. The term “recombinant host cell” (optionally referred to as “host cell” herein) refers to a cell which includes an exogenous polynucleotide, wherein the methods used to insert the exogenous polynucleotide into a cell include, but are not limited to, direct uptake, transduction, f-mating, or other methods known in the art to create recombinant host cells. By way of example only, such exogenous polynucleotide may be a nonintegrated vector, including but not limited to a plasmid, or may be integrated into the host genome. The term “redox-active agent” as used herein refers to a molecule which oxidizes or reduces another molecule, whereby the redox active agent becomes reduced or oxidized. Examples of redox active agent include, but are not limited to, ferrocene, quinones, Ru2+/3+ complexes, Co2+/3+ complexes, and Os2+/3+ complexes. In some embodiments, a redox-active agent is a redox-active amino acid. The term “reducing agent” as used herein refers to a compound or material which is capable of adding an electron to a compound being reduced. By way of example reducing agents include, but WSGR Ref. No: 31362-826.601 are not limited to, dithiothreitol (DTT), 2-mercaptoethanol, dithioerythritol, cysteine, cysteamine (2- aminoethanethiol), and reduced glutathione. Such reducing agents may be used, by way of example only, to maintain sulfhydryl groups in the reduced state and to reduce intra- or intermolecular disulfide bonds. The term “resin” as used herein refers to high molecular weight, insoluble polymer beads. By way of example only, such beads may be used as supports for solid phase peptide synthesis, or sites for attachment of molecules prior to purification. The term “saccharide,” as used herein, refers to a series of carbohydrates including but not limited to sugars, monosaccharides, oligosaccharides, and polysaccharides. The term “safety” or “safety profile” as used herein, refers to side effects that might be related to administration of a drug relative to the number of times the drug has been administered. By way of example, a drug which has been administered many times and produced only mild or no side effects is said to have an excellent safety profile. The term “subject” as used herein, refers to an animal which is the object of treatment, observation or experiment. By way of example only, a subject may be, but is not limited to, a mammal including, but not limited to, a human. The term “substantially purified,” as used herein, refers to a component of interest that may be substantially or essentially free of other components which normally accompany or interact with the component of interest prior to purification. By way of example only, a component of interest may be “substantially purified” when the preparation of the component of interest contains less than about 30%, less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 5%, less than about 4%, less than about 3%, less than about 2%, or less than about l% (by dry weight) of contaminating components. Thus, a “substantially purified” component of interest may have a purity level of about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 96%, about 97%, about 98%, about 99% or greater. By way of example only, a natural amino acid polypeptide or a non-natural amino acid polypeptide may be purified from a native cell, or host cell in the case of recombinantly produced natural amino acid polypeptides or non-natural amino acid polypeptides. By way of example a preparation of a natural amino acid polypeptide or a non-natural amino acid polypeptide may be “substantially purified” when the preparation contains less than about 30%, less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 5%, less than about 4%, less than about 3%, less than about 2%, or less than about l% (by dry weight) of contaminating material. By way of example when a natural amino acid polypeptide or a non-natural amino acid polypeptide is recombinantly produced by host cells, the natural amino acid polypeptide or non-natural amino acid polypeptide may be present at about 30%, about 25%, about WSGR Ref. No: 31362-826.601 20%, about 15%, about 10%, about 5%, about 4%, about 3%, about 2%, or about 1% or less of the dry weight of the cells. By way of example when a natural amino acid polypeptide or a non-natural amino acid polypeptide is recombinantly produced by host cells, the natural amino acid polypeptide or non-natural amino acid polypeptide may be present in the culture medium at about 5g/L, about 4g/L, about 3g/L, about 2g/L, about 1g/L, about 750mg/L, about 500mg/L, about 250mg/L, about 100mg/L, about 50mg/L, about 10mg/L, or about 1mg/L or less of the dry weight of the cells. By way of example, “substantially purified” natural amino acid polypeptides or non-natural amino acid polypeptides may have a purity level of about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99% or greater as determined by appropriate methods, including, but not limited to, SDS/PAGE analysis, RP-HPLC, SEC, and capillary electrophoresis. The term “substituent(s)” refers to group(s) which can be used to replace another group on a molecule. Such substituent groups include, but are not limited to, halogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C1-C10 alkoxy, substituted C1-C10 alkoxy, C5-C12 aralkyl, C3-C12 cycloalkyl, C4-C12 cycloalkenyl, C2-C12 alkoxyalkyl, C5-C12 alkoxyaryl, C5-C12 aryloxyalkyl, C7-C12 oxyaryl, C1-C6 alkylsulfinyl, C1-C10 alkylsulfonyl, wherein m is from 1 to 8, aryl, substituted aryl (including but not limited to phenyl or substituted phenyl), haloalkyl (including but not limited to fluoroalkyl), heterocyclic radical, substituted heterocyclic radical, nitroalkyl, -SiR3, -NO2, -N3, -ONH2, -CN, - NRC(O)-(C1-C10 alkyl), -C(O)-(C1-C10 alkyl), C2-C10 alkthioalkyl, -C(O)O-(C1-C10 alkyl), -OH, -OR, -SR, -SO2, -S(O)R, -S(O)2R, -S(O)2NR2, -NRSO2R, , =NR, =N-OR, -OC(O)R, -C(O)R, -CO2R, - CONR2, -OC(O)NR2, -NRC(O)R, -NRC(O)NR2, -NR(O)2R, -NR-C(NR2)=NR, =S, -COOH, -NR2, carbonyl (-C(O)), -C(O)-(C1-C10 alkyl)-CF3, -C(O)-CF3, -C(O)NR2, -(C1-C10 aryl)-S-(C6-C10 aryl), - C(O)-(C6-C10 aryl), -(CH2)m-O-(CH2)m-O-(C1-C10 alkyl), -(CH2)m-O-(C1-C10 alkyl), -C(O)NR2, - C(S)NR2, -SO2NR2, -NRC(O)NR2, -NRC(S)NR2, a sugar; wherein each m is from 1 to 8; salts thereof, and the like. Each R group in the preceding list includes, but is not limited to, H, alkyl, substituted alkyl, aryl, substituted aryl, halogen or alkaryl. Where substituent groups are specified by their conventional chemical formulas, written from left to right, they equally encompass the chemically identical substituents that would result from writing the structure from right to left; for example, - CH2O- is equivalent to –OCH2-. By way of example only, substituents for alkyl and heteroalkyl radicals (including those groups referred to as alkylene, alkenyl, heteroalkylene, heteroalkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl) include, but are not limited to: -OR, =O, =NR, =N-OR, -NR2, -SR, -halogen, -SiR3, -OC(O)R, -C(O)R, -CO2R, -CONR2, -OC(O)NR2, - NRC(O)R, -NRC(O)NR2, -NR(O)2R, -NR-C(NR2)=NR, -S(O)R, -S(O)2R, -S(O)2NR2, -NRSO2R, - WSGR Ref. No: 31362-826.601 CN, –NO2, -R, -N3, -ONH2, -CH(Ph)2, fluoro(C1-C4)alkoxy, fluoro(C1-C4)alkyl, a sugar, in a number ranging from zero to the total number of open valences on the alkyl or heteroalkyl group, and wherein each R group in the preceding list includes, but is not limited to, hydrogen, substituted or unsubstituted heteroalkyl, substituted or unsubstituted aryl, including but not limited to, aryl substituted with 1-3 halogens, substituted or unsubstituted alkyl, alkoxy or thioalkoxy groups, or aralkyl groups. When two R groups are attached to the same nitrogen atom, they can be combined with the nitrogen atom to form a 5-, 6-, or 7-membered ring. For example, -NR2 is meant to include, but not be limited to, 1-pyrrolidinyl and 4-morpholinyl. By way of example, substituents for aryl and heteroaryl groups (including those groups referred to as arylene) include, but are not limited to, -OR, =O, =NR, =N-OR, -NR2, -SR, -halogen, -SiR3, -OC(O)R, -C(O)R, -CO2R, -CONR2, -OC(O)NR2, -NRC(O)R, -NRC(O)NR2, -NR(O)2R, - NR-C(NR2)=NR, -S(O)R, -S(O)2R, -S(O)2NR2, -NRSO2R, -CN, –NO2, -R, -N3, -ONH2, -CH(Ph)2, fluoro(C1-C4)alkoxy, fluoro(C1-C4)alkyl, a sugar, in a number ranging from zero to the total number of open valences on the aromatic ring system; and wherein each R group in the preceding list includes, but is not limited to, and is independently selected from hydrogen, alkyl, halogen, heteroalkyl, aryl and heteroaryl. The term “therapeutically effective amount,” as used herein, refers to the amount of a composition containing at least one non-natural amino acid polypeptide and/or at least one modified non-natural amino acid polypeptide administered to a patient already suffering from a disease, condition or disorder, sufficient to cure or at least partially arrest, or relieve to some extent one or more of the symptoms of the disease, disorder or condition being treated. The effectiveness of such compositions depends on conditions including, but not limited to, the severity and course of the disease, disorder or condition, previous therapy, the patient's health status and response to the drugs, and the judgment of the treating physician. By way of example only, therapeutically effective amounts may be determined by routine experimentation, including but not limited to a dose escalation clinical trial. The term “toxic”, or “toxic moiety” or “toxic group” or “cytotoxic” or “cytotoxic payload” or “payload” or “cytotoxic drug” or “drug” as used herein, refers to a cytotoxic compound which can cause harm, disturbances, or death. Toxic moieties include, but are not limited to, a drug comprising or consisting of exatecan, or an analog or derivative thereof. The terms “treat,” “treated,” “treating” or “treatment”, as used herein, include alleviating, preventing, abating or ameliorating a disease or condition symptoms, preventing additional symptoms, ameliorating or preventing the underlying metabolic causes of symptoms, inhibiting the disease or condition, e.g., arresting the development of the disease or condition, relieving the disease WSGR Ref. No: 31362-826.601 or condition, causing regression of the disease or condition, relieving a condition caused by the disease or condition, or stopping the symptoms of the disease or condition. The terms “treat,” “treated,” “treating” or “treatment”, include, but are not limited to, prophylactic and/or therapeutic treatments. The term “treat”, “treated”, “treating” or “treatment” can refer to the decrease, reduction or amelioration of one or more symptoms or conditions or diseases associated with an antigen related or associated cancer. The term “treat”, “treated”, “treating” or “treatment” can refer to the administration of an ADC of the present disclosure to a subject in need thereof to decrease, reduce, improve, alter, relieve, affect or ameliorate an antigen related or associated cancer or disease or symptom or condition, or the predisposition toward a condition. The term "capable of specific binding" refers to protein or peptide (e.g., antibody) binding to a predetermined target substance (e.g., an antigen and/or groups of antigens), e.g. a target substance that is expressed on the surface of a cell; thus the term "binding to a target cell" or "binding to a cancer cell" is to be understand as referring to protein or peptide (e.g., antibody) binding to a predetermined target substance (e.g. antigen or antigens) that is expressed on such a cell. Typically, the protein or peptide (e.g., antibody) binds with an affinity of at least about l x 107 M1, and/or binds to the predetermined target substance (e.g., antigen, antigens or cell) with an affinity that is at least two-fold greater than its affinity for binding to a non-specific control substance (e.g., BSA, casein, non-cancer cells) other than the predetermined target substance or a closely-related target substance. As used herein, the term “water-soluble polymer” refers to any polymer that is soluble in aqueous solvents. Such water-soluble polymers include, but are not limited to, polyethylene glycol, polyethylene glycol propionaldehyde, mono C1-C10 alkoxy or aryloxy derivatives thereof (described in U.S. Patent No.5,252,714 which is incorporated by reference herein), monomethoxy-polyethylene glycol, polyvinyl pyrrolidone, polyvinyl alcohol, polyamino acids, divinylether maleic anhydride, N- (2-Hydroxypropyl)-methacrylamide, dextran, dextran derivatives including dextran sulfate, polypropylene glycol, polypropylene oxide/ethylene oxide copolymer, polyoxyethylated polyol, heparin, heparin fragments, polysaccharides, oligosaccharides, glycans, cellulose and cellulose derivatives, including but not limited to methylcellulose and carboxymethyl cellulose, serum albumin, starch and starch derivatives, polypeptides, polyalkylene glycol and derivatives thereof, copolymers of polyalkylene glycols and derivatives thereof, polyvinyl ethyl ethers, and alpha-beta-poly[(2- hydroxyethyl)-DL-aspartamide, and the like, or mixtures thereof. By way of example only, coupling of such water-soluble polymers to natural amino acid polypeptides or non-natural polypeptides may result in changes including, but not limited to, increased water solubility, increased or modulated serum half-life, increased or modulated therapeutic half-life relative to the unmodified form, increased bioavailability, modulated biological activity, extended circulation time, modulated WSGR Ref. No: 31362-826.601 immunogenicity, modulated physical association characteristics including, but not limited to, aggregation and multimer formation, altered receptor binding, altered binding to one or more binding partners, and altered receptor dimerization or multimerization. In addition, such water-soluble polymers may or may not have their own biological activity. Introduction Antibody-based therapeutics have emerged as important components of therapies for an increasing number of human malignancies in such fields as oncology, immunology, inflammatory and infectious diseases. In most cases, the basis of the therapeutic function is the high degree of specificity and affinity the antibody-based drug has for its target antigen. Arming monoclonal antibodies with drugs, toxins, or radionuclides is yet another strategy by which monoclonal antibodies may induce therapeutic effect. By combining the exquisite targeting specificity of antibody with the tumor killing power of toxic effector molecules, immunoconjugates permit sensitive discrimination between target and normal tissue thereby resulting in fewer side effects than most conventional chemotherapeutic drugs. The toxins utilized can specifically, stably and irreversibly conjugate to unique sites in the antibody. This unique process of conjugation allows for the precise control of the location of the toxin on the antibody, and also the number of toxins conjugated to each antibody. Both features are critical for controlling biophysical characteristics and toxicities associated with ADCs. (See for example Jackson et al., 2014, Tian et al., 2014). Currently ADCs are advancing the field of cancer therapeutics and a number of ADCs targeting various agents have been approved or are in clinical trials. However, ADCs face challenges due to lack of therapeutic index and toxicity. The linker technology for attachment of the cytotoxic drug to an antibody impacts the stability of ADCs during the systemic circulation. The release of free drug in the circulation instead of the release inside the antigen expressing cancer cells can cause ADC potency loss, insufficient immunogenic cancer cell death, and increased toxicity. Therefore, there is a need to design a stable linker such as phosphate-based linkers for drug design and antibody conjugation. ADC Antibodies and Antibody Sequences The present invention provides novel ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence. Further, the present invention provides ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker. In some embodiments, the antibody, antibody fragment or variant thereof binds to a tumor-associated antigen (TAA) selected WSGR Ref. No: 31362-826.601 from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, C-D123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7- H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA- 125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha, and MN/CA IX antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is TROP2 antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is HER2 antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is HER3 antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is PSMA antibody, antibody fragment or variant. In some embodiments, the antibody, antibody fragment or variant thereof is CD70 antibody, antibody fragment or variant. In other embodiments the invention provides anti-TROP2 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence. In some embodiments, the present invention provides anti-TROP2 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker. In other embodiments the invention provides anti-HER2 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence. In some embodiments, the present invention provides anti-HER2 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker. In other embodiments the invention provides anti-HER3 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one or more non- natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence. In some embodiments, the present invention provides anti-HER3 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one or more non- natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence WSGR Ref. No: 31362-826.601 conjugated to drug via a phosphate-based linker. In other embodiments the invention provides anti- PSMA ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence. In some embodiments, the present invention provides anti-PSMA ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker. In other embodiments the invention provides anti-CD70 ADCs comprising antibodies, antibody fragments or variants thereof engineered to have one or more non-natural amino acids incorporated at any desired position in the heavy and/or light chain amino acid sequence. In some embodiments, the present invention provides anti-CD70 ADCs comprising one or more antibodies, antibody fragments or variants thereof engineered to have one, or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker. Antibody or antibody fragments or variants of the disclosure may be human, humanized, engineered, non-human, and/or chimeric antibody or antibody fragments. An antibody or antibody fragment or variant provided herein may comprise two or more amino acid sequences. A first amino acid sequence may comprise a first antibody chain and a second amino acid sequence may comprise a second antibody chain. A first antibody chain may comprise a first amino acid sequence, and a second antibody chain may comprise a second amino acid sequence. A chain of an antibody may refer to an antibody heavy chain, an antibody light chain, or a combination of a region or all of an antibody heavy chain and a region or all of an antibody light chain. As a non-limiting example, an antibody provided herein comprises a heavy chain or fragment or variant thereof, and a light chain or fragment or variant thereof. Two amino acid sequences of an antibody, including two antibody chains, may be connected, attached, or linked by one or more disulfide bonds, a chemical linker, a peptide linker, or a combination thereof. A chemical linker includes a linker via a non-natural amino acid. A chemical linker includes a linker via one or more non-natural amino acids. A chemical linker can include a chemical conjugate. A peptide linker includes any amino acid sequence joining the two amino acid sequences. The peptide linker may comprise 1 or more, 5 or more, 10 or more, 15 or more, 20 or more, 25 or more, 30 or more, 35 or more, 40 or more, 45 or more, 50 or more, 55 or more, 60 or more, 65 or more, 70 or more, 75 or more, 80 or more, 85 or more, 90 or more, 95 or more, 100 or more amino acids. The peptide linker may be a portion of any antibody, including a domain of an antibody, such as a variable domain, CDR1, CDR2, CDR3, and/or a combination of CDRs (complementarity determining regions). In some embodiments a heavy and a light chain are WSGR Ref. No: 31362-826.601 connected, attached, or linked, for example, via a peptide linker. In some cases, a heavy chain and a light chain are connected, for example, by one or more disulfide bonds. Antibodies, antibody fragments and antibody variants of the disclosure may interact or engage with an antigen on an effector cell. The effector cell can include, but is not limited to, an immune cell, a genetically modified cell having increase or decrease cytotoxic activity, a cell involved in the host defense mechanism, an anti-inflammatory cell, a leukocyte, a lymphocyte, a macrophage, an erythrocyte, a thrombocyte, a neutrophil, a monocyte, an eosinophil, a basophil, a mast cell, a NK cell, a B-cell, or a T-cell. In some embodiments the immune cell may be a T cell such as a cytotoxic T cell or natural killer T cell. The antibody or antibody fragment may interact with a receptor on a T-cell such as, but not limited to a T-cell receptor (TCR). The TCR may comprise TCR alpha, TCR beta, TCR gamma, and/or TCR delta or TCR zeta. Antibody or antibody fragments of the disclosure may bind to a receptor on a lymphocyte, dendritic cell, B-cell, macrophage, monocytes, neutrophils and/or NK cells. Antibody or antibody fragments of the disclosure may bind to a cell surface receptor. Antibody or antibody fragments of the disclosure may bind to an antigen receptor, such as for example, a TROP2 antigen receptor, or a HER2 antigen receptor, or a CD70 antigen receptor. Antibody or antibody fragments of the disclosure can be conjugated to a T-cell surface antigen. Some cell surface antigens have a high overexpression pattern in a large number of tumors, making them excellent targets in the development of ADCs. Thus, the present disclosure provides novel anti-TROP2 antibodies, anti-HER2 antibodies, anti-HER3 antibodies, anti-PSMA antibodies, anti-CD70 antibodies, or the corresponding antibody fragments, and antibody-drug conjugates thereof for use as therapeutic agents. Disclosed herein are novel anti-TROP2 antibodies, antibody fragments or variants thereof; anti-HER2 antibodies, antibody fragments or variants thereof; anti- HER3 antibodies, antibody fragments or variants thereof; anti-PSMA antibodies, antibody fragments or variants thereof; and anti-CD70 antibodies, antibody fragments or variants thereof; each with at least one non-natural amino acid or unnaturally encoded amino acid. The present invention provides anti-TROP2 antibodies, antibody fragments or variants thereof; anti-HER2 antibodies, antibody fragments or variants thereof; anti-HER3 antibodies, antibody fragments or variants thereof; anti- PSMA antibodies, antibody fragments or variants thereof; and anti-CD70 antibodies, antibody fragments or variants thereof; each having a non-natural amino acid that facilitate antibody conjugation to a drug or drug-linker. Antibodies, antibody fragments or variants provided in the present disclosure may be human, humanized, engineered, non-human, and/or chimeric antibody or antibody fragments that bind to the extracellular domain of the target antigen, which can be overexpressed in a number of cancers. Thus, novel antibodies, compositions and antibody drug conjugates for the treatment and/or diagnosis of WSGR Ref. No: 31362-826.601 antigen-expressing cancers are beneficial, including but not limited to TROP2 -expressing cancers, HER2-expressing cancers, HER3-expressing cancers, PSMA-expressing cancers and CD70- expressing cancers. Antibodies or antibody fragments or variants disclosed herein include, but are not limited to, analogs, isoforms, mimetics, fragments, or hybrids of anti-TROP2, anti-HER2, anti-HER3, anti- PSMA and anti-CD70. Antibodies or antibody fragments or variants of anti-TROP2, anti-HER2, anti-HER3, anti-PSMA and anti-CD70 of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. Antibodies comprising non-natural amino acids are also disclosed herein. In certain embodiments, the antibody or antibody fragments or variants include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. In some embodiments, the anti-TROP2, or anti-HER2, or anti-HER3, or anti- PSMA, or anti-CD70, antibody or antibody fragments or variants comprises one or more non-natural amino acids. Non-limiting examples of antibodies or antibody fragments or variants of the present disclosure comprise the sequences listed in Tables 1 to 5. In certain embodiments antibody or antibody fragments disclosed herein are anti-TROP2 antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-TROP2 antibodies or antibody fragments or variants disclosed herein can be humanized. Anti-TROP2 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- TROP2 analogs, isoforms, mimetics, fragments, or hybrids. Anti-TROP2 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. The anti-TROP2 antibodies or antibody fragments or variants of the present disclosure comprise a sequence of SEQ ID NOs: 1 to 17 (Table 1). The antibodies, fragments or variants of the present disclosure can be an anti-TROP2 antibody, fragment or variant. In certain embodiments, the anti- TROP2 antibody comprises a heavy chain and light chain amino acid sequence selected from a WSGR Ref. No: 31362-826.601 sequence of SEQ ID NOs: 1 to 17. In certain embodiments, the anti-TROP2 antibody consists of a heavy chain and light chain amino acid sequence selected from a sequence of SEQ ID NOs: 1 to 17. In some embodiments, an anti-TROP2 antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody has an amino acid sequence selected from the group of sequences listed in Table 1. In some embodiments, the anti-TROP2 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 5, wherein SEQ ID NO: 5 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti- TROP2 antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 or 17. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 4. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 11, wherein SEQ ID NO: 11 contains one non-natural amino acid at position 121. In some embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 5; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 4. In some embodiments, an ADC comprising the anti- TROP2 antibody has a drug-to-antibody ratio of about 2. In some other embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 5; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 11. In some embodiments, an ADC comprising the anti-TROP2 antibody has a drug-to-antibody ratio of about 3 WSGR Ref. No: 31362-826.601 or about 4. In some embodiments, each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF). In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 10. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 14. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID WSGR Ref. No: 31362-826.601 NO: 9. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 1 and two light chain amino acid sequences of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 10. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 14. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain WSGR Ref. No: 31362-826.601 amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 2 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 2 and two light chain amino acid sequences of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises WSGR Ref. No: 31362-826.601 a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 10. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 14. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 5 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises two heavy WSGR Ref. No: 31362-826.601 chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 5 and two light chain amino acid sequences of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 10. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 14. In some embodiments, the anti- TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 6 and a light chain amino acid sequence of SEQ ID NO: 17. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 3. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 4. In some embodiments, the WSGR Ref. No: 31362-826.601 anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 7. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 8. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 9. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 10. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 11. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 12. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 13. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 14. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 15. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 16. In some embodiments, the anti-TROP2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 6 and two light chain amino acid sequences of SEQ ID NO: 17. In certain embodiments antibody or antibody fragments disclosed herein are anti-CD70 antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-CD70 antibodies or antibody fragments or variants disclosed herein can be humanized. Anti-CD70 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- CD70 analogs, isoforms, mimetics, fragments, or hybrids. Anti-CD70 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. In some embodiments, an anti-CD70 antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid WSGR Ref. No: 31362-826.601 sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 2. In some embodiments, the anti-CD70 antibody has an amino acid sequence selected from the group of sequences listed in Table 2. In some embodiments, the anti-CD70 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 20, wherein SEQ ID NO: 20 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti- CD70 antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 19, 21, 22, 23 or 24. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 19. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 24, wherein SEQ ID NO: 24 contains one non-natural amino acid at position 121. In some embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 20; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 19. In some embodiments, an ADC comprising the anti-CD70 antibody has a drug-to- antibody ratio of about 2. In some other embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 20; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 24. In some embodiments, an ADC comprising the anti-CD70 antibody has a drug-to-antibody ratio of about 3 or about 4. In some embodiments, each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF). In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 23. WSGR Ref. No: 31362-826.601 In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 18 and a light chain amino acid sequence of SEQ ID NO: 24. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 23. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 18 and two light chain amino acid sequences of SEQ ID NO: 24. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 23. In some embodiments, the anti-CD70 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 20 and a light chain amino acid sequence of SEQ ID NO: 24. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 19. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 21. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 22. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 23. In some embodiments, the anti-CD70 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 20 and two light chain amino acid sequences of SEQ ID NO: 24. In certain embodiments antibody or antibody fragments disclosed herein are anti-HER2 antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-HER2 antibodies or antibody fragments or variants disclosed herein can be humanized. Anti-HER2 WSGR Ref. No: 31362-826.601 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- HER2 analogs, isoforms, mimetics, fragments, or hybrids. Anti-HER2 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. In some embodiments, an anti-HER2 antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 3. In some embodiments, the anti-HER2 antibody has an amino acid sequence selected from the group of sequences listed in Table 3. In some embodiments, the anti-HER2 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 26, wherein SEQ ID NO: 26 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti- HER2 antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 27 or 28. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 27. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 28, wherein SEQ ID NO: 28 contains one non-natural amino acid at position 121. In some embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 26; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 27. In some embodiments, an ADC comprising the anti-HER2 antibody has a drug-to- antibody ratio of about 2. In some other embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID WSGR Ref. No: 31362-826.601 NO: 26; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 28. In some embodiments, an ADC comprising the anti-HER2 antibody has a drug-to-antibody ratio of about 3 or about 4. In some embodiments, each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF). In some embodiments, the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 25 and a light chain amino acid sequence of SEQ ID NO: 27. In some embodiments, the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 25 and a light chain amino acid sequence of SEQ ID NO: 28. In some embodiments, the anti-HER2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 25 and two light chain amino acid sequences of SEQ ID NO: 27. In some embodiments, the anti-HER2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 25 and two light chain amino acid sequences of SEQ ID NO: 28. In some embodiments, the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 26 and a light chain amino acid sequence of SEQ ID NO: 27. In some embodiments, the anti-HER2 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 26 and a light chain amino acid sequence of SEQ ID NO: 28. In some embodiments, the anti-HER2 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 26 and two light chain amino acid sequences of SEQ ID NO: 27. In some embodiments, the anti-HER2 antibody comprises two heavy chain amino acid sequence of SEQ ID NO: 26 and two light chain amino acid sequences of SEQ ID NO: 28. In certain embodiments antibody or antibody fragments disclosed herein are anti-PSMA antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-PSMA antibodies or antibody fragments or variants disclosed herein can be humanized. Anti-PSMA antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti-PSMA analogs, isoforms, mimetics, fragments, or hybrids. Anti-PSMA antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. In some embodiments, an anti-PSMA antibody of the present disclosure has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid WSGR Ref. No: 31362-826.601 sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 4. In some embodiments, the anti-PSMA antibody has an amino acid sequence selected from the group of sequences listed in Table 4. In some embodiments, the anti-PSMA antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 36, wherein SEQ ID NO: 36 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti- PSMA antibody further comprise one or more light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 37, 39, 41, 43 and 45. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 37. In some embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 36; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 37. In some embodiments, an ADC comprising the anti-PSMA antibody has a drug- to-antibody ratio of about 2. In some embodiments, an ADC comprising the anti-PSMA antibody has a drug-to-antibody ratio of about 3 or about 4. In some embodiments, each said non-natural amino acid is para-acetyl-L-phenylalanine (pAF). In some embodiments, the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 37. In some embodiments, the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 39. In some embodiments, the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 41. In some embodiments, the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 43. In some embodiments, the anti-PSMA antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 36 and a light chain amino acid sequence of SEQ ID NO: 45. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 37. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID WSGR Ref. No: 31362-826.601 NO: 36 and two light chain amino acid sequences of SEQ ID NO: 39. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 41. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 43. In some embodiments, the anti-PSMA antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 36 and two light chain amino acid sequences of SEQ ID NO: 45. In certain embodiments antibody or antibody fragments disclosed herein are anti-HER3 antibodies or antibody fragments or variants thereof. In certain embodiments, the anti-HER3 antibodies or antibody fragments or variants disclosed herein can be humanized. Anti-HER3 antibodies or antibody fragments or variants disclosed herein include, but are not limited to, anti- HER3 analogs, isoforms, mimetics, fragments, or hybrids. Anti-HER3 antibodies or antibody fragments or variants of the present disclosure include but are not limited to Fv, Fc, Fab, and (Fab')2, single chain Fv (scFv), diabodies, triabodies, tetrabodies, bifunctional hybrid antibodies, CDR1, CDR2, CDR3, combinations of CDRs, variable regions, framework regions, constant regions, heavy chains, light chains, alternative scaffold non-antibody molecules, bispecific antibodies and the like. In some other aspects of the present disclosure, there is provided an anti-HER3 antibody. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 90% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 95% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 96% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 97% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 98% identity with an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence that shares at least 99% identity with an amino acid sequence selected from the group of amino acid sequences listed in Table 5. In some embodiments, the anti-HER3 antibody has an amino acid sequence selected from the group of sequences listed in Table 5. In some embodiments, the anti-HER3 antibody comprises one or more heavy chains, wherein at least one of the one or more heavy chains has the amino acid sequence of SEQ ID NO: 58, wherein SEQ ID NO: 58 contains one non-natural amino acid at position 114 based on Kabat numbering. In some embodiments, the anti-HER3 antibody further comprise one or more WSGR Ref. No: 31362-826.601 light chains, wherein at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 or 57. In some embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 47. In some other embodiments, at least one of the one or more light chains has the amino acid sequence of SEQ ID NO: 51, wherein SEQ ID NO: 51 contains one non-natural amino acid at position 121. In some embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 58; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 47. In some embodiments, an ADC comprising the anti-HER3 antibody has a drug-to-antibody ratio of about 2. In some other embodiments, the one or more heavy chains is two heavy chains, and the amino acid sequence of each said heavy chain is the amino acid sequence of SEQ ID NO: 58; the one or more light chains is two light chains, and the amino acid sequence of each said light chain is the amino acid sequence of SEQ ID NO: 51. In some embodiments, an ADC comprising the anti-HER3 antibody has a drug-to-antibody ratio of about 3 or about 4. In some embodiments, each said non- natural amino acid is para-acetyl-L-phenylalanine (pAF). In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 47. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 48. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody WSGR Ref. No: 31362-826.601 comprises a heavy chain amino acid sequence of SEQ ID NO: 46 and a light chain amino acid sequence of SEQ ID NO: 57. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 47. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 48. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 46 and two light chain amino acid sequences of SEQ ID NO: 57. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 47. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 48. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid WSGR Ref. No: 31362-826.601 sequence of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody comprises a heavy chain amino acid sequence of SEQ ID NO: 58 and a light chain amino acid sequence of SEQ ID NO: 57. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 47. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 48. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 49. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 50. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 51. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 52. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 53. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 54. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 55. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 56. In some embodiments, the anti-HER3 antibody comprises two heavy chain amino acid sequences of SEQ ID NO: 58 and two light chain amino acid sequences of SEQ ID NO: 57. Non-limiting examples of antibodies or antibody fragments or variants of the present disclosure include the sequences listed in Tables 1 to 5. Table 1. Anti-TROP2 amino acid sequences. Also disclosed are: all of the sequences in Table 1, wherein X is replaced by any non-natural amino acid; all of the sequences in Table 1, wherein any amino acid is replaced by any non-natural amino acid; all of the sequences in Table 1, wherein X is pAF; all of the heavy chain sequences in Table 1, wherein a non-natural amino acid is site specifically WSGR Ref. No: 31362-826.601 incorporated at position 114, according to Kabat numbering, as well known to the skilled artisan; and all of the heavy chain sequences in Table 1, wherein EEM is replaced with DEL. WT: Wild Type; HC: Heavy Chain; LC: Light Chain; X denotes non-natural amino acid.
Figure imgf000081_0001
WSGR Ref. No: 31362-826.601
Figure imgf000082_0001
WSGR Ref. No: 31362-826.601
Figure imgf000083_0001
Table 2. Anti-CD70 heavy chain (HC) and light chain (LC) amino acid sequences with Amber sites for non-natural amino acid incorporation. Also disclosed are: all of the sequences in Table 2, wherein X is replaced by any non-natural amino acid; all of the sequences in Table 2, wherein any amino acid is replaced by any non-natural amino acid; all of the sequences in Table 2, wherein X is pAF; all of the heavy chain sequences in Table 2, wherein a non-natural amino acid is site specifically incorporated at position 114, according to Kabat numbering, as well known to the skilled artisan; and all of the heavy chain sequences in Table 2, wherein EEM is replaced with DEL. WT: Wild Type; HC: Heavy Chain; LC: Light Chain; X denotes non-natural amino acid. WSGR Ref. No: 31362-826.601
Figure imgf000084_0001
WSGR Ref. No: 31362-826.601
Figure imgf000085_0001
Table 3. Anti-HER2 heavy chain (HC) and light chain (LC) amino acid sequences with amber sites for non-natural amino acid incorporation. Also disclosed are: all of the sequences in Table 3, wherein X is replaced by any non-natural amino acid; all of the sequences in Table 3, wherein any amino acid is replaced by any non-natural amino acid; all of the sequences in Table 3, wherein X is pAF; all of the heavy chain sequences in Table 3, wherein a non-natural amino acid is site specifically incorporated at position 114, according to Kabat numbering, as well known to the skilled artisan; and all of the heavy chain sequences of Table 3, wherein DEL is replaced with EEM. WT: Wild Type; HC: Heavy Chain; LC: Light Chain; X denotes non-natural amino acid.
Figure imgf000085_0002
WSGR Ref. No: 31362-826.601
Figure imgf000086_0001
Table 4. Anti-PSMA heavy chain (HC) and light chain (LC) amino acid sequences with amber sites for non-natural amino acid incorporation. Also disclosed are: all of the sequences in Table 4, wherein any amino acid is replaced by any non-natural amino acid; all of the sequences in Table 4, wherein X is pAF; all of the heavy chain sequences in Table 4, wherein a non-natural amino acid is site specifically incorporated at position 114, according to Kabat numbering, as well known to the skilled WSGR Ref. No: 31362-826.601 artisan; and all of the heavy chain sequences of Table 4, wherein DEL is replaced with EEM. WT: Wild Type; HC: Heavy Chain; LC: Light Chain; X denotes non-natural amino acid.
Figure imgf000087_0001
WSGR Ref. No: 31362-826.601
Figure imgf000088_0001
WSGR Ref. No: 31362-826.601
Figure imgf000089_0001
Table 5. Anti-HER3 heavy chain (HC) and light chain (LC) amino acid sequences with amber sites for non-natural amino acid incorporation. Also disclosed are: all of the sequences in Table 5, wherein any amino acid is replaced by any non-natural amino acid; all of the sequences in Table 5, wherein X is pAF; all of the heavy chain sequences in Table 5, wherein a non-natural amino acid is site specifically incorporated at position 114, according to Kabat numbering, as well known to the skilled artisan; and all of the heavy chain sequences of Table 5, wherein EEM is replaced with DEL. WT: Wild Type; HC: Heavy Chain; LC: Light Chain; X denotes non-natural amino acid. WSGR Ref. No: 31362-826.601
Figure imgf000090_0001
WSGR Ref. No: 31362-826.601
Figure imgf000091_0001
Non-Natural Amino Acids The present disclosure provides antibodies, antibody fragments or variants comprising at least one non-natural amino acid. Introduction of at least one non-natural amino acid into an antibody can WSGR Ref. No: 31362-826.601 allow for the application of conjugation chemistries that involve specific chemical reactions with one or more non-natural amino acids while not reacting with the commonly occurring 20 amino acids. Non-natural amino acid site selection was based on surface exposure/site accessibility within the antibody and hydrophobic or neutral amino acid sites were selected to maintain the charge on the antibody. Methods for introducing non-natural amino acids inserted into sites in a protein are described for example in WO2010/011735 and in WO2005/074650. The present disclosure employs such methodologies and techniques. The non-natural amino acids used in the methods and compositions described herein have at least one of the following four properties: (1) at least one functional group on the sidechain of the non-natural amino acid has at least one characteristics and/or activity and/or reactivity orthogonal to the chemical reactivity of the 20 common, genetically- encoded amino acids (i.e., alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine), or at least orthogonal to the chemical reactivity of the naturally occurring amino acids present in the polypeptide that includes the non-natural amino acid; (2) the introduced non-natural amino acids are substantially chemically inert toward the 20 common, genetically-encoded amino acids; (3) the non-natural amino acid can be stably incorporated into a polypeptide, preferably with the stability commensurate with the naturally-occurring amino acids or under typical physiological conditions, and further preferably such incorporation can occur via an in vivo system; and (4) the non-natural amino acid includes an oxime functional group or a functional group that can be transformed into an oxime group by reacting with a reagent, preferably under conditions that do not destroy the biological properties of the polypeptide that includes the non- natural amino acid (unless of course such a destruction of biological properties is the purpose of the modification/transformation), or where the transformation can occur under aqueous conditions at a pH between about 4 and about 8, or where the reactive site on the non-natural amino acid is an electrophilic site. Any number of non-natural amino acids can be introduced into the polypeptide. Non-natural amino acids may also include protected or masked oximes or protected or masked groups that can be transformed into an oxime group after deprotection of the protected group or unmasking of the masked group. Non-natural amino acids may also include protected or masked carbonyl or dicarbonyl groups, which can be transformed into a carbonyl or dicarbonyl group after deprotection of the protected group or unmasking of the masked group and thereby are available to react with hydroxylamines or oximes to form oxime groups. Oxime-based non-natural amino acids may be synthesized by methods well known in the art, (see for example WO2013/185117 and WO2005/074650), including: (a) reaction of a hydroxylamine-containing non-natural amino acid with a carbonyl- or dicarbonyl-containing reagent; (b) reaction of a carbonyl- or dicarbonyl- WSGR Ref. No: 31362-826.601 containing non-natural amino acid with a hydroxylamine-containing reagent; or (c) reaction of an oxime-containing non-natural amino acid with certain carbonyl- or dicarbonyl-containing reagents. In some embodiments, non-naturally encoded amino acid site selection is based on surface exposure. Example, one possible site is an amino acid having a solvent accessible surface area ratio of 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more. In some embodiments, one possible site is an amino acid having a solvent accessible surface area ratio of about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 95%, or more. The solvent accessible surface area can be calculated based on the DSSP program [Biopolymers, 22, 2577-2637 (1983)], using a crystalline structure analyzing data file of antibodies or antibody fragments registered in Protein data bank (PDB). The ratio of the solvent accessible surface area of the amino acid residues of interest can be calculated by dividing the antibody structural solvent accessible surface area calculated in the above by the solvent accessible surface area of alanine-X-alanine (X represents the amino acid residues of interest). In this connection, there is a case in which two or more PDB files are present on one species of protein, and any one of them can be used in the present invention. Alternatively, the solvent accessibility of an amino acid can be determined by a solvent accessibility test in which a functional group on the amino acid (a thiol, amino, or carbonyl group) is functionalized when treated with an electrophilic reagent or a nucleophilic reagent, or the like. Based on the test results, the functional group (i.e., the thiol, amino, or carbonyl group) can be called, for example, at least 50% solvent accessible when at least 50% of the functional group is functionalized in the test. In some embodiments, the non-natural amino acid site is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95% solvent accessible. Examples of solvent accessibility test include, but are not limited to, Non-natural amino acids that may be used in the methods and compositions described herein include, but are not limited to, amino acids comprising amino acids with novel functional groups, amino acids that covalently or noncovalently interact with other molecules, glycosylated amino acids such as a sugar substituted serine, other carbohydrate modified amino acids, keto-containing amino acids, aldehyde-containing amino acids, amino acids comprising polyethylene glycol or other polyethers, heavy atom substituted amino acids, chemically cleavable and/or photocleavable amino acids, amino acids with an elongated side chains as compared to natural amino acids, including but not limited to, polyethers or long chain hydrocarbons, including but not limited to, greater than about 5 or greater than about 10 carbons, carbon-linked sugar-containing amino acids, redox-active amino acids, amino thioacid containing amino acids, and amino acids comprising one or more toxic moiety. WSGR Ref. No: 31362-826.601 In some embodiments disclosed herein are antibodies comprising one or more non-natural amino acids. The one or more non-natural amino acids may be encoded by a codon that does not code for one of the twenty natural amino acids. The one or more non-natural amino acids may be encoded by a nonsense codon (stop codon). The stop codon may be an amber codon. The amber codon may comprise a UAG sequence. The stop codon may be an ochre codon. The ochre codon may comprise a UAA sequence. The stop codon may be an opal or umber codon. The opal or umber codon may comprise a UGA sequence. The one or more non-natural amino acids may be encoded by a four-base codon. Non-natural amino acids of the present disclosure include, but are not limited to, 1) substituted phenylalanine and tyrosine analogues, such as 4-amino-L-phenylalanine, 4-acetyl-L-phenylalanine, 4-azido-L-phenylalanine, 4-nitro-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-isopropyl-L- phenylalanine, 3-nitro-L-tyrosine, O-methyl-L-tyrosine and O-phosphotyrosine; 2) amino acids that can be photo-cross-linked, e.g., amino acids with aryl azide or benzophenone groups, such as 4- azidophenylalanine or 4-benzoylphenylalanine; 3) amino acids that have unique chemical reactivity, such as 4-acetyl-L-phenylalanine, 3-acetyl-L-phenylalanine, O-allyl-L-tyrosine, O-2-propyn-1-yl-L- tyrosine, N-(ethylthio)thiocarbonyl-L-phenylalanine and p-(3-oxobutanoyl)-L-phenylalanine; 4) heavy-atom-containing amino acids, e.g., for phasing in X-ray crystallography, such as 4-iodo-L- phenylalanine or 4-bromo-L-phenylalanine; 5) a redox-active amino acid, such as 3,4-dihydroxy-L- phenylalanine; 6) a fluorinated amino acid, such as a 2-fluorophenylalanine (e.g., 2-fluoro-L- phenylalanine), a 3-fluorophenylalanine (e.g., 3-fluoro-L-phenylalanine) or a 4-fluorophenylalanine (e.g., 4-fluoro-L-phenylalanine; 7) a fluorescent amino acid, such as an amino acid containing a naphthyl, dansyl or 7-aminocoumarin side chain; 8) a photocleavable or photoisomerizable amino acid, such as an amino acid comprising an azobenzyl or nitrobenzyl, e.g., cysteine, serine or tyrosine 2 3 amino acid); 10) a homo- amino acid, such as homoglutamine (e.g., beta-homoglutamine) or homophenylalanine (e.g., beta- homophenylalanine); 11) a proline or pyruvic acid derivative; 12) a 3-substituted alanine derivative; 14) a glycine derivative; 15) a linear core amino acid; 16) a diamino acid; 17) a D-amino acid; 18) an N-methyl amino acid; 19) a phosphotyrosine mimetic, such as a carboxymethylphenylalanine (pCmF) (e.g., 4-carboxymethyl-L-phenylalanine); 20) 2-aminooctanoic acid; and 21) an amino acid comprising a saccharide moiety, such as N-acetyl-L-glucosaminyl-L-serine, beta-N- acetylglucosamine-O-serine, N-acetyl-L-galactosaminyl-L-serine, alpha-N-acetylgalactosamine-O- serine, O-(3-O-D-galactosyl-N-acetyl-beta-D-galactosaminyl)-L-serine, N-acetyl-L-glucosaminyl- L-threonine, alpha-N-acetylgalactosamine-O-threonine, 3-O-(N-acetyl-beta-D-glucosaminyl)-L- WSGR Ref. No: 31362-826.601 and O-(mannosyl)-L-serine; an amino acid wherein the naturally-occurring N- or O- linkage between the amino acid and the saccharide is replaced by a covalent linkage not commonly found in nature, including but not limited to, an alkene, an oxime, a thioether, an amide and the like; or an amino acid containing saccharides that are not commonly found in naturally-occurring polypeptides, such as 2- deoxy-glucose, 2-deoxy-galactose and the like. Specific examples of non-natural amino acids include, but are not limited to, a p-acetylphenylalanine (4-acetyl phenylalanine) (including 4-acetyl-L- phenylalanine, also referred to herein as p-acetyl-L-phenylalanine (pAF)), a 4-boronophenylalanine (pBoF) (e.g., 4-borono-L-phenylalanine, a 4-propargyloxyphenylalanine (pPrF) (e.g., 4- propargyloxy-L-phenylalanine), an O-methyltyrosine (e.g., O-methyl-L-tyrosine), a 3-(2- naphthyl)alanine (NapA) (e.g., 3-(2-naphthyl)-L-alanine), a 3-methylphenylalanine (e.g., 3-methyl- L-phenylalanine), an O-allyltyrosine (e.g., O-allyl-L-tyrosine), an O-isopropyltyrosine (e.g., O- isopropyl-L-tyrosine), a dopamine (e.g., L-Dopa), a 4-isopropylphenylalanine (e.g., 4-isopropyl-L- phenylalanine), a 4-azidophenylalanine (pAz) (e.g., 4-azido-L-phenylalanine), a 4- benzoylphenylalanine (pBpF) (e.g., 4-benzoyl-L-phenylalanine), an O-phosphoserine (e.g., O- phospho-L-serine), an O-phosphotyrosine (e.g., O-phospho-L-tyrosine), a 4-iodophenylalanine (pIF) (e.g., 4-iodo-L-phenylalanine, a 4-bromophenylalanine (e.g., 4-bromo-L-phenylalanine), a 4- aminophenylalanine (e.g., 4-amino-L-phenylalanine), a 4-cyanophenylalanine (pCNF) (e.g., 4- cyano-L-phenylalanine, a (8-hydroxyquinolin-3-yl)alanine (HQA) (e.g., (8-hydroxyquinolin-3-yl)- L-alanine), a (2,2-bipyridin-5-yl)alanine (BipyA) (e.g., (2,2-bipyridin-5-yl)-L-alanine), and the like. Additional non-natural amino acids are disclosed in Liu et al. (2010) Annu Rev Biochem, 79:413-44; Wang et al. (2005) Angew Chem Int Ed, 44:34-66; and Published International Application Nos.: WO 2012/166560, WO 2012/166559, WO 2011/028195, WO 2010/037062, WO 2008/083346, WO 2008/077079, WO 2007/094916, WO 2007/079130, WO 2007/070659 and WO 2007/059312, the entire contents of each of which are hereby incorporated by reference herein in their entirety. In some embodiments, the one or more non-natural amino acids can be p- acetylphenylalanine. In some more particular embodiments, the one or more non-natural amino acids can be p-acetyl-L-phenylalanine (pAF). In some embodiments, one or more non-natural amino acids is selected from the group Acetyl-D-glucosaminyl)asparagine, O-allyltyrosine, alpha-N-acetylgalactosamine-O-serine, alpha- N-acetylgalactosamine-O-threonine, 2-aminooctanoic acid, 2-aminophenylalanine, 3- aminophenylalanine, 4-aminophenylalanine, 2-aminotyrosine, 3-aminotyrosine, 4- azidophenylalanine, 4-benzoylphenylalanine, (2,2-bipyridin-5yl)alanine, 3-boronophenylalanine, 4- boronophenylalanine, 4-bromophenylalanine, p-carboxymethylphenylalanine, 4- WSGR Ref. No: 31362-826.601 carboxyphenylalanine, p-cyanophenylalanine, 3,4-dihydroxyphenylalanine, 4-ethynylphenylalanine, 2-fluorophenylalanine, 3-fluorophenylalanine, 4-fluorophenylalanine, O-(3-O-D-galactosyl-N- acetyl-beta-D-galactosaminyl)serine, homoglutamine, (8-hydroxyquinolin-3-yl)alanine, 4- iodophenylalanine, 4-isopropylphenylalanine, O-i-propyltyrosine, 3-isopropyltyrosine, O- mannopyranosylserine, 2-methoxyphenylalanine, 3-methoxyphenylalanine, 4- methoxyphenylalanine, 3-methylphenylalanine, O-methyltyrosine, 3-(2-naphthyl)alanine, 5- nitrohistidine, 4-nitrohistidine, 4-nitroleucine, 2-nitrophenylalanine, 3-nitrophenylalanine, 4- nitrophenylalanine, 4-nitrotryptophan, 5-nitrotryptophan, 6-nitrotryptophan, 7-nitrotryptophan, 2- nitrotyrosine, 3-nitrotyrosine, O-phosphoserine, O-phosphotyrosine, 4-propargyloxyphenylalanine, O-2-propyn-1-yltyrosine, 4-sulfophenylalanine and O-sulfotyrosine. In some further embodiments, one or more non-natural amino acids is selected from the group consisting of 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)), 3-O-(N-acetyl-beta-D- alpha-N-acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2- aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L-tyrosine, 3-amino-L-tyrosine, 4-azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin-5yl)-L-alanine, 3-borono-L-phenylalanine, 4-borono-L-phenylalanine, 4-bromo-L- phenylalanine, p-carboxymethyl-L-phenylalanine, 4-carboxy-L-phenylalanine, p-cyano-L- phenylalanine, 3,4-dihydroxy-L-phenylalanine (L-DOPA), 4-ethynyl-L-phenylalanine, 2-fluoro-L- phenylalanine, 3-fluoro-L-phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl- beta-D-galactosaminyl)-L-serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L- phenylalanine, 4-isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O- mannopyranosyl-L-serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L- phenylalanine, 3-methyl-L-phenylalanine, O-methyl-L-tyrosine, 3-(2-naphthyl)-L-alanine, 5-nitro- L-histidine, 4-nitro-L-histidine, 4-nitro-L-leucine, 2-nitro-L-phenylalanine, 3-nitro-L-phenylalanine, 4-nitro-L-phenylalanine, 4-nitro-L-tryptophan, 5-nitro-L-tryptophan, 6-nitro-L-tryptophan, 7-nitro- L-tryptophan, 2-nitro-L-tyrosine, 3-nitro-L-tyrosine, O-phospho-L-serine, O-phospho-L-tyrosine, 4- propargyloxy-L-phenylalanine, O-2-propyn-1-yl-L-tyrosine, 4-sulfo-L-phenylalanine and O-sulfo- L-tyrosine. In some embodiments, the one or more non-natural amino acids can be p-acetyl-L- phenylalanine (pAF). Thus, in some embodiments, each and every one of the one or more non- natural amino acids is pAF. In certain embodiments of the disclosure, an antibody with at least one non-natural amino acid includes at least one post-translational modification. In one embodiment, the at least one post- translational modification comprises attachment of a molecule including but not limited to, a water- WSGR Ref. No: 31362-826.601 soluble polymer, a derivative of polyethylene glycol, a drug, a second protein or polypeptide or polypeptide analog, an antibody or antibody fragment, a biologically active agent, a small molecule, or any combination of the above or any other desirable compound or substance, comprising a second reactive group to at least one non-natural amino acid comprising a first reactive group utilizing chemistry methodology that is known to one of ordinary skill in the art to be suitable for the particular reactive groups. For example, the first reactive group is an alkynyl moiety (including but not limited to, the non-natural amino acid p-propargyloxyphenylalanine, where the propargyl group is also sometimes referred to as an acetylene moiety) and the second reactive group is an azido moiety, and [3+2] cycloaddition chemistry methodologies are utilized. In another example, the first reactive group is the azido moiety (including but not limited to, the non-natural amino acid p-azido-L- phenylalanine) and the second reactive group is the alkynyl moiety. In certain embodiments of the modified antibody polypeptide of the present disclosure at least one non-natural amino acid, (including but not limited to, non-natural amino acid containing a keto functional group), comprising at least one post-translational modification is used where the at least one post-translational modification comprises a saccharide moiety. In certain embodiments, the post-translational modification is made in vivo in a eukaryotic cell or in a non-eukaryotic cell. In other embodiments the post-translational modification is made in vitro. In another embodiment, the post-translational modification is made in vitro and in vivo. In some embodiments, the non-natural amino acid may be modified to incorporate a chemical group. In some embodiments the non-natural amino acid may be modified to incorporate a ketone group. The one or more non-natural amino acids may comprise at least one oxime, carbonyl, dicarbonyl, hydroxylamine group or a combination thereof. The one or more non-natural amino acids may comprise at least one carbonyl, dicarbonyl, alkoxy-amine, hydrazine, acyclic alkene, acyclic alkyne, cyclooctyne, aryl/alkyl azide, norbornene, cyclopropene, trans-cyclooctene, or tetrazine functional group or a combination thereof. In some embodiments disclosed herein the non-natural amino acid is site-specifically incorporated into the antibody, antibody fragment or variant. In some embodiments the non-natural amino acid is site-specifically incorporated into an antibody, antibody fragment or variant. Methods for incorporating a non-natural amino acid into a molecule, for example, proteins, polypeptides or peptides, are disclosed in U.S. Patent Nos.: 7,332,571; 7,928,163; 7,696,312; 8,008,456; 8,048,988; 8,809,511; 8,859,802; 8,791,231; 8,476,411; or 9,637,411, (each of which is incorporated herein by reference in its entirety), and in the Examples herein. The one or more non-natural amino acids may be incorporated by methods known in the art. For example, cell-based or cell-free systems may be used, and auxotrophic strains may also be used in place of engineered tRNA and synthetase. In certain WSGR Ref. No: 31362-826.601 embodiments, orthogonal tRNA synthetase are used as disclosed in for example, WO2002085923A2; WO2002086075A2; WO2004035743A2; WO2007021297A1; WO2006068802A2; and WO2006069246A2; the contents of each of which are incorporated herein by reference in their entirety. Incorporating one or more non-natural amino acids into the antibody or antibody fragment or variant may comprise modifying one or more amino acid residues in the antibody or antibody fragment or variant. Modifying the one or more amino acid residues in the antibody or antibody fragment or variant may comprise mutating one or more nucleotides in the nucleotide sequence encoding the antibody or antibody fragment or variant. Mutating the one or more nucleotides in the nucleotide sequence encoding the antibody or antibody fragment or variant may comprise altering a codon encoding an amino acid to a nonsense codon. Incorporating one or more non-natural amino acids into the antibody or antibody fragment or variant may comprise modifying one or more amino acid residues in the antibody or antibody fragment or variant to produce one or more amber codons in the antibody or antibody fragment or variant. The one or more non-natural amino acids may be incorporated into the antibody or antibody fragment or variant in response to an amber codon. The one or more non-natural amino acids may be site-specifically incorporated into the antibody or antibody fragment or variant. Incorporating one or more non-natural amino acids into the antibody or antibody fragment or variant may comprise one or more genetically encoded non-natural amino acids with orthogonal chemical reactivity relative to the canonical twenty amino acids to site- specifically modify the biologically active molecule or targeting agent. As understood by a person of ordinary skill in the art, the twenty canonical amino acids are alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine. Incorporating the one or more non-natural amino acids may comprise use of a tRNA/aminoacyl-tRNA synthetase pair to site- specifically incorporate one or more non-natural amino acids at defined sites in the biologically active molecule or targeting agent in response to one or more amber nonsense codon. Additional methods for incorporating non-natural amino acids include, but are not limited to, methods disclosed in Chatterjee et al., A Versatile Platform for Single- and Multiple-Unnatural Amino Acid Mutagenesis in Escherichia coli, Biochemistry, 2013; Kazane et al., J Am Chem Soc, 135(1):340-6, 2013; Kim et al., J Am Chem Soc, 134(24):9918-21, 2012; Johnson et al., Nat Chem Biol, 7(11):779-86, 2011; and Hutchins et al., J Mol Biol, 406(4):595-603, 2011. The one or more non-natural amino acids may be produced through selective reaction of one or more natural amino acids. The selective reaction may be mediated by one or more enzymes. In non-limiting examples, the selective reaction of one or more cysteines with formylglycine generating enzyme (FGE) may produce one or more formylglycines as described in Rabuka et al., Nature Protocols 7: 1052-1067, 2012. The one or more non-natural amino WSGR Ref. No: 31362-826.601 acids may involve a chemical reaction to form a linker. The chemical reaction to form the linker may include a bioorthogonal reaction. The chemical reaction to form the linker may include click chemistry. See for example WO2006/050262 incorporated herein by reference in its entirety. Any position of the antibody or antibody fragment is suitable for selection to incorporate a non-natural amino acid, and selection may be based on rational design or by random selection for any or no particular desired purpose. Selection of desired sites may be based on producing a non- natural amino acid polypeptide (which may be further modified or remain unmodified) having any desired property or activity, including but not limited to a receptor binding modulators, receptor activity modulators, modulators of binding to binder partners, binding partner activity modulators, binding partner conformation modulators, dimer or multimer formation, no change to activity or property compared to the native molecule, or manipulating any physical or chemical property of the polypeptide such as solubility, aggregation, or stability. Alternatively, the sites identified as critical to biological activity may also be good candidates for substitution with a non-natural amino acid, again depending on the desired activity sought for the polypeptide. Another alternative would be to simply make serial substitutions in each position on the polypeptide chain with a non-natural amino acid and observe the effect on the activities of the polypeptide. Any means, technique, or method for selecting a position for substitution with a non-natural amino acid into any polypeptide is suitable for use in the methods, techniques and compositions described herein. The structure and activity of naturally-occurring mutants of a polypeptide that contain deletions can also be examined to determine regions of the protein that are likely to be tolerant of substitution with a non-natural amino acid. Once residues that are likely to be intolerant to substitution with non-natural amino acids have been eliminated, the impact of proposed substitutions at each of the remaining positions can be examined using methods including, but not limited to, the three-dimensional structure of the relevant polypeptide, and any associated ligands or binding proteins. X-ray crystallographic and NMR structures of many polypeptides are available in the Protein Data Bank (PDB, see world wide web for rcsb.org), a centralized database containing three- dimensional structural data of large molecules of proteins and nucleic acids, and can be used to identify amino acid positions that can be substituted with non-natural amino acids. In addition, models may be made investigating the secondary and tertiary structure of polypeptides, if three- dimensional structural data is not available. Thus, the identity of amino acid positions that can be substituted with non-natural amino acids can be determined by the skilled person. Exemplary sites of incorporation of a non-natural amino acid include, but are not limited to, those that are excluded from potential receptor binding regions, or regions for binding to binding proteins or ligands may be fully or partially solvent exposed, have minimal or no hydrogen-bonding WSGR Ref. No: 31362-826.601 interactions with nearby residues, may be minimally exposed to nearby reactive residues, and/or may be in regions that are highly flexible as predicted by the three-dimensional crystal structure of a particular polypeptide with its associated receptor, ligand or binding proteins A wide variety of non-natural amino acids can be substituted for, or incorporated into, a given position in a polypeptide. By way of example, a particular non-natural amino acid may be selected for incorporation based on an examination of the three-dimensional crystal structure of a polypeptide with its associated ligand, receptor and/or binding proteins, a preference for conservative substitutions. Linkers In some aspects, the present disclosure relates to linkers for intracellular delivery of drug conjugates. Many procedures and linker molecules for attachment of various compounds to peptides are known. See, for example, European Patent Application No.0188256; U.S. Patent Nos.4,671,958, 4,659,839, 4,414,148, 4,699,784, 4,680,338, 4,569,789 and 10,550,190; PCT Application Publication Nos. WO 2012/166559 A1, WO 2012/166560 A1, WO 2013/185117 A1, WO 2013/192360 A1 and WO 2022/040596 A1; and US Patent Application Publication No. US 2017/0182181 A1; the contents of each of which are hereby incorporated by reference in their entirety. In some embodiments, the present disclosure relates to phosphate-based linkers for intracellular delivery of drug conjugates (see, e.g., U.S. patent no.10,550,190). The phosphate-based linkers of the present disclosure include a monophosphate, diphosphate, triphosphate, or tetraphosphate group (phosphate group) and a linker arm and optionally a spacer. A drug-linker can be covalently linked to a reactive functional group that can be covalently linked to a cell-specific targeting ligand such as an antibody or antibody fragment. Phosphate-based linkers have a differentiated and tunable stability in blood compared to the intracellular environment (e.g. lysosomal compartment). Thus, ADCs comprising these phosphate-based linkers are stable in circulation (plasma/blood) but reactive or cleavable in intracellular compartments (lysosome) making them useful for intracellular delivery of drug conjugates. The phosphate-based linker is capable of being conjugated to a drug and the reactive functional group is capable of being conjugated to a cell-specific targeting ligand such as an anti-TROP2 antibody, an anti-HER2 antibody, an anti-CD70 antibody, an anti-HER3 antibody or an anti-PSMA antibody. The phosphate-based linkers of the present disclosure are designed to engineer ADCs such that the likelihood of the conjugate to form aggregates is reduced compared to conjugates in which the same drug is conjugated to the antibody or targeting ligand using a linker that is not a phosphate-based linker. Further, the phosphate-based linker design, WSGR Ref. No: 31362-826.601 stability, pH, redox sensitivities and protease susceptibility influence circulatory stability and release of the drug. Methods for selecting and designing linkers are well known in the art. Linkers may be designed de novo, including by way of example only, as part of high-throughput screening process (in which case numerous polypeptides may be designed, synthesized, characterized and/or tested) or based on the interests of the researcher. The linker may also be designed based on the structure of a known or partially characterized polypeptide. The principles for selecting which amino acid(s) to substitute and/or modify and the choice of which modification to employ are described in WO2013/185117, for example. Linkers may be designed to meet the needs of the experimenter or end user. Such needs may include, but are not limited to, manipulating the therapeutic effectiveness of the polypeptide, improving the safety profile of the polypeptide, adjusting the pharmacokinetics, pharmacologics and/or pharmacodynamics of the polypeptide, such as, by way of example only, increasing water solubility, bioavailability, increasing serum half-life, increasing therapeutic half- life, modulating immunogenicity, modulating biological activity, or extending the circulation time. In addition, such modifications include, by way of example only, providing additional functionality to the polypeptide, incorporating an antibody, and any combination of the aforementioned modifications. Generally, a linker of the present disclosure can be a unit that is combinable with one or more additional units, such that the combined linker units can bond to one or more drugs. Each linker unit can be comprised of one or more moieties, each of which may occur one or more times. In some embodiments, a linker of the present disclosure comprises at least one phosphate- based moiety, as disclosed herein. In some embodiments, the linker comprises the phosphate-based moiety and further comprises at least one moiety or unit that is not phosphate-based. In some embodiments, the linker is a bivalent linker. In some embodiments, the linker is a trivalent linker. In some embodiments, the linker is a tetravalent linker. Thus, in some aspects, the present disclosure provides for phosphate-based linkers. A phosphate-based linker of the present disclosure can comprise a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate and/or a diphosphorthioate. Thus, a phosphate-based linker of the present disclosure can comprise:
Figure imgf000101_0001
a phosphate ester having the structure ; WSGR Ref. No: 31362-826.601 a phosphonate having the structure
Figure imgf000102_0001
Figure imgf000102_0002
a pyrophosphate ester having the structure ; a diphosphonate having the structure
Figure imgf000102_0003
a triphosphate ester having the structure
Figure imgf000102_0004
;
Figure imgf000102_0005
a tetraphosphate ester having the structure ;
Figure imgf000102_0006
a phosphorthioate having the structure ; a diphosphorthioate having the structure
Figure imgf000102_0007
a phosphoramidate having the structure
Figure imgf000102_0008
Figure imgf000102_0009
a triphosphoramidate having the structure
Figure imgf000102_0010
a tetraphosphoramidate having the structure
Figure imgf000102_0011
. WSGR Ref. No: 31362-826.601 In some embodiments, a phosphate-based linker of the present disclosure is chiral. In some embodiments, a phosphate-based linker of the present disclosure comprises a phosphate-based moiety selected from the group consisting of a pyrophosphate ester and a diphosphonate. In some embodiment, a phosphate-based linker of the present disclosure can be synthesis according to Schemes A and B below. In Scheme A, two monophosphate analogues react with each other under a coupling reaction condition to make the pyrophosphate analogues bearing a reactive group (RG). RG then can be used to react with L2- or L3-L2-containing reagents leading to compounds of Formula (I), wherein L2 and L3 are as defined according to Formula (I) disclosed herein. Or RG is an L2 or L3-L2-containing groups that can react with an antibody; wherein L2 and L3 are as defined according to Formula (I) disclosed herein. Scheme A: Reactions routes relying on a coupling reaction to make pyrophosphate analogs
Figure imgf000103_0001
In scheme B, phosphite or phosphite analogs are sulfurized by sulfurization reagents (xanthane hydride, phenylacetyl disulphide or Beaucage reagent) to introduce the P=S functionality. Scheme B: WSGR Ref. No: 31362-826.601
Figure imgf000104_0001
Figure imgf000104_0002
Figure imgf000104_0003
Figure imgf000104_0004
In some embodiments, a phosphate-based linker of the present disclosure further comprises at least one additional moiety. In some embodiments, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, – (alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, each arylene is phenylene. In some more particular embodiments, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and - N(Rw)-, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, each Rw is independently H or methyl. In some embodiments, a phosphate-based linker of the present disclosure consists of a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(Rw)- and an amino acid; wherein each nn is independently an integer from 1 to 100; WSGR Ref. No: 31362-826.601 wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, each Rw is independently H or methyl. In some embodiments, a phosphate-based linker of the present disclosure is a linker selected from the group of linkers listed in Table 6. Table 6. Non-limiting examples of linkers of the present disclosure.
Figure imgf000105_0001
WSGR Ref. No: 31362-826.601
Figure imgf000106_0001
WSGR Ref. No: 31362-826.601
Figure imgf000107_0001
In some embodiments, each alkylene of Table 6 is independently –(CH2)–, –(CH2)2– or – (CH2)3–. In some embodiments, each nn of Table 6 is independently 1, 2 or 3. In some embodiments, each i of Table 6 is 1. In some other embodiments, each i of Table 6 is 0. In some embodiments, a phosphate-based linker of the present disclosure is a linker selected from the group of linkers listed in Table 7. Table 7. Non-limiting examples of linkers of the present disclosure.
Figure imgf000107_0002
WSGR Ref. No: 31362-826.601
Figure imgf000108_0001
In some embodiments, each alkylene of Table 7 is independently –(CH2)–, –(CH2)2– or – (CH2)3–. In some embodiments, each n of Table 7 is independently 1, 2 or 3. In some embodiments, each i of Table 7 is 1. WSGR Ref. No: 31362-826.601 In some other embodiments, each i of Table 7 is 0. In some embodiments, a phosphate-based linker of the present disclosure is a linker selected from the group of linkers listed in Table 8. Table 8. Non-limiting examples of linkers of the present disclosure.
Figure imgf000109_0001
In some embodiments, each alkylene of Table 8 is independently –(CH2)–, –(CH2)2– or – (CH2)3–. In some embodiments, each n of Table 8 is independently 1, 2 or 3. In some embodiments, each i of Table 8 is 0. In some other embodiments, each i of Table 8 is 1. WSGR Ref. No: 31362-826.601 In some embodiments, the phosphate-based linker is *–C(O)-O-alkylene-O-P(=O)(OH)-O- P(=O)(OH)-(O)i-alkylene–. In some embodiments, i is 1. In some embodiments, *– C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene– has the following structure: *–C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)-(CH2CH2)–. In some other embodiments, the phosphate-based linker is: *–alkylene-O-P(=O)(OH)-O- P(=O)(OH)-(O)i-alkylene–. In some embodiments, i is 1. In some embodiments, *– alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene– has the following structure: *–(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)-(CH2CH2)–. It is understood that, unless expressly indicated otherwise, no orientation of a linker is implied by the direction in which the formula of the linker group is written. By way of example, the formula –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i– listed in Table 6 represents both –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i– and –(O)i-P(=O)(OH)-O-P(=O)(OH)-O-alkylene–. In another example, the formula –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i– listed in Table 6 represents both *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i– and –alkylene-O-P(=O)(OH)-O- P(=O)(OH)-(O)i–*, wherein * denotes a point of connection, for example, connection to a drug. It is further understood that, when each alkylene (or other variable) of a linker is independently selected from a group of variables, the independent selection can be made within a given linker. By way of example only, the formula *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i- alkylene–(O-alkylene)nn–, wherein each nn is independently an integer from 1 to 100; wherein each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–, includes but is not limited to the following species: *–(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(CH2)2-(O-(CH2)3)nn–, *–(CH2)2-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(CH2)3-(O-CH2)nn–, *–(CH2)2-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(CH2)2-(O-(CH2)2)nn–, *–(CH2)3-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(CH2)-(O-(CH2)2)nn– and *–(CH2)2-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(CH2)-(O-(CH2)2)nn–. Furthermore, by way of example only, the group *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)- (O)i-alkylene–(O-alkylene)nn–, wherein each alkylene is independently –(CH2)–, –(CH2)2– or – (CH2)3–, can be rewritten: *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i nn– 2)–, –(CH2)2– or –(CH2)3–. Similarly, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-J-alkylene-(alkylene– O)nn–, wherein each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–, and each n is independently 1, 2 or 3, can be rewritten: *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i- WSGR Ref. No: 31362-826.601 2)–, –(CH2)2– or –(CH2)3 1, 2 or 3. In some embodiments, the linker is *–C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)- (CH2CH2)–. In some embodiments, the linker *–C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)- (CH2CH2)– has the following structure:
Figure imgf000111_0001
wherein: n is an integer from 1 to 10; q is an integer from 1 to 10; i is 0 or 1; * denotes the connection to drug; and + denotes connection to a reactive moiety. In some embodiments, i is 1. In some embodiments, q is 1. In some embodiments, n is 2. In some other embodiments, the linker is *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)- (O-alkylene)nn–, wherein each n is independently an integer of from 1 to 100. In some embodiments, the linker *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn– has the following structure:
Figure imgf000111_0002
wherein: m is an integer from 1 to 10; n is an integer from 1 to 10; q is an integer from 1 to 10; i is 0 or 1; * denotes the connection to drug; and + denotes connection to a reactive moiety. In some embodiments, i is 1. In some embodiments, n is 2. In some embodiments, m is 1, 2 or 3. In some embodiments, a phosphate-based linker of the present disclosure is selected from the group consisting of: WSGR Ref. No: 31362-826.601
Figure imgf000112_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to drug; and each + denotes connection to a reactive moiety. In some further embodiments, each m is independently 1, 2 or 3; each n independently 1, 2 or 3; and each q is independently 1, 2 or 3. In some embodiments, i is 1. In other embodiments, i is 0. In some embodiments, when the atom or moiety of a linker that is connected to drug is carbonyl (C(O)), then the linker is joined to a nitrogen atom of the drug (e.g., the nitrogen of an amino or substituted amine group). In some embodiments, L is *-C(O)-O-CH2-O-P(=O)(OH)-O- P(=O)(OH)-O-CH2CH2-+. WSGR Ref. No: 31362-826.601 In some embodiments, L is *-CH2-O-P(=O)(OH)-O-P(=O)(OH)-O-CH2CH2-+. In some embodiments, L is joined to a bivalent oxygen atom of the drug (e.g., the oxygen of a hydroxyl group). In some embodiments, a phosphate-based linker of the present disclosure is connected to a drug and is also connected to a reactive moiety. Thus, the linker bridges the drug and the reactive moiety. The reactive moiety can be one that can react with another moiety of a natural amino acid or non-natural amino acid of a polypeptide, such as an antibody, antibody fragment or variant thereof of the present disclosure, as disclosed herein. In some other embodiments, a phosphate-based linker as disclosed herein is connected to a drug, and is also connected to an antibody, antibody fragment or variant thereof, via a linkage or adduct moiety. Thus, the linker bridges the drug and the antibody, antibody fragment or variant thereof. Drugs and Drug-Linkers In some aspects, the present disclosure provides a drug or drug-linker, wherein the drug is a cytotoxic drug or agent. In some aspects of the disclosure, the cytotoxic drug is exatecan, an exatecan derivative or exatecan analog. In some embodiments the drug or drug-linker is a drug or drug-linker generated as described in the Examples herein, wherein the linker, when present, can be derivatized with a reactive or other moiety; or a metabolite thereof. In some embodiments, the cytotoxic drug is exatecan, having the following structure:
Figure imgf000113_0001
or a salt thereof. In some aspects, the present disclosure provides a compound of Formula (VII) or (VIII):
Figure imgf000113_0002
or ; WSGR Ref. No: 31362-826.601 wherein: L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety; or a pharmaceutically acceptable salt thereof. In some embodiments, the compound is a compound of Formula (VII):
Figure imgf000114_0001
. In some embodiments, the compound is a compound of Formula (VIII):
Figure imgf000114_0002
. In some embodiments, the reactive moiety W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, - C(O)ORd, -C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein Rb is H or unsubstituted alkyl, Rc is unsubstituted alkyl, and Rd is H, unsubstituted alkyl or a carboxylic acid protecting group. In some embodiments, the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. In some more particular embodiments, the phosphate-based moiety is a pyrophosphate ester. In some embodiments, in addition to the phosphate-based moiety, L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the WSGR Ref. No: 31362-826.601 group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, arylene is phenylene. In some embodiments, each Rw is independently H or methyl. In some further embodiments, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(Rw)-, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, each Rw is independently H or methyl. In some embodiments, reactive moiety W is selected from the group consisting of:
Figure imgf000115_0001
-OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, an activated ester, –O–NH2 and an optionally substituted monocyclic or polycyclic group comprising a cyclooctyne; wherein: Rb is H or unsubstituted C1-C6 alkyl, Rc is unsubstituted C1-C6 alkyl, Rd is H, unsubstituted C1-C6 alkyl or a carboxylic acid protecting group, Rf is H or unsubstituted C1-C6 alkyl, s is 0, 1, 2, 3, 4, 5 or 6, and t is 0, 1, 2, 3, 4, 5 or 6. In some embodiments, the optionally substituted monocyclic or polycyclic group comprising the cyclooctyne is selected from the group consisting of:
Figure imgf000115_0002
, . In some embodiments, W is -ONH2. In some embodiments, the linker L that is joined to W consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and WSGR Ref. No: 31362-826.601 optionally, at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(Rw)- and an amino acid; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl. In some embodiments, the phosphate-based moiety is a pyrophosphate ester. In some embodiments, L is selected from the group consisting of the linkers listed in Table 6. In some embodiments, when the drug-linker is a compound of Formula (VII), then *, when present, denotes the connection to the -N(H) of Formula (VII). In other embodiments, when the drug-linker is a compound of Formula (VIII), then *, when present, denotes the connection to the -O of Formula (VIII). In some embodiments, W is -ONH2. In some further embodiments, L is selected from the group consisting of the linkers listed in Table 7. In some embodiments, when the drug-linker is a compound of Formula (VII), then * denotes the connection to the -N(H) of Formula (VII). In other embodiments, when the drug-linker is a compound of Formula (VIII), then * when denotes the connection to the -O of Formula (VIII). In some embodiments, W is -ONH2. In yet some further embodiments, L is selected from the group consisting of the linkers listed in Table 8. In some embodiments, when the drug-linker is a compound of Formula (VII), then * denotes the connection to the -N(H) of Formula (VII). In other embodiments, when the drug-linker is a compound of Formula (VIII), then * when denotes the connection to the -O of Formula (VIII). In some embodiments, W is -ONH2. In some embodiments, each alkylene of Table 6, Table 7 or Table 8 is independently –(CH2)– , –(CH2)2– or –(CH2)3–;. In some embodiments, each n of Table 6, Table 7 or Table 8 is independently 1, 2 or 3. In some embodiments, L is *–C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)- (CH2CH2)–. In some embodiments, L is *–C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-(O)- (CH2CH2)–. In some embodiments, L has the following structure:
Figure imgf000116_0001
wherein: n is an integer from 1 to 10; q is an integer from 1 to 10; i is 0 or 1; WSGR Ref. No: 31362-826.601 * denotes the connection to drug; and + denotes connection to a reactive moiety. In some embodiments, i is 1. In some embodiments, q is 1. In some embodiments, n is 2. In some other embodiments, L is *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O- alkylene)nn–, wherein each nn is independently an integer from 1 to 100. In some embodiments, L is *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, wherein each nn is independently an integer from 1 to 100. In some embodiments, L has the following structure:
Figure imgf000117_0001
wherein: m is an integer from 1 to 10; n is an integer from 1 to 10; q is an integer from 1 to 10; i is 0 or 1; * denotes the connection to drug; and + denotes connection to a reactive moiety. In some embodiments, i is 1. In some embodiments, n is 2. In some embodiments, m is 1, 2 or 3. In some embodiments, -L-W is selected from the group consisting of:
Figure imgf000117_0002
WSGR Ref. No: 31362-826.601 ;
Figure imgf000118_0001
each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to drug; and each wavy line denotes connection to a reactive moiety. In some further embodiments, each m is independently 1, 2 or 3; each n independently 1, 2 or 3; and each q is independently 1, 2 or 3. In some embodiments, W is -ONH2. In some embodiments, i is 1. In some other embodiments, i is 0. In some embodiments, when * occurs at a carbonyl (-C(O)-) of -L-W, then the compound is a compound of Formula (VII), and the carbonyl of L-W is joined to NH of the compound of Formula (VII). In some embodiments, the compound of Formula (VII) is:
Figure imgf000118_0002
or a pharmaceutically acceptable salt thereof. In some other embodiments, the compound of Formula (VIII) is: WSGR Ref. No: 31362-826.601
Figure imgf000119_0001
or a pharmaceutically acceptable salt thereof. In some other aspects, present disclosure provides a compound of Formula (II):
Figure imgf000119_0002
Drug has the following structure:
Figure imgf000119_0003
n is independently 1 or 2; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2, and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6, and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2; wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene or C1-C6 alkylene WSGR Ref. No: 31362-826.601 substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6, and each j is independently 0, 1, 2, 3, 4, 5 or 6; L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, q is 1, 2, 3, 4, 5 or 6, and r is 1, 2, 3, 4, 5 or 6; or L2b is selected from the group consisting of:
Figure imgf000120_0001
, wherein [*] denotes connection to L3, and each Z1 is independently C(H) or N;
Figure imgf000120_0002
alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof. In some embodiments, Drug is: WSGR Ref. No: 31362-826.601
Figure imgf000121_0001
. In other embodiments, Drug is:
Figure imgf000121_0002
. In some embodiments, there is provided a compound of Formula (II) wherein n is 1. In some embodiments, X and Y are O. In some embodiments, L1 and L2 are absent. In some embodiments, L3 is H2N-O-(CH2)s , wherein s is 1, 2, 3, 4, 5 or 6. In some embodiments, s is 1, 2 or 3. In some embodiments, s is 2. In some embodiments, Linker is O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**] or O-CH2-O-C(O) [**], wherein v is 2, 3, 4, 5 or 6. In some embodiments, Linker is O-CH2 [**] or O-CH2-O-C(O) [**]. In some embodiments, Drug is:
Figure imgf000121_0003
Linker is O-(CH2)v-O-C(O) [**], wherein v is 1, 2, 3, 4, 5 or 6. In some embodiments, v is 1. In some other embodiments, Drug is: WSGR Ref. No: 31362-826.601
Figure imgf000122_0001
Linker is O-(CH2)v [**], wherein v is 1, 2, 3, 4, 5 or 6. In some embodiments, v is 1. In some embodiments, the compound of Formula (II) is:
Figure imgf000122_0002
In some other embodiments, there is provided a compound of Formula (II) wherein n is 2. In some embodiments, X and Y are O. In some embodiments, there is provided a compound of Formula (IIa):
WSGR Ref. No: 31362-826.601
Figure imgf000123_0001
Y is O; each L1 is * (OCH2CH2)m , wherein each m is independently 1, 2, 3, 4, 5 or 6, and * denotes connection to L2b; L2b is:
Figure imgf000123_0002
, wherein [*] denotes connection to L3 and each Z1 is independently C(H) or N; L3 is H2N-O-(CH2)s-C(O)-NH , H2N-O-(CH2)s-C(O) , H2N-O-(CH2)s , H2N-O-(CH2)s-O or H2N-O-(CH2CH2O)s-CH2CH2C(O) ; and each Linker is O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**] or O-CH2-O- C(O) [**], wherein each v is 2, 3, 4, 5 or 6. In some embodiments,
Figure imgf000123_0003
In some other embodiments,
Figure imgf000123_0004
In some embodiments, the compound of Formula (IIa) is: WSGR Ref. No: 31362-826.601
Figure imgf000124_0001
or a pharmaceutically acceptable salt thereof. In some other embodiments, the compound of Formula (IIa) is:
Figure imgf000124_0002
or a pharmaceutically acceptable salt thereof. In some other aspects, the present disclosure provides a compound of Formula (III):
Figure imgf000124_0003
wherein: Drug has the following structure:
Figure imgf000124_0004
WSGR Ref. No: 31362-826.601 n is independently 1 or 2; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6, and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, , wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6, and each j is independently 0, 1, 2, 3, 4, 5 or 6; and L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, q is 1, 2, 3, 4, 5 or 6, and r is 1, 2, 3, 4, 5 or 6; and L3 is H2N-O-(CH2)s-C(O) , H2N-O-(CH2)s , H2N-O-(CH2CH2O)s-CH2CH2C(O) , maleimidyl-(CH2)s-C(O) , maleimidyl-(CH2)s , maleimidyl-(CH2CH2O)sCH2CH2C(O) , Br-CH2- (CO) , Y1-C(O)-(CH2)sC(O) , or Y1-C(O)-(CH2CH2O)s-CH2CH2C(O) , wherein s is 1, 2, 3, 4, 5, or 6 and Y1 is OH or a leaving group; and each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- CH2 [**], (CH2)v-C(O) [**], O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**], O-CH2- O-C(O) [**], NH-(CH2)v [**], (CH2)v(OCH2CH2)w [**], (OCH2CH2)w-(CH2)v [**], (CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - WSGR Ref. No: 31362-826.601 N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof. In some embodiments, Drug has the following structure:
Figure imgf000126_0001
. In some other embodiments, Drug has the following structure:
Figure imgf000126_0002
. In some other aspects, the present disclosure provides a compound of Formula (IV):
Figure imgf000126_0003
each p is independently 0, 1, 2, 3, 4, 5, 6, 7, 8, 910, or p is an integer greater than 10; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; WSGR Ref. No: 31362-826.601 each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6, and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, or L2 is L2c(L2a )3 when n is 3, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6, and each j is independently 0, 1, 2, 3, 4, 5 or 6; L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, q is 1, 2, 3, 4, 5 or 6, and r is 1, 2, 3, 4, 5 or 6; and is a tetravalent moiety selected from the group consisting of C, Si, P, P(=O) and N+;
Figure imgf000127_0001
alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - WSGR Ref. No: 31362-826.601 N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof. In some embodiments, Drug has the following structure:
Figure imgf000128_0001
. In some other embodiments, Drug has the following structure:
Figure imgf000128_0002
. Table 9 provides exemplary drug-linker compounds that can be employed or conjugated with any targeting ligand such as an antibody or antibody fragment, that is selected based in its specificity for an antigen expressed on a target cell or at a target site of interest. The drug-linkers of the invention can be employed with antibody or antibody fragments to a variety of antigens including but not limited to tumor associated antigens, tumor specific antigens, cancer antigens or diseases specific antigens. Non-limiting examples of such antigens include PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD4, CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD37, CD38, CD40L, CD44, CD46, CD47, CD48, CD52, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD80, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD163, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7- H3), CTLA4, integrins, mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, FOLR1, GPC3, PD- 1, PDL-1, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA-125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS- 5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha, and MN/CA IX. In some embodiments, drug-linker compounds disclosed in Table 9 can be employed with anti-HER2 antibody, antibody fragments or antibody drug conjugates of the invention. In some WSGR Ref. No: 31362-826.601 embodiments, drug-linker compounds disclosed in Table 9 can be employed with an anti-HER3 antibody, antibody fragments or antibody drug conjugates of the present disclosure. In some embodiments, drug-linker compounds disclosed in Table 9 can be employed with anti-CD70 antibody, antibody fragments or antibody drug conjugates of the invention. In some embodiments, drug-linker compounds disclosed in Table 9 can be employed with anti-PSMA antibody, antibody fragments or antibody drug conjugates of the invention. In some embodiments, drug-linker compounds disclosed in Table 9 can be employed with an anti-TROP2 antibody, antibody fragments or antibody drug conjugates of the present disclosure. Table 9. Non-limiting Drug-linker Compounds of the Invention
Figure imgf000129_0001
WSGR Ref. No: 31362-826.601
Figure imgf000130_0001
In some embodiments the present invention provides additional drug-linkers prepared using similar procedures as described herein, including the schemes disclosed in the Examples. Additional drug-linker compounds are engineered by linkage of any possible linker group known in the art or elsewhere. The drug-linker compounds are engineered by linkage of one or more phosphate-based linkers via any chemical or functional reactive positions in the drug, for example a nitrogen, halogen, boron, phosphorus, silicon, carbon or oxygen of the cytotoxic agent. Selection of the nitrogen, halogen, boron, phosphorus, silicon, sulfur, carbon or oxygen position in the drug for linkage to a phosphate-based linker is assessed as disclosed elsewhere herein, based on structure of the cytotoxic agent, and using the process known in the art or elsewhere to generate a phosphate-drug linkage. In some embodiments, drug-linkers of the invention include a phosphate-based linker attached or linked at a hydroxyl group of the cytotoxic agent or analogue thereof, such as a topoisomerase inhibitor. In other embodiments, drug-linkers of the invention include a phosphate-based linker attached or linked at a methyl or methylene group of the cytotoxic agent or analogue thereof. In some embodiments, such additional drug-linker compounds can comprise a branched linker, which connects to two identical or different drugs. In some embodiments, drug-linkers of the present invention include drug- linkers generated via linkage of one or more phosphate-based linkers at one or more a nitrogen, halogen, boron, phosphorus, silicon, sulfur, carbon, or oxygen of the cytotoxic agent. In some embodiments, a drug linker compound containing a reactive moiety is conjugated to an antibody or antibody fragment by reacting a drug-linker compound with an antibody, antibody fragment or variant thereof (or simply “antibody”) containing one or more natural or non-natural amino acids. The conjugation reaction provides an ADC, wherein drug-linker is conjugated to a natural or non-natural amino acid of the antibody via a covalent linkage. The covalent linkage can be a product of the reactive moiety of the drug-linker and an additional moiety present in the natural or non-natural amino acid, wherein the additional moiety can react to form the covalent linkage with the reactive moiety. Methods of conjugating drug-linkers to antibodies are known in the art (see, e.g., Johann, K. et al., Polymer Chemistry, 27(11):4396-4407 (2020); Bioconjug Chem., 27(12):2791–2807 (2016); Northrop, B. H. et al., Polymer Chemistry, 18(6):3415-3430 (2015); Axup, WSGR Ref. No: 31362-826.601 J.Y. et al., Proc. Natl. Acad. Sci., 109(40):16101-16016 (2012); Hartmuth, C. et al., Angew. Chem. Int. Ed., 40(11):2004–2021 (2001); Sletten, E.M. and Bertozzi, C. R., Angew. Chem. Int. Ed., 48(38):6974-6998 (2009); WO2006/050262A2; and WO2013/185177A1; the contents of each of which are hereby incorporated by reference in their entirety. Non-limiting examples of reactions and linkages formed between drug-linker compounds and natural or non-natural amino acids incorporated into an antibody of the present disclosure include the following. A. (i) Reaction of a drug-linker comprising -N3 with a non-natural amino acid comprising an alkynyl group, thereby providing a linkage comprising a 4,5-dihydro-1,2,3-triazolyl moiety; or (ii) reaction of a drug-linker comprising an alkynyl group with a non-natural amino acid comprising -N3, thereby providing a linkage comprising a 4,5-dihydro-1,2,3-triazolyl moiety. In some embodiments, the alkynyl group is a cyclooctynyl group. In some embodiments, the non-natural amino acid is p-azido-L-phenylalanine. In some embodiments, the linkage comprising the 4,5- dihydro-1,2,3-triazolyl moiety has the following structure:
Figure imgf000131_0001
; wherein: each s is independently 0 or an integer from 1 to 50; optionally, each s is independently 0, 1, 2, 3, 4, 5 or 6; each t is independently 0 or an integer from 1 to 50; optionally, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. WSGR Ref. No: 31362-826.601 B. (i) Reaction of a drug-linker comprising a tetrazinyl group with a non-natural amino acid comprising an (E)-cyclooctenyl group, thereby providing a linkage comprising a 1,4- dihydropyridazinyl moiety; or (ii) reaction of a drug-linker comprising a tetrazinyl group with a non- natural amino acid comprising an (E)-cyclooctenyl, thereby providing a linkage comprising a 1,4- dihydropyridazinyl moiety. In some embodiments, the linkage comprising the 1,4- dihydropyridazinyl moiety has the following structure:
Figure imgf000132_0001
wherein: each Rf is independently H or alkyl, optionally unsubstituted C1-C6 alkyl; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. C. (i) Reaction of a drug-linker comprising an -ONH2 group with a non-natural amino acid comprising a carbonyl or ketone group, thereby providing a linkage comprising an oxime moiety; or (ii) reaction of a drug-linker comprising a carbonyl or ketone group with a non-natural amino acid comprising an -ONH2 group, thereby providing a linkage comprising an oxime moiety. In some embodiments, the carbonyl or ketone group is -C(O)Rc, wherein Rc is unsubstituted C1-C6 alkyl. In some embodiments, Rc is methyl. In some embodiments, the linkage comprising the oxime moiety has the following structure:
Figure imgf000132_0002
wherein: each Rc is independently unsubstituted C1-C6 alkyl; optionally, each Rc is methyl; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. D. (i) Reaction of a drug-linker comprising a maleimide group with a natural or non-natural amino acid comprising a thiol (-SH), thereby providing a linkage comprising a pyrrolidine-2,5-dione comprising a thiol (-SH) group with a non-natural amino acid comprising a maleimide group, thereby sulfaneyl)pyrrolidine-2,5-dione moiety. In some embodiments, the natural amino acid is cysteine. In WSGR Ref. No: 31362-826.601 sulfaneyl)pyrrolidine-2,5-dione moiety, has the following structure:
Figure imgf000133_0001
wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. E. (i) Reaction of a drug-linker comprising a primary or secondary amine with a natural or non-natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising an amide moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a natural or non-natural amino acid comprising a primary or secondary amine group, thereby providing a linkage comprising a amide moiety. In some embodiments, the natural amino acid is aspartic acid or glutamic acid. In some other embodiments, the natural amino acid is lysine. In some embodiments, the reaction is a peptide coupling reaction or other well-known method of forming an amide, each of which can be performed using methods readily understood by a person of ordinary skill in the art. In some embodiments, the linkage comprising the amide moiety has the following structure:
Figure imgf000133_0002
wherein: each Rb is independently H or alkyl; optionally unsubstituted C1-C6 alkyl; each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. F. (i) Reaction of a drug-linker comprising a hydroxyl group (-OH) with a natural or non- natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising an ester moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a natural or non-natural amino acid comprising a hydroxyl group (-OH), thereby providing a linkage comprising an ester moiety. In some embodiments, the natural amino acid is aspartic acid or glutamic acid. In some other embodiments, the natural amino acid is serine, threonine or tyrosine. Methods of forming such esters linkages can be performed using methods readily understood by a person of WSGR Ref. No: 31362-826.601 ordinary skill in the art. In some embodiments, the linkage comprising the ester moiety has the following structure:
Figure imgf000134_0001
wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. G. (i) Reaction of a drug-linker comprising a thiol group (-SH) with a natural or non-natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising a thioester moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a natural or non-natural amino acid comprising a thiol group (-SH), thereby providing a linkage comprising a thioester moiety. In some embodiments, the natural amino acid is aspartic acid or glutamic acid. In some other embodiments, the natural amino acid is cysteine. Methods of forming such thioesters linkages can be performed using methods readily understood by a person of ordinary skill in the art. In some embodiments, the linkage comprising the ester moiety has the following structure:
Figure imgf000134_0002
wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. H. Reaction of a drug-linker comprising a -C(O)CH2NH2 group with a natural or non- natural amino acid comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group, thereby providing a linkage comprising a -C(O)CH2NHC(O)- moiety; or (ii) reaction of a drug-linker comprising a carboxylic acid group, a protected carboxylic acid, or an activated ester group with a non-natural amino acid comprising a -C(O)CH2NH2 group, thereby providing a linkage comprising a -C(O)CH2NHC(O)- moiety. In some embodiments, the natural amino acid is aspartic acid or glutamic acid. Methods of forming such linkages can be performed using methods readily understood by a person of ordinary skill in the art. In some embodiments, the linkage has the following structure:
Figure imgf000134_0003
WSGR Ref. No: 31362-826.601 wherein: each + denotes connection to a linker of the drug-linker; and each wavy line denotes connection to the antibody. I. Reaction of a drug-linker comprising a thiol group (-SH) with a natural or non-natural amino acid comprising a thiol group, thereby providing a linkage comprising a disulfide. In some embodiments, the natural amino acid is cysteine. Methods of forming disulfide linkages can be performed using methods readily understood by a person of ordinary skill in the art. The present disclosure provides drug moieties with linkers that reduce the toxicity of the moiety in vivo while retaining pharmacological activity. In some embodiments, the toxicity of the linked drug, when administered to an animal or human, is reduced or eliminated compared to the free toxic group or toxic group derivatives comprising labile linkages, while retaining pharmacological activity. In some embodiments, increased doses of the linked toxic group may be administered to animals or humans with greater safety. In certain embodiments, the non-natural amino acid polypeptides linked to a drug moiety (e.g., exatecan or an exatecan derivative or analog) provides in vitro and in vivo stability. In some embodiments, the non-natural amino acid polypeptides linked to a drug moiety are efficacious and less toxic compared to the free drug moiety. In some embodiments, at least one post-translational modification at some position on the polypeptide may occur. In some embodiments the co-translational or post-translational modification occurs via the cellular machinery (e.g., glycosylation, acetylation, acylation, lipid-modification, palmitoylation, palmitate addition, phosphorylation, glycolipid-linkage modification, and the like), in many instances, such cellular-machinery-based co-translational or post-translational modifications occur at the naturally occurring amino acid sites on the polypeptide, however, in certain embodiments, the cellular-machinery-based co-translational or post-translational modifications occur on the non- natural amino acid site(s) on the polypeptide. In other embodiments, the post-translational modification does not utilize the cellular machinery, but the functionality is instead provided by attachment of a molecule (a polymer; a water- soluble polymer; a derivative of polyethylene glycol; a second protein or polypeptide or polypeptide analog; an antibody or antibody fragment; and any combination thereof) comprising a second reactive group to the at least one non-natural amino acid comprising a first reactive group (including but not limited to, non-natural amino acid containing a ketone, aldehyde, acetal, hemiacetal, alkyne, cycloalkyne, azide, oxime, or hydroxylamine functional group) utilizing chemistry methodology described herein, or others suitable for the particular reactive groups. In certain embodiments, the co- translational or post-translational modification is made in vivo in a eukaryotic cell or in a non- eukaryotic cell. In certain embodiments, the post-translational modification is made in vitro not WSGR Ref. No: 31362-826.601 utilizing the cellular machinery. Also included with this aspect are methods for producing, purifying, characterizing and using such a drug-linker containing at least one such co-translationally or post- translationally modified non-natural amino acids. Also included within the scope of the methods, compositions, strategies and techniques described herein are reagents capable of reacting with a drug-linker (containing a carbonyl or dicarbonyl group, alkyne, cycloalkyne, azide, hydroxylamine group, or masked or protected forms thereof) that is part of a polypeptide so as to produce any of the aforementioned post-translational modifications. In certain embodiments, the resulting post-translationally modified drug-linker will contain at least one oxime group; the resulting modified oxime-containing drug-linker may undergo subsequent modification reactions. Also included with this aspect are methods for producing, purifying, characterizing and using such reagents that are capable of any such post-translational modifications of such drug-linkers. In certain embodiments, the polypeptide or non-natural amino acid linked composition includes at least one co-translational or post-translational modification that is made in vivo by one host cell, where the post-translational modification is not normally made by another host cell type. In certain embodiments, the polypeptide includes at least one co-translational or post-translational modification that is made in vivo by a eukaryotic cell, where the co-translational or post-translational modification is not normally made by a non-eukaryotic cell. Examples of such co-translational or post-translational modifications include, but are not limited to, glycosylation, acetylation, acylation, lipid-modification, palmitoylation, palmitate addition, phosphorylation, glycolipid-linkage modification, and the like. In one embodiment, the co-translational or post-translational modification comprises attachment of an oligosaccharide to an asparagine by a GlcNAc-asparagine linkage (including but not limited to, where the oligosaccharide comprises (GlcNAc-Man)2-Man-GlcNAc- GlcNAc, and the like). In another embodiment, the co-translational or post-translational modification comprises attachment of an oligosaccharide (including but not limited to, Gal-GalNAc, Gal-GlcNAc, etc.) to a serine or threonine by a GalNAc-serine, a GalNAc-threonine, a GlcNAc-serine, or a GlcNAc-threonine linkage. In certain embodiments, a protein or polypeptide can comprise a secretion or localization sequence, an epitope tag, a FLAG tag, a polyhistidine tag, a GST fusion, and/or the like. Also included with this aspect are methods for producing, purifying, characterizing and using such polypeptides containing at least one such co-translational or post-translational modification. In other embodiments, the glycosylated non-natural amino acid polypeptide is produced in a non-glycosylated form. Such a non-glycosylated form of a glycosylated non-natural amino acid may be produced by methods that include chemical or enzymatic removal of oligosaccharide groups from an isolated or substantially purified or unpurified glycosylated non- WSGR Ref. No: 31362-826.601 natural amino acid polypeptide; production of the non-natural amino acid in a host that does not glycosylate such a non-natural amino acid polypeptide (such a host including, prokaryotes or eukaryotes engineered or mutated to not glycosylate such a polypeptide), the introduction of a glycosylation inhibitor into the cell culture medium in which such a non-natural amino acid polypeptide is being produced by a eukaryote that normally would glycosylate such a polypeptide, or a combination of any such methods. Also described herein are such non-glycosylated forms of normally-glycosylated non-natural amino acid polypeptides (by normally-glycosylated is meant a polypeptide that would be glycosylated when produced under conditions in which naturally- occurring polypeptides are glycosylated). Of course, such non-glycosylated forms of normally- glycosylated non-natural amino acid polypeptides (or indeed any polypeptide described herein) may be in an unpurified form, a substantially purified form, or in an isolated form. In some instances, incorporation of a non-natural amino acid into the antibody or antibody fragment will be combined with other additions, substitutions, or deletions within the polypeptide to affect other chemical, physical, pharmacologic and/or biological traits. In some cases, the other additions, substitutions or deletions may increase the stability (including but not limited to, resistance to proteolytic degradation) of the polypeptide or increase affinity of the polypeptide for its appropriate receptor, ligand and/or binding proteins. In some cases, the other additions, substitutions or deletions may increase the solubility (including but not limited to, when expressed in E. coli or other host cells) of the polypeptide. In some embodiments, sites are selected for substitution with a naturally encoded or non-natural amino acid in addition to another site for incorporation of a non- natural amino acid for the purpose of increasing the polypeptide solubility following expression in E. coli, or other recombinant host cells. In some embodiments, the polypeptides comprise another addition, substitution, or deletion that modulates affinity for the associated ligand, binding proteins, and/or receptor, modulates (including but not limited to, increases or decreases) receptor dimerization, stabilizes receptor dimers, modulates circulating half-life, modulates release or bio-availability, facilitates purification, or improves or alters a particular route of administration. Similarly, the non- natural amino acid polypeptide can comprise chemical or enzyme cleavage sequences, protease cleavage sequences, reactive groups, antibody-binding domains (including but not limited to, FLAG or poly-His) or other affinity based sequences (including but not limited to, FLAG, poly-His, GST, etc.) or linked molecules (including but not limited to, biotin) that improve detection (including but not limited to, GFP), purification, transport thru tissues or cell membranes, prodrug release or activation, size reduction, or other traits of the polypeptide. Antibody Drug Conjugates (ADCs) WSGR Ref. No: 31362-826.601 Antibody drug conjugates (ADCs) of the present disclosure provide novel therapeutics or anti-cancer drugs by combining the selectivity of antibodies comprising one or more non-natural amino acids and a cytotoxic agent. Targeted cytotoxic drug delivery into tumor tissue increases the therapeutic window of these agents considerably. ADCs of the present disclosure comprise of an antibody bound to a cytotoxic drug via a linker. Stability of the linker between the antibody and the cytotoxic drug is essential for the ADC integrity in circulation. The successful ADC development for a given target antigen depends on optimization of antibody selection, linker design and stability, drug potency and mode of drug and linker conjugation to the antibody. Linker properties of pH and redox sensitivities and protease susceptibility influence circulatory stability and release of the drug moiety. In some embodiments of the disclosure, the antibody of the ADC comprises a full length antibody or fragment thereof that binds to an antigen, and is conjugated to a cytotoxic agent or an immunosuppressive agent, wherein the antibody-drug conjugate exerts: (a) a cytotoxic or cytostatic effect on the antigen-expressing or antigen targeting cell line, or (b) a cytotoxic, cytostatic, or immunosuppressive/immune activating effect on an antigen-expressing immune cell, wherein the conjugation occurs at a non-natural amino acid in the antibody. In some embodiments, the antigen, antigen-expressing cell, or antigen-targeting cell, or antigen-expressing immune cell is PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, C-D123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA-125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha, or MN/CA IX, but is not limited to such. In some embodiments, the antigen, antigen-expressing cell, or antigen-targeting cell, or antigen-expressing immune cell is a TROP2, or HER2 or CD70 antigen, or antigen-targeting cell, or antigen-expressing cell or antigen-expressing immune cell. In some embodiments of the disclosure, the antibody of the ADC comprises a full length antibody or fragment thereof that: binds to TROP2 and is conjugated to a cytotoxic agent or an immunosuppressive agent, wherein the antibody-drug conjugate exerts: (a) a cytotoxic or cytostatic effect on a TROP2-expressing cancer cell line, or (b) a cytotoxic, cytostatic, or immunosuppressive/immune activating effect on a TROP2-expressing immune cell, wherein the conjugation occurs at a non-natural amino acid in the antibody. WSGR Ref. No: 31362-826.601 In some embodiments, the antibody, variant, or composition of the present disclosure may be an antibody, variant, or composition that binds to an antigen receptor. In other embodiments the antibody, variant, or composition may be an antibody, variant, or composition that binds to extracellular surface of an antigen receptor. In some embodiments the antibody, variant, or composition of the present disclosure may be an antibody, variant, or composition that has CDRs grafted onto the framework region of the variable region. In other embodiments the antibody, variant, or composition of the present disclosure may be an antibody, variant, or composition that has a non- natural amino acid. In some embodiments the antibody, variant, or composition may be an antibody, variant, or composition that is described by more than one of the embodiments elsewhere herein the present disclosure. In some embodiments the antibody, antibody variant or antibody composition(s) disclosed herein may be fully humanized. In other embodiments the antibody, antibody variant or antibody composition(s) disclosed herein may be chimeric. In some embodiments the antibody may be an antibody that is full length antibody (Variable + Fc regions), Fab, bispecific, Fab-dimers, Fab- bispecific, Fab-trispecific, bispecific T-cell engagers, dual-affinity re-targeting antibody, IgG1/IgG3 bispecific antibody, diabody, bispecific diabody, scFv-Fc, minibody. In some embodiments, the ADC comprises an antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the antibody. The antibody comprises at least one non-natural amino acid; non-limiting examples of non-natural amino acids are disclosed herein. In some embodiment, the ADC comprises an antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the heavy chain of the antibody. In some embodiments, the ADC comprises an antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the light chain of the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein the conjugation occurs via a non- natural amino acid in the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the heavy chain of the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein the conjugation occurs via a non-natural amino acid in the light chain of the antibody. In some embodiments, the ADC comprises a full-length antibody conjugated to a drug wherein a first conjugation occurs via a non-natural amino acid in the heavy chain of the antibody, and a second conjugation occurs via a non-natural amino acid in the light chain of the antibody. In some embodiments, the full-length antibody comprises two full-length heavy chains and two full-length light chains, wherein a first pair of conjugations occur via a non-natural amino acid in each heavy chain of the antibody, and a second pair of conjugations occur via a non-natural amino acid in each light chain of the antibody. WSGR Ref. No: 31362-826.601 In some embodiments, the drug of the ADC is a cytotoxic drug or agent. In some aspects of the invention, the cytotoxic drug is exatecan, an exatecan derivative or exatecan analog. In some embodiments the drug is a drug generated as described in the Examples herein. In some embodiments, the ADC comprises an antibody, antibody fragment or variant thereof engineered to have one or more non-natural amino acids site specifically incorporated in the heavy and/or light chain amino acid sequence conjugated to drug via a phosphate-based linker. In some other aspects, an ADC of the present disclosure an ADC of Formula (V) or (VI):
Figure imgf000140_0001
wherein: Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids; L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof. In some embodiments, the ADC is an ADC of Formula (V):
Figure imgf000140_0002
. WSGR Ref. No: 31362-826.601 In some embodiments, the ADC is an ADC of Formula (VI):
Figure imgf000141_0001
. In some embodiments, the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. In some embodiments, the phosphate-based moiety is a pyrophosphate ester. In some other embodiments, the phosphate-based moiety is a diphosphonate. In some embodiments, L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)- , -S(O)0-2- and an amino acid, , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each arylene is phenylene. In some embodiments, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(Rw)-, , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. In some embodiments, each Rw is independently H or methyl. In some embodiments, E comprises an amide, an ester, a thioester, a pyrrolidine-2,5-dione, an oxime, a 4,5-dihydro-1,2,3-triazole or a 1,4-dihydropyridazine, wherein the 4,5-dihydro-1,2,3- triazole and the 1,4-dihydropyridazine are each optionally fused to an 8-membered ring. In some embodiments, E is selected from the group consisting of:
Figure imgf000141_0002
WSGR Ref. No: 31362-826.601
Figure imgf000142_0001
wherein: each Rb is independently H or unsubstituted alkyl; each Rc is unsubstituted alkyl; each Rf is independently H or unsubstituted alkyl, each s is independently 0, 1, 2, 3, 4, 5 or 6, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to L; and each wavy line denotes connection to Ab. In some embodiments, each Rb is independently H or unsubstituted C1-C6 alkyl, each Rc is unsubstituted C1-C6 alkyl, and each Rf is independently H or unsubstituted C1-C6 alkyl. In some embodiments, E is:
Figure imgf000142_0002
wherein + denotes connection to L; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl. In some embodiments, Rc is methyl. In some embodiments, L consists of: WSGR Ref. No: 31362-826.601 a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid; , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl. In some embodiments, L is a linker selected from the group of linkers listed in Table 6. In some embodiments, each U, in the linkers listed in Table 6, is independently:
Figure imgf000143_0001
. In some embodiments, wherein L is selected from the group of linkers listed in Table 6, each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–. In some embodiments, each n is independently 1, 2 or 3. In some embodiments, i is 1. In other embodiments, i is 0. In some embodiments, L is a linker selected from the group of linkers listed in Table 7. In some embodiments, wherein L is selected from the group of linkers listed in Table 7, each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–. In some embodiments, each n is independently 1, 2 or 3. In some embodiments, i is 1. In other embodiments, i is 0. In some embodiments, L is a linker selected from the group of linkers listed in Table 8. In some embodiments, wherein L is selected from the group of linkers listed in Table 8, each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–. In some embodiments, each n is independently 1, 2 or 3. In some embodiments, i is 1. In other embodiments, i is 0. In some embodiments, L is selected from the group consisting of: WSGR Ref. No: 31362-826.601
Figure imgf000144_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O of Formula (VI); and each + denotes connection to E. In some embodiments, each m, when present, is independently 1, 2 or 3. In some embodiments, each n is independently 1, 2 or 3. In some embodiments, each q, when present, is independently 1, 2 or 3. In some embodiments, each i is 1. In some embodiments, d is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, d is 1, 2, 3 or 4. In some embodiments, d is 2. In some embodiments, d is 3. In some embodiments, d is 4. In some embodiments, L is: WSGR Ref. No: 31362-826.601
Figure imgf000145_0001
wherein i is 1, n is an integer from 1 to 10, and q is 1. In some further embodiments, n is 1, 2 or 3. Thus, in some embodiments, the ADC of Formula (V) is an ADC of Formula (Va):
Figure imgf000145_0002
; wherein n is an integer from 1 to 10, and d is an integer from 1 to 10. In some embodiments, d is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, d is 1, 2, 3 or 4. In some embodiments, d is 2. In some embodiments, d is 3. In some embodiments, d is 4. In some embodiments, n is 1, 2 or 3. In some further embodiments, n is 2. In yet some further embodiments, E is:
Figure imgf000145_0003
; wherein + denotes connection to (CH2)n; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl. In some embodiments, Rc is methyl. In some other embodiments, L is:
Figure imgf000145_0004
; wherein i is 1, m is an integer from 1 to 10, n is an integer from 1 to 10, and q is 1. In some further embodiments, m is 1, 2 or 3 and n is 1, 2 or 3. Thus, in some embodiments, the ADC of Formula (V) is an ADC of Formula (Vb): WSGR Ref. No: 31362-826.601
Figure imgf000146_0001
; wherein m is an integer from 1 to 10, n is an integer from 1 to 10, and d is an integer from 1 to 10. In some embodiments, d is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, d is 1, 2, 3 or 4. In some embodiments, d is 2. In some embodiments, d is 3. In some embodiments, d is 4. In some embodiments, m is 1, 2 or 3, and n is 1, 2 or 3. In some further embodiments, E is:
Figure imgf000146_0002
; wherein + denotes connection to (CH2CH2O)m; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl. In some embodiments, Rc is methyl. In some other aspects, an ADC of the present invention is represented by the Formula (I):
Figure imgf000146_0003
wherein: Drug has the following structure:
Figure imgf000146_0004
each n is independently 1 or 2; p is 1, 2, 3, 4, 5, 6, 7 or 8; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; WSGR Ref. No: 31362-826.601 each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , C3-C6 cyclic alkylene, * (OCH2CH2)m, unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1- 3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5 or 6; each L2 is independently absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6, and each j is independently 0, 1, 2, 3, 4, 5 or 6, and each L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, each q is independently 1, 2, 3, 4, 5 or 6, and each r is independently 1, 2, 3, 4, 5 or 6; ; or L2b is selected from the group consisting of:
Figure imgf000147_0001
, wherein [*] denotes connection to L3, and each Z1 is independently C(H) or N; each L3 is independently [**]=N-O-(CH2)s-C(O)-NH , [**]=N-O-(CH2)s-C(O) , [**]=N-O-(CH2)s-, [**]=N-O-(CH2)s-O , [**]=N-O-(CH2CH2O)s- CH2CH2C(O) , [**] S-succinimidyl-(CH2)s-C(O) , [**] S-succinimidyl-(CH2)s , [**] S- succinimidyl-(CH2CH2O)sCH2CH2C(O) , [**] S-CH2-(CO) , [**] NH-C(O)-(CH2)s , [**] NH- C(O)-(CH2)sC(O) , or [**] NH-C(O)-(CH2CH2O)s-CH2CH2C(O) , wherein [**] denotes connection to Ab and each s is 1, 2, 3, 4, 5 or 6; or each L3 independently comprises a MC (6-maleimidocaproyl), a MCC (a maleimidomethyl cyclohexane-1-carboxylate), a MP (maleimidopropanoyl), a PAB (p-aminobenzyloxycarbonyl), a WSGR Ref. No: 31362-826.601 SPP (N-Succinimidyl 4-(2-pyridylthio) pentanoate), a SMCC (N-Succinimidyl 4-(N- maleimidomethyl)cyclohexane-1 carboxylate) or a SIAB (N-Succinimidyl (4-iodo- acetyl)aminobenzoate); each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- CH2 [**], (CH2)v-C(O) [**], O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**], O-CH2- O-C(O) [**], NH-(CH2)v [**], (CH2)v(OCH2CH2)w [**], (OCH2CH2)w-(CH2)v [**], (CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; and Ab is an antibody, antibody fragment or variant thereof. In some embodiments, p is 1, 2, 3, 4, 5, 6, 7 or 8. In some embodiments, p is 1, 2, 3 or 4. In some embodiments, p is 2. In some embodiments, p is 3. In some embodiments, p is 4. In some embodiments, n is 1. In some other embodiments, n is 2. In other embodiments, the antibody comprising, containing or incorporating one or more non- natural amino acid is conjugated to the terminal of L3 via a covalent bond. In other embodiments, the antibody comprising, containing or incorporating one or more non-natural amino acid is conjugated to the terminal arm of L3 via an oxime bond. In some embodiments, Drug of Formula (I) has the following structure:
Figure imgf000148_0001
. WSGR Ref. No: 31362-826.601 Further non-limiting embodiments of an ADC of the present disclosure, such as an ADC of Formula (I), Formula (V) or Formula (VI), or a subgenus (e.g., Formula (Va) or (Vb)) or species thereof, are provided below. In some embodiments, Ab is configured to bind to an antigen. In some embodiments, Ab is configured to bind to a tumor-associated antigen (TAA) or cancer antigen. In some embodiments, Ab binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7- H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA- 125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha, and MN/CA IX. In some embodiments, Ab binds to an antigen selected from the group consisting of TROP2, CD70, HER2, HER3 and PSMA. In some embodiments, the one or more non-natural amino acids is selected from the group consisting of para-acetyl phenylalanine, 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine asparagine, O-allyl-L-tyrosine, alpha-N-acetylgalactosamine-O-L-serine, alpha-N- acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L- phenylalanine, 4-amino-L-phenylalanine, 2-amino-L-tyrosine, 3-amino-L-tyrosine, 4-azido-L- phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin-5yl)-L-alanine, 3-borono-L- phenylalanine, 4-borono-L-phenylalanine, 4-bromo-L-phenylalanine, p-carboxymethyl-L- phenylalanine, 4-carboxy-L-phenylalanine, p-cyano-L-phenylalanine, 3,4-dihydroxy-L- phenylalanine (L-DOPA), 4-ethynyl-L-phenylalanine, 2-fluoro-L-phenylalanine, 3-fluoro-L- phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl-beta-D-galactosaminyl)-L- serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L-phenylalanine, 4- isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O-mannopyranosyl-L- serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L-phenylalanine, 3- methyl-L-phenylalanine, O-methyl-L-tyrosine, 3-(2-naphthyl)-L-alanine, 5-nitro-L-histidine, 4- WSGR Ref. No: 31362-826.601 nitro-L-histidine, 4-nitro-L-leucine, 2-nitro-L-phenylalanine, 3-nitro-L-phenylalanine, 4-nitro-L- phenylalanine, 4-nitro-L-tryptophan, 5-nitro-L-tryptophan, 6-nitro-L-tryptophan, 7-nitro-L- tryptophan, 2-nitro-L-tyrosine, 3-nitro-L-tyrosine, O-phospho-L-serine, O-phospho-L-tyrosine, 4- propargyloxy-L-phenylalanine, O-2-propyn-1-yl-L-tyrosine, 4-sulfo-L-phenylalanine and O-sulfo- L-tyrosine. In some embodiments, at least one of the one or more non-natural amino acids is para-acetyl phenylalanine. In some more particular embodiments, at least one of the one or more non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)). In some embodiments, each of the one or more non-natural amino acids is the same. In some embodiments, each of the one or more non-natural amino acids is para-acetyl phenylalanine. In some more particular embodiments, each of the one or more non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)). In some embodiments, Ab comprises a heavy chain having a heavy chain amino acid sequence, a light chain having a light chain amino acid sequence, or both. In some embodiments, the heavy chain comprises at least one of the one or more non-natural amino acids. In some embodiments, the light chain comprises at least one of the one or more non- natural amino acids. In some other embodiments, the light chain does not contain a non-natural amino acid. In some embodiments, Ab comprises two heavy chains, wherein each heavy chain comprises at least one of the one or more non-natural amino acids. In some embodiments, Ab comprises two light chains. In some embodiments, each light chain comprises at least one of the one or more non- natural amino acids. In some other embodiments, each light chain does not contain a non-natural amino acid. In some embodiments, Ab comprises two heavy chains and two light chains, wherein each heavy chain comprises one non-natural amino acid. In some embodiments, each light chain comprises one non-natural amino acid. In some other embodiments, the light chain does not contain a non- natural amino acid. In some embodiments, Ab comprises 1, 2, 3 or 4 non-natural amino acids. In some embodiments, Ab is an anti-trophoblast antigen 2 antibody (anti-TROP2 Ab), antibody fragment or variant thereof. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 1 to 17. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain amino acid sequence is selected from the group consisting of SEQ ID NOs: 5 and 6. In some embodiments, the heavy chain has the amino WSGR Ref. No: 31362-826.601 acid sequence of SEQ ID NO: 5, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 11, wherein one non-natural amino acid occupies position 121. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 4. In some embodiments, the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11. In some embodiments, Ab is an anti-TROP2 monoclonal antibody comprising two heavy chains and two light chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5, and each light chain has the amino acid sequence of SEQ ID NO: 11. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va). In other some embodiments, Ab is an anti-CD70 antibody (anti-CD70 Ab), antibody fragment or variant thereof. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 18 to 24. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 20, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 19. In some other embodiments, the light chain has the amino acid sequence of SEQ ID NO: 24, wherein one non- natural amino acid occupies position 121. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 20. In some embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 19. In some other embodiments, the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 24. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and WSGR Ref. No: 31362-826.601 each E comprises an oxime. In some embodiments, the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va). In some other embodiments, Ab is an anti-HER2 antibody (anti-HER2 Ab), antibody fragment or variant thereof. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 25 to 28. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 26, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti- HER2 Ab, antibody fragment or variant thereof comprises a light chain. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 27. In some other embodiments, the light chain has the amino acid sequence of SEQ ID NO: 28, wherein one non-natural amino acid occupies position 121. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 26. In some embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 27. In some other embodiments, the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 28. In some embodiments, each non-natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va). In some other embodiments, Ab is an anti-PSMA antibody (anti-PSMA Ab), antibody fragment or variant thereof. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 29 to 45. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 36, 38, 40, 42 and 44, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 37, 39, 41, 43 and 45. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 36. In some embodiments, the anti-PSMA Ab, antibody fragment or variant thereof, comprises two light chains. In some embodiments, each light chain has the amino acid sequence of SEQ ID NO: 37. In some embodiments, each non-natural amino acid is para-acetyl- WSGR Ref. No: 31362-826.601 L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va). In yet some other embodiments, Ab is an anti-HER3 antibody (anti-HER3 Ab), antibody fragment or variant thereof. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 46 to 58. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 58, wherein one non-natural amino acid occupies Kabat position 114. In some embodiments, the anti- HER3 Ab, antibody fragment or variant thereof, comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 47 to 57. In some embodiments, the light chain has the amino acid sequence of SEQ ID NO: 47. In some other embodiments, the light chain has the amino acid sequence of SEQ ID NO: 51, wherein one non- natural amino acid occupies position 121. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58. In some embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 47. In some other embodiments, the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51. In some embodiments, Ab is an anti-HER3 monoclonal antibody comprising two heavy chains and two light chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58, and each light chain has the amino acid sequence of SEQ ID NO: 51. In some embodiments, each non- natural amino acid is para-acetyl-L-phenylalanine (pAF), and each E comprises an oxime. In some embodiments, the ADC is an ADC of Formula (V). In some more particular embodiments, the ADC is an ADC of Formula (Va). It is understood that an ADC is typically produced as a composition containing a population of ADCs, i.e., a mixture of ADCs that are essentially identical, except for the drug load. As disclosed herein, an ADC composition can be characterized by a drug-to-antibody ratio (DAR), which reports on the average number of drugs conjugated to antibody in the ADC composition. In some embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 1, about 2, about 3 or about 4, about 5, about 6, about 7 or about 8. In some embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 1, about 2, about 3 or about 4. In some embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 1. In some other embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 2. In some other WSGR Ref. No: 31362-826.601 embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 3. In some other embodiments, an ADC of the present disclosure has a drug to antibody ratio of about 4. In some aspects, the present disclosure provides an ADC composition comprising a mixture of ADCs, wherein each ADC in the mixture is identical, except that the number of drugs or drug- linkers that are conjugated to each ADC can vary. In a non-limiting example, an ADC of the present disclosure comprises a first ADC, a second ADC, a third ADC and a fourth ADC, wherein the first ADC, the second ADC, the third ADC and the fourth ADC are identical, except that the first ADC comprises one drug or drug-linker, the second ADC comprises two drugs or drug-linkers, the third ADC comprises three drugs or drug-linkers, and the fourth ADC comprises four drugs or drug-linkers. In some embodiments, there is provided an ADC composition, comprising: (a) an ADC of Formula (I), wherein p is 1; (b) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 2; (c) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 3; (d) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 4; (e) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 5; (f) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 6; (g) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 7; or (h) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 8; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 8. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, or at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. In some further embodiments, there is provided an ADC composition, comprising: (a) an ADC of Formula (I), wherein p is 1; (b) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 2; (c) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 3; (d) an ADC of Formula (I), wherein the ADC is identical to (a), except that p is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 4. In some other embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. WSGR Ref. No: 31362-826.601 In some other embodiments, there is provided an ADC composition, comprising: (a) an ADC of Formula (V), wherein d is 1; (b) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 3; (d) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 4; (e) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 5; (f) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 6; (g) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 7; (h) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 8; (i) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 9; or (j) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 10; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 10. In some embodiments, the ADC composition is characterized as having a DAR of at least about 1 and at most about 8. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, or at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. In some further embodiments, there is provided an ADC composition, comprising: (a) an ADC of Formula (V), wherein d is 1; (b) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 3; or (d) an ADC of Formula (V), wherein the ADC is identical to (a), except that d is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. In some other embodiments, there is provided an ADC composition, comprising: (a) an ADC of Formula (VI), wherein d is 1; (b) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 3; (d) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 4; (e) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 5; WSGR Ref. No: 31362-826.601 (f) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 6; (g) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 7; (h) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 8; (i) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 9; or (j) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 10; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 10. In some embodiments, the ADC composition is characterized as having a DAR of at least about 1 and at most about 8. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, or at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. In some further embodiments, there is provided an ADC composition, comprising: (a) an ADC of Formula (VI), wherein d is 1; (b) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 2; (c) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 3; or (d) an ADC of Formula (VI), wherein the ADC is identical to (a), except that d is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 2 and at most about 4. In some embodiments, the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. In some embodiments, an ADC or composition of the present disclosure excludes a Toll-like receptor (TLR) agonist. In some aspects of the disclosure, an antibody, antibody fragment, variant or drug conjugate with increased serum half-life, water solubility, bioavailability, therapeutic half-life or circulation time, or with modulated immunogenicity, or with modulated biological activity, is desired. One method of achieving such desired features of the compositions disclosed herein, is by covalent attachment of the polymer polyethylene glycol, (PEG). To maximize the desired properties of PEG, the total molecular weight and hydration state of the polymer or polymers attached to the biologically active molecule must be sufficiently high to impart the advantageous characteristics typically associated with such polymer attachment, such as increased water solubility and circulating half-life, while not adversely impacting the bioactivity of the molecule to which the PEG is attached. PEG derivatives are frequently linked to biologically active molecules through reactive chemical WSGR Ref. No: 31362-826.601 functionalities, such as amino acid residues, the N-terminus, and/or carbohydrate moieties. In some aspects of the present invention, PEG derivatives are linked to biologically active molecules through reactive chemical functionalities to improve biophysical properties of the resulting ADC. WO99/67291 discloses a process for conjugating a protein with PEG, wherein at least one amino acid residue on the protein is substituted with a synthetic amino acid and the protein is contacted with PEG under conditions sufficient to achieve conjugation to the protein. In some aspects of the disclosure antibody, antibody fragments, variant or drug conjugate with increase serum half-life, water solubility, bioavailability, therapeutic half-life, or circulation time, or to modulate immunogenicity, or biological activity is desired. One method of achieving such desired features of the composition disclosed herein, is by covalent attachment of the polymer polyethylene glycol, (PEG). To maximize the desired properties of PEG, the total molecular weight and hydration state of the polymer or polymers attached to the biologically active molecule must be sufficiently high to impart the advantageous characteristics typically associated with such polymer attachment, such as increased water solubility and circulating half-life, while not adversely impacting the bioactivity of the molecule to which the PEG is attached. PEG derivatives are frequently linked to biologically active molecules through reactive chemical functionalities, such as amino acid residues, the N-terminus, and/or carbohydrate moieties. In some aspects of the present invention, PEG derivatives are linked to biologically active molecules through reactive chemical functionalities to improve biophysical properties of the resulting ADC. WO99/67291 discloses a process for conjugating a protein with PEG, wherein at least one amino acid residue on the protein is substituted with a synthetic amino acid and the protein is contacted with PEG under conditions sufficient to achieve conjugation to the protein. Proteins and other molecules often have a limited number of reactive sites available for polymer attachment. The sites most suitable for modification via polymer attachment may play a significant role in receptor binding, and such sites may be necessary for retention of the biological activity of the molecule therefore making them inappropriate for polymer attachment. As a result, indiscriminate attachment of polymer chains to such reactive sites on a biologically active molecule often leads to a significant reduction or even total loss of biological activity of the polymer-modified molecule, PEG attachment can be directed to a particular position within a protein such that the PEG moiety does not interfere with the function of that protein. One method of directing PEG attachment is to introduce a synthetic amino acid into the protein sequence. The protein biosynthetic machinery of the prokaryote Escherichia coli (E. coli) can be altered in order to incorporate synthetic amino acids efficiently and with high fidelity into proteins in response to the amber codon, UAG. See, e.g., J. W. Chin et al., J. Amer. Chem. Soc. 124: 9026-9027, 2002; J. W. Chin, & P. G. Schultz, WSGR Ref. No: 31362-826.601 ChemBioChem 3(11): 1135-1137, 2002; J. W. Chin, et al., PNAS USA 99: 11020-11024, 2002; and, L. Wang, & P. G. Schultz, Chem. Comm., 1: 1-11, 2002. A similar method can be accomplished with the eukaryote, Saccharomyces cerevisiae (S. cerevisiae) (e.g., J. Chin et al., Science 301: 964- 7, 2003). Using this method, a non-natural amino acid can be incorporated into an antibody, variant or drug conjugate of the present disclosure, providing an attachment site for PEG. See, for example WO2010/011735 and WO2005/074650. Methodology and Techniques The present disclosure encompasses methodologies and technologies well known in the art. These include conventional methods of mass spectroscopy, NMR, HPLC, protein chemistry, biochemistry, recombinant DNA techniques and pharmacology, within the skill of the art. Compounds of the present disclosure can be synthesized using several processes or schemes employed in the art. See, e.g., Dubowchik et al., Bioconjugate Chem.13: 855-869, 2002; Doronina et al., Nature Biotechnology 21(7):778-784, 2003; WO2012/166560; WO2013/185117, each incorporated herein by reference. Many methodologies and techniques for synthesis of pharmaceutical, diagnostic or therapeutic compounds are well known to one of ordinary skill in the art. The present disclosure, unless otherwise indicated, also encompass conventional techniques of molecular biology (including recombinant techniques), cell biology, biochemistry and immunology, all within the skill of the art. Such techniques are explained fully in the literature, such as, Molecular Cloning: A Laboratory Manual, Third Edition, Cold Spring Harbor Press, Cold Spring Harbor, NY (Sambrook et al. Eds., 2001); Oligonucleotide Synthesis: Methods And Applications (Methods in Molecular Biology), Herdewijn, P., Ed., Humana Press, Totowa, NJ; Oligonucleotide Synthesis (Gait, M. J., Ed., 1984); Methods In Molecular Biology, Humana Press, Totowa, NJ; Cell Biology: A Laboratory Notebook ,Academic Press, New York, NY (Cellis, J. E., Ed., 1998); Animal Cell Culture (Freshney, R. I., Ed., 1987); Introduction To Cell And Tissue Culture Plenum Press, New York, NY, (Mather, J. P. and Roberts, P. E., Eds., 1998); Cell And Tissue Culture: Laboratory Procedures John Wiley and Sons, Hoboken, NJ, (Doyle, A. et al., Eds., 1993-8); Methods In Enzymology (Academic Press, Inc.) New York, NY; Weir's Handbook Of Experimental Immunology Wiley-Blackwell Publishers, New York, NY, (Herzenberg, L. A. et al. Eds., 1997); Gene Transfer Vectors For Mammalian Cells Cold Spring Harbor Press, Cold Spring Harbor, NY, (Miller, J. M. et al. Eds., 1987); Current Protocols In Molecular Biology, Greene Pub. Associates, New York, NY, (Ausubel, F. M. et al., Eds., 1987); PCR: The Polymerase Chain Reaction, Birkhauser, Boston, MA, (Mullis, K. et al., Eds., 1994); Current Protocols In Immunology, John Wiley and Sons, Hoboken, NJ, (Coligan, J. E. et al., eds., 1991); Short Protocols In Molecular WSGR Ref. No: 31362-826.601 Biology, Hoboken, NJ, (John Wiley and Sons, 1999); Immunobiology 7 Garland Science, London, UK, (Janeway, C. A. et al., 2007); Antibodies. Stride Publications, Devoran, UK, (P. Finch, 1997); Antibodies: A Practical Approach Oxford University Press, USA, New York, NY, (D. Catty., ed., 1989); Monoclonal Antibodies: A Practical Approach Oxford University Press, USA, New York NY, (Shepherd, P. et al. Eds., 2000); Using Antibodies: A Laboratory Manual Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, (Harlow, E. et al. Eds., 1998); The Antibodies Harwood Academic Publishers, London, UK, (Zanetti, M. et al. Eds.1995). Therapeutic Uses of ADCs The antibodies or ADCs of the disclosure are useful for treating a wide range of diseases. disorders, conditions, or cancers. Compositions disclosed herein may be used to modulate an immune response. Modulation of an immune response may comprise stimulating, activating, increasing, enhancing, or up-regulating an immune response. Modulation of an immune response may comprise suppressing, inhibiting, preventing, reducing, or downregulating an immune response. In some embodiments, the ADCs of the present invention may be used for reducing or inhibiting tumor growth or progression in an antigen-expressing cancer or cancer cell comprising an effective amount of the ADC. Disclosed herein are methods of treating a subject for a condition with an ADC or pharmaceutical composition of the disclosure. In some cancers, overexpression of specific cell surface receptors can allow selective targeting of cancerous cells with small molecules or drugs, while minimizing effects on healthy cells. The invention provides a method of treating cancer by administering to a patient a therapeutically-effective amount of an ADC of the invention comprising an antibody or antibody fragment conjugated to a drug-linker disclosed herein. The cancer to be treated by an ADC of the present invention may be, a breast cancer including triple negative breast cancer (TNBC), a brain cancer, a pancreatic cancer, a skin cancer, a lung cancer, a liver cancer, a gall bladder cancer, a colon cancer, an ovarian cancer, a prostate cancer, a uterine cancer, a bone cancer, and a blood cancer (leukemic) cancer or a cancer or disease or conditions related to any of these cancers. In some embodiments, the invention provides a method of treating cancer by administering to a patient a therapeutically-effective amount of an ADC of the invention. The cancer may be an antigen expressing cancer. The cancer may be ovarian cancer including, but not limited to, an epithelial, stromal and germ cell tumor. The ovarian cancer may comprise a fallopian tube cancer or primary peritoneal carcinoma. The cancer may be characterized by high expression of an antigen receptor. The cancer may be treated by recruiting cytotoxic T cells to the antigen receptor expressing tumor cells. In some embodiments, the disclosure provides a method of treating any cancer, disease or condition associated with high expression of antigen receptors by administering to a patient a WSGR Ref. No: 31362-826.601 therapeutically-effective amount of an antibody or ADC of the disclosure. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an antibody or ADC of the invention. In some embodiments, the antibody, antibody fragment or variant thereof binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, C-D123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA-125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha, MN/CA IX but not limited to such. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-TROP2 antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-HER2 antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-HER3 antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-PSMA antibody or ADC of the invention. In some embodiments, the invention provides a method of treating a disorder, or condition, or disease, or cancer by administering to a patient a therapeutically-effective amount of an anti-CD70 antibody or ADC of the invention. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high TROP2 receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high HER2 receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high HER3 receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high PSMA receptor number. In some aspects, the disclosure provides ADCs for use in treating a disease or condition in a cell expressing high CD70 receptor number. The antibodies and ADCs of the disclosure are for use in treating cancer including, but not WSGR Ref. No: 31362-826.601 limited to, ovarian cancer ovarian cancer including, but not limited to, an epithelial, stromal and germ cell tumor. The ovarian cancer may comprise a fallopian tube cancer or primary peritoneal carcinoma. The cancer may be characterized by high expression of antigen receptors, such as ovarian cancer, for example. The cancer may be treated by recruiting cytotoxic T cells to high expressing antigen receptor tumor cells. The antibodies of the disclosure are for use in treating inherited diseases, AIDS, or diabetes but is not limited to such. The antibodies, compounds or composition or conjugates of the disclosure can be used in the manufacture of a medicament for treating a disease or condition in a cell expressing high receptor number. The antibodies, compounds or composition or conjugates of the disclosure can be used in the manufacture of a medicament for treating cancer including, but not limited to, breast cancer including triple negative breast cancer, ovarian cancer including, but not limited to, an epithelial, stromal and germ cell tumor. The antibodies of the invention can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with expression of an antigen receptor such as TROP2, or HER2, or HER3, or PSMA, or CD70, antigen receptor for example. The anti-TROP2 antibodies of the invention can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with high TROP2 receptor numbers. In other embodiments, the anti-HER2 antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with HER2 expression. In other embodiments, the anti-HER3 antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with HER3 expression. In other embodiments, the anti-PSMA antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with PSMA expression. In other embodiments, the anti-CD70 antibodies of the disclosure can be used in the manufacture of a medicament for treating diseases, conditions or cancers related to or associated with CD70 expression. In some embodiments the condition to be treated is a cancer. The cancer may be, but is non- limited to, a breast cancer including triple negative breast cancer (TNBC), a brain cancer, a pancreatic cancer, a skin cancer, a lung cancer, a liver cancer, a gall bladder cancer, a colon cancer, an ovarian cancer, a prostate cancer, a uterine cancer, a bone cancer, and a blood cancer (leukemic) cancer or a cancer or disease or conditions related to any of these cancers. Carcinomas are cancers that begin in the epithelial cells, which are cells that cover the surface of the body, produce hormones, and make up glands. By way of non-limiting example, carcinomas include breast cancer, pancreatic cancer, lung cancer, colon cancer, colorectal cancer, rectal cancer, kidney cancer, bladder cancer, stomach cancer, prostate cancer, liver cancer, ovarian cancer, brain cancer, vaginal cancer, vulvar cancer, uterine cancer, oral cancer, penile cancer, testicular cancer, esophageal cancer, skin cancer, cancer WSGR Ref. No: 31362-826.601 of the fallopian tubes, head and neck cancer, gastrointestinal stromal cancer, adenocarcinoma, cutaneous or intraocular melanoma, cancer of the anal region, cancer of the small intestine, cancer of the endocrine system, cancer of the thyroid gland, cancer of the parathyroid gland, cancer of the adrenal gland, cancer of the urethra, cancer of the renal pelvis, cancer of the ureter, cancer of the endometrium, cancer of the cervix, cancer of the pituitary gland, neoplasms of the central nervous system (CNS), primary CNS lymphoma, brain stem glioma, and spinal axis tumors. In some instances, the cancer is a skin cancer, such as a basal cell carcinoma, squamous, melanoma, nonmelanoma, or actinic (solar) keratosis. In some embodiments the cancer is any cancer with highly expressed antigen receptor numbers such as, for example, TROP2 antigen receptor numbers, HER2 antigen receptor numbers, HER3 antigen receptor numbers, PSMA antigen receptor numbers or CD70 antigen receptor numbers. In some embodiments the condition to be treated is a disease or condition associated with or having a high antigen receptor number such as, for example, TROP2 antigen receptor number, HER2 antigen receptor number, HER3 antigen receptor number, PSMA antigen receptor numbers or CD70 antigen receptor number. The disease or condition may be a pathogenic infection. The pathogenic infection may be a bacterial infection. The pathogenic infection may be a viral infection. The disease or condition may be an inflammatory disease. The disease or condition may be an autoimmune disease. The autoimmune disease may be diabetes. The disease or condition may be a cancer. In some embodiments the disease or condition is any disease or condition with highly expressed antigen receptor numbers such as, for example, TROP2 antigen receptor numbers. The disease or condition may be a pathogenic infection. The biologically active molecule may interact with a cell surface molecule on an infected cell. The biologically active molecule may interact with a molecule on a bacterium, a virus, or a parasite. Pathogenic infections may be caused by one or more pathogens. In some instances, the pathogen is a bacterium, fungi, virus, or protozoan. Exemplary pathogens include but are not limited to: Bordetella, Borrelia, Brucella, Campylobacter, Chlamydia, Chlamydophila, Clostridium, Corynebacterium, Enterococcus, Escherichia, Francisella, Haemophilus, Helicobacter, Legionella, Leptospira, Listeria, Mycobacterium, Mycoplasma, Neisseria, Pseudomonas, Rickettsia, Salmonella, Shigella, Staphylococcus, Streptococcus, Treponema, Vibrio, or Yersinia. The pathogen may be a virus. Examples of viruses include, but are not limited to, adenovirus, coxsackievirus, Epstein-Barr virus, Hepatitis virus (e.g., Hepatitis A, B, and C), herpes simplex virus (type 1 and 2), cytomegalovirus, herpes virus, HIV, influenza virus, measles virus, mumps virus, papillomavirus, parainfluenza virus, poliovirus, respiratory syncytial virus, rubella virus, and varicella-zoster virus. Examples of diseases or conditions caused by viruses include, but are not limited to, cold, flu, hepatitis, AIDS, chicken pox, rubella, mumps, measles, warts, and poliomyelitis. The disease or condition may be an autoimmune disease or autoimmune WSGR Ref. No: 31362-826.601 related disease. An autoimmune disorder may be a malfunction of the body's immune system that causes the body to attack its own tissues. Examples of autoimmune diseases and autoimmune related diseases include, but are not limited to, Addison's disease, alopecia areata, ankylosing spondylitis, antiphospholipid syndrome (APS), autoimmune aplastic anemia, autoimmune hemolytic anemia, autoimmune hepatitis, autoimmune myocarditis, Behcet’s disease, celiac sprue, Crohn’s disease, dermatomyositis, eosinophilic fasciitis, erythema nodosum, giant cell arteritis (temporal arteritis), Goodpasture’s syndrome, Graves' disease, Hashimoto’s disease, idiopathic thrombocytopenic purpura (ITP), IgA nephropathy, juvenile arthritis, diabetes, juvenile diabetes, Kawasaki syndrome, Lambert-Eaton syndrome, lupus (SLE), mixed connective tissue disease (MCTD), multiple sclerosis, myasthenia gravis, pemphigus, polyarteritis nodosa, type I, II, & III autoimmune polyglandular syndromes, polymyalgia rheumatica, polymyositis, psoriasis, psoriatic arthritis, Reiter’s syndrome, relapsing polychondritis, rheumatoid arthritis, sarcoidosis, scleroderma, Sjogren's syndrome, sperm & testicular autoimmunity, stiff person syndrome, Takayasu’s arteritis, temporal arteritis/giant cell arteritis, ulcerative colitis, uveitis, vasculitis, vitiligo, and Wegener’s granulomatosis. The disease or condition may be an inflammatory disease. Examples of inflammatory diseases include, but are not limited to, alveolitis, amyloidosis, angiitis, ankylosing spondylitis, avascular necrosis, Basedow's disease, Bell's palsy, bursitis, carpal tunnel syndrome, celiac disease, cholangitis, chondromalacia patella, chronic active hepatitis, chronic fatigue syndrome, Cogan's syndrome, congenital hip dysplasia, costochondritis, Crohn's Disease, cystic fibrosis, De Quervain’s tendinitis, diabetes associated arthritis, diffuse idiopathic skeletal hyperostosis, discoid lupus, Ehlers-Danlos syndrome, familial mediterranean fever, fascitis, fibrositis/fibromyalgia, frozen shoulder, ganglion cysts, giant cell arteritis, gout, Graves' Disease, HIV-associated rheumatic disease syndromes, hyperparathyroid associated arthritis, infectious arthritis, inflammatory bowel syndrome/ irritable bowel syndrome, juvenile rheumatoid arthritis, Lyme disease, Marfan’s Syndrome, Mikulicz's Disease, mixed connective tissue disease, multiple sclerosis, myofascial pain syndrome, osteoarthritis, osteomalacia, osteoporosis and corticosteroid-induced osteoporosis, Paget's Disease, palindromic rheumatism, Parkinson's Disease, Plummer's Disease, polymyalgia rheumatica, polymyositis, pseudogout, psoriatic arthritis, Raynaud's Phenomenon/Syndrome, Reiter's Syndrome, rheumatic fever, rheumatoid arthritis, sarcoidosis, sciatica (lumbar radiculopathy), scleroderma, scurvy, sickle cell arthritis, Sjogren's Syndrome, spinal stenosis, spondyloisthesis, Still's Disease, systemic lupus erythematosis, Takayasu's (Pulseless) Disease, Tendinitis, tennis elbow/golf elbow, thyroid associated arthritis, trigger finger, ulcerative colitis, Wegener's Granulomatosis, and Whipple's Disease. WSGR Ref. No: 31362-826.601 The pharmaceutical compositions containing an antibody or ADC of the invention may be formulated at a strength effective for administration by various means to a human patient experiencing disorders that may be affected by antibody agonists or antagonists, such as but not limited to, anti-proliferatives, anti-inflammatory, or anti-virals are used, either alone or as part of a condition or disease. Average quantities of an antibody or ADC may vary and in particular should be based upon the recommendations and prescription of a qualified physician. The exact amount of an antibody or ADC is a matter of preference subject to such factors as the exact type of condition being treated, the condition of the patient being treated, as well as the other ingredients in the composition. The disclosure also provides for administration of a therapeutically effective amount of another active agent such as an anti-cancer chemotherapeutic agent or immunotherapeutic agent but is not limited to such. The amount to be given may be readily determined by one skilled in the art based upon therapy with the antibody or ADCs of the invention. Pharmaceutical Compositions In other aspects of the present invention the antibody, antibody fragments, variants or ADCs further comprise a pharmaceutical composition or formulation. Such a pharmaceutical composition can employ various pharmaceutically acceptable excipients, stabilizers, buffers, and other components for administration to animals. See, for example, Remington, The Science and Practice of Pharmacy, 19th ed., Gennaro, ed., Mack Publishing Co., Easton, PA, 1995. Identifying suitable composition or formulations for stability, administration to a subject, and activity varies with each compound as a number of components, (for example, purifying, stabilizing components), need to be considered. Suitable salts for inclusion into the composition or formulation can include, but not limited to, sodium chloride, potassium chloride or calcium chloride. Buffering and/or stabilizing agents such as sodium acetate can be used. Suitable buffers can include phosphate-citrate buffer, phosphate buffer, citrate buffer, L-histidine, L-arginine hydrochloride, bicarbonate buffer, succinate buffer, citrate buffer, and TRIS buffer, either alone or in combination. Surfactants can also be employed, including polysorbates (e.g., polysorbate 80), dodecyl sulfate (SDS), lecithin either alone or in combination. In some aspects of the present invention, the pharmaceutical composition or formulation can be an aqueous composition or in the form of a reconstituted liquid composition or as a powder. The composition or formulation can have a pH range from about 4.0 to about 7.0 or from about 4.5 to about 6.5 when the formulation is in a liquid form. However, the pH can be adjusted to provide acceptable stability and administration by the skilled medical practitioner. The composition can be stored in a vial or cartridge, a pen delivery device, a syringe, intravenous administration tubing or an intravenous administration bag but is not limited to such. In WSGR Ref. No: 31362-826.601 other embodiments a pharmaceutical composition of the invention can be administered as a single dose or followed by one or more subsequent dose(s) minutes, days, or weeks after the first dose. Further administrations may be contemplated as needed to treat, reduce or prevent a cancer, condition, disorder or disease. In some instances, the antibodies, antibody fragments, variants, or ADCs of the present invention disclosure may be used in conjunction with an additional therapy or treatment including but not limited to surgery, radiation, cryosurgery, thermotherapy, hormone treatment, chemotherapy, vaccines and other immunotherapies. In some embodiments such additional treatment can include a therapeutic agent such as chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid or combination thereof. In other embodiments the antibodies, antibody fragments, variants, or ADCs of the invention can be administered with one or more immunostimulatory agents to induce or enhance an immune response. Immunostimulatory agents that can stimulate specific arms of the immune system, such as natural killer (NK) cells that mediate antibody-dependent cell cytotoxicity (ADCC). Such immunostimulatory agents include, but are not limited to, IL-2, immunostimulatory oligonucleotides embodiments the ADCs of the invention can be administered with one or more immunomodulators including, but not limited to, cytokines, chemokines (including, but are not limited to, SLC5 ELC, that immunizes a subject against an antigen such as, for example, TROP2, HER2, HER3, PSMA or CD70. Such vaccines, in some embodiments, include antigens, with, optionally, one or more adjuvants to induce or enhance an immune response. Adjuvants of many kinds are well known in the art. The chemotherapeutic agent or any agent involved in treating, reducing or preventing a disease, condition or cancer in a subject in need thereof can also be administered in combination with an ADC of the invention disclosure. Chemotherapeutic agents may include, but are not limited to, erlotinib (TARCEVA®, Genentech/OSI Pharm.), bortezomib (VELCADE®, Millennium Pharm.), fulvestrant (FASLODEX®, AstraZeneca), sutent (SU11248, Pfizer), letrozole (FEMARA®, Novartis), imatinib mesylate (GLEEVEC®, Novartis), PTK787/ZK 222584 (Novartis), oxaliplatin (Eloxatin®, Sanofi), 5-FU (5-fluorouracil), leucovorin, Rapamycin (Sirolimus, RAPAMUNE®, Wyeth), lapatinib (TYKERB®, GSK572016, GlaxoSmithKline), lonafarnib (SCH 66336), sorafenib (BAY43-9006, Bayer Labs.), and gefitinib (IRESSA®, AstraZeneca), AG1478, AG1571 (SU 5271; Sugen), alkylating agents such as thiotepa and CYTOXAN® cyclosphosphamide; alkyl sulfonates such as busulfan, improsulfan and piposulfan; antifolate antineoplastic such as pemetrexed WSGR Ref. No: 31362-826.601 (ALIMTA®, Eli Lilly), aziridines such as benzodopa, carboquone, meturedopa, and uredopa; ethylenimines and methylamelamines including altretamine, triethylenemelamine, triethylenephosphoramide, triethylenethiophosphoramide and trimethylomelamine; acetogenins (especially bullatacin and bullatacinone); a camptothecin (including the synthetic analogue topotecan); bryostatin; callystatin; CC-1065 (including its adozelesin, carzelesin and bizelesin synthetic analogues); cryptophycins (particularly cryptophycin 1 and cryptophycin 8); dolastatin; duocarmycin (including the synthetic analogues, KW-2189 and CB1-TM1); eleutherobin; pancratistatin; a sarcodictyin; spongistatin; nitrogen mustards such as chlorambucil, chlornaphazine, cholophosphamide, estramustine, ifosfamide, mechlorethamine, mechlorethamine oxide hydrochloride, melphalan, novembichin, phenesterine, prednimustine, trofosfamide, uracil mustard; nitrosoureas such as carmustine, chlorozotocin, fotemustine, lomustine, nimustine, and ranimnustine; antibiotics such as the enediyne antibiotics, calicheamicin, calicheamicin gamma and calicheamicin omega; dynemicin, including dynemicin A; bisphosphonates, such as clodronate; an esperamicin; as well as neocarzinostatin chromophore and related chromoprotein enediyne antibiotic chromophores, aclacinomysins, actinomycin, anthramycin, azaserine, bleomycins, cactinomycin, carabicin, caminomycin, carzinophilin, chromomycinis, dactinomycin, daunorubicin, detorubicin, 6-diazo-5- oxo-L-norleucine, ADRIAMYCIN® doxorubicin (including morpholino-doxorubicin, cyanomorpholino-doxorubicin, 2-pyrrolino-doxorubicin and deoxydoxorubicin), epirubicin, esorubicin, idarubicin, marcellomycin, mitomycins such as mitomycin C, mycophenolic acid, nogalamycin, olivomycins, peplomycin, potfiromycin, puromycin, quelamycin, rodorubicin, streptonigrin, streptozocin, tubercidin, ubenimex, zinostatin, zorubicin; anti-metabolites such as methotrexate and 5-fluorouracil (5-FU); folic acid analogues such as denopterin, methotrexate, pteropterin, trimetrexate; purine analogs such as fludarabine, 6-mercaptopurine, thiamiprine, thioguanine; pyrimidine analogs such as ancitabine, azacitidine, 6-azauridine, carmofur, cytarabine, dideoxyuridine, doxifluridine, enocitabine, floxuridine; androgens such as calusterone, dromostanolone propionate, epitiostanol, mepitiostane, testolactone; antiandrogens or androgen deprivation therapy; anti-adrenals such as aminoglutethimide, mitotane, trilostane; folic acid replenisher such as frolinic acid; aceglatone; aldophosphamide glycoside; aminolevulinic acid; eniluracil; amsacrine; bestrabucil; bisantrene; edatraxate; defofamine; demecolcine; diaziquone; elformithine; elliptinium acetate; an epothilone; etoglucid; gallium nitrate; hydroxyurea; lentinan; lonidainine; maytansinoids such as maytansine and ansamitocins; mitoguazone; mitoxantrone; mopidanmol; nitraerine; pentostatin; phenamet; pirarubicin; losoxantrone; podophyllinic acid; 2- ethylhydrazide; procarbazine; PSK® polysaccharide complex (JHS Natural Products, Eugene, OR); razoxane; rhizoxin; sizofuran; spirogermanium; tenuazonic acid; triaziquone; 2,2',2''- WSGR Ref. No: 31362-826.601 trichlorotriethylamine; trichothecenes (especially T-2 toxin, verracurin A, roridin A and anguidine); urethan; vindesine; dacarbazine; mannomustine; mitobronitol; mitolactol; pipobroman; gacytosine; arabinoside ("Ara-C"); cyclophosphamide; thiotepa; taxoids, e.g., paclitaxel (TAXOL®, Bristol- Myers Squibb Oncology, Princeton, N.J.), ABRAXANE Cremophor-free, albumin, nanoparticle formulation of paclitaxel (American Pharmaceutical Partners, Schaumberg, Ill.), and TAXOTERE® doxetaxel (Rhone-Poulenc Rorer, Antony, France); chloranbucil; GEMZAR® gemcitabine; 6- thioguanine; mercaptopurine; methotrexate; platinum analogs such as cisplatin and carboplatin; vinblastine; platinum; etoposide (VP-16); ifosfamide; mitoxantrone; vincristine; NAVELBINE® vinorelbine; novantrone; teniposide; edatrexate; daunomycin; aminopterin; xeloda; ibandronate; CPT-11; topoisomerase inhibitor RFS 2000; difluoromethylornithine (DMFO); retinoids such as retinoic acid; capecitabine; and pharmaceutically acceptable salts, acids or derivatives of any of the above. EXAMPLES It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. Example 1: General Experimental Procedures Chemical reagents and solvents were obtained from the following sources unless expressly indicated otherwise: 1 ClickChemistry Inc. (Kendall Park, NJ), AA Blocks LLC (San Diego, CA), ACES PHARMA (Princeton, NJ), AK Scientific, Inc. (Union City, CA), Ascension Chemical Company (Woodbridge, CT), AURUM Pharmatech LLC (Plano, TX), BOC Sciences (Shirley, NY), BroadPharm (San Diego, CA), Chem-Impex International, Inc. (Wood Dale, Illinois), Combi-Blocks, Inc. (San Diego, CA), Enamine US, Inc. (Cincinnati, OH), eNovation Chemicals LLC (Green Brook, NJ), Fisher Scientific (Waltham, MA), MedChemExpress LLC (Monmouth Junction, NJ), Quanta BioDesign, Ltd. (Plain City, OH), Sigma Aldrich (St. Louis, MO), MilliporeSigma (Burlington, MA), SiliCycle Inc. (Quebec City, Quebec CANADA) and Synthonix, Inc. (Wake Forest, NC). Exatecan mesylate (CAS: 169869-90-3) is available from commercial suppliers including MedChemExpress, located at 1 Deerpark Dr # Q, Monmouth Junction, NJ 08852, as Catalog No.: HY-13631. Chemical names of compounds were derived from chemical structures using ChemDraw version 20.1.1 or 20.2.0 (CambridgeSoft) or Scilligence ELN version 6.8.4. Abbreviations used in the Examples herein: ACN: acetonitrile, CDI: 1,1'- carbonyldiimidazole, DAD: diode array detection/detector, DBU: 1,8-diazabicyclo[5.4.0]undec-7- ene, DCM: dichloromethane, DIEA: N,N-diisopropylethylamine, DIAD: diisopropyl WSGR Ref. No: 31362-826.601 azodicarboxylate, DMF: dimethylformamide, DMTMMT: 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4- methylmorpholinium tetrafluoroborate, EDC: 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide HCl, ELSD: evaporative light scattering detection/detector, EtOAc: ethyl acetate, EtOH: ethanol, HATU: 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate, HPLC: high performance liquid chromatography, HOBt: hydroxybenzotriazole, LC: liquid chromatography, MeOH: methanol, MS: mass spectrometry, NIS: N-iodosuccinimide, TEA: triethylamine, TFA: trifluoroacetic acid, THF: tetrahydrofuran, TLC: thin layer chromatography. Example 2: Synthesis of compound 10 General Procedure for the synthesis of Compound 10 All commercially available anhydrous solvents were used without further purification. DMF was dried over molecular sieve pack 4Å powder (Bide Pharmatech). TLC was performed on Liang Chen Silica gel GF254 plates using UV light for visualization. Chromatographic purification was performed on Flash Column Silica-CS from Agela Technologies using conditions detailed in the experimental procedure. Preparative HPLC was performed on Gilson 281 system using a Waters Xbridge Prep OBD C1810 µm 150 × 40 mm column. NMR spectral data were collected on a 400 deuterium solvent signal. Coupling constants (J) are reported in hertz (Hz). Spin multiplicities are described as: s (singlet), br (broad), d (doublet), dd (doublet of doublets), t (triplet), q (quartet) or m (multiplet). LCMS was performed using an Agilent LCMS-6130 system with Agilent LabSolutions software for data processing, or an Agilent 1200 Infinity Binary LC coupled with 6130 Accurate- Mass MS system for ESI analysis, using analytical methods described below. Analytical Method 1: LCMS was performed using an Agilent Poroshell 2.7 µm SB-C18, 3.0 × 30 mm column. Detection methods were DAD and MS with positive electrospray ionization with a range of 50-2000. Mobile phase A was 0.04% TFA in water, and mobile phase B was 0.02% TFA in HPLC grade ACN. The gradient was 5-95% B over 0.70 min, 95% B (0.70-1.16min), 95-5% B (1.16-1.50min). The flow rate was 1.5 mL/min. Analytical Method 2: LCMS was performed using an Agilent Poroshell 2.7 µm SB-C18, 3.0 × 30 mm column. Detection methods were DAD and and MS positive electrospray ionization with a range of 50-2000. Mobile phase A was 0.04% TFA in water, and mobile phase B was 0.02% TFA in HPLC grade ACN. The gradient was 10-100% B over 0.70 min with a hold at 100% B for 0.40 min. The flow rate was 1.5 mL/min. Analytical Method 3: LC/MS was performed using an Agilent Zorbax 5 µm / XBridge C18, 2.1 × 50 mm column. Detection methods were DAD and MS with negative electrospray ionization WSGR Ref. No: 31362-826.601 with a range of 50-2000. Mobile phase A was 10 mM ammonium bicarbonate in water, and mobile phase B was HPLC grade ACN. The gradient was 5-95% B over 0.70 min, 95% B (0.70-1.16min), 95-5% B (1.16-1.50 min) with a hold at 5% B for 0.34 min. The flow rate was 1.5 mL/min. Analytical Method 4: LC/MS was performed using an Agilent Zorbax 5 µm / XBridge C18, 2.1 × 50 mm column. Detection methods were DAD and MS with negative electrospray ionization with a range of 50-2000. Mobile phase A was 10 mM ammonium bicarbonate in water, and mobile phase B was HPLC grade ACN. The gradient was 5-95% B over 2.50 min with a hold at 95% B for 0.50 min, 95-5% B (3.00-3.01 min) with a hold at 5% B for 0.49 min. The flow rate was 1 mL/min. Analytical Method 5: LC/MS was performed using an Agilent Zorbax 5 µm / XBridge C18, 2.1 × 50 mm column. Detection methods were DAD, ELSD and MS with negative electrospray ionization with a range of 100-1000. Mobile phase A was H2O plus 10 mM NH4HCO3, and mobile phase B was ACN. The gradient was 5% B over 0.40 min and 5-95% B at 0.40-3.40 min, hold at 95% B for 0.45 min, and then 95-5% B in 0.01 min. The flow rate was 0.8 mL/min. Analytical Method 6: HPLC was performed using an Agilent Zorbax 5 µm / XBridge C18, 2.1 × 50 mm column. The detection method was DAD. Mobile phase A was 10 mmol/L NH4HCO3 in water, and mobile phase B was 100% ACN. The gradient was 10-80% B over 4.50 min, with a hold at 80% B for 0.91 min (flow rate was 0.8 mL/min), then 80-10% B in 0.01 min with a hold at 10% for 0.58 min (flow rate 1.2 mL/min). Compound 8 was synthesized according to the following scheme:
Figure imgf000169_0001
. tert-Butyl (2-hydroxyethoxy)carbamate (8-1). To a solution of 2-bromoethanol (11.26 g, 90.13 mmol, 1.2 eq) in ACN (15 mL) was added N-Boc-hydroxylamine (10 g, 75.11 mmol, 1 eq) and DBU (12.58 g, 82.62 mmol, 1.1 eq) at 20 °C. After addition, the mixture was stirred at 40 °C for 24 hrs. TLC showed the starting material was consumed and desired product was detected. The mixture was concentrated under vacuum to give a residue. The residue was purified by column chromatography on silica gel (petroleum ether/ethyl acetate, 50/1 to 30/1) to give compound 8-1 (5 g, 22.57 mmol, 30.06% yield) as colorless oil.
Figure imgf000169_0002
. WSGR Ref. No: 31362-826.601 tert-Butyl (2-((bis(benzyloxy)phosphoryl)oxy)ethoxy)carbamate (8-2). To a solution of compound 8-1 (6 g, 33.86 mmol, 1 eq) in DMA (14 mL) was added 1H-tetrazole (5.93 g, 84.65 mmol, 2.5 eq), N-dibenzyloxyphosphanyl-N-isopropyl-propan-2-amine (14.62 g, 42.33 mmol, 1.25 eq) at 0 °C. Then the mixture was stirred at 20 °C for 12 hrs. The mixture was cooled to 0 °C and H2O2 (9.60 g, 84.65 mmol, 30% purity, 2.5 eq) was added dropwise and stirred for additional 2 hrs. LCMS showed the reaction was completed. Then the mixture was quenched with saturated NaHSO3 solution (20 mL) and extracted with ethyl acetate (3 × 30 mL), and the combined organic phase was washed with saturated NaHCO3 solution (50 mL) and brine (50 mL), dried over anhydrous Na2SO4, filtered, and concentrated under vacuum to give crude product, which was purified by column chromatography on silica gel (petroleum ether/ethyl acetate=100/1 to 30/1) to give compound 8-2 (5.3 g, 10.90 mmol, 32.21% yield) as a light yellow oil.1H NMR: (CD3 1H), 7.31-7.38 (m, 10H), 5.07 (dd, J=8.2, 1.6 Hz, 4H), 4.17-4.26 (m, 2H), 3.98 (dd, J=4.5, 3.5 Hz, 2H), 1.47 (s, 9H).
Figure imgf000170_0001
. tert-Butyl (2-(phosphonooxy)ethoxy)carbamate (8). To a solution of compound 8-2 (4 g, 8.23 mmol, 1 eq) in EtOH (40 mL) was added Pd-C (5 g, 10% purity) and TEA (2.50 g, 24.69 mmol, 3 eq). The mixture was stirred at 20 °C for 3 hrs under H2 (15 Psi, balloon). LCMS showed the reaction was completed. The mixture was filtered, and the filtrate was concentrated under vacuum to give compound 8 (2.9 g, 7.69 mmol, 93.41% yield, TEA) as a white solid.1H NMR: (DMSO-d6, J =7.2 Hz, 6H), 1.40 (s, 9H), 1.15 (br t, J =7.2 Hz, 9H). . Compound 10 was synthesized according to the following scheme: WSGR Ref. No: 31362-826.601
Figure imgf000171_0001
Chloromethyl ((1S,9S)-9-ethyl-5-fluoro-9-hydroxy-4-methyl-10,13-dioxo- 2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1- yl)carbamate (1). To a solution of exatecan mesylate (500 mg, 940.64 µmol, 1 eq) in DCM (40 mL) was added DIEA (364.71 mg, 2.82 mmol, 3 eq) and chloromethyl carbonochloridate (181.93 mg, 1.41 mmol, 1.5 eq) in DCM (10 mL) at -20 °C. The mixture was stirred at -20 °C for 1 hr, and then stirred at 20 °C for 2 hrs. LCMS (Method 1) showed the starting material was consumed. The reaction mixture was quenched with ice water (50 mL), then separated. The aqueous layer was extracted with DCM (2 × 20 mL). The combined organic phase was washed with brine (2 × 10 mL), dried over Na2SO4, filtered, and the filtrate was concentrated under reduced pressure to give WSGR Ref. No: 31362-826.601 compound 1 (500 mg, 473.55 µmol, 50.34% yield, 50% purity) as a yellow solid, which was directly used for the next step [LCMS (Method 2), m/z 528.1 (M+H)+, Rt: 0.663 min].
Figure imgf000172_0001
((Bis(benzyloxy)phosphoryl)oxy)methyl ((1S,9S)-9-ethyl-5-fluoro-9-hydroxy-4-methyl- 10,13-dioxo-2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2- b]quinolin-1-yl)carbamate (2). To a solution of compound 1 (400.00 mg, 378.84 µmol, 1 eq) in toluene (20 mL) was added silver dibenzyl phosphate (175.07 mg, 454.61 µmol, 1.2 eq). The mixture was stirred at 60 °C for 1 hr. LCMS (Method 1) showed the reaction was completed. The mixture was filtered and the filtrate was concentrated under reduced pressure to give a residue. The residue was purified by column chromatography (SiO2, ethyl acetate in petroleum ether = 0-100%) to give compound 2 (200 mg, 259.84 µmol, 27.6% yield for 2-step) as a yellow solid [LCMS (Method 1), m/z 770.3 (M+H)+, Rt: 0.818 min].
Figure imgf000172_0002
. (Phosphonooxy)methyl ((1S,9S)-9-ethyl-5-fluoro-9-hydroxy-4-methyl-10,13-dioxo- 2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1- yl)carbamate (3). To a mixture of Pd/C (100 mg, 10% purity) in EtOH (10 mL) was added a solution of 2 (100 mg, 129.92 µmol) in EtOH (10 mL). The mixture was degassed and purged 3 times with H2, and then the mixture was stirred at 20 °C for 2 hrs under hydrogen balloon. LCMS (Method 3) showed the starting material was consumed and about 66% product with desired m/z was generated. WSGR Ref. No: 31362-826.601 The mixture was filtered, and the filtered cake was washed with EtOH (10 × 20 mL). The combined filtrate was concentrated under reduced pressure to give 3 (50 mg, 84.82 µmol, 65.29% yield) as a yellow solid which was used directly without purification. [LCMS (Method 3) m/z 588.1, (M-H)-, Rt: 0.641 min].
Figure imgf000173_0001
(((((2-(((tert-Butoxycarbonyl)amino)oxy)ethoxy)(hydroxy)phosphoryl)oxy)(hydroxy)- phosphoryl)oxy)methyl ((1S,9S)-9-ethyl-5-fluoro-9-hydroxy-4-methyl-10,13-dioxo- 2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1- yl)carbamate (9). To a solution of compound 3 (30 mg, 50.89 µmol, 1 eq) in DMF (1 mL) was added activated compound 8 (31.27 mg, 101.79 µmol, 2 eq) and ZnCl2 (27.75 mg, 203.58 µmol, 4 eq). The mixture was stirred at 25 °C for 12 hrs. LCMS (Method 4) showed the starting material was consumed. The mixture was concentrated under reduced pressure and co-evaporated with toluene to give compound 9 as crude product for direct use in next step. [LCMS (Method 4), m/z
Figure imgf000173_0002
. (((((2-(Aminooxy)ethoxy)(hydroxy)phosphoryl)oxy)(hydroxy)phosphoryl)oxy)-methyl ((1S,9S)-9-ethyl-5-fluoro-9-hydroxy-4-methyl-10,13-dioxo-2,3,9,10,13,15-hexahydro-1H,12H- benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1-yl)carbamate (10). To a solution of compound 9 (crude from last step) in DCM (1 mL) was added TFA (0.5 mL). The mixture was WSGR Ref. No: 31362-826.601 stirred at 20 °C for 1 hr. LCMS (Method 4) showed the starting material was consumed. The combined reaction mixture was concentrated under reduced pressure and co-evaporated with dichloromethane to give a residue. The procedure starting with the same amount of compound 3 (30 mg, 50.89 µmol) was repeated to obtain an additional batch of compound 9. The residue from the two batches was combined and purified by prep-HPLC (column: C18150 x 30 mm, 5µm; mobile phase: water (NH4HCO3)-ACN; B%: 10%-40%,10 min) and the desired fractions were lyophilized to give target compound 10 as a white solid (4.1 mg, 4.83 µmol, 4.75% 2-step yield from compound 3, bis-ammonium salt). HPLC (Method 6): Rt: 1.448 min. [LCMS (Method 5), m/z 727.1, (M-H)-, Rt: 1.920 min].1 J = 8.1 Hz, 1H), 7.77 (d, J = 11.0 Hz, 1H), 7.40 - 7.08 (m, 6H), 5.52 (br dd, J = 4.8, 12.4 Hz, 1H), 5.42 (s, 1H), 5.37 (br dd, J = 5.1, 10.8 Hz, 1H), 5.28 (br s, 2H), 3.89 - 3.84 (m, 2H), 3.72 - 3.63 (m, 4H), 2.38 (s, 3H), 2.20 (br s, 2H), 1.95 - 1.78 (m, 2H), 0.87 (t, J = 7.3 Hz, 3H).
Figure imgf000174_0001
Example 3: Synthesis of Compound 16 General Procedure for the synthesis of Compound 16 All commercially available anhydrous solvents were used without further purification and were stored under a nitrogen atmosphere. TLC was performed on Merck Silica gel 60 F254 plates using UV light and/or staining with aqueous KMnO4 solution for visualization. Chromatographic purification was performed on Combi Flash Rf from Teledyne ISCO using conditions detailed in the experimental procedure. Preparative HPLC was performed on Shimadzu system using Gemini-NX C185 µm 100 x 30 mm, 150 x 30 mm or 250 x 50 mm column, depending on the scale. MS was performed on a Shimadzu LCMS-2020 system and data were processed using Shimadzu LabSolutions software. Agilent 1260 Infinity Binary LC coupled with 6230 Accurate-Mass TOFMS system was used for HR-ESI-TOF analysis. Analytical HPLC was performed on Shimadzu system using either an Agilent Zorbax 1.8 µm / SR-C182.1 × 50 mm, or a Waters BEH 1.7 pm v2.1 x 50 mm column, using methods described below. WSGR Ref. No: 31362-826.601 Analytical Method 7: Mobile phase A was 0.05% formic acid in water, and mobile phase B was 0.05% formic acid in 90% ACN aqueous solution. The gradient was 5% B for 0.02 min, 5-90% B from 0.02 min to 2.20 min, 90% B from 2.20 min to 4.20 min, and 90-10% B from 4.40 to 5.10 min. The flow rate was 1 mL/min. Analytical Method 8: Mobile phase A was 10 mM ammonium bicarbonate in water, and mobile phase B was 5% of 10 mM ammonium bicarbonate in 95% ACN solution. The gradient was 5% B for 1.02 min, 5-30% B from 1.02 to 4.20 min, 30-90% B from 4.20 to 5.00 min, 90% B from 5.00 min to 5.50 min, and 90-5% B from 5.50 to 6.60 min. The flow rate was 1 mL/min. Compound 16 was synthesized according to the following schemes.
Figure imgf000175_0001
WSGR Ref. No: 31362-826.601
Figure imgf000176_0001
. tert-Butyl ((1S,9S)-9-ethyl-5-fluoro-9-hydroxy-4-methyl-10,13-dioxo-2,3,9,10,13,15- hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1-yl)carbamate (Boc- Exatecan; 11). To a mixture of exatecan mesylate (310 mg, 0.583 mmol) and Boc anhydride (255 mg, 1.17 mmol) in DCM (5 mL) was added diisopropylethylamine amine (0.30 mL, 1.75 mmol), and the mixture was then stirred overnight at room temperature. After 20 h, LCMS (Method 7) showed the reaction completion. The mixture was diluted with ~10 ml of EtOAc, transferred to 125 ml separatory funnel, and then washed with 20 mL of NH4Cl and 20 mL of brine. Combined organic layers were dried over MgSO4, and then filtered. The solvent was removed by rotary evaporator, and the residue was dried on high vacuum pump for 3 hr. Pure product (compound 11) was obtained as white-beige solid (287 mg, 92% yield). LCMS (Method 7) Calculated for C29H31FN3O6 (M+H)+ = 536.2; observed 536.0.
Figure imgf000176_0002
. tert-Butyl ((1S,9S)-9-ethyl-5-fluoro-4-methyl-9-((methylthio)methoxy)-10,13-dioxo- 2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1- yl)carbamate (Boc-exatecan thioether; 12). To a mixture of compound 11 (225 mg, 0.42 mmol) in WSGR Ref. No: 31362-826.601 DMSO (7.36 mL, 0.057 M), was added acetic anhydride (3.68 mL, 0.114 M) and acetic acid (0.99 mL, 0.408 M) at room temperature. The mixture was stirred at room temperature overnight. Both TLC and LCMS (Method 7) showed the formation of the desired product. The mixture was quenched by addition of 10 mL of water. Then, the mixture was diluted with 10 mL of brine and extracted with DCM (3 x 15 mL). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated using rotary evaporator. The crude was product was purified via flash column chromatography, in which pure product was eluted at 5% MeOH/DCM to give (146 mg, 58% yield) of pure product (compound 12) as light green solid. LCMS (Method 7) Calculated for C31H35FN3O6S (M+H)+ = 596.2; observed 596.0.
Figure imgf000177_0001
. tert-Butyl ((1S,9S)-9-(((bis(benzyloxy)phosphoryl)oxy)methoxy)-9-ethyl-5-fluoro-4- methyl-10,13-dioxo-2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2- b]quinolin-1-yl)carbamate (13). To a mixture of compound 12 (146 mg, 0.25 mmol) in THF (3 mL) was added molecular sieves (500 mg), followed by the addition of NIS (164 mg, 0.73mmol) and dibenzyl phosphate (204 mg, 0.73 mmol) at 0 °C. The mixture was stirred at 0 °C and warmed gradually to room temperature over 2.5 to 3 h, while covered with aluminum foil to prevent undesired reactions upon light exposure. Upon confirming the completion of reaction via TLC and LCMS (Method 7), the reaction was quenched with saturated sodium thiosulfate (5 mL), in which there was a color change from brown to yellow. The mixture was then extracted with EtOAc (3 × 10mL). The combined organic layers were dried over magnesium sulfate, filtered and solvent was removed under rotary evaporator. The crude product was purified via combi-flash, and target compound 13 was eluted at 6% MeOH/DCM to give pure product (128 mg, 62% yield). LCMS (Method 7) Calculated for C44H46FN3O10P (M+H)+ = 826.3; observed 826.0. WSGR Ref. No: 31362-826.601
Figure imgf000178_0001
. tert-Butyl ((1S,9S)-9-ethyl-5-fluoro-4-methyl-10,13-dioxo-9-((phosphonooxy)methoxy)- 2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1- yl)carbamate (14). To a mixture of compound 13 (244 mg, 0.29 mmol) in 10 mL THF and 500 µL water was added 10% Pd/C (~244 mg, 1 eq). The mixture was stirred at room temperature for 0.5 h, in which the desired product was formed as indicated by LCMS (Method 7) The mixture was then filtered over a pad of celite. Solvent was removed under reduced pressure, and pale-yellow pure compound 14 obtained (120 mg, 0.185 mmol, 66% yield) and stored at -20 °C before being used in the coupling reaction. LCMS (Method 7) Calculated for C30H34FN3O10P (M+H)+ = 646.2; observed 646.0.
Figure imgf000178_0002
. tert-Butyl ((1S,9S)-9-((((((2-(((tert-butoxycarbonyl)amino)oxy)ethoxy)(hydroxy)- phosphoryl)oxy)(hydroxy)phosphoryl)oxy)methoxy)-9-ethyl-5-fluoro-4-methyl-10,13-dioxo- 2,3,9,10,13,15-hexahydro-1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-1- yl)carbamate (15). To a mixture of compound 14 (79 mg, 0.122 mmol) in DMF (2 mL) was added CDI (48 mg, 0.29 mmol) and Et3N (17.0 µL, 0.122 mmol). The mixture was stirred at room temperature over 2.5 to 3 h. LCMS (Method 8) showed the formation of the desired intermediate. Then, compound 8 (94 mg, 0.366 mmol) was added followed by the addition of ZnCl2 (100 mg, WSGR Ref. No: 31362-826.601 0.732 mmol) and the mixture was stirred for additional 18 hours. After that, product formation as well as some exatecan dimer formation were detected. The mixture was quenched by evaporating the DMF using rotary evaporator while heating at 45 °C. The crude compound 15 was then used immediately for Boc-deprotection without any further purification. LCMS (Method 8) Calculated for C37H48FN4O16P2 (M+H)+ = 885.2; observed 885.0; C37H46FN4O16P2 (M-H)- = 883.2; observed 883.0.
Figure imgf000179_0001
[[(10S,23S)-23-Amino-10-ethyl-18-fluoro-19-methyl-5,9-dioxo-8-oxa-4,15- diazahexacyclo[14.7.1.02,14.04,13.06,11.020,24]tetracosa-1,6(11),12,14,16,18,20(24)-heptaen-10- yl]oxymethoxy-hydroxy-phosphoryl] 2-aminooxyethyl hydrogen phosphate (16). Crude compound 15 was dissolved in DCM (1 mL) and TFA (1 mL) at room temperature, and the mixture was stirred at room temperature for 30 mins. LCMS (Method 8) showed product formation, so solvent was removed under rotary evaporator, and the mixture was resuspended in 3 mL DMSO and 500 µL of 10 mM ammonium bicarbonate. Then the crude product was purified via semi-preparative HPLC, where pure product was eluted at 40-50% (95% ACN, and 5% 10 mM of ammonium bicarbonate)/(10 mM ammonium bicarbonate). Pure fractions were combined and lyophilized over the weekend to give pure compound 16 as a white solid (7.3 mg, 8.7 % over 2 steps). LCMS (Method 8) Calculated for C27H32FN4O12P2 (M+H)+ = 685.1; observed 685.0; C27H30FN4O12P2 (M-H)- = 683.1; observed 683.0. WSGR Ref. No: 31362-826.601
Figure imgf000180_0001
Example 4: Synthesis of compounds 17, 18 and 19. (((1S,9S)-1-Amino-9-ethyl-5-fluoro-4-methyl-10,13-dioxo-2,3,9,10,13,15-hexahydro- 1H,12H-benzo[de]pyrano[3',4':6,7]indolizino[1,2-b]quinolin-9-yl)oxy)methyl dihydrogen phosphate (17). The Boc group can be removed from compound 14 according to methods known to a person of ordinary skill in the art (e.g., with TFA in DCM or with HCl in methanol) to provide compound 17 having the following structure:
Figure imgf000180_0002
. [[2-[[4-(2-Aminooxyethoxy)-6-[2-[[[(10S,23S)-10-ethyl-18-fluoro-10-hydroxy-19-methyl- 5,9-dioxo-8-oxa-4,15-diazahexacyclo[14.7.1.02,14.04,13.06,11.020,24]tetracosa- 1,6(11),12,14,16,18,20(24)-heptaen-23-yl]carbamoyloxymethoxy-hydroxy-phosphoryl]oxy- hydroxy-phosphoryl]oxyethoxy]-1,3,5-triazin-2-yl]oxy]ethoxy-hydroxy-phosphoryl]oxy-hydroxy- phosphoryl]oxymethyl N-[(10S,23S)-10-ethyl-18-fluoro-10-hydroxy-19-methyl-5,9-dioxo-8-oxa- 4,15-diazahexacyclo[14.7.1.02,14.04,13.06,11.020,24]tetracosa-1,6(11),12,14,16,18,20(24)-heptaen-23- yl]carbamate (18). Compound 18 can be synthesized according to the following scheme: WSGR Ref. No: 31362-826.601
Figure imgf000181_0001
[[[3-[(2-Aminooxyacetyl)amino]-5-[[[(10S,23S)-10-ethyl-18-fluoro-10-hydroxy-19-methyl- 5,9-dioxo-8-oxa-4,15-diazahexacyclo[14.7.1.02,14.04,13.06,11.020,24]tetracosa- 1,6(11),12,14,16,18,20(24)-heptaen-23-yl]carbamoyloxymethoxy-hydroxy-phosphoryl]oxy- hydroxy-phosphoryl]oxy-phenoxy]-hydroxy-phosphoryl]oxy-hydroxy-phosphoryl]oxymethyl N- [(10S,23S)-10-ethyl-18-fluoro-10-hydroxy-19-methyl-5,9-dioxo-8-oxa-4,15- diazahexacyclo[14.7.1.02,14.04,13.06,11.020,24]tetracosa-1,6(11),12,14,16,18,20(24)-heptaen-23- yl]carbamate (19). Compound 19 can be synthesized according to the following scheme:
Figure imgf000181_0002
WSGR Ref. No: 31362-826.601
Figure imgf000182_0001
Example 5: Site Specific Conjugation of Drug-Linkers The synthesized drug-linker compounds generated by the above schemes are utilized in engineering ADCs. Briefly, anti-TROP2, anti-CD70, anti-HER2, anti-PSMA or anti-HER3 antibodies, each containing non-natural amino acid para-acetyl-L-phenylalanine (pAF) on heavy chains at amino acid position 114, are buffer exchanged into 30 mM sodium acetate; 2.5% trehalose, pH 4.0-4.3 and concentrated to 10-20 mg/mL. Acetic hydrazide (100mM) and amino-oxy functionalized drug-linker compounds 10 and 16 (10-25 molar equivalents) are added and reacted for 16-48 hours at 30 °C. The resulting ADCs are purified over a cation exchange column (Capto SP Impres, Cytiva) to remove excess reagents. The purified ADCs are buffer exchanged into until further use. Exemplary ADCs comprising Compounds 10 or 16 are illustrated below. Scheme showing exemplary ADCs engineered by conjugating Compound 10 with anti- TROP2, anti-CD70, anti-HER2, anti-PSMA or anti-HER3 mAb comprising non-natural amino acid pAF:
Figure imgf000182_0002
Scheme showing exemplary ADCs engineered by conjugating Compound 16 with anti- TROP2, anti-CD70, anti-HER2, anti-PSMA or anti-HER3 mAb comprising non-natural amino acid pAF: WSGR Ref. No: 31362-826.601
Figure imgf000183_0001
ADCs containing anti-HER3 antibody conjugated to Compound 10 or 16 (DAR > 3): Anti-HER3 antibodies containing non-natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 58; Table 5) and Kabat position 121 of each light chain (SEQ ID NO: 51; Table 5) were buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide was added to the antibodies followed by 10-25 molar equivalents of compound 10, and, in a separate experiment, compound 16. The conjugation reactions were incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (GE Healthcare) to remove excess reagents. The purified ADCs were of each ADC was recorded at two different wavelengths using a Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compounds 10 and 16 were used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for each conjugate was obtained from the ratio of these values: anti-HER3- HA114/LS121-Compound-10, DAR: 3.56; anti-HER3-HA114/LS121-Compound-16, DAR: 3.11. ADCs containing anti-TROP2 antibody conjugated to Compound 10 (DAR > 3): Anti-TROP2 antibody containing non-natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 5; Table 1) and Kabat position 121 of each light chain (SEQ ID NO: 11; Table 1) were buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide was added to the antibodies followed by 10-25 molar equivalents of compound 10. The conjugation reaction was incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (Cytiva) to remove excess reagents. The purified ADC was buffer exchanged into pH 6.0 histidine buffer and stored at using a Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compound 10 was used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for the conjugate was obtained from the ratio of these values: anti-TROP2-HA114/LS121-Compound-10, DAR: 3.76. Anti-TROP2 antibody containing non- WSGR Ref. No: 31362-826.601 natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 5; Table 1) and Kabat position 121 of each light chain (SEQ ID NO: 11; Table 1) is conjugated to compound 16 as described above. ADCs containing anti-CD70 antibody conjugated to Compound 10 or 16: Anti-CD70 antibody containing non-natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 20; Table 2) and Kabat position 121 of each light chain (SEQ ID NO: 24; Table 2) is conjugated to compound 10 or compound 16 using the protocol as described above for anti-HER3 or anti-TROP2. Generally, the antibody is buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide is added to the antibodies followed by 10-25 molar equivalents of compound 10 or compound 16. The conjugation reaction is incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (Cytiva) to remove excess reagents. The purified ADC is buffer exchanged recorded at two different wavelengths using Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compound 10 or compound 16 are used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for the conjugate is obtained. ADCs containing anti-HER2 antibody conjugated to Compound 10 or 16: Anti-HER2 antibody containing non-natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 26; Table 3) and Kabat position 121 of each light chain (SEQ ID NO: 28; Table 3) is conjugated to compound 10 or compound 16 using the protocol as described above for anti-HER3 or anti-TROP2. Generally, the antibody is buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide is added to the antibodies followed by 10-25 molar equivalents of compound 10 or compound 16. The conjugation reaction is incubated for 18-24 hours at 25-30 °C, followed by purification over a Capto SP Impres column (Cytiva) to remove excess reagents. The purified ADC is buffer exchanged recorded at two different wavelengths using Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compound 10 or compound 16 are used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for the conjugate is obtained. ADCs containing anti-PSMA antibody conjugated to Compound 10 or 16: Anti-PSMA antibody containing non-natural amino acid pAF at Kabat position 114 of each heavy chain (SEQ ID NO: 36; Table 4) and Kabat position 121 of each light chain (SEQ ID NO: 37; Table WSGR Ref. No: 31362-826.601 4) can be generated following the steps of described for anti-HER3 or anti-TROP2 described above. Generally, the antibody is buffer exchanged into conjugation buffer (30 mM sodium acetate, pH 4.0) and concentrated to 10-20 mg/mL. A final of 100 mM acetic hydrazide is added to the antibodies followed by 10-25 molar equivalents of compound 10 or compound 16. The conjugation reaction is incubated for 18-48 hours at 25-30 °C, followed by purification over a Capto SP Impres column (Cytiva) to remove excess reagents. The purified ADC is buffer exchanged into pH 6.0 histidine wavelengths using Nanodrop 2000C (Thermo Scientific). Molar extinction coefficients at each wavelength for the antibody and for drug-linker compound 10 or compound 16 are used to determine mAb and drug concentrations, and the drug-antibody ratio (DAR) for the conjugate is obtained. Example 6: Molecular Cloning for expression of anti-HER3 and anti-TROP2 antibodies Molecular cloning for expression of exemplary anti-HER3 antibodies and anti-TROP2 antibodies is described below. This protocol is applicable to anti-CD70 antibodies, anti-HER2 antibodies, and anti-PSMA antibodies. Molecular Cloning for Antibody Expression - CHO cell codon-optimized antibody heavy chain and light chain cDNA sequences were obtained from a commercial DNA synthesis service (Integrated DNA Technologies (IDT), San Diego, CA). The synthesized DNA fragments were digested with Hind III and EcoR I (both from New England BioLabs, (NEB), Ipswich, MA) and purified using a PCR purification kit (Qiagen, Valencia, CA). Then the digested antibody gene fragments were ligated into the expression vector via a quick ligation kit (NEB) to yield the constructs for expression of wild type antibody heavy chain and light chain. The resulting plasmids were propagated in E. coli and verified by a DNA sequencing service (Eton Biosciences, San Diego, CA). Generation of amber codon-containing mutants - Based on the crystal structure of anti-HER2 Fab, ten different surface-accessible sites located at light chain constant region were chosen to genetically incorporate non-natural amino acid (e.g., pAF). Those sites are not critical for antigen- antibody binding. Each genetic codon of the chosen site was then mutated to amber codon (TAG) via site-directed mutagenesis to generate expression plasmid for that antibody mutant. Primers were purchased from IDT. All site directed mutagenesis experiments were carried out using Q5 site- directed mutagenesis kit following instruction manuals (NEB). The expression plasmids for the mutants were propagated in E. coli and verified by DNA sequencing service (Eton Biosciences). The non-natural amino acid is site specifically incorporated at any one of positions A121 (A114) in the heavy chain and in any one of the positions V110, A112, S114, S121, S127, K149, S156, S168, S202 and V205 in the light chain (position are according to Kabat numbering, as well known to the skilled artisan), Table 10. WSGR Ref. No: 31362-826.601 Table 10. List of IgG1 light chain (LC) constant region amber mutation sites (Kabat numbering).
Figure imgf000186_0001
Example 7: Protocols for Production of Antibodies Containing pAF Methods of generating cell lines to promote non-natural amino acid-containing protein production using genome engineering technology, are described in WO2018/223108, the entire contents of which are hereby incorporated by reference in their entirety, can be applied to generate antibodies of the present disclosure including exemplary anti-HER3 antibodies and anti-TROP2 antibodies, and including anti-CD70 antibodies, anti-HER2 antibodies, and anti-PSMA antibodies, containing non-naturally encoded amino acids. Production of antibodies containing pAF, disclosed herein, can be performed using transient expression, stable pool generation, and Fed-batch expression as described below. Production of antibodies of the invention include anti-HER3 antibodies, anti-TROP2 antibodies, anti-CD70 antibodies, anti-HER2 antibodies, and anti-PSMA antibodies each containing pAF. Transient expression - Platform cell line was maintained in EX-CELL 302 (Sigma) supplemented with 3 mM L-glutamine (Gibco) and 3 mM GlutaMAX (Gibco). Cells were passaged every 3 to 4 days seeded at a density of 0.4 million cells per ml. One day prior to transfection, cells were seeded at 0.6 million cells per ml. On day 0, cells were transfected with antibody expression plasmids encoding the light chain and heavy chain using MaxCyte electroporation platform following the instruction manual. After transfection, cells were rested in an empty 125 ml shake flask and incubated at 37 °C in a static incubator for 30 min. Basal expression media (50% Dynamis : 50% EX-CELL 302 supplemented with 3 mM L-glutamine and 3 mM GlutaMAX) was added to the transfected cells in the shake flask for a final density of 3 x 106 cells per ml. The transfected cells were incubated at 37 °C, 5% CO2 on an orbital shaker set to 155 RPM. The following were added to the culture on day 1: pAF (final concentration in culture: 1 mM), Cell Boost 4 (GE Healthcare; final concentration in culture: 3.75 g/L), Cell Boost 7b (GE Healthcare; final concentration in culture: WSGR Ref. No: 31362-826.601 0.2 g/L), Long R3 IGF-1 (Sigma; final concentration in culture: 120 µg/L) and GlutaMAX (final concentration in culture: 2 mM). The incubator temperature was shifted from 37 °C to 32 °C. Additional Cell Boost 4 (final concentration: 2 g/L), Cell Boost 7b (final concentration: 0.1 g/L), and GlutaMAX (final concentration: 2 mM) was added on days 3 and 5, and supernatant was collected on day 7. The culture media glucose level was monitored using glucose meters, and additional glucose was added to the culture when the glucose level was below 2 g/L. Viable cell count and viability were measured by Vi-Cell instrument. Antibody production was measured by Octet using Protein G sensors. Stable bulk pool generation - The expression plasmid was linearized using Pvu I (NEB) digestion for four hours. After linearization, the DNA was purified using phenol:chloroform:isoamyl alcohol extraction and dissolved in endotoxin-free water at the concentration of 2.5 µg/µl. Platform cell line 301-20 was maintained in EX-CELL 302 supplemented with 3 mM L-glutamine and 3 mM GlutaMAX. Cells were passaged every 3 to 4 days seeded at a density of 0.3 x 106/ml. One day prior to transfection, cells were seeded at 0.6 x 106/ml. On day 0, 15 x 106 cells were transfected with 25 µg of linearized antibody expression plasmids using MaxCyte electroporation (OC-100) platform following the instruction manual. After transfection, cells were rested in an empty 125 ml shake flask and incubated at 37 °C in a static incubator for 30 min. Then 30 ml recovery media (50% EX-CELL: 50% CD-CHO supplemented with 3 mM L-glutamine and 3mM GlutaMAX) was added into the flask and shaken overnight. On day one, transfected cells were counted, spun down, washed and re- suspended in selection media (50% EX-CELL 302 : 50% CD-CHO with 25 µM MSX) for stable bulk pool generation. The viable cell numbers and viability were monitored, and media was changed every 3 to 4 days until the viability of the stable bulk pool returned to 90%. When selection ended, frozen cell stocks were made, and the resulting stable bulk pool was used to generate material for fed-batch expression. Fed-batch expression - Previously generated antibody stable bulk pools were inoculated into basal expression media (50% Dynamis : 50% EX-CELL 302 supplemented with 1x GS, 2 µg/ml insulin, 0.5 mM ornithine, 2 g/L glucose and 1 x anti clumping agent and 25 µM MSX) at a density of 0.5 x 106/ml in a shake flask on day 0. The transfected cells were incubated at 37 °C, 5% CO2 on an orbital shaker set to 150 rpm. The following were added to the culture on day 3: pAF (final concentration in culture: 0.5 mM), Cell Boost 4 (GE Healthcare; final concentration in culture: 10 g/L) and Cell Boost 7b (GE Healthcare; final concentration in culture: 0.52 g/L). Long R3 IGF-1 (final concentration in culture: 120 µg/L) was added to the culture on day 5. The culture media glucose level was monitored using glucose meters, and additional glucose was added to the culture up to 6g/L when the glucose level was below 2 g/L. Viable cell count and viability were measured WSGR Ref. No: 31362-826.601 by Vi-Cell instrument. The supernatant was collected for purification on day 10. Antibody production was measured by Octet using Protein G sensors. Example 8: Purification of Antibodies from EuCODE Expression System Clarified Cell culture media containing the target antibody containing non-natural amino acid pAF was loaded over a protein A MabSelect PrismA column (Cytiva) equilibrated in 20 mM sodium phosphate, 100 mM sodium chloride, pH 7.5. After loading, the column was washed with buffer A (20 mM sodium phosphate, 100mM sodium chloride, pH 7.5) followed by wash buffer B (50 mM sodium acetate, pH 5.5) to remove host cell contaminants. The target antibody was eluted from the column with elution buffer C (50 mM sodium acetate, pH 3.8). The target antibody was pooled, and pH adjusted to pH 5.0 with 2.0 M tris base. The target antibody was further purified by loading the conditioned protein A pool over a Capto SP Impres column (Cytiva) equilibrated in 50 mM sodium acetate, pH 5.0. The target antibody was eluted from the column with a linear gradient to 100% buffer B (50 mM sodium acetate, 0.5 M sodium chloride, pH 5.0) and fractions containing Example 9: TROP2 cell surface expression TROP2 cell surface levels were quantified using the Dako QIFIKIT (Agilent, Santa Clara, CA) according to the manufacturer’s instruction. Briefly, cells were harvested using StemPro Acccutase cell dissociation reagent, washed with FACS buffer (1x PBS containing 0.2% BSA and 15 mM NaN3), and incubated with mouse anti-TROP2 antibody (clone MR54, eBioScience, San Diego, CA) or isotype control antibody (mouse IgG2a, kappa, eBioScience). After washing, FITC conjugated anti-mouse secondary antibody provided by kit was incubated with cells, set-up beads, and calibration beads. Washed cells and beads were run on FACSCantoII. Lot specific calibration beads were used to generate a standard curve to calculate TROP2 number on the surface of each cell line. TROP2 cell surface numbers were determined as shown in Table 11. Table 11. TROP2 expression level on various cancer cell lines
Figure imgf000188_0001
WSGR Ref. No: 31362-826.601
Figure imgf000189_0001
Example 10: HER3 cell surface expression HER3 surface levels were quantified using the Dako QIFIKIT (Agilent, Santa Clara, CA) according to the manufacturer’s instructions. Cells were incubated with mouse anti-HER3 antibody (BioLegend, San Diego, CA, Cat#324702) or isotype control antibody and detected with FITC conjugated anti-mouse secondary antibody provided by the kit. The calibration beads were used to generate a standard curve to calculate the surface HER3 numbers on the cells (Table 12). Table 12. HER3 Expression level on various cancer cell lines
Figure imgf000189_0002
Example 11: In vitro cytotoxicity of ADCs containing anti-HER3 antibody conjugated to compound 10 or 16 (DAR > 3). ADCs anti-HER3-HA114/LS121-Compound-10 and anti-HER3-HA114/LS121-Compound- 16, each prepared as described in Example 5, were evaluated for cytotoxicity in a 3-D culture cytotoxicity assay. Briefly, cells were seeded at 1,000 cells/well into 96-well clear round bottom ultra-low attachment microplate and cultured for 3 days in a 37 °C and 5% CO2 incubator. Serially diluted anti-HER3 ADCs (anti-HER3-HA114/LS121-Compound-10, anti-HER3-HA114/LS121- Compound-16 and anti-HER3-DAR8-Dxd (anti-HER3 antibody containing eight Dxd payloads per antibody)) and unconjugated drugs (exatecan mesylate and Dxd (CAS 159944-33-1, commercially available from MedChemExpress, Catalog No.: HY-13631D) were added to the wells and the plates WSGR Ref. No: 31362-826.601 were incubated for 7 days. At the end of incubation, CellTiter-Glo 3D Reagent (Promega, Madison, WI) was added to the room temperature equilibrated plates, mixed for 5 minutes, and allowed the luminescent signal stabilized for 25 minutes. The media were transferred to new 96-well white flat- bottom plates and luminescence was measured in a SpectraMax M5E luminometer. The relative viability of each cell line was calculated based on untreated cells as 100% viability. The half-maximal effective concentration (EC50) was determined by a nonlinear 4-parameter dose-response curve fitting using GraphPad Prism (GraphPad Software, San Diego, CA). The maximal killing (Emax) was determined by subtracting the % viability from 100%. The results are shown in FIGS.1 to 4 and summarized in Tables 13 to 16 below. Table 13. EC50 (nM) and Emax (%) in HCC1569 cell line in 3D culture system.
Figure imgf000190_0001
Table 14. EC50 (nM) and Emax (%) in A375 cell line in 3D culture system.
Figure imgf000190_0002
Table 15. EC50 (nM) and Emax (%) in HCC827 cell line in 3D culture system.
Figure imgf000190_0003
WSGR Ref. No: 31362-826.601 Table 16. EC50 (nM) and Emax (%) in exatecan-sensitive/HER3-negative Calu-6 cell line in 3D culture system.
Figure imgf000191_0001
Example 12: In vitro cytotoxicity of ADCs containing anti-TROP2 antibody conjugated to compound 10 (DAR > 3) in multiple cancer cell lines. Cytotoxicity of anti-TROP2- HA114/LS121-Compound-10 was tested in multiple cancer cell lines with various TROP2 surface expression levels. Cells were seeded into 96-well clear bottom white wall plate at 2,500 cells/well for BxPC-3, MDA-MB-468, and Calu-6 cells, or at 2,000 cells/well for HCC1806 cells and incubated overnight in a 37 °C, 5% CO2 incubator. The next day serially diluted anti-TROP2-HA114/LS121-Compound- 10 or Exatecan mesylate was added to the wells, and the plates were incubated for 7 days. At the end of incubation, luminescence was measured by the addition of CellTiter-Glo2.0 Reagent (Promega, Madison, WI) to the room-temperature equilibrated plates. The relative cell viability was calculated as a percentage of untreated control. The half-maximal inhibitory concentration (IC50) was determined by a nonlinear 4-parameter dose-response curve fitting using GraphPad Prism (GraphPad Software, San Diego, CA). The maximal killing (Emax) was determined by subtracting the % viability from 100%. The IC50 values of anti-TROP2-HA114/LS121-Compound-10 were in the range of 0.33-1.73 nM in TROP2-expressing BxPC-3, MDA-MB-468 and HCC1806 cell lines after 7 days of treatment; the IC50 of anti-TROP2-HA114/LS121-Compound-10 in the TROP2-negative Calu-6 cell line was 17.58 nM (see Table 17 and FIGS.5A-5D). Table 17. IC50 (nM) and Emax (%) at 100 nM of anti-TROP2-HA114/LS121-Compound-10 in Multiple Cancer Cell Lines
Figure imgf000191_0002
WSGR Ref. No: 31362-826.601
Figure imgf000192_0002
Example 13: In vitro Cytotoxicity of anti-TROP2-HA114/LS121-Compound-10 in Human Keratinocytes. Primary human keratinocytes (ATCC, Cat# PCS-200-011) were maintained in Dermal Cell Basal Medium (ATCC, Cat# PCS-200-030) supplemented with Keratinocyte Growth Kit (ATCC, Cat# PCS-200-400). Keratinocytes were seeded at 4,000 cells/well into 96-well clear bottom white wall plate and incubated overnight in a 37 °C, 5% CO2 incubator. The next day, cells were treated with serially diluted anti-TROP2-HA114/LS121-Compound-10 or Exatecan mesylate for 7 days. The relative viability of the cells was measured using CellTiter-Glo2.0 Reagent and the results are shown in FIG.6. Anti-TROP2-HA114/LS121-Compound-10 showed an IC50 value of 13.55 nM against TROP2- expressing human keratinocytes; the Emax was 60.40% when cells were treated with the ADC at a concentration of 100 nM. Example 14: Anti-CD70, Anti-HER2 and Anti-PSMA Antibodies and Variants Thereof, and ADCs. Anti-CD70, anti-HER2 and anti-PSMA antibodies and variants thereof of the present disclosure, and ADCs of the present disclosure containing said antibodies and variants thereof, can be prepared as described in WO2013/192360A1, WO2022/212899A1 and WO2019/191728A1, the entire contents of each of which are hereby incorporated by reference in their entirety, and/or by adapting methods expressly disclosed herein. Non-limiting Numbered Embodiments of the invention are listed below. A1. An antibody-drug conjugate (ADC) of Formula (I):
Figure imgf000192_0001
wherein Drug has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000193_0001
each n is independently 1 or 2; p is 1, 2, 3, 4, 5, 6, 7 or 8; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , C3-C6 cyclic alkylene, * (OCH2CH2)m , unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1- C3 alkoxy; wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5 or 6; each L2 is independently absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6 and each j is independently 0, 1, 2, 3, 4, 5 or 6; and each L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, each q is independently 1, 2, 3, 4, 5 or 6 and each r is independently 1, 2, 3, 4, 5 or 6; or L2b is selected from the group consisting of: WSGR Ref. No: 31362-826.601
Figure imgf000194_0003
wherein [**] denotes connection to Ab and each s is 1, 2, 3, 4, 5, or 6; or each L3 independently comprises a MC (6-maleimidocaproyl), a MCC (a maleimidomethyl cyclohexane-1-carboxylate), a MP (maleimidopropanoyl), a PAB (p-aminobenzyloxycarbonyl), a SPP (N-Succinimidyl 4-(2-pyridylthio) pentanoate), a SMCC (N-Succinimidyl 4-(N- maleimidomethyl)cyclohexane-1 carboxylate), or a SIAB (N-Succinimidyl (4-iodo- acetyl)aminobenzoate); each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O-
Figure imgf000194_0001
(CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; and Ab is an antibody, antibody fragment or variant thereof. A2. The ADC of embodiment A1, wherein Drug has the following structure:
Figure imgf000194_0002
. A3. The ADC of embodiment A1, wherein Drug has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000195_0001
. A4. The ADC of any one of embodiments A1 to A3, wherein the antibody, antibody fragment or variant thereof comprises one or more non-natural amino acids. A5. The ADC of any one of embodiments A1 to A4, wherein the antibody, antibody fragment or variant thereof is configured to bind to an antigen. A6. The ADC of any one of embodiments A1 to A5, wherein the antibody, antibody fragment or variant thereof is configured to bind to a tumor-associated antigen (TAA) or cancer antigen. A7. The ADC of any one of embodiments A1 to A6, wherein the antibody, antibody fragment or variant thereof binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA-125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha and MN/CA IX. A8. The ADC of any one of embodiments A1 to A6, wherein Ab comprises a heavy chain having a heavy chain sequence, a light chain having a light chain sequence, or both. A9. The ADC of embodiment A8, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids. A10. The ADC of embodiment A8 or A9, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids. A11. The ADC of any one of embodiments A1 to A10, wherein Ab comprises two heavy chains, each heavy chain having a heavy chain sequence, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acid. WSGR Ref. No: 31362-826.601 A12. The ADC of any one of embodiments A1 to A11, wherein Ab comprises two light chains, each light chain having a light chain sequence, wherein each light chain sequence comprises at least one of the one or more non-natural amino acid; optionally, wherein Ab comprises two heavy chains and two light chains, wherein each heavy chain sequence and each light chain sequence comprises at least one of the one or more non-natural amino acid. A13. The ADC of any one of embodiments A4 to A12, wherein each of the one or more non-natural amino acids, is independently selected from the group consisting of para-acetyl phenylalanine, 4- acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)), 3-O-(N-acetyl-beta-D-glucosaminyl)- acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L- tyrosine, 3-amino-L-tyrosine, 4-azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin- 5yl)-L-alanine, 3-borono-L-phenylalanine, 4-borono-L-phenylalanine, 4-bromo-L-phenylalanine, p- carboxymethyl-L-phenylalanine, 4-carboxy-L-phenylalanine, p-cyano-L-phenylalanine, 3,4- dihydroxy-L-phenylalanine (L-DOPA), 4-ethynyl-L-phenylalanine, 2-fluoro-L-phenylalanine, 3- fluoro-L-phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl-beta-D- galactosaminyl)-L-serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L- phenylalanine, 4-isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O- mannopyranosyl-L-serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L- phenylalanine, 3-methyl-L-phenylalanine, O-methyl-L-tyrosine, 3-(2-naphthyl)-L-alanine, 5-nitro- L-histidine, 4-nitro-L-histidine, 4-nitro-L-leucine, 2-nitro-L-phenylalanine, 3-nitro-L-phenylalanine, 4-nitro-L-phenylalanine, 4-nitro-L-tryptophan, 5-nitro-L-tryptophan, 6-nitro-L-tryptophan, 7-nitro- L-tryptophan, 2-nitro-L-tyrosine, 3-nitro-L-tyrosine, O-phospho-L-serine, O-phospho-L-tyrosine, 4- propargyloxy-L-phenylalanine, O-2-propyn-1-yl-L-tyrosine, 4-sulfo-L-phenylalanine and O-sulfo- L-tyrosine. A14. The ADC of any one of embodiments A1 to A13, wherein Ab is conjugated to the terminal arm of L3 via an oxime bond. A15. The ADC of any one of embodiments A4 to A14, wherein at least one of the non-naturally occurring amino acids is para-acetyl phenylalanine; optionally, wherein at least one of the non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)). A16. The ADC of any one of embodiments A4 to A15, wherein each of the one or more non-natural amino acids is the same. WSGR Ref. No: 31362-826.601 A17. The ADC of embodiment A16, wherein each of the one or more non-natural amino acids is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L- phenylalanine (para-acetyl-L-phenylalanine (pAF)). A18. The ADC of any one of embodiments A1 to A17, wherein the antibody, antibody fragment or variant thereof comprises 1, 2, 3 or 4 non-natural amino acids. A19. The ADC of any one of embodiments A1 to A18, wherein Ab is an anti-trophoblast antigen 2 (anti-TROP2) antibody. A20. The ADC of embodiment A19, wherein the anti-TROP2 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17 (Table 1). A21. The ADC of embodiment A20, wherein the anti-TROP2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 5, and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. A22. The ADC of embodiment A21, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1 and 2, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. A23. The ADC of embodiment A21, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 5 and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. A24. The ADC of embodiment A21, A22 or A23, wherein the heavy chain sequence comprises at least one non-natural amino acid. A25. The ADC of any one of embodiments A1 to A18, wherein Ab is an anti-CD70 antibody. A26. The ADC of embodiment A25, wherein the anti-CD70 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 18, 19, 20, 21, 22, 23 and 24 (Table 2). A27. The ADC of embodiment A26, wherein the anti-CD70 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 18 and 20, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. A28. The ADC of any one of embodiments A1 to A18, wherein Ab is an anti-HER2 antibody. WSGR Ref. No: 31362-826.601 A29. The ADC of embodiment A28, wherein the anti-HER2 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 25, 26, 27 and 28 (Table 3). A30. The ADC of embodiment A29, wherein the anti-HER2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 25 and 26, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 27 and 28. A31. The ADC of any one of embodiments A1 to A18, wherein Ab is an anti-PSMA antibody. A32. The ADC of embodiment A31, wherein the anti-PSMA antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 and 45 (Table 4). A33. The ADC of embodiment A32, wherein the anti-PSMA antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 29, 34, 36, 38, 40, 42 and 44 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45. A34. The ADC of embodiment A33, wherein the heavy chain sequence comprises an amino acid of SEQ ID No: 36, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45. A35. The ADC of embodiment A34, wherein the heavy chain sequence comprises an amino acid of SEQ ID No: 36, and wherein the light chain sequence comprises an amino acid sequence of SEQ ID NO: 37. A36. The ADC of any one of embodiments A1 to A28, wherein Ab is an anti-HER3 antibody. A37. The ADC of embodiment A37, wherein the anti-HER3 antibody comprises a sequence selected from the group consisting of SEQ ID NO: 46 to 58 (Table 5). A38. The ADC of embodiment A37, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 46 or 58 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57. A39. The ADC of embodiment A37, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57. WSGR Ref. No: 31362-826.601 A40. The ADC of any one of embodiments A36 to A39, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and the light chain sequence comprises an amino acid sequence of SEQ ID NO: 50. A41. The ADC of embodiment A40, wherein the anti-HER3 antibody comprises two heavy chain sequences and two light chain sequences, wherein each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 50. A42. The ADC of embodiment A40 or A41, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 50. A43. The ADC of any one of embodiments A36 to A39, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and the light chain sequence comprises an amino acid sequence of SEQ ID NO: 51. A44. The ADC of embodiment A43, wherein the anti-HER3 antibody comprises two heavy chain sequences and two light chain sequences, wherein each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 51. A45. The ADC of embodiment A43 or A44, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 51. A46. A pharmaceutical composition comprising an ADC of any one of embodiments A1 to A45 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. B1. An antibody-drug conjugate (ADC) of Formula (V) or (VI):
Figure imgf000199_0001
WSGR Ref. No: 31362-826.601 Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids; L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof. B2. The ADC of embodiment B1, wherein the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. B3. The ADC of embodiment B1 or B2, wherein L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(Rw)-, , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl; optionally, each arylene is phenyl. B4. The ADC of embodiment B1, B2 or B3, wherein E comprises an amide, an ester, a thioester, a pyrrolidine-2,5-dione, an oxime, a 4,5-dihydro-1,2,3-triazole or a 1,4-dihydropyridazine, wherein the 4,5-dihydro-1,2,3-triazole or 1,4-dihydropyridazine is optionally fused to an 8-membered ring; optionally, E comprises an oxime. B5. The ADC of any one of embodiments B1 to B4, wherein the antibody, antibody fragment or variant thereof binds to an antigen selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, PD-I, PDL-1, VEGFR, EGFR, c-Met (HGFR), CD19, CD22, CD24, CD25 (IL-2R alpha), CD30, CD33, CD37, CD38, CD44, CD46, CD47, CD48, CD52, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD96, CD97, CD99, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD179, CD203c (ENPP3), TIMI, CD205 (LY75), CD221 (IGF-1R), CD223, CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, MUCI, MUC16 (CA-125), WSGR Ref. No: 31362-826.601 GPC3, CEA, CEACAM5, CEACAM6, CA9, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, FOLR1 (folate receptor alpha), Tissue Factor (TF), CA6, BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, Cadherin 6, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, SLC34A2, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, SLITRK6, AXL, LAMP1, LRRC15, TNF-alpha, CTLA-4 and MN/CA IX. B6. The ADC of any one of embodiments B1 to B5, wherein Ab comprises a heavy chain having a heavy chain sequence, a light chain having a light chain sequence, or both. B7. The ADC of embodiment B6, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids. B8. The ADC of embodiment B6 or B7, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids. B9. The ADC of any one of embodiments B1 to B8, wherein Ab comprises two heavy chains, each heavy chain having a heavy chain sequence, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acid. B10. The ADC of any one of embodiments B1 to B9, wherein Ab comprises two light chains, each light chain having a light chain sequence, wherein each light chain sequence comprises at least one of the one or more non-natural amino acid. B11. The ADC of embodiment B10, wherein Ab comprises two heavy chains and two light chains, wherein each heavy chain sequence and each light chain sequence comprises at least one of the one or more non-natural amino acid. B12. The ADC of any one of embodiments B1 to B11, wherein E is selected from the group consisting of:
Figure imgf000201_0001
WSGR Ref. No: 31362-826.601
Figure imgf000202_0001
wherein: each Rb is independently H or unsubstituted C1-C6 alkyl; each Rc is independently unsubstituted C1-C6 alkyl; each Rf is independently H or unsubstituted C1-C6 alkyl, each s is independently 0, 1, 2, 3, 4, 5 or 6, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to L; and each wavy line denotes connection to the Ab. B13. The ADC of any one of embodiments B1 to B12, wherein E is:
Figure imgf000202_0002
wherein Rc is unsubstituted C1-C6 alkyl; optionally, Rc is methyl. B14. The ADC of any one of embodiments B1 to B13, wherein Ab binds to an antigen selected from the group consisting of PSMA, CD70, CD3, HER2, HER3 and TROP2. B15. The ADC of any one of embodiments B1 to B14, wherein each of the one or more non-natural amino acids is independently selected from the group consisting of para-acetyl phenylalanine, 4- acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)), 3-O-(N-acetyl-beta-D-glucosaminyl)- acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2-aminooctanoic WSGR Ref. No: 31362-826.601 acid, 2-amino-L-phenylalanine, 3-amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L- tyrosine, 3-amino-L-tyrosine, 4-azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin- 5yl)-L-alanine, 3-borono-L-phenylalanine, 4-borono-L-phenylalanine, 4-bromo-L-phenylalanine, p- carboxymethyl-L-phenylalanine, 4-carboxy-L-phenylalanine, p-cyano-L-phenylalanine, 3,4- dihydroxy-L-phenylalanine (L-DOPA), 4-ethynyl-L-phenylalanine, 2-fluoro-L-phenylalanine, 3- fluoro-L-phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl-beta-D- galactosaminyl)-L-serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L- phenylalanine, 4-isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O- mannopyranosyl-L-serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L- phenylalanine, 3-methyl-L-phenylalanine, O-methyl-L-tyrosine, 3-(2-naphthyl)-L-alanine, 5-nitro- L-histidine, 4-nitro-L-histidine, 4-nitro-L-leucine, 2-nitro-L-phenylalanine, 3-nitro-L-phenylalanine, 4-nitro-L-phenylalanine, 4-nitro-L-tryptophan, 5-nitro-L-tryptophan, 6-nitro-L-tryptophan, 7-nitro- L-tryptophan, 2-nitro-L-tyrosine, 3-nitro-L-tyrosine, O-phospho-L-serine, O-phospho-L-tyrosine, 4- propargyloxy-L-phenylalanine, O-2-propyn-1-yl-L-tyrosine, 4-sulfo-L-phenylalanine and O-sulfo- L-tyrosine. B16. The ADC of any one of embodiments B1 to B15, wherein at least one of the non-naturally occurring amino acids is para-acetyl phenylalanine; optionally, wherein at least one of the non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L-phenylalanine (pAF)). B17. The ADC of any one of embodiments B1 to B16, wherein each of the one or more non-natural amino acids is the same. B18. The ADC of embodiment B17, wherein each of the one or more non-natural amino acids is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L- phenylalanine (para-acetyl-L-phenylalanine (pAF)). B19. The ADC of any one of embodiments B1 to B18, wherein the antibody, antibody fragment or variant thereof comprises 1, 2, 3 or 4 non-natural amino acids. B20. The ADC of any one of embodiments B1 to B19, wherein d is 1, 2, 3 or 4. B21. The ADC of embodiment B20, wherein d is 2, 3 or 4; optionally, d is 4. B22. The ADC of any one of embodiments B1 to B21, wherein Ab comprises two heavy chains and two light chains, each said heavy chain having a heavy chain sequence and each said light chain having a light chain sequence, wherein each said heavy chain sequence and each said light chain sequence comprises one non-natural amino acid; and d is 4. B23. The ADC of any one of embodiments B1 to B22, wherein L consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and WSGR Ref. No: 31362-826.601 at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid; , wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl. B24. The ADC of any one of embodiments B1 to B22, wherein the linker L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–U–alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, WSGR Ref. No: 31362-826.601 –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–; wherein: each U is -NH-AA-C(O)-, wherein each AA is independently an amino acid; optionally, each U is independently: ;
Figure imgf000205_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, WSGR Ref. No: 31362-826.601 –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; optionally, each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and each *, when present, denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI). B25. The ADC of any one of embodiments B1 to B24, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn– and *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: each J is independently:
Figure imgf000206_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and WSGR Ref. No: 31362-826.601 each * denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI). B26. The ADC of embodiment B25, wherein L is selected from the group consisting of:
Figure imgf000207_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O- of Formula (VI); and each + denotes connection to E. B27. The ADC of embodiment B26, wherein each m is independently 1, 2 or 3; each n is independently 1, 2 or 3; each q is independently 1, 2 or 3; each i is 0 or 1; each * denotes the connection of L to (a) -N(H) of Formula (V), or (b) -O of Formula (VI); and WSGR Ref. No: 31362-826.601 each + denotes connection to E. B28. The ADC of any one of embodiment B3 to B25, wherein: each alkylene, when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each m, when present, is independently 1, 2 or 3; each n is independently 1, 2 or 3; and each q, when present, is independently 1, 2 or 3. B29. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-trophoblast antigen 2 (anti-TROP2) antibody. B30. The ADC of embodiment B29, wherein the anti-TROP2 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17 (Table 1). B31. The ADC of embodiment B30, wherein the anti-TROP2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 5, and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, and 17. B32. The ADC of embodiment B31, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1 and 2, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. B33. The ADC of embodiment B31, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 5 and 6, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. B34. The ADC of embodiment B31, B32 or B33, wherein the heavy chain sequence comprises at least one non-natural amino acid. B35. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-CD70 antibody. B36. The ADC of embodiment B35, wherein the anti-CD70 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 18, 19, 20, 21, 22, 23 and 24 (Table 2). B37. The ADC of embodiment B36, wherein the anti-CD70 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 18 and 20, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. WSGR Ref. No: 31362-826.601 B38. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-HER2 antibody. B39. The ADC of embodiment B38, wherein the anti-HER2 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 25, 26, 27 and 28 (Table 3). B40. The ADC of embodiment B39, wherein the anti-HER2 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 25 and 26, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 27 and 28. B41. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-PSMA antibody. B42. The ADC of embodiment B41, wherein the anti-PSMA antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 and 45 (Table 4). B43. The ADC of embodiment B42, wherein the anti-PSMA antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 29, 34, 36, 38, 40, 42 and 44 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45. B44. The ADC of embodiment B43, wherein the heavy chain sequence comprises an amino acid of SEQ ID No: 36, and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, 35, 37, 39, 41, 43 and 45. B45. The ADC of embodiment B44, wherein the heavy chain sequence comprises an amino acid of SEQ ID No: 36, and wherein the light chain sequence comprises an amino acid sequence of SEQ ID NO: 37. B46. The ADC of any one of embodiments B1 to B28, wherein Ab is an anti-HER3 antibody. B47. The ADC of embodiment B46, wherein the anti-HER3 antibody comprises a sequence selected from the group consisting of SEQ ID NOs: 46 to 58 (Table 5). B48. The ADC of embodiment B47, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 46 or 58 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57. B49. The ADC of embodiment B47, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid WSGR Ref. No: 31362-826.601 sequence of SEQ ID NO: 58 and wherein the light chain sequence comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 and 57. B50. The ADC of any one of embodiments B46 to B49, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and the light chain sequence comprises an amino acid sequence of SEQ ID NO: 50. B51. The ADC of embodiment B50, wherein the anti-HER3 antibody comprises two heavy chain sequences and two light chain sequences, wherein each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 50. B52. The ADC of embodiment B50 or B51, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 50. B53. The ADC of any one of embodiments B46 to B49, wherein the anti-HER3 antibody comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and the light chain sequence comprises an amino acid sequence of SEQ ID NO: 51. B54. The ADC of embodiment B53, wherein the anti-HER3 antibody comprises two heavy chain sequences and two light chain sequences, wherein each heavy chain sequence comprises an amino acid sequence of SEQ ID NO: 58 and each light chain sequence comprises an amino acid sequence of SEQ ID NO: 51. B55. The ADC of embodiment B53 or B54, wherein each heavy chain sequence has an amino acid of SEQ ID NO: 58 and each light chain sequence has an amino acid sequence of SEQ ID NO: 51. B56. The ADC of any one of embodiments B1 to B55, wherein the ADC is an ADC of Formula (V):
Figure imgf000210_0001
. B57. The ADC of any one of embodiments B1 to B56, wherein the ADC is an ADC of Formula (Va): WSGR Ref. No: 31362-826.601
Figure imgf000211_0001
; wherein n is an integer from 1 to 10. B58. The ADC of embodiment B57, wherein n is 1, 2 or 3; optionally, wherein n is 2. B59. The ADC of embodiment B57 or B58, wherein E is: ; wherein + denotes connection to (CH2)n; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl; optionally, wherein Rc is methyl. B60. The ADC of any one of embodiments B1 to B56, wherein the ADC is an ADC of Formula (Vb):
Figure imgf000211_0002
; wherein m is an integer from 1 to 10, and n is an integer from 1 to 10. B61. The ADC of embodiment B60, wherein m is 1, 2 or 3, and n is 1, 2 or 3. B62. The ADC of embodiment B60 or B61, wherein E is:
Figure imgf000211_0003
; wherein + denotes connection to (CH2CH2O)m; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl; optionally, wherein, Rc is methyl. B63. The ADC of any one of embodiments B1 to B55, wherein the ADC is an ADC of Formula (VI): WSGR Ref. No: 31362-826.601
Figure imgf000212_0001
. B64. The ADC of any one of embodiments B1 to B55 or B63, wherein the ADC is an ADC of
Figure imgf000212_0002
wherein n is an integer from 1 to 10. B65. The ADC of embodiment B64, wherein n is 1, 2 or 3; optionally, wherein n is 2. B66. The ADC of embodiment B63, B64 or B65, wherein E is: ; wherein + denotes connection to (CH2)n; the wavy line denotes connection to Ab; and Rc is unsubstituted C1-C6 alkyl; optionally, wherein Rc is methyl. B67. A pharmaceutical composition comprising an ADC of any one of embodiments B1 to B66 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. C1. A compound of Formula (II):
Figure imgf000212_0003
wherein: Drug has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000213_0001
n is independently 1 or 2; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2; wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, wherein ** denotes connection to L1, wherein each i is independently 0, 1, 2, 3, 4, 5 or 6 and each j is independently 0, 1, 2, 3, 4, 5 or 6; and L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, q is 1, 2, 3, 4, 5 or 6 and r is 1, 2, 3, 4, 5 or 6; or L2b is selected from the group consisting of: WSGR Ref. No: 31362-826.601
Figure imgf000214_0001
; wherein [*] denotes connection to L3, and each Z1 is independently C(H) or N; L3 is H2N-O-(CH2)s-C(O)-NH , H2N-O-(CH2)s-C(O) , H2N-O-(CH2)s , H2N-O-(CH2)s-O , H2N-O-(CH2CH2O)s-CH2CH2C(O) , maleimidyl-(CH2)s-C(O) , maleimidyl-(CH2)s , maleimidyl- (CH2CH2O)sCH2CH2C(O) , Br-CH2-(CO) , Y1-C(O)-(CH2)sC(O) or Y1-C(O)-(CH2CH2O)s- CH2CH2C(O) , wherein s is 1, 2, 3, 4, 5 or 6 and Y1 is OH or a leaving group; and each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- CH2 [**], (CH2)v-C(O) [**], O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**], O-CH2- O-C(O) [**], NH-(CH2)v [**], (CH2)v(OCH2CH2)w [**], (OCH2CH2)w-(CH2)v [**], (CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof. C2. The compound of embodiment C1, wherein n is 1. C3. The compound of embodiment C1 or C2, wherein X and Y are O. C4. The compound of embodiment C1, C2 or C3, wherein L1 and L2 are absent. C5. The compound of any one of embodiments C1 to C4, wherein L3 is H2N-O-(CH2)s , wherein s is 1, 2, 3, 4, 5 or 6. C6. The compound of embodiment C5, wherein s is 1, 2 or 3. C7. The compound of any one of embodiments C1 to C6, wherein Linker is O-(CH2)v [**] or O- (CH2)v-O-C(O) [**], wherein v is 1, 2, 3, 4, 5 or 6. C8. The compound of any one of embodiments C1 to C7, wherein: Drug is:
Figure imgf000214_0002
WSGR Ref. No: 31362-826.601 Linker is O-(CH2)v-O-C(O) [**], wherein v is 1, 2, 3, 4, 5 or 6. C9. The compound of any one of embodiments C1 to C8 having the following structure:
Figure imgf000215_0001
or a pharmaceutically acceptable salt thereof. C10. The compound of any one of embodiments C1 to C7, wherein: Drug is:
Figure imgf000215_0002
Linker is O-(CH2)v [**], wherein v is 1, 2, 3, 4, 5 or 6. C11. The compound of any one of embodiments C1 to C7 and C10 having the following structure:
Figure imgf000215_0003
or a pharmaceutically acceptable salt thereof. C12. A pharmaceutical composition comprising a compound of any one of embodiments C1 to C11 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient.
Figure imgf000215_0004
(III); WSGR Ref. No: 31362-826.601 wherein: Drug has the following structure:
Figure imgf000216_0001
n is independently 1 or 2; Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, , wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6 and each j is independently 0, 1, 2, 3, 4, 5 or 6; and L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, q is 1, 2, 3, 4, 5 or 6 and r is 1, 2, 3, 4, 5 or 6; L3 is H2N-O-(CH2)s-C(O) , H2N-O-(CH2)s , H2N-O-(CH2CH2O)s-CH2CH2C(O) , maleimidyl-(CH2)s-C(O) , maleimidyl-(CH2)s , maleimidyl-(CH2CH2O)sCH2CH2C(O) , Br-CH2- WSGR Ref. No: 31362-826.601 C(O) , Y1-C(O)-(CH2)sC(O) , or Y1-C(O)-(CH2CH2O)s-CH2CH2C(O) , wherein s is 1, 2, 3, 4, 5 or 6 and Y1 is OH or a leaving group; and each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- CH2 [**], (CH2)v-C(O) [**], O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**], O-CH2- O-C(O) [**], NH-(CH2)v [**], (CH2)v(OCH2CH2)w [**], (OCH2CH2)w-(CH2)v [**], (CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof. D2. The compound of embodiment D1, wherein Drug has the following structure:
Figure imgf000217_0001
. D3. The compound of embodiment D1, wherein Drug has the following structure:
Figure imgf000217_0002
. D4. A pharmaceutical composition comprising a compound of any one of embodiments D1 to D3 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. E1. A compound of Formula (IV):
Figure imgf000217_0003
wherein: Drug has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000218_0001
n is 1, 2 or 3; each p is independently 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or p is an integer greater than 10; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , unsubstituted C1-C6 alkylene, C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, C3-C6 cyclic alkylene or * (OCH2CH2)m , wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6, and each k is independently 0, 1, 2, 3, 4, 5 or 6; L2 is absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, or L2 is L2c(L2a )3 when n is 3, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy, wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5, or 6, and each j is independently 0, 1, 2, 3, 4, 5, or 6, L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, q is 1, 2, 3, 4, 5 or 6, and r is 1, 2, 3, 4, 5 or 6; and L2c is a tetravalent moiety selected from the group consisting of C, Si, P, P(=O) and N+; WSGR Ref. No: 31362-826.601 L3 is H2N-O-(CH2)s-C(O) , H2N-O-(CH2)s , H2N-O-(CH2CH2O)s-CH2CH2C(O) , maleimidyl-(CH2)s-C(O) , maleimidyl-(CH2)s , maleimidyl-(CH2CH2O)sCH2CH2C(O) , Br-CH2-
Figure imgf000219_0001
wherein s is 1, 2, 3, 4, 5 or 6 and Y1 is OH or a leaving group; and each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O-
Figure imgf000219_0002
alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; or a pharmaceutically acceptable salt thereof. E2. The compound of embodiment E1, wherein Drug has the following structure:
Figure imgf000219_0003
. E3. The compound of embodiment E1, wherein Drug has the following structure:
Figure imgf000219_0004
. E4. A pharmaceutical composition comprising a compound of any one of embodiments E1 to E3 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. F1. A compound of Formula (VII) or (VIII): WSGR Ref. No: 31362-826.601 ;
Figure imgf000220_0001
L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety; optionally, W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, -C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein Rb is H or unsubstituted alkyl, Rc is unsubstituted alkyl, and Rd is H, unsubstituted alkyl or a carboxylic acid protecting group; or a pharmaceutically acceptable salt thereof. F2. The compound of embodiment F1, wherein the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. F3. The compound of embodiment F1 or F2, wherein L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, arylene is phenylene. F4. The compound of embodiment F3, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and - N(Rw)-, wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof. F5. The compound of embodiment F3 or F4, wherein each Rw is independently H or methyl. F6. The compound of any one of embodiments F1 to F5, wherein W is selected from the group consisting of: WSGR Ref. No: 31362-826.601
Figure imgf000221_0001
-N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, an activated ester, –O–NH2 and an optionally substituted monocyclic or polycyclic group comprising a cyclooctyne; wherein: Rb is H or unsubstituted C1-C6 alkyl, Rc is unsubstituted C1-C6 alkyl, Rd is H, unsubstituted C1-C6 alkyl or a carboxylic acid protecting group, Rf is H or unsubstituted C1-C6 alkyl, s is 0, 1, 2, 3, 4, 5 or 6, and t is 0, 1, 2, 3, 4, 5 or 6. F7. The compound of embodiment F6, wherein the optionally substituted monocyclic or polycyclic group comprising the cyclooctyne is selected from the group consisting of:
Figure imgf000221_0002
, . F8. The compound of any one of embodiments F1 to F6, wherein W is -ONH2. F9. The compound of any one of embodiments F1 to F8, wherein L consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and optionally, at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, - C(O)-, -N(Rw)- and an amino acid; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl. F10. The compound of any one of embodiments F1 to F9, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, WSGR Ref. No: 31362-826.601 *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–U–alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–,c –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, WSGR Ref. No: 31362-826.601 –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–; wherein: each U is -NH-AA-C(O)-, wherein each AA is independently an amino acid; each J is independently:
Figure imgf000223_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and *, when present, denotes the connection to (a) -N(H) of Formula (VII), or (b) -O of Formula (VIII). F11. The compound of embodiment F10, wherein each U is independently:
Figure imgf000223_0002
. F12. The compound of any one of embodiments F1 to F9, wherein L consists of: a phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)- and - WSGR Ref. No: 31362-826.601 N(Rw)-; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; and combinations thereof; optionally, each Rw is independently H or methyl. F13. The compound of any one of embodiments F1 to F9 and F12, wherein L is elected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, WSGR Ref. No: 31362-826.601 *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn– alkylene–; wherein: each J is independently:
Figure imgf000225_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and * denotes the connection to (a) -N(H) of Formula (VII), or (b) -O of Formula (VIII). F14. The compound of embodiments F1 to F9 and F12 to F13, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, WSGR Ref. No: 31362-826.601 *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn– and *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: each J is independently:
Figure imgf000226_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and * denotes the connection to (a) -N(H) of Formula (VII), or (b) -O of Formula (VIII). F15. The compound of any one of embodiments F3 to F14, wherein: each alkylene, when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; and each n is independently 1, 2 or 3. F16. The compound of embodiment F14, wherein L is *–C(O)-O-alkylene-O-P(=O)(OH)-O- P(=O)(OH)-(O-alkylene)nn–. F17. The compound of embodiment F14 or F15, wherein L is *–C(O)-O-alkylene-O-P(=O)(OH)- O-P(=O)(OH)-(O-alkylene)nn–. F18. The compound of embodiment F14, or F15 wherein L is *–alkylene-O-P(=O)(OH)-O- P(=O)(OH)-(O)i-alkylene–. F19. The compound of embodiment F14, wherein L is selected from the group consisting of:
Figure imgf000226_0002
WSGR Ref. No: 31362-826.601
Figure imgf000227_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection to (a) -N(H) of Formula (VII), or (b) -O of Formula (VIII); and each + denotes connection to W. F20. The compound of embodiment F19, wherein each m is independently 1, 2 or 3; each n is independently 1, 2 or 3; each q is independently 1, 2 or 3; each i is 0 or 1; each * denotes the connection to (a) -N(H) of Formula (VII), or (b) -O of Formula (VIII); and each + denotes connection to W. F21. The compound of any one of F9 to F20, wherein i is 1. F22. The compound of any one of embodiments F1 to F21, wherein the compound is a compound of Formula (VII): WSGR Ref. No: 31362-826.601
Figure imgf000228_0001
; or a pharmaceutically acceptable salt thereof. F23. The compound of embodiment F22 having the following structure:
Figure imgf000228_0002
or a pharmaceutically acceptable salt thereof. F24.The compound of any one of embodiments F1 to F21, wherein the compound is a compound of Formula (VIII):
Figure imgf000228_0003
; or a pharmaceutically acceptable salt thereof. F25. The compound of embodiment F24 having the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000229_0001
or a pharmaceutically acceptable salt thereof. F26. A pharmaceutical composition comprising a compound of any one of embodiments F1 to F25 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. G1. An ADC of any one of embodiments A1 to A18 or B1 to B28 and B56 to B66, wherein Ab is an anti-trophoblast antigen 2 antibody, antibody fragment or variant thereof. G2. The ADC of embodiment G1, wherein the anti-TROP2 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 1. G3. The ADC of embodiment G2, wherein the anti-TROP2 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 1, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 1. G4. The ADC of embodiment G3, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114. G5. The ADC of embodiment G4, wherein the heavy chain comprises one non-natural amino acid. G6. The ADC of embodiment G3, G4 or G5, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each at least one non- natural amino acid in the light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G7. The ADC of any one of embodiments G1 to G6, wherein the anti-TROP2 antibody, antibody fragment or variant thereof comprises two heavy chain sequences, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each heavy chain sequence is Kabat position 114. WSGR Ref. No: 31362-826.601 G8. The ADC of embodiment G7, wherein each heavy chain sequence comprises one non-natural amino acid. G9. The ADC of embodiment G7 or G8, wherein the anti-TROP2 antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each of the one or more non-natural amino acid in each light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position occupied by each at least one non-natural amino acid in each light chain sequence is position 121. G10. The ADC of any one of embodiment G1 to G9, wherein the anti-TROP2 antibody, antibody fragment or variant thereof comprises two heavy chain sequences and two light chain sequences, wherein: each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 157, 168, 172, 202 and 205; optionally, the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)). G11. The ADC of any one of embodiments A1 to A18 or B1 to B28 and B56 to B66, wherein Ab is an anti-CD70 antibody, antibody fragment or variant thereof. G12. The ADC of embodiment G11, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 2. G13. The ADC of embodiment G12, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 2, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 2. G14. The ADC of embodiment G13, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114. G15. The ADC of embodiment G14, wherein the heavy chain comprises one non-natural amino acid. WSGR Ref. No: 31362-826.601 G16. The ADC of embodiment G13, G14 or G15, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each at least one non- natural amino acid in the light chain sequence is independently selected from the group consisting of position 110, 112, 114 and 121; optionally, the position occupied by one of the one or more non- natural amino acid in the light chain sequence is position 121. G17. The ADC of any one of embodiment G1 to G16, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises two heavy chain sequences, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each heavy chain sequence is Kabat position 114. G18. The ADC of embodiment G17, wherein the heavy chain comprises one non-natural amino acid. G19. The ADC of embodiment G17 or G18, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each at least one non-natural amino acid in each light chain sequence is independently selected from the group consisting of position 110, 112, 114 and 121; optionally, the position occupied by one of the one or more non-natural amino acid in each light chain sequence is position 121. G20. The ADC of any one of embodiment G1 to G19, wherein the anti-CD70 antibody, antibody fragment or variant thereof comprises two heavy chain sequences and two light chain sequences, wherein: each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 157, 168, 172, 202 and 205; optionally, the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)). G21. The ADC of any one of embodiments A1 to A18 or B1 to B28 and B56 to B66, wherein Ab is an anti-HER2 antibody, antibody fragment or variant thereof. G22. The ADC of embodiment G21, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 3. WSGR Ref. No: 31362-826.601 G23. The ADC of embodiment G22, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 3, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 3. G24. The ADC of embodiment G23, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114. G25. The ADC of embodiment G24, wherein the heavy chain comprises one non-natural amino acid. G26. The ADC of embodiment G23, G24 or G25, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G27. The ADC of any one of embodiments G21 to G26, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises two heavy chain sequences, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each heavy chain sequence is Kabat position 114. G28. The ADC of embodiment G27, wherein the heavy chain comprises one non-natural amino acid. G29. The ADC of embodiment G27 or G28, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each light chain sequence is position 110121. G30. The ADC of any one of embodiment G21 to G29, wherein the anti-HER2 antibody, antibody fragment or variant thereof comprises two heavy chain sequences and two light chain sequences, wherein: each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is position 121; optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)). G31. The ADC of any one of embodiments A1 to A18, B1 to B28 and B56 to B66, wherein Ab is an anti-PSMA antibody, antibody fragment or variant thereof. WSGR Ref. No: 31362-826.601 G32. The ADC of embodiment G31, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 4. G33. The ADC of embodiment G32, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 4, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 4. G34. The ADC of embodiment G33, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114. G35. The ADC of embodiment G34, wherein the heavy chain comprises one non-natural amino acid. G36. The ADC of embodiment G33, G34 or G35, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G37. The ADC of any one of embodiments G31 to G36, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises two heavy chain sequences, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each heavy chain sequence is Kabat position 114. G38. The ADC of embodiment G37, wherein the heavy chain comprises one non-natural amino acid. G39. The ADC of embodiment G37 or G38, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each light chain sequence is position 110, 121. G40. The ADC of any one of embodiments G31 to G39, wherein the anti-PSMA antibody, antibody fragment or variant thereof comprises two heavy chain sequences and two light chain sequences, wherein: each heavy chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is Kabat position 114; and each light chain sequence contains one non-natural amino acid, and the position occupied by each non-natural amino acid is position 121; or each light chain does not contain a non-natural amino acid (each light chain amino acid sequence consists of naturally-occurring amino acids, or more particularly, natural amino acids selected from the group consisting of the twenty canonical amino acids; WSGR Ref. No: 31362-826.601 optionally, wherein each non-natural amino acid is para-acetyl phenylalanine; optionally, wherein each non-natural amino acid is 4-acetyl-L-phenylalanine (para-acetyl-L- phenylalanine (pAF)). G41. The ADC of any one of embodiments A1 to A18, B1 to B28 and B56 to B66, wherein Ab is an anti-HER3 antibody, antibody fragment or variant thereof. G42. The ADC of embodiment G41, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises at least one sequence listed in Table 5. G43. The ADC of embodiment G42, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises a heavy chain sequence and a light chain sequence, wherein the heavy chain sequence comprises an amino acid sequence selected from the group consisting of the heavy chain sequences listed in Table 5, and the light chain sequence comprises an amino acid sequence selected from the group consisting of the light chain sequences listed in Table 5. G44. The ADC of embodiment G43, wherein the heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in the heavy chain sequence is Kabat position 114. G45. The ADC of embodiment G44, wherein the heavy chain comprises one non-natural amino acid. G46. The ADC of embodiment G43, G44 or G45, wherein the light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each of the one or more non-natural amino acid in the light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position occupied by one of the one or more non-natural amino acid in the light chain sequence is position 121. G47. The ADC of any one of embodiments G41 to G46, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises two heavy chain sequences, wherein each heavy chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by one of the one or more non-natural amino acid in each heavy chain sequence Kabat position 114. G48. The ADC of embodiment G47, wherein the heavy chain comprises one non-natural amino acid. G49. The ADC of embodiment G47 or G48, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises two light chain sequences, wherein each light chain sequence comprises at least one of the one or more non-natural amino acids, and the position occupied by each at least one non-natural amino acid in each light chain sequence is independently selected from the group consisting of position 110, 112, 114, 121, 127, 149, 156, 168, 202 and 205; optionally, the position WSGR Ref. No: 31362-826.601 occupied by one of the one or more non-natural amino acid in each light chain sequence is position 121. G50. The ADC of any one of embodiments G47 to G49, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises two heavy chain sequences of SEQ ID NO: 58 and two light chain sequences of SEQ ID NO: 50. G51. The ADC of any one of embodiments G47 to G49, wherein the anti-HER3 antibody, antibody fragment or variant thereof comprises two heavy chain sequences of SEQ ID NO: 58 and two light chain sequences of SEQ ID NO: 51. G52. A pharmaceutical composition comprising an ADC of any one of embodiments G1 to G51 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. H1. A linker having the following structure: –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: i is 0 or 1; and each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; H2. The linker of embodiment H1, wherein i is 1. H3. The linker of embodiment H1 or H2, wherein the linker has the following structure: –C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-O-(CH2CH2)–. I1. A drug-linker compound having the following structure: Drug–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–**; wherein: i is 0 or 1; each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; ** denotes a connection to a reactive moiety; and and Drug is any drug; optionally Drug is a cytotoxic agent. I2. The drug-linker compound of embodiment I1, wherein i is 1. I3. The drug-linker compound of embodiment I2, wherein the linker carbonyl group (C(O)) is joined to Drug via a covalent bond to an -N(Rw) group of the Drug, wherein Rw is H, C1-C6 alkyl, aryl or heteroaryl. WSGR Ref. No: 31362-826.601 I4. The drug-linker compound of I1, I2 or I3, wherein the drug is exatecan, or a salt thereof, and the linker carbonyl group (C(O)) is joined to the -N(H) group of the exatecan, or the salt thereof. I5. The drug-linker compound of any one of embodiments I1 to I4, wherein the compound has the following structure: Drug–C(O)-O-(CH2)-O-P(=O)(OH)-O-P(=O)(OH)-O-(CH2CH2)–**. I6. The drug-linker compound of any one of embodiments I1 to I5, wherein the reactive moiety comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, -C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein Rb is H or unsubstituted alkyl, Rc is unsubstituted alkyl, and Rd is H, unsubstituted alkyl or a carboxylic acid protecting group. I7. The drug-linker compound of any one of embodiments I1 to I6, wherein the reactive moiety is selected from the group consisting of:
Figure imgf000236_0001
-N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, an activated ester, –O–NH2 and an optionally substituted monocyclic or polycyclic group comprising a cyclooctyne; wherein: Rb is H or unsubstituted C1-C6 alkyl, Rc is unsubstituted C1-C6 alkyl, Rd is H, unsubstituted C1-C6 alkyl or a carboxylic acid protecting group, Rf is H or unsubstituted C1-C6 alkyl, s is 0, 1, 2, 3, 4, 5 or 6, and t is 0, 1, 2, 3, 4, 5 or 6. I8. The drug-linker compound of any one of embodiments I1 to I7, wherein the reactive moiety is - O-NH2. I9. A pharmaceutical composition comprising a drug-linker compound of any one of embodiments I1 to I8 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. J1. An ADC composition, comprising or consisting essentially of: (a) an ADC of any one of embodiments A1 to A45, wherein p is 1; (b) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 2; WSGR Ref. No: 31362-826.601 (c) an ADC any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 3; (d) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 4; (e) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 5; (f) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 6; (g) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 7; or (h) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 8; or a combination of any two or more of the foregoing; wherein the ADC composition is characterized as having a DAR of at least about 1 and at most about 8. J2. The ADC composition of embodiment J1, wherein the ADC composition is characterized as having a DAR of at least about 2 and at most about 8, at least about 2 and at most about 6, at least about 2 and at most about 4, or at least about 3 and at most about 4. J3. An ADC composition of embodiment J1, consisting essentially of: (a) an ADC of any one of embodiments A1 to A45, wherein p is 1; (b) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 2; (c) an ADC of any one of embodiments A1 to A45), wherein the ADC is identical to (a), except that p is 3; (d) an ADC of any one of embodiments A1 to A45, wherein the ADC is identical to (a), except that p is 4; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. J4. The ADC composition of embodiment J3, wherein the ADC composition is characterized as having a DAR of at least about 2 and at most about 4, or at least about 3 and at most about 4. J5. The ADC of any one of embodiments J1 to J4, wherein the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. J6. A pharmaceutical composition comprising an ADC of any one of embodiments J1 to J5 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. K1. An ADC composition comprising or consisting essentially of: WSGR Ref. No: 31362-826.601 (a) an ADC of any one of embodiments B1 to B66, wherein d is 1; (b) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 2; (c) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 3; (d) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 4; (e) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 5; (f) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 6; (g) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 7; (h) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 8; (i) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 9; or (j) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 10; or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 10. K2. The ADC composition of embodiment K1, wherein the ADC composition is characterized as having a DAR of at least about 1 and at most about 8, at least about 2 and at most about 8, at least about 2 and at most about 6, at least about 2 and at most about 4, or at least about 3 and at most about 4. K3. The ADC composition of embodiment K1 or K2, consisting essentially of: (a) an ADC of any one of embodiments B1 to B66, wherein d is 1; (b) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 2; (c) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 3; or (d) an ADC of any one of embodiments B1 to B66, wherein the ADC is identical to (a), except that d is 4; WSGR Ref. No: 31362-826.601 or a combination of any two or more of the foregoing; wherein the composition is characterized as having a DAR of at least about 1 and at most about 4. K4. The ADC composition of embodiment K3, wherein the ADC composition is characterized as having a DAR of at least about 2 and at most about 4, or at least about 3 and at most about 4. K5. The ADC composition of any one of embodiments K1 to K4, wherein each ADC is a compound of Formula (V). K6. The ADC of embodiment K5, wherein each ADC is a compound of Formula (Va). K7. The ADC of embodiment K5, wherein each ADC is a compound of Formula (Vb). K8. The ADC of embodiment K5, wherein each ADC is a compound of Formula (VI). K9. The ADC of any one of embodiments K1 to K8, wherein the ADC composition is characterized as having a DAR of at least about 3 and at most about 4. K10. A pharmaceutical composition comprising an ADC of any one of embodiments K1 to K9 and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only and are not intended to limit the scope of the disclosure. Indeed, the novel compositions, methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the compositions, systems and methods described herein may be made without departing from the spirit of the disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure. Accordingly, the scope of the present inventions is defined only by reference to the appended claims. Features, materials, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example are to be understood to be applicable to any other aspect, embodiment or example described in this section or elsewhere in this specification unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the compositions, steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The protection is not restricted to the details of any foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the compositions, steps of any method or process so disclosed. Furthermore, certain features that are described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, WSGR Ref. No: 31362-826.601 various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as a subcombination or variation of a subcombination. The features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. Also, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described components and systems can generally be integrated together in a single product or packaged into multiple products. For purposes of this disclosure, certain aspects, advantages, and novel features are described herein. Not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the disclosure may be embodied or carried out in a manner that achieves one advantage or a group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural reference unless the context clearly indicates otherwise. Conditional language, such as "can," "could," "might," or "may," unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, and/or steps are included or are to be performed in any particular embodiment. Conjunctive language such as the phrase "at least one of X, Y, and Z," unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z. Language of degree used herein, such as the terms ''approximately," "about," "generally," “substantial” and "substantially" as used herein represent a value, amount, quantity or characteristic close to the stated value, amount, quantity or characteristic that still performs a desired function or WSGR Ref. No: 31362-826.601 achieves a desired result. For example, the terms "approximately", "about", "generally," “substantial” and "substantially'' may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of: within less than 0.1% of, and within less than 0.01% of the stated amount. As used herein and in the appended claims, the term “comprising” is open ended, and the broadest reasonable interpretation of the term applies. The present disclosure contemplates alternative embodiments wherein the term “consisting of” can be used in place of each recitation of the term “comprising” herein. The scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments in this section or elsewhere in this specification and may be defined by claims as presented in this section or elsewhere in this specification or as presented in the future. The language of the claims is to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive.

Claims

WSGR Ref. No: 31362-826.601 WHAT IS CLAIMED: 1. An antibody-drug conjugate (ADC) of Formula (I):
Figure imgf000242_0001
each n is independently 1 or 2; p is 1, 2, 3, 4, 5, 6, 7 or 8; each Y is independently O, N(Rw) or CH2; wherein each Rw is independently H or unsubstituted alkyl; each X is independently O or S; each L1 is independently absent, * (CH2)m , * CH2-O-(CH2)m , * (CH2)m-O-CH2 , * C(O)-(CH2)m , * NH-(CH2)m , * (CH2)m(OCH2CH2)k , * NH-(CH2)m(OCH2CH2)k , C3-C6 cyclic alkylene, * (OCH2CH2)m , unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1- C3 alkoxy; wherein * denotes connection to L2, each m is independently 0, 1, 2, 3, 4, 5 or 6 and each k is independently 0, 1, 2, 3, 4, 5 or 6; each L2 is independently absent or L2a when n is 1, or L2 is L2b(L2a )2 when n is 2, wherein: each L2a is independently absent, (CH2)iC(O) **, (CH2)i(OCH2CH2)jC(O) **, (CH2)i(OCH2)jC(O) **, NH-(CH2)iC(O) **, NH-(CH2)i(OCH2CH2)jC(O) **, NH- (CH2)i(OCH2)jC(O) **, C3-C6 cyclic alkylene, unsubstituted C1-C6 alkylene, or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein ** denotes connection to L1, each i is independently 0, 1, 2, 3, 4, 5 or 6 and each j is independently 0, 1, 2, 3, 4, 5 or 6; and WSGR Ref. No: 31362-826.601 each L2b is a trivalent moiety selected from the group consisting of [*] NHCH((CH2)qO )((CH2)rO ), [*] NHCH((CH2)q )((CH2)rO ), [*] NHCH((CH2)q )((CH2)r ), [*] NHCH((CH2)qC(O) )((CH2)rO ), [*] NHCH((CH2)qC(O) )((CH2)r ), [*] NHCH((CH2)q(C(O) )((CH2)rC(O) ), [*] NHCH(C(O) )((CH2)rO ) and [*] NHCH(C(O) )((CH2)rC(O) ), wherein [*] denotes connection to L3, each q is independently 1, 2, 3, 4, 5 or 6, and each r is independently 1, 2, 3, 4, 5 or 6; or L2b is selected from the group consisting of:
Figure imgf000243_0001
, wherein [*] denotes connection to L3, and each Z1 is independently C(H) or N; each L3 is independently [**]=N-O-(CH2)s-C(O)-NH , [**]=N-O-(CH2)s-C(O) , [**]=N-O- (CH2)s , [**]=N-O-(CH2)s-O , [**]=N-O-(CH2CH2O)s-CH2CH2C(O) , [**] S-succinimidyl- (CH2)s-C(=O) , [**] S-succinimidyl-(CH2)s , [**] S-succinimidyl-(CH2CH2O)sCH2CH2C(O) , [**] S-CH2-(CO) , [**] NH-C(=O)-(CH2)sC(O) , or [**] NH-C(O)-(CH2CH2O)s-CH2CH2C(O) , wherein [**] denotes connection to Ab and each s is independently 1, 2, 3, 4, 5 or 6; or each L3 independently comprises a 6-maleimidocaproyl, a maleimidomethyl cyclohexane-1- carboxylate, a maleimidopropanoyl, a p-aminobenzyloxycarbonyl, a N-succinimidyl 4-(2- pyridylthio) pentanoate, a N-succinimidyl 4-(N-maleimidomethyl)cyclohexane-1 carboxylate or a N- succinimidyl (4-iodo-acetyl)aminobenzoate; each Linker is independently absent, (CH2)v [**], CH2-O-(CH2)v [**], (CH2)v-O- CH2 [**], (CH2)v-C(O) [**], O-(CH2)v [**], O-CH2 [**], O-(CH2)v-O-C(O) [**], O-CH2- O-C(O) [**], NH-(CH2)v [**], (CH2)v(OCH2CH2)w [**], (OCH2CH2)w-(CH2)v [**], (CH2)v(OCH2CH2)w-NH [**], C3-C6 cyclic alkylene, (OCH2CH2)v [**], unsubstituted C1-C6 alkylene or C1-C6 alkylene substituted with 1-3 groups independently selected from the group consisting of C1-C3 alkyl, hydroxy, NH2 and C1-C3 alkoxy; wherein [**] denotes connection to - N(H) or -O- of the Drug, each v is independently 0, 1, 2, 3, 4, 5 or 6 and each w is independently 0, 1, 2, 3, 4, 5 or 6; and Ab is an antibody, antibody fragment or variant thereof. 2. The ADC of claim 1, wherein Drug has the following structure: WSGR Ref. No: 31362-826.601
Figure imgf000244_0001
wherein the wavy line denotes connection to Linker. 3. The ADC of claim 1, wherein Drug has the following structure:
Figure imgf000244_0002
wherein the wavy line denotes connection to Linker. 4. An antibody-drug conjugate (ADC) of Formula (V) or (VI):
Figure imgf000244_0003
wherein: Ab is an antibody, antibody fragment or variant thereof, wherein Ab comprises one or more non-natural amino acids; L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; E is a moiety joining Ab and L; and d is an integer from 1 to 10; or a pharmaceutically acceptable salt thereof. WSGR Ref. No: 31362-826.601 5. The ADC of claim 4, wherein the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. 6. The ADC of claim 4 or 5, wherein L further comprises at least one additional moiety, wherein each of the at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, –(alkylene–O)nn–, optionally substituted arylene, -O-, - C(O)-, -N(Rw)-, -S(O)0-2-, and an amino acid, and any combination thereof; wherein each Rw is independently H or C1-C8 alkyl, wherein each nn is independently an integer from 1 to 100; optionally, each arylene is phenylene. 7. The ADC of claim 6, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)-, and -N(Rw)-, and any combination thereof; wherein each Rw is independently H or C1-C8 alkyl; and wherein each nn is independently an integer from 1 to 100. 8. The ADC of claim 6 or 7, wherein each Rw is independently H or methyl. 9. The ADC of any one of claims 4 to 8, wherein E comprises an amide, an ester, a thioester, a pyrrolidine-2,5-dione, an oxime, a 4,5-dihydro-1,2,3-triazole or a 1,4-dihydropyridazine, wherein the 4,5-dihydro-1,2,3-triazole or 1,4-dihydropyridazine is optionally fused to an 8-membered ring. 10. The ADC of any one of claims 4 to 9, wherein E is selected from the group consisting of:
Figure imgf000245_0001
WSGR Ref. No: 31362-826.601
Figure imgf000246_0001
wherein: each Rb is independently H or unsubstituted alkyl; each Rc is unsubstituted alkyl; each Rf is independently H or unsubstituted alkyl, each s is independently 0, 1, 2, 3, 4, 5 or 6, each t is independently 0, 1, 2, 3, 4, 5 or 6; each + denotes connection to L; and each wavy line denotes connection to Ab. 11. The ADC of claim 10, wherein each Rb is independently H or unsubstituted C1-C6 alkyl, each Rc is unsubstituted C1-C6 alkyl, and each Rf is independently H or unsubstituted C1-C6 alkyl. 12. The ADC of any one of claims 4 to 11, wherein E is:
Figure imgf000246_0002
wherein Rc is unsubstituted C1-C6 alkyl. 13. The ADC of claim 12, wherein Rc is methyl. 14. The ADC of any one of claims 4 to 13, wherein: L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each of the at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid; and combinations thereof; wherein each Rw is independently H or C1-C8 alkyl; and wherein each nn is independently an integer from 1 to 100; optionally, each Rw is independently H or methyl. 15. The ADC of any one of claims 4 to 14, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i–, WSGR Ref. No: 31362-826.601 *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–U–alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, WSGR Ref. No: 31362-826.601 –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–; wherein: each U is -NH-AA-C(O)-, wherein each AA is independently an amino acid; each J is independently:
Figure imgf000248_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; optionally, each alkylene is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and each *, when present, denotes the connection of L to (a) -N(H)- of Formula (V), or (b) the -O- of Formula (VI). 16. The ADC of claim 15, wherein each U is independently:
Figure imgf000248_0002
. 17. The ADC of any one of claims 4 to 15, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, WSGR Ref. No: 31362-826.601 *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn– and *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: each J is independently:
Figure imgf000249_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and each * denotes the connection of L to (a) -N(H)- of Formula (V), or (b) -O of Formula (VI). 18. The ADC of any one of claims 4 to 14, wherein L is selected from the group consisting of:
Figure imgf000249_0002
WSGR Ref. No: 31362-826.601
Figure imgf000250_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; each * denotes the connection of L to (a) -N(H)- of Formula (V), or (b) -O- of Formula (VI); and each + denotes connection to E. 19. The ADC of any one of claims 6 to 18, wherein: each alkylene, when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; each m, when present, is independently 1, 2 or 3; each n is independently 1, 2 or 3; and each q, when present, is independently 1, 2 or 3. 20. The ADC of any one of claims 4 to 19, wherein the ADC is an ADC of Formula (V):
Figure imgf000250_0002
. 21. The ADC of any one of claims 4 to 19, wherein the ADC is an ADC of Formula (VI): WSGR Ref. No: 31362-826.601
Figure imgf000251_0001
. 22. The ADC of any one of claims 4 to 21, wherein d is 1, 2, 3 or 4. 23. The ADC of any one of claims 1 to 22, wherein Ab comprises one or more non-natural amino acids. 24. The ADC of claim 23, wherein Ab is configured to bind to an antigen. 25. The ADC of claim 23 or 24, wherein Ab is configured to bind to a tumor-associated antigen (TAA) or cancer antigen. 26. The ADC of claim 23, 24 or 25, wherein Ab binds to a tumor-associated antigen (TAA) selected from the group consisting of PSMA, CD70, CD3, HER2, HER3, TROP2, VEGFR, EGFR, c-Met (HGFR), CD33, CD19, CD22, CD25 (IL-2R alpha), CD30, CD33, CD37, CD46, CD48, CD56 (NCAM-1), CD71 (Transferrin R), CD74, CD79b, CD123 (IL-3R alpha), CD138 (syndecan-1), CD142, CD166 (ALCAM), CD203c (ENPP3), CD205 (LY75), CD221 (IGF-1R), CD262 (TRAIL R2), CD276 (B7-H3), mesothelin, EpCAM, CEACAM5, CEACAM6, DLL3, ROR1, ROR2, GPNMB, GCC, GUCY2c, NaPi2b, Flt-1, Flt-3, folate receptor alpha, Tissue Factor (TF), CA6, MUC1, MUC16 (CA-125), BCMA, SLAMF7 (CS1), TIM1, CanAg, Ckit (CD117), EphA2, Nectin4, SLTRK6, FGFR2, LYPD3 (C4.4a), Cadherin 3, 5T4 (TPBG), STEAP1, PTK7, Ephrin-A4, LIV-1 (SLC39A6 or ZIP6), SLC1A5, TENB2, ETBR, integrin v3, Cripto, AGS-5 (SLC44A4), LY6E, AXL, LAMP1, LRRC15, TNF-alpha and MN/CA IX. 27. The ADC of any one of claims 23 to 26, wherein Ab binds to an antigen selected from the group consisting of TROP2, CD70, HER2, HER3 and PSMA. 28. The ADC of any one of claims 23 to 27, wherein each of the one or more non-natural amino acids, is independently selected from the group consisting of para-acetyl phenylalanine, 4-acetyl-L- phenylalanine (para-acetyl-L-phenylalanine (pAF)), 3-O-(N-acetyl-beta-D-glucosaminyl)-L- acetylgalactosamine-O-L-serine, alpha-N-acetylgalactosamine-O-L-threonine, 2-aminooctanoic acid, 2-amino-L-phenylalanine, 3-amino-L-phenylalanine, 4-amino-L-phenylalanine, 2-amino-L- tyrosine, 3-amino-L-tyrosine, 4-azido-L-phenylalanine, 4-benzoyl-L-phenylalanine, (2,2-bipyridin- WSGR Ref. No: 31362-826.601 5yl)-L-alanine, 3-borono-L-phenylalanine, 4-borono-L-phenylalanine, 4-bromo-L-phenylalanine, p- carboxymethyl-L-phenylalanine, 4-carboxy-L-phenylalanine, p-cyano-L-phenylalanine, 3,4- dihydroxy-L-phenylalanine (L-DOPA), 4-ethynyl-L-phenylalanine, 2-fluoro-L-phenylalanine, 3- fluoro-L-phenylalanine, 4-fluoro-L-phenylalanine, O-(3-O-D-galactosyl-N-acetyl-beta-D- galactosaminyl)-L-serine, L-homoglutamine, (8-hydroxyquinolin-3-yl)-L-alanine, 4-iodo-L- phenylalanine, 4-isopropyl-L-phenylalanine, O-i-propyl-L-tyrosine, 3-isopropyl-L-tyrosine, O- mannopyranosyl-L-serine, 2-methoxy-L-phenylalanine, 3-methoxy-L-phenylalanine, 4-methoxy-L- phenylalanine, 3-methyl-L-phenylalanine, O-methyl-L-tyrosine, 3-(2-naphthyl)-L-alanine, 5-nitro- L-histidine, 4-nitro-L-histidine, 4-nitro-L-leucine, 2-nitro-L-phenylalanine, 3-nitro-L-phenylalanine, 4-nitro-L-phenylalanine, 4-nitro-L-tryptophan, 5-nitro-L-tryptophan, 6-nitro-L-tryptophan, 7-nitro- L-tryptophan, 2-nitro-L-tyrosine, 3-nitro-L-tyrosine, O-phospho-L-serine, O-phospho-L-tyrosine, 4- propargyloxy-L-phenylalanine, O-2-propyn-1-yl-L-tyrosine, 4-sulfo-L-phenylalanine and O-sulfo- L-tyrosine. 29. The ADC of any one of claims 23 to 28, wherein at least one of the one or more non-natural amino acids is para-acetyl-L-phenylalanine (pAF). 30. The ADC of claim 29, wherein each of the one or more non-natural amino acids is the same. 31. The ADC of claim 29 or 30, wherein each of the one or more non-natural amino acids is para- acetyl-L-phenylalanine (pAF). 32. The ADC of any one of claims 23 to 31, wherein drug to antibody ratio is about 1, about 2, about 3 or about 4. 33. The ADC of any one of claims 23 to 32, wherein Ab comprises a heavy chain having a heavy chain amino acid sequence, a light chain having a light chain amino acid sequence, or both. 34. The ADC of claim 33, wherein the heavy chain comprises at least one of the one or more non- natural amino acids. 35. The ADC of claim 33 or 34, wherein the light chain comprises at least one of the one or more non-natural amino acids. 36. The ADC of claim 33, 34 or 35, wherein Ab comprises two heavy chains, wherein each heavy chain comprises at least one of the one or more non-natural amino acids. 37. The ADC of any one of claims 33 to 36, wherein Ab comprises two light chains; optionally, wherein each light chain comprises at least one of the one or more non-natural amino acids. 38. The ADC of any one of claims 23 to 37, wherein the one or more non-natural amino acids is 1, 2 3 or 4 non-natural amino acids. 39 The ADC of any one of claims 33 to 38, wherein Ab comprises two heavy chains and two light chains, wherein each heavy chain comprises one non-natural amino acid. WSGR Ref. No: 31362-826.601 40. The ADC of claim 39, wherein each light chain comprises one non-natural amino acid. 41. The ADC of any one of claims 23 to 33, wherein Ab is an anti-trophoblast antigen 2 antibody (anti-TROP2 Ab), antibody fragment or variant thereof. 42. The ADC of claim 41, wherein the anti-TROP2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 1 to 17. 43. The ADC of claim 42, wherein the anti-TROP2 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain amino acid sequence is selected from the group consisting of SEQ ID NOs: 5 and 6. 44. The ADC of claim 43, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 5, wherein one non-natural amino acid occupies Kabat position 114. 45. The ADC of claim 42, 43 or 44, wherein the anti-TROP2 Ab, antibody fragment or variant thereof, comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17. 46. The ADC of claim 45, wherein the light chain has the amino acid sequence of SEQ ID NO: 11, wherein one non-natural amino acid occupies position 121. 47. The ADC of any one of claims 41 to 46, wherein the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5. 48. The ADC of claim 47, wherein the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 4. 49. The ADC of claim 47, wherein the anti-TROP2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11. 50. The ADC of any one of claims 41 to 49, wherein each non-natural amino acid is para-acetyl-L- phenylalanine (pAF), and each E comprises an oxime. 51. The ADC of any one of claims 23 to 33, wherein Ab is an anti-CD70 antibody (anti-CD70 Ab), antibody fragment or variant thereof. 52. The ADC of claim 51, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 18 to 24. 53. The ADC of claim 52, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 20, wherein one non-natural amino acid occupies Kabat position 114. WSGR Ref. No: 31362-826.601 54. The ADC of claim 52 or 53, wherein the anti-CD70 Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23 and 24. 55. The ADC of claim 54, wherein the light chain has the amino acid sequence of SEQ ID NO: 19. 56. The ADC of claim 54, wherein the light chain has the amino acid sequence of SEQ ID NO: 24, wherein one non-natural amino acid occupies position 121. 57. The ADC of any one of claims 51 to 56, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 20. 58. The ADC of claim 57, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 19. 59. The ADC of claim 57, wherein the anti-CD70 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 24. 60. The ADC of any one of claims 51 to 59, wherein each non-natural amino acid is para-acetyl-L- phenylalanine (pAF), and each E comprises an oxime. 61. The ADC of any one of claims 23 to 33, wherein Ab is an anti-HER2 antibody (anti-HER2 Ab), antibody fragment or variant thereof. 62. The ADC of claim 61, wherein the anti-HER2 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 25 to 28. 63. The ADC of claim 62, wherein the anti-HER2 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 26, wherein one non-natural amino acid occupies Kabat position 114. 64. The ADC of claim 61, 62 or 63, wherein the anti-HER2 Ab, antibody fragment or variant thereof comprises a light chain. 65. The ADC of claim 64, wherein the light chain has the amino acid sequence of SEQ ID NO: 27. 66. The ADC of claim 64, wherein the light chain has the amino acid sequence of SEQ ID NO: 28, wherein one non-natural amino acid occupies position 121. 67. The ADC of any one of claims 61 to 66, wherein the anti-HER2 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 26. WSGR Ref. No: 31362-826.601 68. The ADC of claim 67, wherein the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 27. 69. The ADC of claim 67, wherein the anti-HER2 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 28. 70. The ADC of any one of claims 61 to 69, wherein each non-natural amino acid is para-acetyl-L- phenylalanine (pAF), and each E comprises an oxime. 71. The ADC of any one of claims 23 to 33, wherein Ab is an anti-PSMA antibody (anti-PSMA Ab), antibody fragment or variant thereof. 72. The ADC of claim 71, wherein the anti-PSMA Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 29 to 45. 73. The ADC of claim 72, wherein the anti-PSMA Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 36, 38, 40, 42 and 44, wherein one non-natural amino acid occupies Kabat position 114. 74. The ADC of claim 73, wherein the anti-PSMA Ab, antibody fragment or variant thereof comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 37, 39, 41, 43 and 45. 75. The ADC of any one of claims 71 to 74, wherein the anti-PSMA Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 36. 76. The ADC of claim 75, wherein the anti-PSMA Ab, antibody fragment or variant thereof, comprises two light chains. 77. The ADC of claim 76, wherein each light chain has the amino acid sequence of SEQ ID NO: 37. 78. The ADC of any one of claims 71 to 77, wherein each non-natural amino acid is para-acetyl-L- phenylalanine (pAF), and each E comprises an oxime. 79. The ADC of any one of claims 23 to 33, wherein Ab is an anti-HER3 antibody (anti-HER3 Ab), antibody fragment or variant thereof. 80. The ADC of claim 79, wherein the anti-HER3 Ab, antibody fragment or variant thereof, comprises one or more amino acid sequences selected from the group consisting of SEQ ID NOs: 46 to 58. WSGR Ref. No: 31362-826.601 81. The ADC of claim 80, wherein the anti-HER3 Ab, antibody fragment or variant thereof, comprises a heavy chain, wherein the heavy chain has the amino acid sequence of SEQ ID NO: 58, wherein one non-natural amino acid occupies Kabat position 114. 82. The ADC of claim 81, wherein the anti-HER3 Ab, antibody fragment or variant thereof, comprises a light chain, wherein the light chain has an amino acid sequence selected from the group consisting of SEQ ID NOs: 47 to 57. 83. The ADC of claim 82, wherein the light chain has the amino acid sequence of SEQ ID NO: 47. 84. The ADC of claim 82, wherein the light chain has the amino acid sequence of SEQ ID NO: 51, wherein one non-natural amino acid occupies position 121. 85. The ADC of any one of claims 79 to 84, wherein the anti-HER3 Ab, antibody fragment or variant thereof, comprises two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58. 86. The ADC of claim 85, wherein the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 47. 87. The ADC of claim 85, wherein the anti-HER3 Ab, antibody fragment or variant thereof, comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51. 88. The ADC of any one of claims 79 to 87, wherein each non-natural amino acid is para-acetyl-L- phenylalanine (pAF), and each E comprises an oxime. 89. The ADC of any one of claims 41 to 88, wherein the ADC is an ADC of Formula (V):
Figure imgf000256_0001
. 90. The ADC of claim 89, wherein L is *-C(O)-O-CH2-O-P(=O)(OH)-O-P(=O)(OH)-O-CH2CH2-, wherein * denotes the connection of L to -N(H)- of Formula (V). 91. The ADC of claim 89 or 90, wherein Ab is an anti-HER3 monoclonal antibody comprising two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 58. WSGR Ref. No: 31362-826.601 92. The ADC of claim 91, wherein the ADC further comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 51. 93. The ADC of claim 89 or 90, wherein Ab is an anti-TROP2 monoclonal antibody comprising two heavy chains, wherein each heavy chain has the amino acid sequence of SEQ ID NO: 5. 94. The ADC of claim 93, wherein the ADC further comprises two light chains, wherein each light chain has the amino acid sequence of SEQ ID NO: 11. 95. A compound of Formula (VII) or (VIII):
Figure imgf000257_0001
pharmaceutically acceptable salt thereof; wherein: L is a linker comprising a phosphate-based moiety, wherein the phosphate-based moiety is a phosphate ester, a pyrophosphate ester, a triphosphate ester, a tetraphosphate ester, a phosphonate, a diphosphonate, a phosporamidate, a pyrophosporamidate, a triphosphoramidate, a tetraphosphoramidate, a phosphorthioate or a diphosphorthioate; and W is a reactive moiety. 96. The compound of claim 95, or a pharmaceutically acceptable salt thereof, wherein W comprises -N3, -OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, -C(O)CH2NH2, an activated ester, –O–NH2, a maleimide, a tetrazine, an alkyne, a cyclooctyne or an (E)-cyclooctene; wherein Rb is H or unsubstituted alkyl, Rc is unsubstituted alkyl, and Rd is H, unsubstituted alkyl or a carboxylic acid protecting group. 97. The compound of claim 95 or 96, or a pharmaceutically acceptable salt thereof, wherein the phosphate-based moiety is a pyrophosphate ester or a diphosphonate. 98. The compound of claim 95, 96 or 97, or a pharmaceutically acceptable salt thereof, wherein L further comprises at least one additional moiety, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, substituted alkylene, – (alkylene–O)nn–, optionally substituted arylene, -O-, -C(O)-, -N(Rw)-, -S(O)0-2- and an amino acid, and combinations thereof, wherein each Rw is independently H or C1-C8 alkyl; wherein each nn is WSGR Ref. No: 31362-826.601 independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; optionally, arylene is phenylene. 99. The compound of claim 98, or a pharmaceutically acceptable salt thereof, wherein each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–, -O-, -C(O)- and -N(Rw)-, and combinations thereof, wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10, and wherein each Rw is independently H or C1-C8 alkyl. 100. The compound of any one of claims 95 to 99, or a pharmaceutically acceptable salt thereof, wherein W is selected from the group consisting of:
Figure imgf000258_0001
-OH, -SH, -NHRb, -C(O)Rc, -C(O)ORd, an activated ester, –O–NH2 and an optionally substituted monocyclic or polycyclic group comprising a cyclooctyne; wherein: Rb is H or unsubstituted C1-C6 alkyl, Rc is unsubstituted C1-C6 alkyl, Rd is H, unsubstituted C1-C6 alkyl or a carboxylic acid protecting group, Rf is H or unsubstituted C1-C6 alkyl, s is 0, 1, 2, 3, 4, 5 or 6, and t is 0, 1, 2, 3, 4, 5 or 6. 101. The compound of claim 100, or a pharmaceutically acceptable salt thereof, wherein the optionally substituted monocyclic or polycyclic group comprising the cyclooctyne is selected from the group consisting of:
Figure imgf000258_0002
102. The compound of any one of claims 95 to 101, or a pharmaceutically acceptable salt thereof, wherein W is –O–NH2. 103. The compound of any one of claims 95 to 102, or a pharmaceutically acceptable salt thereof, wherein: L is independently a phosphate-based moiety bounded with at least one additional moiety; WSGR Ref. No: 31362-826.601 the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)-, -N(Rw)- and an amino acid, and combinations thereof; wherein each Rw is independently H or C1-C8 alkyl; wherein each nn is independently an integer of 1 to 100; optionally, wherein each Rw is independently H or methyl. 104. The compound of any one of claims 95 to 103, or a pharmaceutically acceptable salt thereof, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–U–alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, –C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, WSGR Ref. No: 31362-826.601 –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, –(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and –(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–; wherein: each U is -NH-AA-C(O)-, wherein each AA is independently an amino acid; each J is independently:
Figure imgf000260_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and *, when present, denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). 105. The compound of claim 104, or a pharmaceutically acceptable salt thereof, wherein each U is independently: WSGR Ref. No: 31362-826.601
Figure imgf000261_0001
. 106. The compound of any one of claims 95 to 103, or a pharmaceutically acceptable salt thereof, wherein: L is independently a phosphate-based moiety bounded with at least one additional moiety; the phosphate-based moiety selected from the group consisting of pyrophosphate ester and diphosphonate; and each at least one additional moiety is independently selected from the group consisting of unsubstituted alkylene, –(alkylene–O)nn–,-O-, -C(O)- and -N(Rw)-, and combinations thereof; wherein each nn is independently an integer from 1 to 100; wherein each Rw is independently H or C1-C8 alkyl; optionally, each Rw is independently H or methyl. 107. The compound of any one of claims 95 to 103 and 106, or a pharmaceutically acceptable salt thereof, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene-J–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-C(O)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn-alkylene-N(H)–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–(alkylene-O)nn–J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i–alkylene–J-(alkylene-O)nn–alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, WSGR Ref. No: 31362-826.601 *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–, *–(alkylene–O)nn–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn–alkylene– and *–(alkylene–O)nn–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-(alkylene-O)nn– alkylene–; wherein: each J is independently:
Figure imgf000262_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and WSGR Ref. No: 31362-826.601 * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). 108. The compound of claims 95 to 103 and 106 to 107, or a pharmaceutically acceptable salt thereof, wherein L is selected from the group consisting of: *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-J-alkylene–, *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, *–alkylene-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–J-alkylene–, *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–(O-alkylene)nn– and *–(alkylene–O)nn-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–; wherein: each J is independently:
Figure imgf000263_0001
each alkylene is independently selected from the group consisting of: –(CH2)–, –(CH2)2–, –(CH2)3–, –(CH2)4–, –(CH2)5–, –(CH2)6–, –(CH2)7–, –(CH2)8–, –(CH2)9–, –(CH2)10–, –(CH2)11– and –(CH2)12–; each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10; each i is independently 0 or 1; and * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). 109. The compound of claim 107 or 108, or a pharmaceutically acceptable salt thereof, wherein: each alkylene, when present, is independently –(CH2)–, –(CH2)2– or –(CH2)3–; and each nn is independently 1, 2 or 3. WSGR Ref. No: 31362-826.601 110. The compound of claim 108 or 109, or a pharmaceutically acceptable salt thereof, wherein L is *–C(O)-O-alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O-alkylene)nn–, wherein each nn is independently an integer from 1 to 100; optionally, each nn is independently an integer from 1 to 10, and wherein * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). 111. The compound of claim 108 or 109, or a pharmaceutically acceptable salt thereof, wherein L is *–C(O)-O-CH2-O-P(=O)(OH)-O-P(=O)(OH)-(O-CH2CH2)–, wherein * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). 112. The compound of claim 108 or 109, or a pharmaceutically acceptable salt thereof, wherein L is *–alkylene-O-P(=O)(OH)-O-P(=O)(OH)-(O)i-alkylene–, wherein i is 0 or 1, and wherein * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII). 113. The compound of any one of claims 95 to 103, or a pharmaceutically acceptable salt thereof, wherein L is selected from the group consisting of:
Figure imgf000264_0001
wherein: each m is independently an integer from 1 to 10; each n is independently an integer from 1 to 10; each q is independently an integer from 1 to 10; each i is 0 or 1; WSGR Ref. No: 31362-826.601 each * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII); and each + denotes connection to W. 114. The compound of claim 113, or a pharmaceutically acceptable salt thereof, wherein each m is independently 1, 2 or 3; each n is independently 1, 2 or 3; each q is independently 1, 2 or 3; each i is 0 or 1; each * denotes the connection to (a) -N(H)- of Formula (VII), or (b) -O- of Formula (VIII); and each + denotes connection to W. 115. The compound of any one of claims 104 to 114, or a pharmaceutically acceptable salt thereof, wherein i is 1. 116. The compound of any one of claims 95 to 115, or a pharmaceutically acceptable salt thereof, wherein the compound is a compound of Formula (VII):
Figure imgf000265_0001
; or a pharmaceutically acceptable salt thereof. 117. The compound of claim 116 having the following structure:
Figure imgf000265_0002
or a pharmaceutically acceptable salt thereof. 118. The compound of any one of claims 95 to 115, wherein the compound is a compound of Formula (VIII): WSGR Ref. No: 31362-826.601
Figure imgf000266_0001
; or a pharmaceutically acceptable salt thereof. 119. The compound of claim 118 having the following structure:
Figure imgf000266_0002
or a pharmaceutically acceptable salt thereof. 120. A pharmaceutical composition comprising an ADC of any one of claims 1 to 94 or a compound of any one of claims 95 to 119, and at least one pharmaceutically acceptable adjuvant, binder, buffer, carrier, diluent or excipient. 121. The pharmaceutical composition of claim 120, further comprising a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid, or combination thereof. 122. A method of treating or preventing a disease in a subject, the method comprising administering to the subject an effective amount of an ADC of any one of claims 1 to 94, a compound of any one of claims 95 to 119, or a pharmaceutical composition of claim 120 or claim 121. 123. The method of claim 122, further comprising administering to the subject a therapeutically effective amount of an additional therapeutic agent. 124. The method of claim 123, wherein the additional therapeutic agent is a chemotherapeutic agent, hormonal agent, antitumor agent, immunostimulatory agent, immunomodulator, corticosteroid or a combination thereof. 125. An ADC comprising an anti-HER3 antibody, wherein the ADC comprises at least one amino acid sequence selected from the group consisting of SEQ ID NOs: 46 to 58.
PCT/US2024/022683 2023-04-14 2024-04-02 Drug linkers and antibody conjugates thereof Pending WO2024215515A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202363496236P 2023-04-14 2023-04-14
US63/496,236 2023-04-14

Publications (1)

Publication Number Publication Date
WO2024215515A1 true WO2024215515A1 (en) 2024-10-17

Family

ID=93059976

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2024/022683 Pending WO2024215515A1 (en) 2023-04-14 2024-04-02 Drug linkers and antibody conjugates thereof

Country Status (1)

Country Link
WO (1) WO2024215515A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170021031A1 (en) * 2014-04-10 2017-01-26 Daiichi Sankyo Company, Limited Anti-her3 antibody-drug conjugate
US20190336615A1 (en) * 2017-01-27 2019-11-07 Silverback Therapeutics, Inc. Tumor targeting conjugates and methods of use thereof
WO2021212638A1 (en) * 2020-06-19 2021-10-28 Hangzhou Dac Biotech Co., Ltd. Conjugates of a cell-binding molecule with camptothecin analogs

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170021031A1 (en) * 2014-04-10 2017-01-26 Daiichi Sankyo Company, Limited Anti-her3 antibody-drug conjugate
US20190336615A1 (en) * 2017-01-27 2019-11-07 Silverback Therapeutics, Inc. Tumor targeting conjugates and methods of use thereof
WO2021212638A1 (en) * 2020-06-19 2021-10-28 Hangzhou Dac Biotech Co., Ltd. Conjugates of a cell-binding molecule with camptothecin analogs

Similar Documents

Publication Publication Date Title
CA3094985C (en) Humanized anti-prostate-specific membrane antigen (psma) antibody drug conjugates
AU2024234194A1 (en) Panras inhibitor antibody-drug conjugates and methods of use thereof
WO2024077277A1 (en) Drug linkers and antibody conjugates thereof
WO2023151679A1 (en) Pegylated antibody hydroxyl-bearing drug conjugate
WO2024215515A1 (en) Drug linkers and antibody conjugates thereof
WO2024178360A2 (en) Auristatin analogs and antibody conjugates thereof
JP2024545138A (en) Antibody-drug conjugates with improved affinity, preparation methods thereof, and applications thereof
WO2024178310A1 (en) Trop2-directed antibody-drug conjugates and uses thereof
KR20250134670A (en) anti-CD70 antibody-drug conjugate
HK40118165A (en) Novel anti-prostate-specific membrane antigen (psma) antibody drug conjugates
TW202515620A (en) Targeted treatment of prostate cancers and other tumors by an antibody-drug conjugate
TW202525345A (en) Anti-psma adc conjugate compositions and methods of use thereof
JPWO2020219748A5 (en)
HK40044903B (en) Humanized anti-prostate-specific membrane antigen (psma) antibody drug conjugates
HK40044903A (en) Humanized anti-prostate-specific membrane antigen (psma) antibody drug conjugates

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24789235

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE