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US20220054590A1 - Protoxin-ii variants and methods of use thereof - Google Patents

Protoxin-ii variants and methods of use thereof Download PDF

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US20220054590A1
US20220054590A1 US17/397,586 US202117397586A US2022054590A1 US 20220054590 A1 US20220054590 A1 US 20220054590A1 US 202117397586 A US202117397586 A US 202117397586A US 2022054590 A1 US2022054590 A1 US 2022054590A1
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protoxin
variant
pain
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Mack Flinspach
Alan Wickenden
Ross Fellows
Qinghao Xu
Andrew Piekarz
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Janssen Biotech Inc
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K14/00—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
    • C07K14/435—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
    • C07K14/43504—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans from invertebrates
    • C07K14/43513—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans from invertebrates from arachnidae
    • C07K14/43518—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans from invertebrates from arachnidae from spiders
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K38/00—Medicinal preparations containing peptides
    • A61K38/16—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
    • A61K38/17—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
    • A61K38/1767—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans from invertebrates
    • 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
    • A61K47/56—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 organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule
    • A61K47/59—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 organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyureas or polyurethanes
    • A61K47/60—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 organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyureas or polyurethanes the organic macromolecular compound being a polyoxyalkylene oligomer, polymer or dendrimer, e.g. PEG, PPG, PEO or polyglycerol
    • 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
    • A61K47/62—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 a protein, peptide or polyamino acid
    • A61K47/64—Drug-peptide, drug-protein or drug-polyamino acid conjugates, i.e. the modifying agent being a peptide, protein or polyamino acid which is covalently bonded or complexed to a therapeutically active agent
    • A61K47/643—Albumins, e.g. HSA, BSA, ovalbumin or a Keyhole Limpet Hemocyanin [KHL]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P1/00—Drugs for disorders of the alimentary tract or the digestive system
    • A61P1/18—Drugs for disorders of the alimentary tract or the digestive system for pancreatic disorders, e.g. pancreatic enzymes
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P19/00—Drugs for skeletal disorders
    • A61P19/02—Drugs for skeletal disorders for joint disorders, e.g. arthritis, arthrosis
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P21/00—Drugs for disorders of the muscular or neuromuscular system
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P25/00—Drugs for disorders of the nervous system
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P25/00—Drugs for disorders of the nervous system
    • A61P25/04—Centrally acting analgesics, e.g. opioids
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P29/00—Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P43/00—Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K38/00—Medicinal preparations containing peptides
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2319/00—Fusion polypeptide
    • C07K2319/20—Fusion polypeptide containing a tag with affinity for a non-protein ligand
    • C07K2319/21—Fusion polypeptide containing a tag with affinity for a non-protein ligand containing a His-tag
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2319/00—Fusion polypeptide
    • C07K2319/30—Non-immunoglobulin-derived peptide or protein having an immunoglobulin constant or Fc region, or a fragment thereof, attached thereto
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2319/00—Fusion polypeptide
    • C07K2319/31—Fusion polypeptide fusions, other than Fc, for prolonged plasma life, e.g. albumin
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2319/00—Fusion polypeptide
    • C07K2319/50—Fusion polypeptide containing protease site

Definitions

  • the present invention relates to Protoxin-II variants, synthetic polynucleotides encoding them, and methods of making and using the foregoing.
  • Voltage-gated sodium channels are present in all excitable cells including cardiac and skeletal muscle cells and central and peripheral neurons. In neuronal cells, sodium channels are responsible for amplifying sub-threshold depolarizations and generating the rapid upstroke of the action potential. As such, sodium channels are essential to the initiation and propagation of electrical signals in the nervous system.
  • Sodium channels are typically a complex of various subunits, the principle one being the pore-forming alpha-subunit, which is alone sufficient for function.
  • Nav1.1-Nav1.9 Nine known members of the family of voltage-gated sodium channel alpha subunits exist in humans, Nav1.1-Nav1.9.
  • the Navl.x subfamily can be pharmacologically subdivided into two groups, the tetrodotoxin (TTX)-sensitive and TTX-resistant.
  • Nav1.7 (a.k.a. PN1 or hNE) is encoded by the SCN9A gene, is TTX-sensitive and is primarily expressed in peripheral sympathetic and sensory neurons.
  • Nav1.7 accumulates at nerve fiber endings and amplifies small sub-threshold depolarizations and acts as a threshold channel that regulates excitability.
  • Nav1.7 function is implicated in various pain states, including acute, inflammatory and/or neuropathic pain.
  • gain of function mutations of Nav1.7 have been linked to primary erythemalgia (PE), a disease characterized by burning pain and inflammation of the extremities (Yang et al., J Med Genet 41:171-4, 2004), and paroxysmal extreme pain disorder (PEPD) (Fertleman et al., Neuron 52:767-74, 2006).
  • PE primary erythemalgia
  • PPD paroxysmal extreme pain disorder
  • non-selective sodium channel blockers lidocaine, mexiletine and carbamazepine can provide symptomatic relief in these painful disorders (Legroux-Crespel et al., Ann Dermatol Venereol 130:429-33, 2003; Fertleman et al., Neuron 52:767-74, 2006).
  • CIP congenital indifference to pain
  • Single nucleotide polymorphisms in the coding region of SCN9A have been associated with increased nociceptor excitability and pain sensitivity.
  • a polymorphism rs6746030 resulting in R1150W substitution in human Nav1.7 has been associated with osteoarthritis pain, lumbar discectomy pain, phantom pain, and pancreatitis pain (Reimann et al., Proc Natl Acad Sci USA 107:5148-53, 2010).
  • DRG neurons expressing the R1150W mutant Nav1.7 display increased firing frequency in response to depolarization (Estacion et al., Ann Neurol 66:862-6, 2009).
  • a disabling form of fibromyalgia has been associated with SCN9A sodium channel polymorphism rs6754031, indicating that some patients with severe fibromyalgia may have a dorsal root ganglia sodium channelopathy (Vargas-Alarcon et al., BMC Musculoskelet Disord 13:23, 2012).
  • mice deletion of the SCN9A gene in nociceptive neurons leads to reduction in mechanical and thermal pain thresholds and reduction or abolition of inflammatory pain responses (Nassar et al., Proc Natl Acad Sci USA 101:1270611, 2004). Ablating SCN9A in all sensory neurons abolished mechanical pain, inflammatory pain and reflex withdrawal responses to heat. Deleting SCN9A in both sensory and sympathetic neurons abolished mechanical, thermal and neuropathic pain, and recapitulated the pain-free phenotype seen in humans with Nav1.7 loss-of-function mutations (Minett et al., Nat Commun 3:791, 2012). Nav1.7 inhibitors or blockers may therefore be useful in the treatment of a wide range of pain associated with various disorders.
  • Spider venoms are known to contain a large number of sodium channel blocking peptides, including Huwentoxin-IV (HwTx-IV) (Peng et al., J Biol Chem 277:47564-71, 2002), Protoxin-I, Protoxin-II (Middleton et al., Biochemistry 41:14734-47, 2002) and Phrixotoxin-III (Bosmans et al., Mol Pharmacol 69:419-29, 2006).
  • HwTx-IV Huwentoxin-IV
  • Protoxin-I Protoxin-II
  • Protoxin-III Meddleton et al., Biochemistry 41:14734-47, 2002
  • Phrixotoxin-III Phrixotoxin-III
  • One embodiment of the invention is an isolated Protoxin-II variant that inhibits human Nav1.7 activity, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention is an isolated Protoxin-II variant, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, about 1 ⁇ 10 ⁇ 8 M or less, about 1 ⁇ 10 ⁇ 9 M or less, about 1 ⁇ 10 ⁇ 10 M or less, about 1 ⁇ 10 ⁇ 11 M or less, or about 1 ⁇ 10 ⁇ 12 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7, wherein the Protoxin-II variant has a W7Q and/or a W30L substitution, wherein residue numbering is according to SEQ ID NO: 1.
  • FRET fluorescence resonance energy transfer
  • Another embodiment of the invention is an isolated Protoxin-II variant comprising the amino acid sequence of SEQ ID NOs: 30, 40, 44, 52, 56, 59, 65, 78, 109, 110, 111, 114, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199,
  • Another embodiment of the invention is an isolated Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 422 (GPYCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH); wherein the amino acid sequence has Q at position 7 and L at position 30, when residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention is an isolated fusion protein comprising the Protoxin-II variant of the invention conjugated to a half-life extending moiety.
  • Another embodiment of the invention is an isolated polynucleotide encoding the Protoxin-II variant of the invention.
  • Another embodiment of the invention is a vector comprising the isolated polynucleotide of the invention.
  • Another embodiment of the invention is a host cell comprising the vector of the invention.
  • Another embodiment of the invention is a method of producing the isolated Protoxin-II variant of the invention, comprising culturing the host cell of the invention and recovering the Protoxin-II variant produced by the host cell.
  • Another embodiment of the invention is a pharmaceutical composition
  • a pharmaceutical composition comprising the isolated Protoxin-II variant or fusion protein of the invention and a pharmaceutically acceptable excipient.
  • Another embodiment of the invention is a method of treating Nav1.7-mediated pain in a subject, comprising administering to a subject in need thereof an effective amount of the Protoxin-II variant or the fusion protein of the invention to treat the pain.
  • FIG. 1 shows the genus amino acid sequence of Protoxin-II variants that inhibit Nav1.7 with an IC 50 value of 30 nM or less in a veratridine-induced depolarization inhibition assay. Residue numbering is according to wild-type ProtoxinII of SEQ ID NO: 1. Genus SEQ ID NO: 403.
  • FIG. 2 shows the IC 50 values for Nav1.7 and Nav1.6 inhibition in a QPatch assay, and selectivity of each variant calculated by ratio of IC 50 (Nav1.6)/IC 50 (Nav1.7) obtained in QPatch assay. SE: standard error.
  • FIG. 3 shows the sequences and the genus sequence of Protoxin-II variants that inhibit Nav1.7 with an IC 50 value of 30 nM or less in a veratridine-induced depolarization inhibition assay, and are over 30-fold selective over Nav1.6. Selectivity of each variant was calculated by ratio of IC 50 (Nav1.6)/IC 50 (Nav1.7) obtained in QPatch assay. Residue numbering is according to wild-type Protoxin-II of SEQ ID NO: 1.
  • FIG. 4A shows efficacy of NV1D3034 (NV1D3034-OH) (SEQ ID NO: 78) against CFA-induced thermal hyperalgesia in mice, assessed by measurement of paw withdrawal latency in the Hargreaves test before (pre-CFA) and after CFA injection (0) and 1-day after peptide administration (1).
  • FIG. 4B shows efficacy of NV1D3034 (NV1D3034-OH) (SEQ ID NO: 78) in CFA-induced thermal hyperalgesia in mice, expressed as percent MPE (maximum possible effect) (MPE %) at each dose on day 1 following peptide administration.
  • MPE percent possible effect
  • FIG. 5A shows efficacy of NV1D3368 (NV1D3368-OH) (SEQ ID NO: 198) against CFA-induced thermal hyperalgesia in mice, assessed by measurement of paw withdrawal latency in the Hargreaves test before (pre-CFA) and after CFA injection (0) and 1-day after peptide administration (1). **P ⁇ 0.01 and ****P ⁇ 0.0001 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 5B shows efficacy of NV1D3368 (NV1D3368-OH) (SEQ ID NO: 198) in CFA-induced thermal hyperalgesia in mice, expressed as percent MPE (MPE %) at each dose on day 1 following peptide administration.
  • MPE percent MPE
  • FIG. 6A shows efficacy of NV1D2775-OH (SEQ ID NO: 56) against CFA-induced thermal hyperalgesia in mice, assessed by measurement of paw withdrawal latency in the Hargreaves test before (pre-CFA) and after CFA injection (0) and 1-day after peptide administration (1).
  • FIG. 6B shows efficacy of NV1D2775-OH (SEQ ID NO: 56) in CFA-induced thermal hyperalgesia in mice, expressed as percent MPE (MPE %) at each dose on day 1 following peptide administration. ***P ⁇ 0.001 and ****P ⁇ 0.0001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 6C shows efficacy of NV1D2775-OH (SEQ ID NO: 56) against CFA-induced tactile allodynia in mice. Tactile thresholds of hind paw before (pre-CFA) and after CFA (0) and 1-day after peptide administration (1). ****P ⁇ 0.0001 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 6D shows efficacy of NV1D2775-OH (SEQ ID NO: 56) against CFA-induced tactile allodynia in mice, expressed as percent MPE (MPE %) on day 1 following peptide. ***P ⁇ 0.001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 7A shows time course of NV1D2775-OH mediated reversal of thermal hyperalgesia in the mouse CFA model as assessed by measurement of paw withdrawal latency in the Hargreaves test before and after CFA and at various time points post-peptide administration. **P ⁇ 0.01 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison. Shaded areas indicate compound delivery period (0-24 hr).
  • FIG. 7B shows time course of NV1D2775-OH mediated reversal of tactile allodynia in the mouse CFA model as assessed by measurement of tactile threshold before and after CFA and at various time points post-peptide administration. **P ⁇ 0.01 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison. Shaded areas indicate compound delivery period (0-24hr).
  • FIG. 8 shows that NV1D2775-OH produced significant analgesia in the mouse hotplate test. Thermal withdrawal latency was evaluated at 50 and 55° C. pre- and post-pump implantation. Pump implantation had no impact on the latency in the control PBS group. One day after pump, NV1D2775-OH treated-mice exhibited prolonged latency compared to the PBS group. *P ⁇ 0.05 and ****P ⁇ 0.0001 vs. PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 9 shows that NV1D2775-OH pretreatment protected animals from carrageenan-induced thermal hyperalgesia in mice. Paw withdrawal latencies were measured pre- and on day 1 post-pump before intraplantar carrageenan injection. Latencies were measured again at 2, 3 and 4 hr following carrageenan.
  • FIG. 10 shows the surface representation of the NMR structure of the wild type Protoxin-II.
  • a hydrophobic face shown on left includes residues W5, M6, W7, L23 and W24.
  • a selectivity face is shown on the right and includes residues S11, E12, K14, E17, G18, L29 and W30. Residue numbering is according to SEQ ID NO: 1.
  • FIG. 11A shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) after a single intrathecal (IT) administration in the rat tail flick test. Tail withdrawal latency to a thermal stimulus was measured at the indicated time post-peptide administration.
  • FIG. 11B shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) in the rat tail flick test expressed as percent area under the curve(AUC %) in the first 120min after a single intrathecal (IT) administration.
  • FIG. 11C shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) after a single intrathecal (IT) administration in the rat hot plate test (52.5° C.). The latency of a nociceptive response on a hot plate was measured at the indicated time post-peptide administration.
  • FIG. 11D shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) in the hot plate test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration.
  • AUC % percent area under the curve
  • FIG. 11E shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) in the rat formalin test. Injection of formalin into the rat hindpaw induced a bi-phasic flinching behavior. Total number of flinches in Phase I (0-10 min post formalin) and Phase II (11-60 min post formalin) was measured by an automated device. No statistics were performed in E) due to small group size.
  • FIG. 12A shows efficacy of NV1D2775-OH after a single intrathecal (IT) administration in the rat tail flick test. Tail withdrawal latency to a thermal stimulus was measured at the indicated time post-peptide administration.
  • FIG. 12B shows efficacy of NV1D2775-OH in the rat tail flick test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration.
  • AUC % percent area under the curve
  • FIG. 12C shows efficacy of NV1D2775-OH after a single intrathecal (IT) administration in the rat hot plate test (52.5° C.). The latency of a nociceptive response on a hot plate was measured at the indicated time post-peptide administration.
  • FIG. 12D shows efficacy of NV1D2775-OH in the rat hot plate test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. **P ⁇ 0.01 and ****P ⁇ 0.0001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 12E shows efficacy of NV1D2775-OH in the formalin test.
  • Injection of formalin into the rat hindpaw induced a bi-phasic flinching behavior.
  • Total number of flinches in Phase I (0-10 min post formalin) and Phase II (11-60 min post formalin) was measured by an automated device. **P ⁇ 0.01 vs PBS, phase I, *P ⁇ 0.05 vs PBS, phase II, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 13A shows efficacy of NV1D3034-OH after a single intrathecal (IT) administration in the rat tail flick test. Tail withdrawal latency to a thermal stimulus was measured at the indicated time post-peptide administration.
  • FIG. 13B shows efficacy of NV1D3034-OH in the rat tail flick test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. ***P ⁇ 0.005 vs PBS, t-test.
  • FIG. 13C shows efficacy of NV1D3034-OH after a single intrathecal (IT) administration in the rat hot plate test (52.5° C.). The latency of a nociceptive response on a hot plate was measured at the indicated time post-peptide administration.
  • FIG. 13D shows efficacy of NV1D3034-OH in the rat hot plate test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. **P ⁇ 0.01 vs PBS, t-test.
  • FIG. 13E shows efficacy of NV1D3034-OH in the rat formalin test. Injection of formalin into the rat hindpaw induced a bi-phasic flinching behavior. Total number of flinches in Phase I (0-10 min post formalin) and Phase II (11-60 min post formalin) was measured by an automated device. *P ⁇ 0.05 vs PBS, phase I, **P ⁇ 0.01 vs PBS, phase II, t-test.
  • FIG. 14 shows the amino acid alignment of the Family 3 cysteine knot toxin peptides(SEQ ID NOS 738-740, 1 and 741-755, respectively, in order of appearance).
  • polypeptide means a molecule that comprises at least two amino acid residues linked by a peptide bond to form a polypeptide. Small polypeptides of less than 50 amino acids may be referred to as “peptides.” Polypeptides may also be referred as “proteins.”
  • complementary sequence means a second isolated polynucleotide sequence that is antiparallel to a first isolated polynucleotide sequence and that comprises nucleotides complementary to the nucleotides in the first polynucleotide sequence.
  • vector means a non-natural polynucleotide capable of being duplicated within a biological system or that can be moved between such systems.
  • Vector polynucleotides typically contain a cDNA encoding a protein of interest and additional elements, such as origins of replication, polyadenylation signal or selection markers, that function to facilitate the duplication or maintenance of these polynucleotides in a biological system.
  • additional elements such as origins of replication, polyadenylation signal or selection markers, that function to facilitate the duplication or maintenance of these polynucleotides in a biological system.
  • Examples of such biological systems may include a cell, virus, animal, plant, and reconstituted biological systems utilizing biological components capable of duplicating a vector.
  • the polynucleotide comprising a vector may be DNA or RNA molecules or a hybrid of these.
  • expression vector means a vector that can be utilized in a biological system or a reconstituted biological system to direct the translation of a polypeptide encoded by a polynucleotide sequence present in the expression vector.
  • variant refers to a polypeptide or a polynucleotide that differs from wild type Protoxin-II polypeptide of SEQ ID NO: 1 or the polynucleotide encoding the wild type Protoxin-II having the sequence of SEQ ID NO: 107 by one or more modifications for example, substitutions, insertions or deletions of nucleotides or amino acids.
  • residues that are substituted in the Protoxin-II variants are numbered corresponding to their position in the wild-type Protoxin-II of SEQ ID NO: 1.
  • Y1A in the specification refers to the substitution of tyrosine at residue position that corresponds to the position 1 in the wild type Protoxin-II of SEQ ID NO:1 with alanine.
  • Codons encoding the initiator methionine may or may not be present in cDNA.
  • cDNA may be synthesized for example by reverse transcription or synthetic gene assembly.
  • Synthetic or “non-natural” as used herein refers to a polynucleotide or a polypeptide molecule not present in nature.
  • Nav1.7 (also referred to as hNE or PN1) or “hNav1.7” as used herein refers to the well-known human sodium channel protein type 9 subunit alpha having a sequence shown in GenBank accession number NP 002968.1 and in SEQ ID NO: 79.
  • wild type Protoxin-II or wild type ProTx-II as used herein refers to the tarantula Thrixopelma pruriens (Peruvian green velvet tarantula) toxin peptide having the amino acid sequence YCQKWMWTCDSERKCCEGMVCRLWCKKKLW-COOH (SEQ ID NO: 1) as described in Middleton et al., Biochemistry 41(50):14734-47, 2002.
  • Recombinant Protoxin-II refers to the recombinant Protoxin-II obtained from expression and subsequent cleavage of a Protoxin-II fusion protein having the sequence of GPYCQKWMWTCDSERKCCEGMVCRLWCKKKLW-OH as shown in SEQ ID NO: 2.
  • Recombinant Protoxin-II incorporates a two amino acid N-terminal extension (residues G and P) when compared to the wild type Protoxin-II.
  • “Blocks human Nav1.7 activity” or “inhibits human Nav1.7 activity” as used herein refers to the ability of the Protoxin-II variant of the invention to reduce membrane depolarization induced by veratridine (3-veratroylveracevine) with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less in a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET), where veratridine-induced depolarization is measured as a reduction in FRET signal using DISBAC2(3) ([bis-(1,3-diethylthiobarbituric acid) trimethine oxonol]) as an acceptor and PTS18 (trisodium 8-octadecyloxypyrene-1,3,6-trisulfonate) as a donor by exciting the donor at 390-420 nm and measuring FRET at 515-575 nm in a cell line stably expressing human Nav1.7.
  • FRET flu
  • Protoxin-II variants of the invention may also be measured using QPatch electrophysiology at single or several Protoxin-II variant concentrations according to protocol described in Example 3.
  • the Protoxin-II variant of the invention blocks human Nav1.7 activity when it inhibits Nav1.7 currents measured using QPatch by at least about 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when using the assay protocol described in Example 3.
  • Veratridine-induced depolarization inhibition assay refers to the assay described in Example 3.
  • QPatch assay or “QPatch electrophysiology assay” as used herein refers to the assay described in Example 3.
  • substantially identical means that the two Protoxin-II variant amino acid sequences being compared are identical or have “insubstantial differences.” Insubstantial differences are substitutions of 1, 2, 3, 4, 5, 6, or 7 amino acids in the Protoxin-II variant amino acid sequence that do not adversely affect peptide properties.
  • Amino acid sequences substantially identical to the Protoxin-II variants disclosed herein are within the scope of the application. In some embodiments, the sequence identity can be about 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher.
  • Percent identity can be determined for example by pairwise alignment using the default settings of the AlignX module of Vector NTI v.9.0.0 (Invitrogen, Carlsbad, Calif.).
  • the protein sequences of the present invention may be used as a query sequence to perform a search against public or patent databases, for example, to identify related sequences.
  • Exemplary programs used to perform such searches are the XBLAST or BLASTP programs (http //www ncbi nlm/nih gov), or the GenomeQuestTM (GenomeQuest, Westborough, Mass.) suite using the default settings.
  • the present invention provides isolated Protoxin-II (ProTx-II) variant polypeptides that inhibit human Nav1.7 activity, polynucleotides encoding them, vectors, host cells, and methods of using the polynucleotides and polypeptides of the invention.
  • the polypeptides of the invention inhibit depolarization/currents resulting from Nav1.7 activation, and therefore may be useful in the treatment of various conditions associated with pain and conditions associated with sensory or sympathetic neuron dysfunction.
  • the variants of the invention are potent inhibitors of Nav1.7.
  • the current invention is based, at least in part, on the finding that certain residue substitutions in Protoxin-II enhance selectivity, synthetic yield and/or homogeneity without adversely affecting the potency of the generated Protoxin-II variants, specifically W7 and M19, and additionally residues Y1 and S11, and further additionally residues E12, R22 and (residue numbering according to SEQ ID NO: 1).
  • substitutions at positions W7 and W30 enhance the Protoxin-II variant folding and improve yield.
  • substitutions at positions S11, E12, K14, E17, G18, L29 and W30 improve selectivity of the resulting Protoxin-II variants to Nav1.7.
  • One embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, about 1 ⁇ 10 ⁇ 8 M or less, about 1 ⁇ 10 ⁇ 9 M or less, about 1 ⁇ 10 ⁇ 10 M or less, about 1 ⁇ 10 ⁇ 11 M or less, or about 1 ⁇ 10 ⁇ 12 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • FRET fluorescence resonance energy transfer
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, about 1 ⁇ 10 ⁇ 8 M or less, about 1 ⁇ 10 ⁇ 9 M or less, about 1 ⁇ 10 ⁇ 10 M or less, about 1 ⁇ 10 ⁇ 11 M or less, or about 1 ⁇ 10 ⁇ 12 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1.
  • FRET fluorescence resonance energy transfer
  • Another embodiment of the invention of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant that inhibits human Nav1.7 activity, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1.
  • the Protoxin-II variant has a W7Q substitution.
  • the Protoxin-II variant has a W30L substitution.
  • the Protoxin-II variant has a W7Q and a W30L substitution.
  • the Protoxin-II variant inhibits Nav1.7 activity by at least 25%, 30%, 35%, 40%, 45%,50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when the Nav1.7 activity is measured using QPatch assay according to protocol described in Example 3.
  • the Protoxin-II variant has a substitution at one or more residue positions Y1, W7, S11, E12, K14, E17, G18, R22, L29 and W30, when residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence YCQKWMQTCDSERKCCEGMVCRLWCKKKLW-COOH (SEQ ID NO: 424); wherein residue Y1, S11, E12, K14, E17, G18, L29 and/or W30 is substituted with any other amino acid shown in Table 1 or a non-natural amino acid, optionally having an N-terminal extension or a C-terminal extension.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence YCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH (SEQ ID NO: 425); wherein residue Y1, S11, E12, K14, E17, G18, M19, L29 and/or W30 is substituted with any other amino acid shown in Table 1 or a non-natural amino acid, optionally having an N-terminal extension or a C-terminal extension.
  • the Protoxin-II variant of the invention described herein, including in the numbered embodiments listed below, contains at least one a non-natural amino acid.
  • Non-natural amino acids include amino ⁇ -alanine (( ⁇ -Ala) and other omega-amino acids such as 3-aminopropionic acid (Dap), 2,3-diaminopropionic acid (Dpr), 4-aminobutyric acid and so forth; ⁇ -aminoisobutyric acid (Aib); ⁇ -aminohexanoic acid (Aha); ⁇ -aminovaleric acid (Ava); N-methylglycine or sarcosine (MeGly); ornithine (Om); citrulline (Cit); t-butylalanine (t-BuA); t-butylglycine (t-BuG); Nmethylisoleucine (Melle); phenylglycine (Phg); cyclohexylalanine (Cha); norleucine (Nle); 2-naphthylalanine (2-Nal); 4-chlorophenylalanine (Phe(4-C
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • X 1 is G, P, A or deleted
  • X 2 is P, A or deleted
  • X 3 is S, Q, A, R or Y;
  • X 4 is Q, R, K, A, S or Y;
  • X 5 is K, S, Q or R;
  • X 6 is M or F
  • X 7 is T, S, R, K or Q
  • X 8 is D, T or asparagyl-4-aminobutane
  • X 9 is S, A, R, I or V;
  • X 10 is E, R, N, K, T, Q, Y or glutamyl-4-aminobutane
  • X 11 is R or K
  • X 12 is K, Q, S, A or F
  • X 13 is E, Q, D, L, N or glutamyl-4-aminobutane
  • X 14 is G, Q or P;
  • X 15 is M or F
  • X 16 is V or S
  • X 17 is R, T or N-omega methyl L-arginine
  • X 18 is K or R
  • X 19 is W or L
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • X 1 is G, P, A or deleted
  • X 2 is P, A or deleted
  • X 3 is S, Q, A, R or Y;
  • X 4 is S, A, R, I or V;
  • X 5 is E, R, N, K, T, Q, Y or glutamyl-4-aminobutane
  • X 6 is K, Q, S, A or F
  • X 7 is E, Q, D, L, N or glutamyl-4-aminobutane
  • X 8 is G, Q or P
  • X 9 is M or F
  • X 10 is L, V;
  • X 11 is W or L.
  • the Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • FRET fluorescence resonance energy transfer
  • the Protoxin-II variant inhibits Nav1.7 activity by at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when the Nav1.7 activity is measured using QPatch assay according to protocol described in Example 3.
  • the N-terminal extension comprises the amino acid sequences of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
  • the C-terminal extension comprises the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
  • the N-terminal and/or the C-terminal extension is conjugated to the Protoxin-II variant via a linker.
  • the linker comprises the amino acid sequence of SEQ ID NOs: 383, 392, 398, 399, 400, 401 or 402.
  • the N-terminal extension consists of the amino acid sequences of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
  • the C-terminal extension consists of the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
  • the linker consists of the amino acid sequence of SEQ ID NOs: 383, 392, 398, 399, 400, 401 or 402.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • X 1 is G, P, A or deleted
  • X 2 is P, A or deleted
  • X 3 is S, Q, A, R or Y;
  • X 4 is Q, R, K, A or S;
  • X 5 is K, S, Q or R;
  • X 6 is M or F
  • X 7 is T, S, R, K or Q
  • X 8 is D or T
  • X 9 is S, A or R;
  • X 10 is E, R, N, K, Tor Q;
  • X 11 is R or K
  • X 12 is K, Q, S or A
  • X 13 is E, Q or D
  • X 14 is G or Q
  • X 15 is V or S
  • X 16 is R or T
  • X 17 is K or R
  • polypeptide inhibits human Nav1.7 activity with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • FRET fluorescence resonance energy transfer
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below are potent Nav1.7 inhibitors.
  • Recombinant Protoxin-II (SEQ ID NO: 2) has an IC 50 value of about 4 ⁇ 10 ⁇ 9 M for human Nav1.7 in a veratridine-induced depolarization inhibition assay measuring decline in FRET (fluorescence resonance energy transfer) in cells stably expressing Nav1.7 using FLIPR® Tetra instrument (Molecular Devices) using experimental details described in Example 3.
  • a Protoxin-II variant is “a potent” Nav1.7 inhibitor when the IC 50 value in the assay described above and in Experiment 3 is about 30 ⁇ 10 ⁇ 9 M or less, i.e. within 10 fold of recombinant Protoxin-II.
  • an IC 50 of 30 ⁇ 10 ⁇ 9 M is identical to IC 50 of 3.0 ⁇ 10 ⁇ 8 M.
  • Protoxin-II variant polypeptides of the invention disclosed herein may be produced by chemical synthesis, such as solid phase peptide synthesis, on an automated peptide synthesizer.
  • the polypeptides of the invention may be obtained from polynucleotides encoding the polypeptides by the use of cell-free expression systems such as reticulocyte lysate based expression systems, or by recombinant expression systems. Those skilled in the art will recognize other techniques for obtaining the polypeptides of the invention.
  • the Protoxin-II variants of the invention are generated by expressing them as human serum albumin (HSA) fusion proteins utilizing a glycine-rich linker such as (GGGGS) 4 (SEQ ID NO:80) or (GGGGS) 6 (SEQ ID NO: 81) coupled to a protease cleavable linker such as a recognition sequence for HRV3C protease (Recombinant type 14 3C protease from human rhinovirus) LEVLFQGP (HRV3C linker) (SEQ ID NO: 82), and cleaving the expressed fusion proteins with the HRV3C protease to release the recombinant Protoxin-II variant peptides.
  • HSA human serum albumin
  • a glycine-rich linker such as (GGGGS) 4 (SEQ ID NO:80) or (GGGGS) 6 (SEQ ID NO: 81) coupled to a protease cleavable linker such
  • Protoxin-II variants of the invention disclosed herein may be purified using methods described herein.
  • Protoxin-II variants of the invention expressed as HSA fusion proteins and cleaved with HRV3C protease may be purified using sold phase extraction (SPE) as described herein.
  • SPE sold phase extraction
  • Protoxin-II variants disclosed herein including in the numbered embodiments listed below optionally having N-terminal and/or C-terminal extensions, and Protoxin-II variant fusion proteins is typically achieved at the nucleic acid level.
  • the polynucleotides may be synthesized using chemical gene synthesis according to methods described in U.S. Pat. Nos. 6,521,427 and 6,670,127, utilizing degenerate oligonucleotides to generate the desired variants, or by standard PCR cloning and mutagenesis. Libraries of variants may be generated by standard cloning techniques to clone the polynucleotides encoding the Protoxin-II variants into the vector for expression.
  • the Protoxin-II variants of the invention disclosed herein may incorporate additional N- and/or C-terminal amino acids when compared to the wild type Protoxin-II of SEQ ID NO: 1, for example resulting from cloning and/or expression schemes.
  • cleavage from HSA after expression of the variant as HSA-linker-HRV3C cleavable peptide-Protoxin-II variant fusion protein may result in the incorporation of additional two residues to the N-terminus of each Protoxin-II variant, such as G and P.
  • Protoxin-II variants of the invention disclosed herein are tested for their ability to inhibit human Nav1.7 using methods described herein.
  • An exemplary assay is a veratridine-induced depolarization inhibition assay measuring decline in FRET (fluorescence resonance energy transfer) in cells stably expressing Nav1.7.
  • Another exemplary assay employs electrophysiological recordings to measure changes in Nav1.7-mediated currents using well known patch clamp techniques and as described herein.
  • Another embodiment of the invention is an isolated Protoxin-II variant disclosed herein, including in the numbered embodiments listed below comprising the amino acid sequence of SEQ ID NOs: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,
  • the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may inhibit human Nav1.7 with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, about 1 ⁇ 10 ⁇ 8 M about 1 ⁇ 10 ⁇ 9 or less, about 1 ⁇ 10 ⁇ 19 M or less, about 1 ⁇ 10 ⁇ 11 M or less, or about 1 ⁇ 10 ⁇ 12 M or less.
  • variants demonstrating the range of IC 50 values are variants having amino acid sequences shown in SEQ ID NOs: 30, 40, 44, 52, 56, 59, 65, 78, 109, 110, 111, 114, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199,
  • the Protoxin-II variant inhibits Nav1.7 activity by at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when the Nav1.7 activity is measured using QPatch assay according to protocol described in Example 3.
  • variants inhibiting Nav1.7 activity by at least 25% in a QPatch assay are variants having amino acid sequences shown in SEQ ID NOs: 109, 133, 408, 409, 410, 412, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 434, 436, 437, 438, 439, 440, 441, 442, 444, 446, 447, 448, 450, 452, 453, 455, 456, 459, 460, 461, 462, 463, 464, 465, 466, 468, 469, 470, 471, 473, 474, 476, 477, 478, 479, 480, 482, 483, 485, 486, 487, 490, 491, 492, 494, 495, 496, 497, 498, 499, 500, 502, 504, 505, 507, 508, 510, 511, 512, 514, 516, 5
  • Table 2 Table 3, Table 14, and Table 18 show the sequences of select Protoxin-II variants.
  • the isolated Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of about 3 ⁇ 10 ⁇ 8 M or less.
  • the isolated Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of between about 3 ⁇ 10 ⁇ 8 M to about 1 ⁇ 10 ⁇ 9 M.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the amino acid sequence
  • X 1 is Q, R, K, A or S;
  • X 2 is K, S, Q or R;
  • X 3 is M or F
  • X 4 is T, S, R, K or Q
  • X 5 is D or T
  • X 6 is S, A or R;
  • X 7 is E, R, N, K, T or Q;
  • X 8 is R or K
  • X 9 is K, Q, S or A
  • X 10 is E, Q or D
  • X 11 is G or Q
  • X 12 is V or S
  • X 13 is R or T
  • X 14 is K or R.
  • Exemplary Protoxin-II variants that inhibit human Nav1.7 activity with an IC 50 value of about 30 ⁇ 10 ⁇ 9 M or less are variants comprising the amino acid sequences of SEQ ID NOs: 56, 78, 111, 114, 117, 118, 119, 122, 123, 129, 130, 131, 132, 133, 134, 135, 136, 138, 139, 140, 141, 142, 145, 146, 147, 149, 150, 151, 152, 153, 154, 156, 158, 159, 165, 172, 173, 175, 177, 178, 183, 184, 185, 186, 189, 190, 193, 197, 199, 207, 210, 211, 216, 217, 224, 266, 273, 282, 335, 408, 409, 410, 422, 424, 425, 426, 427 and 428.
  • the isolated Protoxin-II variant selectively inhibits human Nav1.7.
  • the Protoxin-II variants of the invention may be more selective towards Nav1.7 when compared to the recombinant Protoxin-II (SEQ ID NO: 2).
  • recombinant Protoxin-II has an IC 50 of about 2.2 ⁇ 10 ⁇ 9 M for Nav1.7 and an IC 50 of about 62 ⁇ 10 ⁇ 9 M for Nav1.6, and therefore the ratio of IC 50 for Nav1.6 to IC 50 for Nav1.7 is about 28 fold.
  • “Selectivity” or “selective” or “more selective” or “selectively blocks” or “selectively inhibits” when used herein refers to a Protoxin-II variant that has a ratio of IC 50 for Nav1.6 to IC 50 for Nav1.7 (1C50(Nav1.6)/IC 50 (Nav1.7)) equal or over about 30.
  • IC 50 for Nav1.6 may be assayed in a QPatch electrophysiology assay using cell lines stably expressing Nav1.6 using similar methods to those described for Nav1.7.
  • Residue positions in Protoxin-II that can be mutagenized to improve selectivity include residues 7, 11, 12, 14, 17, 18 and 19, and optionally residues 1, 20, 22 and 26 (residue numbering according to SEQ ID NO: 1).
  • Exemplary substitutions to improve selectivity are Y1Q, W7Q, S11R, S11A, E12T, M19F, V20S, R22T, and K26R.
  • Exemplary Protoxin-II variants with improved selectivity are variants of SEQ ID NOs: 56, 59, 65, 78, 111, 114, 117, 118, 119, 121, 122, 123, 129, 130, 133, 150, 190, 217, 281, 324, 325 or 326.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • X 1 is Y, Q, A, S or R;
  • X 2 is T or S
  • X 3 is S, R or A
  • X 4 is E, T or N;
  • X 5 is E or Q
  • X 6 is V or S
  • X 7 is R or T
  • X 8 is K or R
  • Protoxin-II variant inhibits human Nav1.7 activity with an IC 50 value of about 3 ⁇ 10 ⁇ 8 M or less, and selectively inhibits human Nav1.7.
  • the isolated Protoxin-II variant comprises the sequence
  • X 1 is T or S
  • X 2 is S, R or A
  • X 3 is E, T or N;
  • X 4 is E or Q
  • X 5 is V or S
  • X 6 is R or T
  • X 7 is K or R.
  • Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 422 (GPYCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH); wherein
  • Protoxin-II variants having substitutions W7Q and W30L have improved folding, yield and selectivity when compared to the wild type Protoxin-II.
  • Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 78 (GPQCQKWMQTCDRERKCCEGFVCTLWCRKKLW-COOH); wherein
  • the isolated Protoxin-II variant has a carboxylic acid, amide, methylamide or butylamide group at the C-terminus.
  • C-terminal modifications may be generated via routine synthetic methods.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated fusion protein comprising the Protoxin-II variant of SEQ ID NOs: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,
  • Such second polypeptides may be well known leader or secretory signal sequences, or synthetic sequences resulting for example from cloning steps, or tags such as hexahistidine tag (SEQ ID NO: 108). Such second polypeptide may be a half-life extending moiety.
  • the isolated fusion protein comprises the Protoxin-II variant of the invention conjugated to a half-life extending moiety.
  • Exemplary half-life extending moieties that may be used include well known human serum albumin, transthyretin (TTR), a thyroxine-binding globulin (TGB), albumin-binding domains, or an Fc or fragments thereof.
  • TTR transthyretin
  • TGB thyroxine-binding globulin
  • Fc or fragments thereof include well known human serum albumin, transthyretin (TTR), a thyroxine-binding globulin (TGB), albumin-binding domains, or an Fc or fragments thereof.
  • Biologically suitable polymers or copolymers may also be used, for example ethylene glycol or polyethylene glycol (PEG) molecules, such as PEG5000 or PEG20000, dextran, polylysine, fatty acids and fatty acid esters of different chain lengths, for example laurate, myristate, stearate, arachidate, behenate, oleate, arachidonate, octanedioic acid, tetradecanedioic acid, octadecanedioic acid, docosanedioic acid, and the like, octane, or carbohydrates (dextran, cellulose, oligo- or polysaccharides).
  • PEG polyethylene glycol
  • moieties that can improve biodistribution include polyamination (putrescine, spermine, or spermidine etc.), halogenation (chlorine, bromine, fluorine, iodine), and glycosylation. These moieties may be direct fusions with the Protoxin-II variant polypeptides and may be generated by standard cloning and expression techniques. Alternatively, well known chemical coupling methods may be used to attach the moieties to recombinantly produced Protoxin-II variants of the invention. Alternatively, moieties can be incorporated as non-coded amino acids during solid phase peptide synthesis.
  • the half-life extending moiety of the fusion protein of the invention is human serum albumin, variants of human serum albumin, albumin binding domain (ABD), or polyethylene glycol (PEG).
  • the half-life extending moiety of is conjugated to the Protoxin-II variant via a linker.
  • Suitable linkers are well known and include linkers having the sequence shown in SEQ ID NOs: 80 or 81.
  • Exemplary fusion proteins incorporating Protoxin-II variants of the invention are those having the polypeptide sequence of SEQ ID NOs: 83, 85, 87, 89, 91, 93, 95, 97, 99, 101 or 103.
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below incorporating additional moieties may be compared for functionality by several well-known assays. For example, pharmacokinetic properties of Protoxin-II variants coupled to PEG may be evaluated in well known in vivo models.
  • Protoxin-II variants and Protoxin-II variant fusion proteins are within the scope of the invention. Additional substitutions to the Protoxin-II variants of the invention can be made as long as the resulting variant or the fusion protein retains similar characteristics when compared to the parent peptide. Exemplary modifications are for example conservative substitutions that will result in Protoxin-II variants with similar characteristics to those of the parent molecules. Conservative replacements are those that take place within a family of amino acids that are related in their side chains.
  • Genetically encoded amino acids can be divided into four families: (1) acidic (aspartate, glutamate); (2) basic (lysine, arginine, histidine); (3) nonpolar (alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan); and (4) uncharged polar (glycine, asparagine, glutamine, cysteine, serine, threonine, tyrosine). Phenylalanine, tryptophan, and tyrosine are sometimes classified jointly as aromatic amino acids.
  • the amino acid repertoire can be grouped as (1) acidic (aspartate, glutamate); (2) basic (lysine, arginine histidine), (3) aliphatic (glycine, alanine, valine, leucine, isoleucine, serine, threonine), with serine and threonine optionally grouped separately as aliphatic-hydroxyl; (4) aromatic (phenylalanine, tyrosine, tryptophan); (5) amide (asparagine, glutamine); and (6) sulfur-containing (cysteine and methionine) (Stryer (ed.), Biochemistry, 2nd ed, WH Freeman and Co., 1981).
  • Non-conservative substitutions can be made to the Protoxin-II variants that involve substitutions of amino acid residues between different classes of amino acids to improve properties of the Protoxin-II variants and Protoxin-II variant fusion proteins.
  • Whether a change in the amino acid sequence of a polypeptide or fragment thereof results in a functional homolog can be readily determined by assessing the ability of the modified polypeptide or fragment to produce a response in a fashion similar to the unmodified polypeptide or fragment using the assays described herein.
  • Peptides, polypeptides or proteins in which more than one replacement takes place can readily be tested in the same manner.
  • Another embodiment of the invention is an isolated family 3 spider venom cysteine knot peptide comprising at least one substitution at a position corresponding to position W7 and/or W30 of SEQ ID NO: 1.
  • Family 3 spider toxins include 14 toxins with conserved C-terminal region, including, in addition to Protoxin-II, ⁇ -TRTX-Gr2b, ⁇ -TRTX-Gr2c, ⁇ -TRTX-Ps1a, ⁇ -TRTX-Ps1b, ⁇ -TRIX-Gr1b, ⁇ -TRTX-Cj2a, ⁇ -TRIX-Cj2b, ⁇ -TRTX-Ec2c, ⁇ -TRIX-Gr1a, ⁇ -TRTX-Ec2b, ⁇ -TRTX-Ec2a and ⁇ / ⁇ -TRTX-Cj2a and those shown in FIG. 14 .
  • Substitutions at positions W7 and/or W30 are expected to improve folding of the
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated synthetic polynucleotide comprising a polynucleotide encoding the Protoxin-II variant of the invention.
  • Certain exemplary synthetic polynucleotides are disclosed herein, however, other synthetic polynucleotides which, given the degeneracy of the genetic code or codon preferences in a given expression system, encode the Protoxin-II variants and Protoxin-II variant fusion proteins of the invention are also within the scope of the invention.
  • Exemplary synthetic polynucleotides are for example polynucleotide sequences shown in SEQ ID NOs: 84, 86, 88, 90, 92, 94, 96, 98, 100, 102 and 104, which encode the ProtoxinII variant fusion proteins of the invention.
  • the synthetic polynucleotide sequences encoding the Protoxin-II variants or fusion proteins of the invention can be operably linked to one or more regulatory elements, such as a promoter and enhancer, that allow expression of the nucleotide sequence in the intended host cell.
  • the synthetic polynucleotide may be a cDNA.
  • the polynucleotides of the invention may be produced by chemical synthesis such as solid phase polynucleotide synthesis on an automated polynucleotide synthesizer.
  • the polynucleotides of the invention may be produced by other techniques such as PCR based duplication, vector based duplication, or restriction enzyme based DNA manipulation techniques. Techniques for producing or obtaining polynucleotides of known sequences are well known.
  • the polynucleotides of the invention may also comprise at least one non-coding sequence, such as transcribed but not translated sequences, termination signals, ribosome binding sites, mRNA stabilizing sequences, introns and polyadenylation signals.
  • the polynucleotide sequences may also comprise additional sequences encoding additional amino acids. These additional polynucleotide sequences may, for example, encode a marker or well-known tag sequences such as a hexa-histidine (SEQ ID NO: 108) or a HA tag which facilitate the purification of fused polypeptides.
  • a vector comprising the polynucleotide of the invention.
  • Such vectors may be plasmid vectors, viral vectors, vectors for baculovirus expression, transposon based vectors or any other vector suitable for introduction of the polynucleotide of the invention into a given organism or genetic background by any means.
  • polynucleotides encoding the Protoxin-II variants or the Protoxin-II variant fusion proteins of the invention are inserted into an expression vector and may be operably linked to control sequences in the expression vector to ensure efficient expression, such as signal sequences, promoters (e.g.
  • the vector Once the vector has been incorporated into the appropriate host, the host is maintained under conditions suitable for high level expression of the proteins encoded by the incorporated polynucleotides.
  • Suitable expression vectors are typically replicable in the host organisms either as episomes or as an integral part of the host chromosomal DNA. Commonly, expression vectors contain selection markers such as ampicillin-resistance, hygromycin-resistance, tetracycline resistance, kanamycin resistance or neomycin resistance to permit detection of those cells transformed with the desired DNA sequences.
  • Suitable promoter and enhancer elements are known in the art.
  • suitable promoters include, but are not limited to, lacl, lacZ, T3, T7, gpt, lambda P and trc.
  • suitable promoters include, but are not limited to, light and/or heavy chain immunoglobulin gene promoter and enhancer elements; cytomegalovirus immediate early promoter; herpes simplex virus thymidine kinase promoter; early and late SV40 promoters; promoter present in long terminal repeats from a retrovirus; mouse metallothionein-I promoter; and various art-known tissue specific promoters.
  • a suitable promoter is a constitutive promoter such as an ADH1 PGK1, ENO or PYK1 promoter and the like, or a regulatable promoter such as a GALL or GAL10 promoter. Selection of the appropriate vector and promoter is well within the level of ordinary skill in the art.
  • Bacterial pBs, phagescript, PsiX 174 , pBluescript SK, pBs KS, pNH8a, pNH16a, pNH18a, pNH46a (Stratagene, La Jolla, Calif., USA); pTrc99A, pKK223-3, pKK233-3, pDR540, and pRIT5 (Pharmacia, Uppsala, Sweden).
  • Eukaryotic pWLneo, pSV2cat, pOG44, PXR1, pSG (Stratagene) pSVK3, pBPV, pMSG and pSVL (Pharmacia).
  • An exemplary vector for expression of the Protoxin-II variants or Protoxin-II variant fusion proteins is a vector having ampicillin-resistance selection marker, CMV promoter, CMV intron, signal peptide, neomycin resistance, f1 origin of replication, SV40 polyadenylation signal, and cDNA encoding the Protoxin-II variant or the Protoxin-II variant fusion protein of the invention.
  • host cell refers to a cell into which a vector has been introduced. It is understood that the term host cell is intended to refer not only to the particular subject cell but also to the progeny of such a cell. Because certain modifications may occur in succeeding generations due to either mutation or environmental influences, such progeny may not be identical to the parent cell, but are still included within the scope of the term “host cell” as used herein.
  • host cells may be eukaryotic cells, prokaryotic cells, plant cells or archaeal cells.
  • Escherichia coli bacilli, such as Bacillus subtilis , and other enterobacteriaceae, such as Salmonella, Serratia , and various Pseudomonas species, are examples of prokaryotic host cells.
  • Other microbes, such as yeast are also useful for expression. Saccharomyces (e.g., S. cerevisiae ) and Pichia are examples of suitable yeast host cells.
  • Exemplary eukaryotic cells may be of mammalian, insect, avian or other animal origins.
  • Mammalian eukaryotic cells include immortalized cell lines such as hybridomas or myeloma cell lines such as SP2/0 (American Type Culture Collection (ATCC), Manassas, Va., CRL-1581), NSO (European Collection of Cell Cultures (ECACC), Salisbury, Wiltshire, UK, ECACC No. 85110503), FO (ATCC CRL-1646) and Ag653 (ATCC CRL-1580) murine cell lines.
  • An exemplary human myeloma cell line is U266 (ATTC CRL-TIB-196).
  • Other useful cell lines include those derived from Chinese Hamster Ovary (CHO) cells such as CHO-K1SV (Lonza Biologics, Walkersville, Md.), CHO-K1 (ATCC CRL-61) or DG44.
  • a polynucleotide such as a vector
  • Introduction of a polynucleotide, such as a vector, into a host cell can be effected by methods well known to those skilled in the art. Exemplary methods are calcium phosphate transfection, DEAE-Dextran mediated transfection, microinjection, cationic lipid-mediated transfection and electroporation.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is a method for producing the Protoxin-II variant of the invention comprising the steps of providing a host cell of the invention; and culturing the host cell under conditions sufficient for the expression of at least one Protoxin-II variant of the invention.
  • Host cells can be cultured under any conditions suitable for maintaining or propagating a given type of host cell and sufficient for expressing a polypeptide.
  • Culture conditions, media, and related methods sufficient for the expression of polypeptides are well known in the art.
  • many mammalian cell types can be aerobically cultured at 37° C. using appropriately buffered DMEM media while bacterial, yeast and other cell types may be cultured at 37° C. under appropriate atmospheric conditions in LB media.
  • the expression of the Protoxin-II variant can be confirmed using a variety of well-known methods.
  • expression of a polypeptide can be confirmed using detection reagents, such as using SDS-PAGE or HPLC.
  • Another aspect of the invention is a method of modulating the activity of Nav1.7 in a biological tissue, the method comprising contacting the biological tissue expressing Nav1.7 with a Nav1.7-modulating amount of the Protoxin-II variant of the invention.
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be utilized in any therapy where it is desired to treat, reduce or alleviate symptoms of pain or other disorders of sensory or sympathetic neuron dysfunction.
  • Pain treated with the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be any type of pain, such as chronic pain, acute pain, neuropathic pain, nociceptive pain, visceral pain, back pain, pain associated with inflammatory conditions, post-operative pain, thermal pain or pain associated with disease and degeneration.
  • Pain treated with the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be Nav1.7-mediated pain.
  • Nav1.7-mediated pain refers to pain resulting at least partially from increased Nav1.7 channel activity.
  • the methods of the invention may be used to treat an animal patient belonging to any classification.
  • animals include mammals such as humans, rodents, dogs, cats and farm animals.
  • the pain and/or Nav1.7-mediated pain may result from one or more causes, such as peripheral neuropathy, central neuropathy, nerve compression or entrapment syndromes such as carpal tunnel syndrome, tarsus tunnel syndrome, ulnar nerve entrapment, compression radiculopathy, lumbar spinal stenosis, sciatic nerve compression, spinal root compression, intercostal neuralgia, compression radiculopathy and radicular lower back pain, spinal root lesions, neuritis, autoimmune diseases, general inflammation, chronic inflammatory conditions, arthritis, rheumatic diseases, lupus, osteoarthritis, general gastrointestinal disorders, colitis, gastric ulceration, duodenal ulcers, inflammatory bowel disorders, irritable bowel syndrome, pain associated with diarrhea, inflammatory eye disorders, inflammatory or unstable bladder disorders, psoriasis, skin complaints with inflammatory components, sunburn, carditis, dermatitis, myositis, neuritis, collagen vascular diseases, inflammatory pain and associated hyperalgesia and allodyn
  • Protoxin-II variants of the invention include itch, cough and asthma.
  • mice global deletion of the SCN9A gene leads to complete insensitivity to histamine-induced itch (Gingras et al., American Pain Society Meeting Abstract 2013 and U.S. Pat. Publ. No. 2012/0185956).
  • peptide Nav1.7 blockers may have utility in the treatment of itch, which may arise from various sources, such as dermatological or inflammatory disorders; or inflammatory disorders such as renal or hepatobiliary disorders, immunological disorders, medication reactions and unknown/idiopathic conditions, including dermatitis, psoriasis, eczema, insect sting or bite.
  • Nav1.7 is also expressed in sensory nerves innervating the airways (Muroi et al., J Physiol. 2011 Dec. 1; 589(Pt 23):5663-76; Muroi et al., Am J Physiol Regul Integr Comp Physiol. 2013 Apr.
  • peptide Nav1.7 blockers may be beneficial in the treatment of cough e.g., acute or chronic cough, or cough caused by irritation from gastroesophageal reflux disease, and inflammatory diseases of the airways such as asthma and allergy-related immune responses, bronchospasm, chronic obstructive pulmonary disease, chronic bronchitis, emphysema, and hiccups (hiccoughs, singultus).
  • Silencing Nav1.7 in vivo in nodose ganglia of guinea pigs using shRNA nearly abolished the cough reflex induced by mechanical probing (Muroi et al., Am J Physiol Regul Integr Comp Physiol. 2013 Apr 10).
  • One aspect of the invention is a method of alleviating or treating itch, cough or asthma in a subject by administering a therapeutically effective amount of the Protoxin-II variant of the invention disclosed herein, including in the numbered embodiments listed below to a subject in need thereof for a time sufficient to alleviate the itch, cough or asthma.
  • Another aspect of the invention is a method of alleviating or treating Nav1.7-mediated itch, Nav1.7-mediated cough or Nav1.7-mediated asthma in a subject by administering a therapeutically effective amount of the Protoxin-II variant of the invention disclosed herein, including in the numbered embodiments listed below to a subject in need thereof for a time sufficient to alleviate the itch, cough or asthma.
  • Nav1.7-mediated itch refers to itch resulting at least partially from increased Nav1.7 channel activity.
  • Nav1.7-mediated cough refers to cough resulting at least partially from increased Nav1.7 channel activity.
  • Nav1.7-mediated asthma refers to asthma resulting at least partially from increased Nav1.7 channel activity.
  • Protoxin-II variants of the invention disclosed herein may be tested for their effect in reducing or alleviating pain and/or Nav1.7-mediated pain using animal models described herein, and models such as the rat spinal nerve ligation (SNL) model of neuropathic pain, carageenan induced allodynia model, the Freund's complete adjuvant (CFA)-induced allodynia model, the thermal injury model, the formalin model and the Bennett Model, and other models as described in U.S. Pat. Appl. No. 2011/0124711 and U.S. Pat. No. 7,998,980.
  • Carageenan induced allodynia and CFA-induced allodynia are models of inflammatory pain.
  • the Bennett model provides an animal model for chronic pain including post-operative pain, complex regional pain syndrome, and reflex sympathetic dystrophy.
  • any of the foregoing animal models may be used to evaluate the efficacy of Protoxin-II variants of the invention inhibitor in treating pain and/or NAv1.7-mediated pain.
  • the efficacy of the Protoxin-II variants of the invention may be compared to a no treatment or placebo control. Additionally or alternatively, efficacy may be evaluated in comparison to one or more known pain-relieving medicaments.
  • the present invention provides methods of treating Nav1.7-mediated pain using the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below. It has been discovered in the pending application by the inventors (U.S. Patent Application No. 61/781,276) that administration of Nav1.7 blocking peptides are efficacious in treating and/or alleviating pain in various animal models of pain, contrary to what was disclosed and suggested in the literature.
  • peptide inhibitors of Nav1.7 have been shown to be potent and/or selective towards Nav1.7 in in vitro cell culture models using overexpressed Nav1.7 or on isolated neurons in which the blood-nerve barrier is subverted through desheathing or hypertonic saline injection, they have so far proven non-efficacious in in vivo animal models of pain, where the lack of efficacy has been reported to result from the inability of the peptides to pass the blood-nerve barrier.
  • Several publications describe lack of efficacy of Nav1.7 blocking peptides in animal models of pain or in isolated nerves.
  • Nav1.7 is expressed in the peripheral nervous system e.g., in nociceptive dorsal root ganglions (DRG), most notably in nociceptive small-diameter DRG neurons, in particular in peripheral terminals in the skin, with little representation in the brain.
  • DRG nociceptive dorsal root ganglions
  • Nav1.7 distribution e.g. sensory ending
  • physiology predispose it to a major role in transmitting painful stimuli.
  • One embodiment of the invention is a method of treating Nav1.7-mediated pain by administering a therapeutically effective amount of the Protoxin-II variant of the invention disclosed herein, including in the numbered embodiments listed below to a subject in need thereof for a time sufficient to treat the Nav1.7-mediated pain.
  • Protoxin-II variants of the invention disclosed herein may be utilized in any therapy where it is desired to treat Nav1.7-mediated pain or other disorders of sensory or sympathetic neuron dysfunction. “Treat” or “treatment” of pain is meant to include partially or completely to prevent, stop, inhibit, reduce, or delay the perception of pain.
  • the Nav1.7-mediated pain is chronic pain, acute pain, neuropathic pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis, or pain associated with disease and degeneration.
  • PE primary erythemalgia
  • PEPD paroxysmal extreme pain disorder
  • osteoarthritis osteoarthritis
  • rheumatoid arthritis lumbar discectomy
  • pancreatitis fibromyalgia
  • painful diabetic neuropathy (PDN) post-herpetic neuropathy (PHN)
  • TN trige
  • Neuropathic pain includes for example painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN) or trigeminal neuralgia (TN).
  • PDN painful diabetic neuropathy
  • PPN post-herpetic neuropathy
  • TN trigeminal neuralgia
  • Other causes of neuropathic pain include spinal cord injuries, multiple sclerosis, phantom limb pain, post-stroke pain and HIV-associated pain.
  • Conditions such as chronic back pain, osteoarthritis and cancer may also result in the generation of neuropathic-related pain and thus are potentially suitable for treatment with the Protoxin-II variants of the invention.
  • the Nav1.7-mediated pain is associated with primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis or fibromyalgia.
  • PE primary erythemalgia
  • PEPD paroxysmal extreme pain disorder
  • osteoarthritis rheumatoid arthritis
  • lumbar discectomy pancreatitis or fibromyalgia.
  • the Protoxin-II variants of the invention may be conjugated to a second polypeptide to form a fusion protein.
  • fusion proteins are for example the well-known Fc fusions or fusions to human serum albumin to extend half-life of the peptide inhibitors.
  • the conjugation may be a direct conjugation via a linker, such as a glycine-serine rich linker.
  • linkers are well known in the art.
  • the Protoxin-II variants of the invention incorporating additional moieties may be compared for their Nav1.7 blocking ability and efficacy in treatment or reducing pain using well known methods and those described herein.
  • Protoxin-II variants of the invention include asthma, cough, heartburn, itch, dermatitis, bladder instability, and Reynaud's disease.
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be formulated in a pharmaceutically acceptable vehicle or carrier.
  • One embodiment of the invention is a pharmaceutical composition comprising the isolated Protoxin-II variant of the invention and a pharmaceutically acceptable excipient.
  • a suitable vehicle or carrier may be water for injection, physiological saline solution or artificial cerebrospinal fluid, possibly supplemented with other materials common in compositions for parenteral administration.
  • Neutral buffered saline or saline mixed with serum albumin are further exemplary vehicles.
  • These solutions are sterile and generally free of particulate matter, and may be sterilized by conventional, well-known sterilization techniques (e.g., filtration).
  • the compositions may contain pharmaceutically acceptable excipients as required to approximate physiological conditions, such as pH adjusting and buffering agents, stabilizing, thickening, lubricating and coloring agents, etc.
  • Suitable vehicles and their formulation and packaging are described, for example, in Remington: The Science and Practice of Pharmacy (21st ed., Troy, D. ed., Lippincott Williams & Wilkins, Baltimore, Md. (2005) Chapters 40 and 41).
  • Protoxin-II variants of the invention may be administered by peripheral administration.
  • Peripheral administration or “administered peripherally” means introducing an agent into a subject outside of the central nervous system.
  • Peripheral administration encompasses any route of administration other than direct administration to the spine or brain.
  • Peripheral administration can be local or systemic. Local administration may be used to concentrate the therapeutic to the site of action, such as local administration to joints, surgical wounds, sites of injury/trauma, peripheral nerve fibers, various organs (GI, urogenital, etc.) or inflamed tissues.
  • Systemic administration results in delivery of a pharmaceutical composition to essentially the entire peripheral nervous system of the subject and may also result in delivery to the central nervous system depending on the properties of the composition.
  • Routes of peripheral administration encompass, without limitation, topical administration, intravenous, subcutaneous, intra-muscular, intra-articular or other injection, and implanted mini-pumps or other extended release devices or formulations.
  • Compounds may also be administered directly to the central nervous system e.g., intrathecal or intracisternal administration. Continuous intrathecal administration can be achieved via the use of implanted spinal drug pumps.
  • compositions of the invention include formulations involving the Protoxin-II variants of the invention in sustained- or controlled-delivery formulations. These formulations may be achieved through use of for example injectable microspheres, bio-erodible particles, microemulsions, nanoparticles, nanocapsules, macroemulsions, polymeric compounds (such as polyesters, polyamino acids, hydrogels, poly(lactic acid), polyglycolic acid or ethylene vinylacetate copolymers), beads or liposomes, hyaluronic acid or implantable drug delivery devices.
  • injectable microspheres such as polyesters, polyamino acids, hydrogels, poly(lactic acid), polyglycolic acid or ethylene vinylacetate copolymers
  • beads or liposomes such as hyaluronic acid or implantable drug delivery devices.
  • Protoxin-II variants of the invention disclosed herein may be prepared for use for parenteral (subcutaneous, intramuscular or intravenous), intracerebral (intraparenchymal), intrathecal, intra-articular, intracerebroventricular, intramuscular, intra-ocular, intra-arterial, intraportal, or intralesional routes; by sustained release systems or by implantation devices, or any other administration, particularly in the form of liquid solutions or suspensions; for buccal or sublingual administration such as in the form of tablets or capsules; or intranasally such as in form of powders, nasal drops or aerosols or certain agents; transdermally in a form of a gel, ointment, lotion, cream or dusting powder, suspension or patch delivery system with chemical enhancers to either modify the skin structure or to increase the drug concentration in the transdermal patch, or with agents that enable the application of formulations containing proteins and peptides onto the skin (Int.
  • composition also may be administered locally via implantation of a membrane, sponge or another appropriate material onto which the desired molecule has been absorbed or encapsulated.
  • the device may be implanted into any suitable tissue or organ, and delivery of the desired molecule may be via diffusion, timed-release bolus, or continuous administration.
  • the concentration of the Protoxin-II variants of the invention or other peptide inhibitors of Nav1.7 in such pharmaceutical formulation can vary widely, for example from about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2% or between 2% to 5%, up to as much as 15%, 20%, 30%, 40%, 50%, 60% or 70% by weight and will be selected primarily based on fluid volumes, viscosities and other factors, according to the particular mode of administration selected.
  • the Protoxin-II variants of the invention can be lyophilized for storage and reconstituted in a suitable vehicle prior to use. This technique has been shown to be effective with conventional protein preparations. Lyophilization and reconstitution techniques are well known in the art.
  • An exemplary pharmaceutical composition of the present invention may comprise Tris buffer of about pH 7.0-8.5, or acetate buffer of about pH 4.0-5.5, and may further include sorbitol, sucrose, Tween-20 and/or a suitable substitute thereof.
  • a therapeutically effective amount refers to an amount or dosage sufficient to produce a desired result, i.e. to partially or completely prevent, stop, inhibit, reduce, or delay the perception of pain associated with any painful medical condition.
  • the therapeutically effective amount may vary depending on the specific vehicle and the Protoxin-II variants of the invention selected, and is also dependent on a variety of factors and conditions related to the subject to be treated and the severity of the pain. For example, factors such as age, weight and health of the subject to be administered with the pharmaceutical compositions of the invention as well as dose response curves and toxicity data obtained in preclinical animal work could be among those considered.
  • a determined dose may, if necessary, be repeated at appropriate time intervals selected as appropriate by a physician or other person skilled in the relevant art (e.g. nurse, veterinarian, or veterinary technician) during the treatment period.
  • a physician or other person skilled in the relevant art e.g. nurse, veterinarian, or veterinary technician
  • the determination of an effective amount or a therapeutically effective amount for a given agent is well within the ability of those skilled in the art.
  • a pharmaceutical composition of the invention for intramuscular injection could be prepared to contain 1 ml sterile buffered water, and between about 1 ng to about 100 mg, about 50 ng to about 30 mg or about 5 mg to about 25 mg of a Protoxin-II variant of the invention.
  • a pharmaceutical composition of the invention for intravenous infusion could be made up to contain about 250 ml of sterile Ringer's solution, and about 1 mg to about 30 mg or about 5 mg to about 25 mg of the Protoxin-II variants of the invention.
  • Actual methods for preparing parenterally administrable compositions are well known and are described in more detail in, for example, “Remington's Pharmaceutical Science”, 15th ed., Mack Publishing Company, Easton, Pa.
  • X 1 is G, P, A or deleted
  • X 2 is P, A or deleted
  • X 3 is S, Q, A, R or Y;
  • X 4 is Q, R, K, A or S;
  • X 5 is K, S, Q or R;
  • X 6 is M or F
  • X 7 is T, S, R, K or Q
  • X 8 is D or T
  • X 9 is S, A or R;
  • X 10 is E, R, N, K, T or Q;
  • X 11 is R or K
  • X 12 is K, Q, S or A
  • X 13 is E, Q or D
  • X 14 is G or Q
  • X 15 is V or S
  • X 16 is R or T
  • X 17 is K or R
  • polypeptide inhibits human Nav1.7 activity with an IC 50 value of about 1 ⁇ 10 ⁇ 7 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • FRET fluorescence resonance energy transfer
  • the Protoxin-II variant of claim 1 wherein the N-terminal extension comprises the amino acid sequence of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
  • the Protoxin-II variant of claim 1 or 2 wherein the C-terminal extension comprises the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
  • X 1 is Q, R, K, A, or S;
  • X 2 is K, S, Q or R;
  • X 3 is M or F
  • X 4 is T, S, R, K or Q
  • X 5 is D or T
  • X 6 is S, A or R;
  • X 7 is E, R, N, K, T or Q;
  • X 8 is R or K
  • X 9 is K, Q, S or A
  • X 10 is E, Q or D
  • X 11 is G or Q
  • X 12 is V or S
  • X 13 is R or T
  • X 14 is K or R.
  • the isolated Protoxin-II variant of claim 9 comprising the amino acid sequence of SEQ ID NOs: 56, 78, 111, 114, 117, 118, 119, 122, 123, 129, 130, 131, 132, 133, 134, 135, 136, 138, 139, 140, 141, 142, 145, 146, 147, 149, 150, 151, 152, 153, 154, 16, 158, 159, 165, 172, 173, 175, 177, 178, 183, 184, 185, 186, 189, 190, 193, 197, 199, 207, 210, 211, 216, 217, 224, 266, 273, 282 or 335.
  • X 1 is Y, Q, A, S or R;
  • X 2 is T or S
  • X 3 is S, R or A
  • X 4 is E, T or N;
  • X 5 is E or Q
  • X 6 is V or S
  • X 7 is R or T
  • X 8 is K or R.
  • the isolated Protoxin-II variant of claim 12 comprising the amino acid sequence of SEQ ID NOs: 56, 59, 65, 78, 111, 114, 117, 118, 119, 121, 122, 123, 129, 130, 133, 150, 190, 217, 281, 324, 325 or 326.
  • X 1 is T or S
  • X 2 is S, R or A
  • X 3 is E, T or N;
  • X 4 is E or Q
  • X 5 is V or S
  • X 6 is R or T
  • X 7 is K or R.
  • Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 78 (GPQCQKWMQTCDRERKCCEGFVCTLWCRKKLW-COOH), wherein
  • amino acid sequence has Q at position 1, Q at position 7 and F at position 19, when residue numbering is according to SEQ ID NO: 1;
  • the polypeptide inhibits human Nav1.7 activity with an IC 50 value of about 30 ⁇ 10 ⁇ 9 M or less, wherein the IC 50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25 ⁇ 10 ⁇ 6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7; and
  • FRET fluorescence resonance energy transfer
  • the fusion protein of claim 17 wherein the half-life extending moiety is human serum albumin (HSA), albumin binding domain (ABD), Fc or polyethylene glycol (PEG).
  • HSA human serum albumin
  • ABS albumin binding domain
  • Fc polyethylene glycol
  • a vector comprising the isolated polynucleotide of claim 19 .
  • a host cell comprising the vector of claim 20 .
  • a method of producing the isolated Protoxin-II variant comprising culturing the host cell of claim 21 and recovering the Protoxin-II variant produced by the host cell.
  • a pharmaceutical composition comprising the isolated Protoxin-II variant of claim 1 , 6 , 12 , 13 or 15 and a pharmaceutically acceptable excipient.
  • a method of treating Nav1.7-mediated pain in a subject comprising administering to a subject in need thereof an effective amount of the Protoxin-II variant of any of the claims 1 - 16 to treat the pain.
  • pain is chronic pain, acute pain, neuropathic pain, cancer pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis.
  • PE primary erythemalgia
  • PEPD paroxysmal extreme pain disorder
  • osteoarthritis osteoarthritis
  • rheumatoid arthritis rheumatoid arthritis
  • lumbar discectomy pancreatitis
  • fibromyalgia painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia
  • Protoxin-II variant for use according to claim 29 , wherein pain is chronic pain, acute pain, neuropathic pain, cancer pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis.
  • PE primary erythemalgia
  • PEPD paroxysmal extreme pain disorder
  • osteoarthritis osteoarthritis
  • rheumatoid arthritis lumbar discectomy
  • pancreatitis fibromyalgia
  • PPN post-herpetic neuropathy
  • Protoxin-II variant for use according to claim 29 , 30 or 31 , wherein the Protoxin-II variant is administered locally to a joint, spinal cord, surgical wound, sites of injury or trauma, peripheral nerve fibers, urogenital organs, or inflamed tissues.
  • a Protoxin-II single position limited amino acid substitution scanning library was designed to assess to what degree selectivity, peptide yield, and homogeneity can be improved.
  • Protoxin-II variants were designed as HRV3C protease cleavable HSA fusion proteins in the following format from N- to C-terminus: 6 ⁇ His-HSA-linker-HRV3C cleavable peptide Protoxin-II variant (“6 ⁇ His” disclosed as SEQ ID NO: 108); linker being (GGGGSGGGGSGGGGSGGGGS; SEQ ID NO: 80, HSA having the sequence of SEQ ID NO: 106, HRV3C cleavable peptide having the sequence of SEQ ID NO: 82). Each Protoxin-II variant, after cleavage from HSA had a residual N-terminal GP from the cleavage site.
  • the variants were characterized in membrane depolarization assays using FLIPR® Tetra as described in Example 3 veratridine-induced depolarization inhibition assay, and in whole cell patch clamp experiments using the QPatch assay as described in Example 3.
  • Combinatorial libraries were designed to test for additive effects of select single position hits in an attempt to generate Nav1.7 antagonists with further improved potency and selectivity profile compared to the native peptide.
  • the designed Protoxin-II variant genes were generated using synthetic gene assembly technology as described in U.S. Pat. No. 6,521,427.
  • the amino acid sequences of the designed peptide variants were back-translated to DNA sequences using human high-frequency codons.
  • the DNA sequence of each variant gene, together with a portion of vector DNA including the DNA cloning sites, was synthesized as multiple oligonucleotides, some of which contained degenerate codons, and assembled into full-length DNA fragments.
  • the assembled DNA fragments were amplified by PCR and PCR products were subsequently cloned as a pool.
  • HEK 293-F cells were maintained in 293 FreestyleTM media (Invitrogen Cat#12338) and split when the cell concentration was between 1.5 and 2.0 ⁇ 10 6 cells per ml. The cells were grown in suspension, shaking at 125 RPM in a humidified incubator set at 37° C. and 8% CO 2 . HEK 293F cells were transiently transfected using a DNA/lipid complex after they were diluted to 1.0 ⁇ 10 6 cells per ml.
  • the supernatant was separated from the cells by centrifugation at 5,000 ⁇ g for 10 minutes and filtered through a 0.2 ⁇ m filter (Corning; Cat#431153), then concentrated 10 and 50 fold using an Amicon Ultra Concentrator 10K (Cat#UFC901096), and centrifuging for approximately 10 minutes at 3,750 ⁇ g.
  • Protoxin-II variants were expressed as HSA fusion proteins as indicated in Example 1 and the Protoxin-II variant peptides were cleaved with HRV3C protease prior to purification. Two methodologies were tested for efficient purification of the Protoxin-II variants.
  • the secreted proteins were purified from the expression supernatants via IMAC using 1 ml HisTrap HP columns (GE Healthcare Cat#17-5247-01).
  • the chromatography method was run using an AKTA Xpress and protein was eluted from the column using a step gradient of imidazole. Peak fractions were pooled and digested overnight with HRV 3C protease (1 ⁇ g protease/150 ⁇ g fusion).
  • Cleaved peptide-fusion pools were further purified using a Dionex HPLC system with a reverse phase Phenomenex Luna 5 pm C18(2) column (Cat#00B-4252-PO-AX). Samples were eluted from the column with a 0-68% acetonitrile (0.05% TFA) linear gradient. Elution fractions were pooled, lyophilized overnight and reconstituted in HEPES buffered saline, pH 7.4 (10 mM HEPES, 137 mM NaCl, 5.4 mM KCl, 5 mM glucose, 2 mM CaCl 2 , 1 mM MgCl 2 ).
  • Table 4 shows yields of Protoxin-II variants purified by RP-HPLC. The average mg yield/L was 0.01615.
  • the secreted proteins were purified from the expression supernatants via IMAC using 1 mL HisTrap HP columns (GE Healthcare Cat#17-5247-01).
  • the chromatography method was run using an AKTA Xpress and protein was eluted from the column using a step gradient of Imidazole. Peak fractions were pooled and digested overnight with HRV3C protease (1 ⁇ g protease/150 ⁇ g fusion).
  • the cleaved sample was loaded into a 50 kDa molecular weight cutoff centrifugal filter unit (Millipore UFC805096) and cleaved peptide collected in the filtrate fraction.
  • Peptide pools were loaded onto a 96-well solid phase extraction block (Agilent Bond Elut Plexa A3969030) for further purification, desalting, and concentration. Blocks were used in conjunction with a vacuum manifold (Whatman). Peptide samples were loaded and washed in 0.05% TFA in water and eluted with a step gradient of acetonitrile with 0.05% TFA in water. Elution fractions were then lyophilized overnight and reconstituted in HEPES buffered saline, pH 7.4 (10 mM HEPES, 137 mM NaCl, 5.4 mM KCl, 5 mM glucose, 2 mM CaCl 2 , 1 mM MgCl 2 )
  • Peptides were reconstituted in supplemented HEPES buffered saline, pH 7.4 (10 mM HEPES, 137 mM NaCl, 5.4 mM KCl, 5 mM glucose, 2 mM CaCl 2 , 1 mM MgCl 2 ) and absorbance was measured at 280 nm. Concentration values were then calculated using each sample's extinction coefficient. 2 ⁇ g of each peptide were loaded onto an Invitrogen NuPAGE® Novex® Bis-Tris Gel 15 well gel and run in MES buffer non-reduced.
  • Table 5 shows yields (mg) of Protoxin-II variants purified by SPE. The average mg yield/L was 0.05353.
  • the ability of the generated peptides to inhibit membrane depolarization induced by the Nav1.7 agonist veratridine (3-Veratroylveracevine; Biomol, Catalog#NA125) was measured with a veratridine-induced depolarization inhibition assay measuring decline in FRET (fluorescence resonance energy transfer) assay on a fluorescent resonance image plate reader (FLIPR® Tetra; Molecular Devices) using DISBAC2(3) (Invitrogen, K1018) as an electron acceptor and PTS18 (Trisodium 8-octadecyloxypyrene-1,3,6-trisulfonate) (Sigma) as a donor by exciting the donor at 390-420 nm and measuring FRET at 515-575 nm.
  • FRET fluorescence resonance energy transfer
  • FLIPR® Tetra fluorescent resonance image plate reader
  • PTS18 Trisodium 8-octadecyloxypyrene-1,3,6-trisulfonate
  • HEK293 cells stably expressing human Nav1.7 were cultured in DMEM/F-12 media (1:1), supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, 400 ⁇ g/mL geneticin and 100 ⁇ M NEAAs (all reagents from Invitrogen). 50 ⁇ L of harvested cells were plated at 25,000 cells/well into poly-lysine coated 384-well black clear bottom plates. The plates were incubated at room temperature (RT) for 15 min followed by an overnight incubation at 37° C. All incubations were done in the dark unless otherwise stated.
  • RT room temperature
  • Peptides were suspended at 3 ⁇ their final concentration in the assay buffer containing 10 ⁇ M DISBAC2(3) and 400 ⁇ M VABSC-1 to suppress background fluorescence (Sigma, cat#201987). 25 ⁇ L/well of the suspended peptides were added into each well, and incubated for 60 minutes at RT. Depolarization was induced by 25 ⁇ M final concentration of veratridine (by adding 25 ⁇ L/well of 75 ⁇ M (3 ⁇ ) stock solution), and the reduction in the mean intensity of FRET dye fluorescence was measured 30-100 seconds after adding the agonist. A 1.3 ⁇ dilution of each measured peptide occurred after adding veratridine by convention, the concentration at the beginning of the veratridine-induced depolarization inhibition assay is reported.
  • Concentration-response curves of synthetic Protoxin-II were constructed in each experimental series and were used as controls. Fluorescence counts for each well were converted to % response by normalizing the signal to the difference between negative control (response to agonist veratridine alone) and positive control (response to veratridine in the presence of 10 ⁇ M tetracaine) values. For measurements, “spatial uniformity correction” (all fluorescence traces are normalized to the average initial starting intensity) and “subtract bias value” (subtract the initial starting intensity from each trace) were turned on in FLIPR® Tetra. Each data point represented the response in an individual well.
  • HEK293 cells stably expressing human Nav1.5 (SEQ ID NO: 105), Nav1.7 (SEQ ID NO: 79) or Nav1.6 (SEQ ID NO: 407) were cultured in DMEM/F-12 media (1:1), supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, 400 ⁇ g/mL Geneticin and 100 ⁇ M NEAAs (all reagents from Invitrogen). Cells were maintained at 37° C. and in 5% CO 2 and assayed upon reaching ⁇ 50-90% confluency.
  • CHO cells stably expressing human Nav1.6 in a tetracycline-inducible manner (SEQ ID NO: 407) were cultured in HAMs F12, supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, 10 ⁇ g/mL Blasticidin and 400 ⁇ g/mL Zeocin. Cells were maintained at 37° C. and in 5% CO 2 , and assayed upon reaching ⁇ 50-90% confluency.
  • Nav1.6 expression was induced with 1 ⁇ g/ml of tetracycline, 24-48 h prior to an experiment.
  • the voltage protocol used in the assay was as follows.
  • the first liquid application contained only the control buffer (5 ⁇ L).
  • the voltage protocol was executed 10 times (for a total duration of 10 min) five sec after the application.
  • the next three liquid applications (5 ⁇ L each) contained a test compound (same compound at the same concentration for all three applications) or control buffer (for control cells only). Five seconds after each of these applications, the voltage protocol was again executed 10 times (also once per min).
  • the last application contained positive (composed of three 10 ⁇ L sub-applications, each separated by 2 sec), five seconds after which the same voltage protocol was executed twice to obtain the baseline current. Currents were sampled at 25 kHz and filtered at 5 kHz with an 8-pole Bessel filter. The series resistance compensation level was set at 80%.
  • the peak current amplitude at 0 mV for each current trace in the first four liquid applications was first subtracted from that of the last trace in the presence of positive control and then normalized to that of the last trace in the first (control buffer) application as % inhibition.
  • this (% inhibition) value for each cell in the presence of a test compound was further normalized to the average % inhibition value for control (typically 5-6) cells in the same experiment.
  • the mean of the last two such values in the last compound application i.e., the corrected % inhibition value for each concentration of a test compound
  • the % inhibition values for all cells tested at each compound concentration were averaged and used in concentration response calculations.
  • Combinatorial libraries were designed to test for additive effects of select single position hits in an attempt to generate Nav1.7 antagonists with further improved potency and selectivity profile compared to the native peptide using several approaches.
  • Protoxin-II/Huwentoxin-IV single position chimeras were designed bidirectionally. The purpose of this library was to obtain Protoxin-II variants that retained potency and selectivity profile of the wild type Protoxin-II and would achieve beneficial refolding properties associated with Huwentoxin-IV. Substitutions R22T and E12N were identified from this scan.
  • Peptide NV1G1153 was further engineered by diversifying position Y1 by a limited amino acid scan using R, K, T, A, D, E, Q and S, and by charge cluster engineering, where all sets of charged residues in the three-dimensional structure of the peptide (D10/E12, K4/E17, D10/E12/R13) were mutated.
  • N- and C-terminal extensions were introduced to select peptides, including NV1G1153 with the purpose of improving peptide distribution to the site of action and of improving half-life of the peptides without significantly increasing the molecular weight of the resulting peptide.
  • the N- and C-terminal extensions that were used are shown in Table 8 and 9, respectively, and are described in Oi et. al., Neuroscience Letters 434, 266-272, 2008; Whitney et. al., Nature Biotechnology 2011 29:4, 352-356; Sockolosky et. al., (2012) 109:40, 16095-16100.
  • Cell penetrating peptides HIV Tat and polyarginine were also used.
  • Various linkers were used to couple the Protoxin-II variant to the N- and/or C-terminal extensions. The linkers used are shown in Table 10.
  • Protoxin-II variants from each campaign were tested for their potency and selectivity for Nav1.7 using methods described in Example 3.
  • the amino acid sequences of the variants that inhibited Nav1.7 with an IC 50 value of 200 nM or less are shown in Table 3.
  • Table 11 shows the amino acid substitutions in select variant when compared to the wild type Protoxin-II, and the IC 50 values for Nav1.7 inhibition in the veratridine-induced depolarization inhibition assay.
  • FIG. 1 shows the sequence genus of generated Protoxin-II variants that inhibit Nav1.7 with an IC 50 value of 30 nM or less.
  • the amino acid sequences of the peptides shown in FIG. 2 are shown in FIG. 3 . All these peptides had W7Q and M19F substitutions when compared to the wild type Protoxin-II.
  • the Protoxin-II variants were expressed and purified as described in Example 1, or synthesized by standard solid phase synthesis methods. The yields of the recombinant or synthetic peptides were compared to the yields of the wild-type Protoxin-II. Table 12 shows that the yields of the select Protoxin-II variants were significantly higher than that of Protoxin-II, indicating improved folding properties of the variants. The scale of the solid-phase synthesis was 0.5 mmol.
  • mice Male C5761/6 mice (24-26 g), ordered from Charles River and housed individually, were used for this study.
  • Von Frey Test Mechanical (tactile) threshold was assessed by Von Frey Hairs following the Up-Down method (Dixon, 1980, Chaplan et al., 1994). 7 graded stimuli (von Frey filaments: 0.03, 0.07, 0.16, 0.4, 0.6, 1, 2 g; Stoelting, Wood Dale, IL) were used. Von Frey hairs were presented perpendicularly against the center plantar area (between toris) on a hindpaw. Sufficient force was applied to bend the filament slightly and held for 3 seconds. Per the Chaplan paper, a positive response can be either 1) a sharp withdrawal or 2) immediate flinching upon removal of the filament. See Chaplan et al for more details. Mice were acclimated to the wire mesh in the testing chamber for 30-60 minutes prior to testing.
  • Hargreaves Test A modified Hargreaves box was used to measure thermal paw withdrawal latency (PWL) (Hargreaves et al., 1988, Pain, 32:77-88; Dirig et al.,1997, J Neurosci. Methods, 76:183-191).
  • This box consists of a chamber with a raised glass floor maintained at a constant temperature (27° C.).
  • the thermal nociceptive stimulus originates from a projection bulb light beam below the glass surface. The light beam is aimed at the area between toris (center plantar).
  • the “start” button will turn on the light and start the timer. Movements (such as a sudden withdrawal) of the stimulated paw will trigger the switch to turn off the light and stop the timer.
  • the latency in seconds is displayed.
  • the bulb will be turned off after 20 seconds (cutoff) to prevent tissue injury.
  • the animals were allowed to habituate on the glass surface for 30-60 minutes before PWL measurement. Constant amperage was used throughout the study, which resulted in Pre-test paw withdrawal latencies between 8-12 seconds when averaged over 3 to 6 read-outs taken at least 5 minutes apart.
  • T 0 threshold on day 0 (post-CFA, pre-pump); threshold on day I post pump implantation; Tc: cut-off of the test (20 s for the Hargreaves test and 2 g for the Von Frey test).
  • Hotplate Test Animals were placed on a 10′′ ⁇ 10′′ metal plate surrounded by 4 Plexiglas walls (15 inches high). The plate was maintained at a temperature of either 50 or 55° C. The response latency (time when the animal first flinches or licks its hind paw, jumps, or vocalizes) was measured and the animal removed from the plate. Animals showing no response were removed from the plate after 40 s (50° C.) or 20 s (55° C.) to prevent any possible tissue damage. This trial was repeated 2-5 times every 15-60 minutes in a day.
  • CFA Model Animals were anesthetized with isoflurane (4% induction and 2% maintenance) and 20 ⁇ L of 100% Complete Freund's Adjuvant (CFA; Sigma-Aldrich; Saint Louis, Mo.) was injected into the center plantar area on one hind paw using a 27 gauge needle attached to a 50 ⁇ L Hamilton syringe.
  • CFA Complete Freund's Adjuvant
  • Carrageenan model Animals were anesthetized with isoflurane (4% induction and 2% maintenance) and 25 ⁇ L of 2% Acarrageenan (Sigma-Aldrich; Saint Louis, Mo.) dissolved in normal saline was injected into the center plantar area on hind paws using an insulin syringe (BD; Franklin Lakes, N.J.).
  • Acarrageenan Sigma-Aldrich; Saint Louis, Mo.
  • Alzet micro-osmotic mini pumps (Durect Corporation Model 1003D and 2001D) were filled and primed per manufacturer's guide. Mice were anesthetized with isoflurane (5% induction; 2% maintenance). Their backs were shaved, wiped down with isopropyl alcohol and povidone iodine, and a small incision was made between the scapulae. Using a pair of forceps or hemostat, a small pocket was formed by spreading the subcutaneous connective tissues apart. The pump was inserted into the pocket with the flow moderator pointing away from the incision. The skin incision was then closed using 7 mm staples and the animals were allowed to recover in their home cages.
  • NV1D3034-OH NV1D3034-COOH
  • NV1D3368-OH NV1D3368-COOH
  • NV1D2775-OH NV1D2775-COOH
  • NV1D3368-OH fully reversed CFA-induced thermal hyperalgesia at 684 and 1824 ⁇ g/day ( FIGS. 5A and 5B ).
  • NV1D2775-OH demonstrated strong efficacy in the CFA model. Thermal latencies reached values close to the cut-off following NV1D2775 administration ( FIGS. 6A and 6B , 1824 ⁇ g/day), suggesting a strong analgesia effect on top of the anti-hyperalgesia effect.
  • NV1D2775-OH reversed CFA-induced tactile allodynia ( FIGS. 6C and 6D , 1824 ⁇ g/day).
  • NV1D2775-OH The anti-hyperalgesic effect of NV1D2775-OH was seen as early as 4 hr post-pump implantation ( FIG. 7A ). The effect reached the maximum at 8 hr in both the thermal and tactile tests ( FIGS. 7A and 7B ), which was maintained at 24 hr. Thermal latency and tactile threshold returned to the control level by 48 h post pump implantation (approximately 24 h after the pumps were predicted to be empty) ( FIGS. 7A and 7B ).
  • NV1D2775-OH also exhibited strong, dose-dependent efficacy in the hotplate test ( FIG. 8 ). Latencies at 50 and 55° C. reached values near cut-off following the administration of 1824 ⁇ g/day. At 228 ⁇ g/day, NV1D2775-OH produced a modest yet significant increase in the thermal latency, compared to the PBS control.
  • NV1D2775-OH was evaluated in another model of inflammatory pain, the carrageenan model.
  • Animals were implanted with NV1D2775-OH or PBS pumps. Thermal withdrawal latencies were measured pre-and on day I post-pump. A-carrageenan was injected into the hindpaws and thermal latencies were measured again on 2, 3 and 4 hr following carrageenan.
  • NV1D2775-OH at 1824 ⁇ g/day produced significant analgesia ( FIG. 9 ). Injection of A-carrageenan in the hindpaws induced inflammation (not shown) and lowered thermal paw withdrawal latency in the Hargreaves test over the 4 hr test-period ( FIG. 9 , PBS group). Animals pretreated with NV1D2775-OH at 1824 ⁇ g/day were fully protected from carrageenan-induced hyperalgesia.
  • Mutant peptides were expressed as recombinant fusions to human serum albumin and site-specifically enzymatically cleaved using HRV3C to generate Protoxin-II variants as described in Example 1.
  • Each Protoxin-II variant after cleavage from HSA had a residual N-terminal GP from the cleavage site.
  • IC50 values against human Nav1.7 were measured using veratridine-induced depolarization inhibition assay or Qpatch according to the protocols described in Example 3.
  • Variants demonstrating IC 50 ⁇ 100 nM for human Nav1.7 were counter-screened for selectivity against additional hNav channels using Qpatch electrophysiology. Selective hits were identified and used in the design of combinatorial peptide libraries which were produced using both recombinant expression and solid-phase peptide synthesis. Combinatorial variants were screened using the same strategy as detailed above.
  • positions that can be mutated to improve selectivity include Gln3, Ser11, Glu12, Lys14, Glu17, Gly18, Leu29 and Trp30 (residues numbering according to SEQ ID NO: 1).
  • the solution structure of Protoxin-II was determined by NMR and is shown in FIG. 10 as a surface representation.
  • the left hand side of the Figure shows the previously described (Park et al., J. Med. Chem. 2014, 57:6623-6631) ring of Trp residues, W5/W7/W24, surrounding M6.
  • a selectivity face was identified in this study on Protoxin-II consisting of multiple amino acid positions which can be mutated to improve selectivity for hNav1.7 over other sodium channel isoforms.
  • the residues residing on the selectivity face include residues Ser11, Glu12, Lys14, Glu17, Gly18, Leu29 and Trp30 (residue numbering according to SEQ ID NO: 1).
  • the identification of the selectivity face and multiple positions within responsible for selectivity towards Nav1.7 has not been described earlier.
  • a key step in the synthetic production of Protoxin-II variants is the oxidative refolding of the linear peptide, where the disulfide pairings are formed.
  • the RP-HPLC trace for native Protoxin-II purification following refolding revealed multiple peaks at differing retention times that were of correct mass but demonstrated differing levels of activity, indicative of a mixture of properly and improperly folded isomers of the peptide.
  • the relative abundance of the RP-HPLC major peak, and therefore the relative abundance of correctly folded peptide could be improved by making substitutions at various Protoxin-II positions. Mutation of Trp7 or Trp30 improved folding of the resulting Protoxin-II variant. Mutation of both Trp7 and Trp30 in combination further improved folding of the resulting Protoxin-II variant, and could rescue folding of difficult-to-refold Protoxin-II variants.
  • Protoxin-II belongs to a family 3 of inhibitory cysteine knot peptides (Klint et. al., Toxicon 60:478-491, 2012).
  • Trp7 is conserved in all family 3 members, and substitutions at this position as well as at Trp5 and Met6 in Jingzhaotoxin-V, another family 3 inhibitory cysteine knot peptide, resulted in loss in potency, indicating that hydrophobic residues at positions 5, 6 and 7 in Jingzhaotoxin-V are essential to Jingzhaotoxin-V Nav1.7 inhibitory potency (Int. Pat. Publ. No. 2014/165277). Trp5/Met6/Trp7 is also conserved in Protoxin-II, and therefore it was unexpected that polar substitutions at Trp7 can be made without loss of Protoxin-II activity with significantly improved refolding properties. Substitutions at Trp30 were shown to simultaneously improve Nav1.7 selectivity and refolding properties of the variant peptide and were unexpected since individual advantageous substitutions typically only improve a single parameter.
  • Table 14 shows the amino acid sequences of the select generated Protoxin-II variants.
  • Protoxin-II variants were expressed and purified as described in Example 1, or synthesized by standard solid phase synthesis methods. The yields of the recombinant or synthetic peptides were compared to the yields of the wild-type Protoxin-II. Table 17 shows that the yields of the select Protoxin-II variants were significantly higher than that of Protoxin-II, indicating improved folding properties of the variants. The scale of the solid-phase synthesis was 0.1 mmol.
  • Protoxin-II Variants are Efficacious in In Vivo Models of Pain Following Intrathecal Administration
  • Efficacy of select Protoxin-II variants in reducing pain after intrathecal administration was evaluated.
  • Peptides NV1D2775-OH, NV1D3034 and 63955918 were used in the studies. Animal models that measure acute thermal pain (tail flick and hot plate) and injury-induced pain (formalin flinching) were used.
  • Tail-flick test The animals were placed on a tail-flick device (Ugo Basile). The device has a focal infrared light heating area (diameter-5 mm). The tail (1 ⁇ 3-1 ⁇ 2 way from distal end) of the animal was placed on the focal heating area. The temperature of the heat source was adjusted to elicit a tail-flick within 10 seconds in animals treated with vehicle. A 15 second cut-off time was used to prevent tissue damage, as is standard in the literature. The time elapsed between the start of the heat stimulus and any avoidance response was measured automatically and recorded for the test groups.
  • Hot plate test Animals were placed on a 10′′ ⁇ 10′′ metal plate surrounded by 4 Plexiglas walls (15 inches high). The plate was maintained at a temperature of 52.5° C. The response latency (time when the animal first flinches or licks its hind paw, jumps, or vocalizes) was measured and the animal removed from the plate. Animals showing no response were removed from the plate after 30 s to prevent any possible tissue damage.
  • Formalin Flinching Formalin-induced pain behavior (i.e. paw flinches) was measured using an automated “flinch response” measuring device manufactured by UCSD. The device detects any sudden movement of a metal band glued onto one hind paw of the animal using a motion sensor installed underneath the device floor. One-half to one hour prior to formalin injection, a small metal band was attached to the plantar surface of one hind paw using a small drop of cyanoacrylate and the animal was placed in the testing chamber to be acclimatized. Formalin (2.5%, 50 ⁇ L) was injected subcutaneously into the dorsum of the paw with the metal band. The animal was placed in the customized cylinder (25 ⁇ 10 ⁇ 20 cm, San Diego Instrument) immediately after intraplantar formalin injection. Paw flinches were recorded automatically.
  • Protoxin-II variant 63955918 produced potent and prolonged analgesia as indicated by the elevated latency in the tail flick test ( FIG. 11A and FIG. 11B ) and hot plate test ( FIG. 11C , FIG. 11D ) after a single intrathecal administration.
  • the significance and duration of the analgesia was dose-dependent.
  • Hindpaw formalin injection is a commonly used model for injury-induced pain. The injection induces a characteristic, bi-phasic flinching behavior, which indicates pain in test animals. As shown in FIG. 11E , animals pretreated with intrathecal injection of Protoxin-II variant 63955918 demonstrated fewer flinches in the formalin test, suggesting an inhibition of injury-induced pain.
  • peptides NV1D2775-OH and NV1D3034 demonstrated significant efficacy in the tail flick, hot plate and formalin test ( FIG. 12A , FIG. 12B , FIG. 12C , FIG. 12D , FIG. 12E , FIG. 13A , FIG. 13B , FIG. 13C , FIG. 13D , FIG. 13E ) following a single intrathecal administration.
  • Protoxin-II variants were designed and expressed using the strategies and methods described in Example 6, and characterized in FLPR Tetra and/or Qpatch according to the protocols described in Example 3.
  • Table 18 shows the amino acid sequence of the select generated Protoxin-II variants.
  • Protoxin-II variant 63955918 has W7Q and W30L substitutions when compared to the wild type Protoxin-II. As described in Example 6, mutation of both Trp7 and Trp30 alone or in combination improves folding of the resulting ProtoxinII variants, and could rescue folding of difficult-to-refold Protoxin-II variants.
  • Table 21 shows the IC 50 values and/or percent block (% blk) (% inhibition of currents in comparison to a control sample). Se: standard error.
  • W7 and W30 substitutions were also designed on a variety of family 3 inhibitory cysteine knot peptides to assess whether the improved selectivity and improved refolding properties conferred by those mutations extended beyond Protoxin-II to other highly homologous peptide sequences.
  • Family 3 spider toxins that inhibit Nav channels as defined by Klint et. al. (Toxicon 60:478-491, 2012), were chosen as scaffolds for incorporation of Q at position 7 and L at position 30 (numbering based on Seq ID NO: 1).
  • sequences include beta-theraphotoxin-Gr1c, beta-theraphotoxin-Gr1e, beta/kappa-theraphotoxin-Cg2a, kappa-theraphotoxin-Psla, kappa-theraphotoxin-Pslb, kappa-theraphotoxin-Gr2b, kappa-theraphotoxin-Gr2c, kappa-theraphotoxin-Gr2d, kappa-theraphotoxin-Cg2a, kappatheraphotoxin-Cg2b, kappa-theraphotoxin-Ec2c, beta-theraphotoxin-Gr1d, beta/kappa-theraphotoxin-Pm2a, kappa-theraphotoxin-Ec2a and kappa-theraphotoxin-Ec2b.
  • Table 22 shows the sequences of the designed variants.
  • the resulting variants incorporating non-natural amino acids are generated by standard solid-phase peptide synthesis and oxidative refolding methods.
  • the variants having a polyethylene glycol (PEG) group attached are generated via standard chemical conjugation methods.
  • the resulting variants are tested for their ability to inhibit Nav1.7 in veratridine-induced depolarization inhibition assay and QPatch assays as described in Example 3.
  • the generated variants are tested for their selectivity using methods described in Example 3.

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Abstract

The present invention relates to Protoxin-II variants, polynucleotides encoding them, and methods of making and using the foregoing.

Description

    CROSS-REFERENCE TO RELATED APPLICATIONS
  • This application is continuation of U.S. application Ser. No. 16/673,750, filed on Nov. 4, 2019, which is a continuation of U.S. application Ser. No. 15/090,328, filed on Apr. 4, 2016, and which claimed the benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Application 62/142,069, filed Apr. 2, 2015; the contents of each are herein incorporated by reference in entirety.
    • FIELD OF THE INVENTION
  • The present invention relates to Protoxin-II variants, synthetic polynucleotides encoding them, and methods of making and using the foregoing.
    • BACKGROUND OF THE INVENTION
  • Voltage-gated sodium channels (VGSC) are present in all excitable cells including cardiac and skeletal muscle cells and central and peripheral neurons. In neuronal cells, sodium channels are responsible for amplifying sub-threshold depolarizations and generating the rapid upstroke of the action potential. As such, sodium channels are essential to the initiation and propagation of electrical signals in the nervous system. Aberrant sodium channel function is thought to underlie a variety of medical disorders (Hubner and Jentsch, Hum Mol Genet 11:2435-45, 2002), including epilepsy (Yogeeswari et al., Curr Drug Targets 5:589-602, 2004), arrhythmia (Tfelt-Hansen et al., J Cardiovasc Electrophysiol 21:107-15, 2010), myotonia (Cannon and Bean, J Clin Invest 120:80-3, 2010), and pain (Cregg et al., J Physiol 588:1897-904, 2010). Sodium channels are typically a complex of various subunits, the principle one being the pore-forming alpha-subunit, which is alone sufficient for function.
  • Nine known members of the family of voltage-gated sodium channel alpha subunits exist in humans, Nav1.1-Nav1.9. The Navl.x subfamily can be pharmacologically subdivided into two groups, the tetrodotoxin (TTX)-sensitive and TTX-resistant. Nav1.7, (a.k.a. PN1 or hNE) is encoded by the SCN9A gene, is TTX-sensitive and is primarily expressed in peripheral sympathetic and sensory neurons. Nav1.7 accumulates at nerve fiber endings and amplifies small sub-threshold depolarizations and acts as a threshold channel that regulates excitability.
  • Nav1.7 function is implicated in various pain states, including acute, inflammatory and/or neuropathic pain. In man, gain of function mutations of Nav1.7 have been linked to primary erythemalgia (PE), a disease characterized by burning pain and inflammation of the extremities (Yang et al., J Med Genet 41:171-4, 2004), and paroxysmal extreme pain disorder (PEPD) (Fertleman et al., Neuron 52:767-74, 2006). Consistent with this observation, non-selective sodium channel blockers lidocaine, mexiletine and carbamazepine can provide symptomatic relief in these painful disorders (Legroux-Crespel et al., Ann Dermatol Venereol 130:429-33, 2003; Fertleman et al., Neuron 52:767-74, 2006).
  • Loss-of-function mutations of Nav1.7 in humans cause congenital indifference to pain (CIP), a rare autosomal recessive disorder characterized by a complete indifference or insensitivity to painful stimuli (Cox et al., Nature 444:894-8, 2006; Goldberg et al, Clin Genet 71:311-9, 2007; Ahmad et al., Hum Mol Genet 16:2114-21, 2007).
  • Single nucleotide polymorphisms in the coding region of SCN9A have been associated with increased nociceptor excitability and pain sensitivity. For example, a polymorphism rs6746030 resulting in R1150W substitution in human Nav1.7 has been associated with osteoarthritis pain, lumbar discectomy pain, phantom pain, and pancreatitis pain (Reimann et al., Proc Natl Acad Sci USA 107:5148-53, 2010). DRG neurons expressing the R1150W mutant Nav1.7 display increased firing frequency in response to depolarization (Estacion et al., Ann Neurol 66:862-6, 2009). A disabling form of fibromyalgia has been associated with SCN9A sodium channel polymorphism rs6754031, indicating that some patients with severe fibromyalgia may have a dorsal root ganglia sodium channelopathy (Vargas-Alarcon et al., BMC Musculoskelet Disord 13:23, 2012).
  • In mice, deletion of the SCN9A gene in nociceptive neurons leads to reduction in mechanical and thermal pain thresholds and reduction or abolition of inflammatory pain responses (Nassar et al., Proc Natl Acad Sci USA 101:1270611, 2004). Ablating SCN9A in all sensory neurons abolished mechanical pain, inflammatory pain and reflex withdrawal responses to heat. Deleting SCN9A in both sensory and sympathetic neurons abolished mechanical, thermal and neuropathic pain, and recapitulated the pain-free phenotype seen in humans with Nav1.7 loss-of-function mutations (Minett et al., Nat Commun 3:791, 2012). Nav1.7 inhibitors or blockers may therefore be useful in the treatment of a wide range of pain associated with various disorders.
  • Spider venoms are known to contain a large number of sodium channel blocking peptides, including Huwentoxin-IV (HwTx-IV) (Peng et al., J Biol Chem 277:47564-71, 2002), Protoxin-I, Protoxin-II (Middleton et al., Biochemistry 41:14734-47, 2002) and Phrixotoxin-III (Bosmans et al., Mol Pharmacol 69:419-29, 2006). There is a need for identification of additional Nav1.7 blockers for treatment of a wide range of pain indications. In particular, there is a need for new Nav1.7 blockers with selectivity for Nav1.7 over other voltage gated sodium channel isoforms.
    • SUMMARY OF THE INVENTION
  • One embodiment of the invention is an isolated Protoxin-II variant that inhibits human Nav1.7 activity, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention is an isolated Protoxin-II variant, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, about 1×10−8 M or less, about 1×10−9 M or less, about 1×10−10 M or less, about 1×10−11 M or less, or about 1×10−12 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7, wherein the Protoxin-II variant has a W7Q and/or a W30L substitution, wherein residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention is an isolated Protoxin-II variant comprising the amino acid sequence of SEQ ID NOs: 30, 40, 44, 52, 56, 59, 65, 78, 109, 110, 111, 114, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 224, 226, 227, 232, 243, 244, 245, 247, 249, 252, 255, 258, 261, 263, 264, 265, 266, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 332, 334, 335, 336, 338, 339, 340, 341, 342, 346, 351, 358, 359, 364, 366, 367, 368, 369, 370, 371, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 434, 435, 436, 437, 438, 439, 440, 441, 442, 443, 444, 445, 446, 447, 448, 449, 450, 451, 452, 453, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463, 464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 475, 476, 477, 478, 479, 480, 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 404, 495, 496, 497, 498, 499, 500, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541, 542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554, 555, 556, 557, 558, 559, 560, 561, 562, 563, 564, 565, 566, 567, 568, 569, 570, 571, 572, 573, 574, 575, 576, 577, 578, 579, 580, 581, 582, 583, 584, 585, 586, 587, 588, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642, 643, 644, 645, 646, 647, 648, 649, 650, 651, 652, 653, 654, 655, 656, 657, 658, 659, 660, 661, 662, 663, 664, 665, 666, 667, 668, 669, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 690, 691, 692, 693, 694, 695, 696, 697, 698, 699, 700, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, 714, 715, 716, 717, 718, 719, 720, 721, 722, 723, 724, 725, 726, 727, 728, 729, 730, 731, 732, 733, 734, 735 or 736.
  • Another embodiment of the invention is an isolated Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 422 (GPYCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH); wherein the amino acid sequence has Q at position 7 and L at position 30, when residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention is an isolated fusion protein comprising the Protoxin-II variant of the invention conjugated to a half-life extending moiety.
  • Another embodiment of the invention is an isolated polynucleotide encoding the Protoxin-II variant of the invention.
  • Another embodiment of the invention is a vector comprising the isolated polynucleotide of the invention.
  • Another embodiment of the invention is a host cell comprising the vector of the invention.
  • Another embodiment of the invention is a method of producing the isolated Protoxin-II variant of the invention, comprising culturing the host cell of the invention and recovering the Protoxin-II variant produced by the host cell.
  • Another embodiment of the invention is a pharmaceutical composition comprising the isolated Protoxin-II variant or fusion protein of the invention and a pharmaceutically acceptable excipient.
  • Another embodiment of the invention is a method of treating Nav1.7-mediated pain in a subject, comprising administering to a subject in need thereof an effective amount of the Protoxin-II variant or the fusion protein of the invention to treat the pain.
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 shows the genus amino acid sequence of Protoxin-II variants that inhibit Nav1.7 with an IC50 value of 30 nM or less in a veratridine-induced depolarization inhibition assay. Residue numbering is according to wild-type ProtoxinII of SEQ ID NO: 1. Genus SEQ ID NO: 403.
  • FIG. 2 shows the IC50 values for Nav1.7 and Nav1.6 inhibition in a QPatch assay, and selectivity of each variant calculated by ratio of IC50(Nav1.6)/IC50(Nav1.7) obtained in QPatch assay. SE: standard error.
  • FIG. 3 shows the sequences and the genus sequence of Protoxin-II variants that inhibit Nav1.7 with an IC50 value of 30 nM or less in a veratridine-induced depolarization inhibition assay, and are over 30-fold selective over Nav1.6. Selectivity of each variant was calculated by ratio of IC50(Nav1.6)/IC50(Nav1.7) obtained in QPatch assay. Residue numbering is according to wild-type Protoxin-II of SEQ ID NO: 1.
  • FIG. 4A shows efficacy of NV1D3034 (NV1D3034-OH) (SEQ ID NO: 78) against CFA-induced thermal hyperalgesia in mice, assessed by measurement of paw withdrawal latency in the Hargreaves test before (pre-CFA) and after CFA injection (0) and 1-day after peptide administration (1). ***P<0.001 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 4B shows efficacy of NV1D3034 (NV1D3034-OH) (SEQ ID NO: 78) in CFA-induced thermal hyperalgesia in mice, expressed as percent MPE (maximum possible effect) (MPE %) at each dose on day 1 following peptide administration. *P<0.05 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 5A shows efficacy of NV1D3368 (NV1D3368-OH) (SEQ ID NO: 198) against CFA-induced thermal hyperalgesia in mice, assessed by measurement of paw withdrawal latency in the Hargreaves test before (pre-CFA) and after CFA injection (0) and 1-day after peptide administration (1). **P<0.01 and ****P<0.0001 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 5B shows efficacy of NV1D3368 (NV1D3368-OH) (SEQ ID NO: 198) in CFA-induced thermal hyperalgesia in mice, expressed as percent MPE (MPE %) at each dose on day 1 following peptide administration. *P<0.05 and **P<0.01 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 6A shows efficacy of NV1D2775-OH (SEQ ID NO: 56) against CFA-induced thermal hyperalgesia in mice, assessed by measurement of paw withdrawal latency in the Hargreaves test before (pre-CFA) and after CFA injection (0) and 1-day after peptide administration (1). ****P<0.0001 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 6B shows efficacy of NV1D2775-OH (SEQ ID NO: 56) in CFA-induced thermal hyperalgesia in mice, expressed as percent MPE (MPE %) at each dose on day 1 following peptide administration. ***P<0.001 and ****P<0.0001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 6C shows efficacy of NV1D2775-OH (SEQ ID NO: 56) against CFA-induced tactile allodynia in mice. Tactile thresholds of hind paw before (pre-CFA) and after CFA (0) and 1-day after peptide administration (1). ****P<0.0001 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 6D shows efficacy of NV1D2775-OH (SEQ ID NO: 56) against CFA-induced tactile allodynia in mice, expressed as percent MPE (MPE %) on day 1 following peptide. ***P<0.001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 7A shows time course of NV1D2775-OH mediated reversal of thermal hyperalgesia in the mouse CFA model as assessed by measurement of paw withdrawal latency in the Hargreaves test before and after CFA and at various time points post-peptide administration. **P<0.01 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison. Shaded areas indicate compound delivery period (0-24 hr).
  • FIG. 7B shows time course of NV1D2775-OH mediated reversal of tactile allodynia in the mouse CFA model as assessed by measurement of tactile threshold before and after CFA and at various time points post-peptide administration. **P<0.01 vs. PBS, two-way ANOVA followed by Bonferroni's multiple comparison. Shaded areas indicate compound delivery period (0-24hr).
  • FIG. 8 shows that NV1D2775-OH produced significant analgesia in the mouse hotplate test. Thermal withdrawal latency was evaluated at 50 and 55° C. pre- and post-pump implantation. Pump implantation had no impact on the latency in the control PBS group. One day after pump, NV1D2775-OH treated-mice exhibited prolonged latency compared to the PBS group. *P<0.05 and ****P<0.0001 vs. PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 9 shows that NV1D2775-OH pretreatment protected animals from carrageenan-induced thermal hyperalgesia in mice. Paw withdrawal latencies were measured pre- and on day 1 post-pump before intraplantar carrageenan injection. Latencies were measured again at 2, 3 and 4 hr following carrageenan.
  • FIG. 10 shows the surface representation of the NMR structure of the wild type Protoxin-II. A hydrophobic face shown on left includes residues W5, M6, W7, L23 and W24. A selectivity face is shown on the right and includes residues S11, E12, K14, E17, G18, L29 and W30. Residue numbering is according to SEQ ID NO: 1.
  • FIG. 11A shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) after a single intrathecal (IT) administration in the rat tail flick test. Tail withdrawal latency to a thermal stimulus was measured at the indicated time post-peptide administration.
  • FIG. 11B shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) in the rat tail flick test expressed as percent area under the curve(AUC %) in the first 120min after a single intrathecal (IT) administration. ***P<0.001 and ****P<0.0001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 11C shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) after a single intrathecal (IT) administration in the rat hot plate test (52.5° C.). The latency of a nociceptive response on a hot plate was measured at the indicated time post-peptide administration.
  • FIG. 11D shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) in the hot plate test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. ***P<0.001 and ****P<0.0001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 11E shows efficacy of the Protoxin-II variant 63955918 (SEQ ID NO: 422) in the rat formalin test. Injection of formalin into the rat hindpaw induced a bi-phasic flinching behavior. Total number of flinches in Phase I (0-10 min post formalin) and Phase II (11-60 min post formalin) was measured by an automated device. No statistics were performed in E) due to small group size.
  • FIG. 12A shows efficacy of NV1D2775-OH after a single intrathecal (IT) administration in the rat tail flick test. Tail withdrawal latency to a thermal stimulus was measured at the indicated time post-peptide administration.
  • FIG. 12B shows efficacy of NV1D2775-OH in the rat tail flick test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. *P<0.05 and **P<0.01 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 12C shows efficacy of NV1D2775-OH after a single intrathecal (IT) administration in the rat hot plate test (52.5° C.). The latency of a nociceptive response on a hot plate was measured at the indicated time post-peptide administration.
  • FIG. 12D shows efficacy of NV1D2775-OH in the rat hot plate test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. **P<0.01 and ****P<0.0001 vs PBS, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 12E shows efficacy of NV1D2775-OH in the formalin test. Injection of formalin into the rat hindpaw induced a bi-phasic flinching behavior. Total number of flinches in Phase I (0-10 min post formalin) and Phase II (11-60 min post formalin) was measured by an automated device. **P<0.01 vs PBS, phase I, *P<0.05 vs PBS, phase II, one-way ANOVA followed by Bonferroni's multiple comparison.
  • FIG. 13A shows efficacy of NV1D3034-OH after a single intrathecal (IT) administration in the rat tail flick test. Tail withdrawal latency to a thermal stimulus was measured at the indicated time post-peptide administration.
  • FIG. 13B shows efficacy of NV1D3034-OH in the rat tail flick test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. ***P<0.005 vs PBS, t-test.
  • FIG. 13C shows efficacy of NV1D3034-OH after a single intrathecal (IT) administration in the rat hot plate test (52.5° C.). The latency of a nociceptive response on a hot plate was measured at the indicated time post-peptide administration.
  • FIG. 13D shows efficacy of NV1D3034-OH in the rat hot plate test expressed as percent area under the curve (AUC %) in the first 120 min after a single intrathecal (IT) administration. **P<0.01 vs PBS, t-test.
  • FIG. 13E shows efficacy of NV1D3034-OH in the rat formalin test. Injection of formalin into the rat hindpaw induced a bi-phasic flinching behavior. Total number of flinches in Phase I (0-10 min post formalin) and Phase II (11-60 min post formalin) was measured by an automated device. *P<0.05 vs PBS, phase I, **P<0.01 vs PBS, phase II, t-test.
  • FIG. 14 shows the amino acid alignment of the Family 3 cysteine knot toxin peptides(SEQ ID NOS 738-740, 1 and 741-755, respectively, in order of appearance).
    •  DETAILED DESCRIPTION OF THE INVENTION
  • All publications, including but not limited to patents and patent applications, cited in this specification are herein incorporated by reference as though fully set forth.
  • As used herein and in the claims, the singular forms “a,” “and,” and “the” include plural reference unless the context clearly dictates otherwise.
  • Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which an invention belongs. Although any compositions and methods similar or equivalent to those described herein can be used in the practice or testing of the invention, exemplary compositions and methods are described herein.
  • The term “polypeptide” means a molecule that comprises at least two amino acid residues linked by a peptide bond to form a polypeptide. Small polypeptides of less than 50 amino acids may be referred to as “peptides.” Polypeptides may also be referred as “proteins.”
  • The term “complementary sequence” means a second isolated polynucleotide sequence that is antiparallel to a first isolated polynucleotide sequence and that comprises nucleotides complementary to the nucleotides in the first polynucleotide sequence.
  • The term “vector” means a non-natural polynucleotide capable of being duplicated within a biological system or that can be moved between such systems. Vector polynucleotides typically contain a cDNA encoding a protein of interest and additional elements, such as origins of replication, polyadenylation signal or selection markers, that function to facilitate the duplication or maintenance of these polynucleotides in a biological system. Examples of such biological systems may include a cell, virus, animal, plant, and reconstituted biological systems utilizing biological components capable of duplicating a vector. The polynucleotide comprising a vector may be DNA or RNA molecules or a hybrid of these.
  • The term “expression vector” means a vector that can be utilized in a biological system or a reconstituted biological system to direct the translation of a polypeptide encoded by a polynucleotide sequence present in the expression vector.
  • The term “variant” as used herein refers to a polypeptide or a polynucleotide that differs from wild type Protoxin-II polypeptide of SEQ ID NO: 1 or the polynucleotide encoding the wild type Protoxin-II having the sequence of SEQ ID NO: 107 by one or more modifications for example, substitutions, insertions or deletions of nucleotides or amino acids.
  • Throughout the specification, residues that are substituted in the Protoxin-II variants are numbered corresponding to their position in the wild-type Protoxin-II of SEQ ID NO: 1. For example, “Y1A” in the specification refers to the substitution of tyrosine at residue position that corresponds to the position 1 in the wild type Protoxin-II of SEQ ID NO:1 with alanine.
  • “Complementary DNA” or “cDNA” refers to a well-known synthetic polynucleotide that shares the arrangement of sequence elements found in native mature mRNA species with contiguous exons, with the intervening introns present in genomic DNA are removed. The codons encoding the initiator methionine may or may not be present in cDNA. cDNA may be synthesized for example by reverse transcription or synthetic gene assembly.
  • “Synthetic” or “non-natural” as used herein refers to a polynucleotide or a polypeptide molecule not present in nature.
  • “Nav1.7” (also referred to as hNE or PN1) or “hNav1.7” as used herein refers to the well-known human sodium channel protein type 9 subunit alpha having a sequence shown in GenBank accession number NP 002968.1 and in SEQ ID NO: 79.
  • The term “wild type Protoxin-II” or “wild type ProTx-II” as used herein refers to the tarantula Thrixopelma pruriens (Peruvian green velvet tarantula) toxin peptide having the amino acid sequence YCQKWMWTCDSERKCCEGMVCRLWCKKKLW-COOH (SEQ ID NO: 1) as described in Middleton et al., Biochemistry 41(50):14734-47, 2002.
  • The term “recombinant Protoxin-II” or “recombinant ProT-II” as used herein refers to the recombinant Protoxin-II obtained from expression and subsequent cleavage of a Protoxin-II fusion protein having the sequence of GPYCQKWMWTCDSERKCCEGMVCRLWCKKKLW-OH as shown in SEQ ID NO: 2. Recombinant Protoxin-II incorporates a two amino acid N-terminal extension (residues G and P) when compared to the wild type Protoxin-II.
  • “Blocks human Nav1.7 activity” or “inhibits human Nav1.7 activity” as used herein refers to the ability of the Protoxin-II variant of the invention to reduce membrane depolarization induced by veratridine (3-veratroylveracevine) with an IC50 value of about 1×10−7 M or less in a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET), where veratridine-induced depolarization is measured as a reduction in FRET signal using DISBAC2(3) ([bis-(1,3-diethylthiobarbituric acid) trimethine oxonol]) as an acceptor and PTS18 (trisodium 8-octadecyloxypyrene-1,3,6-trisulfonate) as a donor by exciting the donor at 390-420 nm and measuring FRET at 515-575 nm in a cell line stably expressing human Nav1.7. Ability of the Protoxin-II variants of the invention to block human Nav1.7 activity may also be measured using QPatch electrophysiology at single or several Protoxin-II variant concentrations according to protocol described in Example 3. The Protoxin-II variant of the invention blocks human Nav1.7 activity when it inhibits Nav1.7 currents measured using QPatch by at least about 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when using the assay protocol described in Example 3.
  • “Veratridine-induced depolarization inhibition assay” as used herein refers to the assay described in Example 3.
  • “QPatch assay” or “QPatch electrophysiology assay” as used herein refers to the assay described in Example 3.
  • The term “substantially identical” as used herein means that the two Protoxin-II variant amino acid sequences being compared are identical or have “insubstantial differences.” Insubstantial differences are substitutions of 1, 2, 3, 4, 5, 6, or 7 amino acids in the Protoxin-II variant amino acid sequence that do not adversely affect peptide properties. Amino acid sequences substantially identical to the Protoxin-II variants disclosed herein are within the scope of the application. In some embodiments, the sequence identity can be about 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher. Percent identity can be determined for example by pairwise alignment using the default settings of the AlignX module of Vector NTI v.9.0.0 (Invitrogen, Carlsbad, Calif.). The protein sequences of the present invention may be used as a query sequence to perform a search against public or patent databases, for example, to identify related sequences. Exemplary programs used to perform such searches are the XBLAST or BLASTP programs (http //www ncbi nlm/nih gov), or the GenomeQuest™ (GenomeQuest, Westborough, Mass.) suite using the default settings.
  • Abbreviations of natural amino acids as used herein are shown in Table 1.
  • TABLE 1
    Three One
    Amino letter letter
    acid code code
    Alanine Ala A
    Arginine Arg R
    Asparagine Asn N
    Aspartate Asp D
    Cysteine Cys C
    Glutamate Glu E
    Glutamine Gln Q
    Glycine Gly G
    Histidine His H
    Isoleucine Ile I
    Leucine Leu L
    Lysine Lys K
    Methionine Met M
    Phenylalanine Phe F
    Proline Pro P
    Serine Ser S
    Threonine Thr T
    Tryptophan Trp W
    Tyrosine Tyr Y
    Valine Val V
  • The present invention provides isolated Protoxin-II (ProTx-II) variant polypeptides that inhibit human Nav1.7 activity, polynucleotides encoding them, vectors, host cells, and methods of using the polynucleotides and polypeptides of the invention. The polypeptides of the invention inhibit depolarization/currents resulting from Nav1.7 activation, and therefore may be useful in the treatment of various conditions associated with pain and conditions associated with sensory or sympathetic neuron dysfunction.
  • The variants of the invention are potent inhibitors of Nav1.7. The current invention is based, at least in part, on the finding that certain residue substitutions in Protoxin-II enhance selectivity, synthetic yield and/or homogeneity without adversely affecting the potency of the generated Protoxin-II variants, specifically W7 and M19, and additionally residues Y1 and S11, and further additionally residues E12, R22 and (residue numbering according to SEQ ID NO: 1). For example, substitutions at positions W7 and W30 enhance the Protoxin-II variant folding and improve yield. Substitutions at positions S11, E12, K14, E17, G18, L29 and W30 improve selectivity of the resulting Protoxin-II variants to Nav1.7.
  • One embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, about 1×10−8 M or less, about 1×10−9 M or less, about 1×10−10 M or less, about 1×10−11 M or less, or about 1×10−12 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, about 1×10−8 M or less, about 1×10−9 M or less, about 1×10−10 M or less, about 1×10−11 M or less, or about 1×10−12 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1.
  • Another embodiment of the invention of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant that inhibits human Nav1.7 activity, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant has a W7Q substitution.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant has a W30L substitution.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant has a W7Q and a W30L substitution.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant inhibits Nav1.7 activity by at least 25%, 30%, 35%, 40%, 45%,50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when the Nav1.7 activity is measured using QPatch assay according to protocol described in Example 3.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant has a substitution at one or more residue positions Y1, W7, S11, E12, K14, E17, G18, R22, L29 and W30, when residue numbering is according to SEQ ID NO: 1.
  • Substitutions at position Y1 improve potency to human Nav1.7.
  • Substitutions at position W7 improve Protoxin-II variant folding and protein yield.
  • Substitutions at position S11 improve selectivity to human Nav1.7.
  • Substitutions at position E12 improve selectivity to human Nav1.7.
  • Substitutions at position K14 improve selectivity to human Nav1.7.
  • Substitutions at position E17 improve selectivity to human Nav1.7.
  • Substitutions at position G18 improve selectivity to human Nav1.7.
  • Substitutions at position L29 improve selectivity to human Nav1.7.
  • Substitutions at position W30 improve Protoxin-II variant folding and protein yield and selectivity to Nav1.7.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence YCQKWMQTCDSERKCCEGMVCRLWCKKKLW-COOH (SEQ ID NO: 424); wherein residue Y1, S11, E12, K14, E17, G18, L29 and/or W30 is substituted with any other amino acid shown in Table 1 or a non-natural amino acid, optionally having an N-terminal extension or a C-terminal extension.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence YCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH (SEQ ID NO: 425); wherein residue Y1, S11, E12, K14, E17, G18, M19, L29 and/or W30 is substituted with any other amino acid shown in Table 1 or a non-natural amino acid, optionally having an N-terminal extension or a C-terminal extension.
  • In some embodiments, the Protoxin-II variant of the invention described herein, including in the numbered embodiments listed below, contains at least one a non-natural amino acid.
  • Non-natural amino acids include amino β-alanine ((β-Ala) and other omega-amino acids such as 3-aminopropionic acid (Dap), 2,3-diaminopropionic acid (Dpr), 4-aminobutyric acid and so forth; α-aminoisobutyric acid (Aib); ε-aminohexanoic acid (Aha); δ-aminovaleric acid (Ava); N-methylglycine or sarcosine (MeGly); ornithine (Om); citrulline (Cit); t-butylalanine (t-BuA); t-butylglycine (t-BuG); Nmethylisoleucine (Melle); phenylglycine (Phg); cyclohexylalanine (Cha); norleucine (Nle); 2-naphthylalanine (2-Nal); 4-chlorophenylalanine (Phe(4-C1)); 2-fluorophenylalanine (Phe(2-F)); 3-fluorophenylalanine (Phe(3-F)); 4-fluorophenylalanine (Phe(4-F)); penicillamine (Pen); 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic); α-2-thienylalanine (Thi); methionine sulfoxide (MSO); N(omega)-methyl-L-arginine; N(omega),N(omega)-dimethyl-L-arginine (asymmetrical); 4-guanidino-L-phenylalanine; L-Lys(N-epsilon-(N-alpha-palmitoyl-L-gamma-glutamyl); L-asparagyl-4-aminobutane; L-glutamyl-4-aminobutane; homoarginine (hArg); N-acetyl lysine (AcLys); 2,3-diaminobutyric acid (Dab); 2,4-diaminobutyric acid (Dbu); p-am inophenylalanine (Phe(pNH2)); N-methyl valine (MeVal); homocysteine (hCys) and homoserine (hSer); 4-bromophenylalanine (Phe(4-Br); 5-bromotryphophan (Trp(5-Br)); 3-chlorotyrosine (Tyr(3-C1)) or beta-chloroalanine.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • (SEQ ID NO: 432)
    X1X2X3CX4X5WX6QX7CX8X9X10X11X12CCX13
    X14X15X16CX17LWCX18KKLX19,

    wherein
  • X1 is G, P, A or deleted;
  • X2 is P, A or deleted;
  • X3 is S, Q, A, R or Y;
  • X4 is Q, R, K, A, S or Y;
  • X5 is K, S, Q or R;
  • X6 is M or F;
  • X7 is T, S, R, K or Q;
  • X8 is D, T or asparagyl-4-aminobutane;
  • X9 is S, A, R, I or V;
  • X10 is E, R, N, K, T, Q, Y or glutamyl-4-aminobutane;
  • X11 is R or K;
  • X12 is K, Q, S, A or F;
  • X13 is E, Q, D, L, N or glutamyl-4-aminobutane;
  • X14 is G, Q or P;
  • X15 is M or F;
  • X16 is V or S;
  • X17 is R, T or N-omega methyl L-arginine; and
  • X18 is K or R; and
  • X19 is W or L,
  • optionally having an N-terminal extension or a C-terminal extension.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • (SEQ ID NO: 737)
    X1X2X3CQKWMQTCDX4X5RX6CCX7
    X8X9VCRLWCKKKX10X11;

    wherein
  • X1 is G, P, A or deleted;
  • X2 is P, A or deleted;
  • X3 is S, Q, A, R or Y;
  • X4 is S, A, R, I or V;
  • X5 is E, R, N, K, T, Q, Y or glutamyl-4-aminobutane;
  • X6 is K, Q, S, A or F;
  • X7 is E, Q, D, L, N or glutamyl-4-aminobutane;
  • X8 is G, Q or P;
  • X9 is M or F;
  • X10 is L, V; and
  • X11 is W or L.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant inhibits Nav1.7 activity by at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when the Nav1.7 activity is measured using QPatch assay according to protocol described in Example 3.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the N-terminal extension comprises the amino acid sequences of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the C-terminal extension comprises the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the N-terminal and/or the C-terminal extension is conjugated to the Protoxin-II variant via a linker.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the linker comprises the amino acid sequence of SEQ ID NOs: 383, 392, 398, 399, 400, 401 or 402.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the N-terminal extension consists of the amino acid sequences of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the C-terminal extension consists of the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the linker consists of the amino acid sequence of SEQ ID NOs: 383, 392, 398, 399, 400, 401 or 402.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • (SEQ ID NO: 403)
    X1X2X3CX4X5WX6QX7CX8X9X10X11X12
    CCX13X14FX15CX16LWCX17KKLW,

    wherein
  • X1 is G, P, A or deleted;
  • X2 is P, A or deleted;
  • X3 is S, Q, A, R or Y;
  • X4 is Q, R, K, A or S;
  • X5 is K, S, Q or R;
  • X6 is M or F;
  • X7 is T, S, R, K or Q;
  • X8 is D or T;
  • X9 is S, A or R;
  • X10 is E, R, N, K, Tor Q;
  • X11 is R or K;
  • X12 is K, Q, S or A;
  • X13 is E, Q or D;
  • X14 is G or Q;
  • X15 is V or S;
  • X16 is R or T; and
  • X17 is K or R;
  • optionally having an N-terminal extension or a C-terminal extension, wherein the polypeptide inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below are potent Nav1.7 inhibitors. Recombinant Protoxin-II (SEQ ID NO: 2) has an IC50 value of about 4×10−9 M for human Nav1.7 in a veratridine-induced depolarization inhibition assay measuring decline in FRET (fluorescence resonance energy transfer) in cells stably expressing Nav1.7 using FLIPR® Tetra instrument (Molecular Devices) using experimental details described in Example 3. A Protoxin-II variant is “a potent” Nav1.7 inhibitor when the IC50 value in the assay described above and in Experiment 3 is about 30×10−9 M or less, i.e. within 10 fold of recombinant Protoxin-II. For clarity, an IC50 of 30×10−9 M is identical to IC50 of 3.0×10−8 M.
  • The Protoxin-II variant polypeptides of the invention disclosed herein, including in the numbered embodiments listed below may be produced by chemical synthesis, such as solid phase peptide synthesis, on an automated peptide synthesizer. Alternatively, the polypeptides of the invention may be obtained from polynucleotides encoding the polypeptides by the use of cell-free expression systems such as reticulocyte lysate based expression systems, or by recombinant expression systems. Those skilled in the art will recognize other techniques for obtaining the polypeptides of the invention. In an exemplary method, the Protoxin-II variants of the invention are generated by expressing them as human serum albumin (HSA) fusion proteins utilizing a glycine-rich linker such as (GGGGS)4 (SEQ ID NO:80) or (GGGGS)6 (SEQ ID NO: 81) coupled to a protease cleavable linker such as a recognition sequence for HRV3C protease (Recombinant type 14 3C protease from human rhinovirus) LEVLFQGP (HRV3C linker) (SEQ ID NO: 82), and cleaving the expressed fusion proteins with the HRV3C protease to release the recombinant Protoxin-II variant peptides. Hexahistidine (SEQ ID NO: 108) or other tags may be used to facilitate purification using well known methods.
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be purified using methods described herein. In an exemplary method, Protoxin-II variants of the invention expressed as HSA fusion proteins and cleaved with HRV3C protease may be purified using sold phase extraction (SPE) as described herein.
  • Generation of the Protoxin-II variants disclosed herein, including in the numbered embodiments listed below optionally having N-terminal and/or C-terminal extensions, and Protoxin-II variant fusion proteins is typically achieved at the nucleic acid level. The polynucleotides may be synthesized using chemical gene synthesis according to methods described in U.S. Pat. Nos. 6,521,427 and 6,670,127, utilizing degenerate oligonucleotides to generate the desired variants, or by standard PCR cloning and mutagenesis. Libraries of variants may be generated by standard cloning techniques to clone the polynucleotides encoding the Protoxin-II variants into the vector for expression.
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may incorporate additional N- and/or C-terminal amino acids when compared to the wild type Protoxin-II of SEQ ID NO: 1, for example resulting from cloning and/or expression schemes. For example, cleavage from HSA after expression of the variant as HSA-linker-HRV3C cleavable peptide-Protoxin-II variant fusion protein may result in the incorporation of additional two residues to the N-terminus of each Protoxin-II variant, such as G and P.
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below are tested for their ability to inhibit human Nav1.7 using methods described herein. An exemplary assay is a veratridine-induced depolarization inhibition assay measuring decline in FRET (fluorescence resonance energy transfer) in cells stably expressing Nav1.7. Another exemplary assay employs electrophysiological recordings to measure changes in Nav1.7-mediated currents using well known patch clamp techniques and as described herein.
  • Another embodiment of the invention is an isolated Protoxin-II variant disclosed herein, including in the numbered embodiments listed below comprising the amino acid sequence of SEQ ID NOs: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 224, 226, 227, 232, 243, 244, 245, 247, 249, 252, 255, 258, 261, 263, 264, 265, 266, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 332, 334, 335, 336, 338, 339, 340, 341, 342, 346, 351, 358, 359, 364, 366, 367, 368, 369, 370, 371, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 434, 435, 436, 437, 438, 439, 440, 441, 442, 443, 444, 445, 446, 447, 448, 449, 450, 451, 452, 453, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463, 464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 475, 476, 477, 478, 479, 480, 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 404, 495, 496, 497, 498, 499, 500, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541, 542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554, 555, 556, 557, 558, 559, 560, 561, 562, 563, 564, 565, 566, 567, 568, 569, 570, 571, 572, 573, 574, 575, 576, 577, 578, 579, 580, 581, 582, 583, 584, 585, 586, 587, 588, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642, 643, 644, 645, 646, 647, 648, 649, 650, 651, 652, 653, 654, 655, 656, 657, 658, 659, 660, 661, 662, 663, 664, 665, 666, 667, 668, 669, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 690, 691, 692, 693, 694, 695, 696, 697, 698, 699, 700, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, 714, 715, 716, 717, 718, 719, 720, 721, 722, 723, 724, 725, 726, 727, 728, 729, 730, 731, 732, 733, 734, 735 or 736.
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may inhibit human Nav1.7 with an IC50 value of about 1×10−7 M or less, about 1×10−8 M about 1×10−9 or less, about 1×10−19 M or less, about 1×10−11 M or less, or about 1×10−12 M or less. Exemplary variants demonstrating the range of IC50 values are variants having amino acid sequences shown in SEQ ID NOs: 30, 40, 44, 52, 56, 59, 65, 78, 109, 110, 111, 114, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 224, 226, 227, 232, 243, 244, 245, 247, 249, 252, 255, 258, 261, 263, 264, 265, 266, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 332, 334, 335, 336, 338, 339, 340, 341, 342, 346, 351, 358, 359, 364, 366, 367, 368, 369, 370, 371, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, or 431.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the Protoxin-II variant inhibits Nav1.7 activity by at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% when the Nav1.7 activity is measured using QPatch assay according to protocol described in Example 3. Exemplary variants inhibiting Nav1.7 activity by at least 25% in a QPatch assay are variants having amino acid sequences shown in SEQ ID NOs: 109, 133, 408, 409, 410, 412, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 434, 436, 437, 438, 439, 440, 441, 442, 444, 446, 447, 448, 450, 452, 453, 455, 456, 459, 460, 461, 462, 463, 464, 465, 466, 468, 469, 470, 471, 473, 474, 476, 477, 478, 479, 480, 482, 483, 485, 486, 487, 490, 491, 492, 494, 495, 496, 497, 498, 499, 500, 502, 504, 505, 507, 508, 510, 511, 512, 514, 516, 517, 518, 519, 521, 522, 523, 524, 526, 529, 531, 532, 533, 537, 546, 554, 557, 559, 560, 561, 562, 563, 566, 571, 579, 588, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 621, 622, 632, 633, 634, 635, 636, 637, 638, 639, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680. 681, 682, 683, 684 and 685.
  • Table 2, Table 3, Table 14, and Table 18 show the sequences of select Protoxin-II variants.
  • TABLE 2
    Protoxin-II
    variant SEQ
    Protein peptide ID Protein amino acid
    name name NO: sequence
    wild type  1 YCQKWMWTCDSERKCCEGM
    VCRLWCKKKLW-COOH
    NV1D12  2 GPYCQKWMWTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D748  3 GPACQKWMWTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D751  4 GPQCQKWMWTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2292  5 GPRCQKWMWTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D750  6 GPSCQKWMWTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D1328  7 GPYCQKWFWTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D774  8 GPYCQKWMQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D786  9 GPYCQKWMWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2300 10 GPYCQKWMWTCDRERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D791 11 GPYCQKWMWTCDSKRKCCE
    GMVCRLWCKKKLW-COOH
    NV1D1332 12 GPYCQKWMWTCDSNRKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2512 13 GPYCQKWMWTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D1336 14 GPYCQKWMWTCDSERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D1337 15 GPYCQKWMWTCDSERKCCE
    GMVCTLWCKKKLW-COOH
    NV1D2308 16 GPYCQKWMWTCDSERKCCE
    GMVCRLWCRKKLW-COOH
    NV1G953 NV1D2670 17 GPACQKWMQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G951 NV1D2674 18 GPACQKWMWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G909 NV1D2664 19 GPACQKWMWTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G963 NV1D2671 20 GPQCQKWMQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G949 NV1D2675 21 GPQCQKWMWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G977 NV1D2665 22 GPQCQKWMWTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G957 NV1D2668 23 GPRCQKWMQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G965 NV1D2672 24 GPRCQKWMWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G973 NV1D2662 25 GPRCQKWMWTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G975 NV1D2669 26 GPSCQKWMQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G971 NV1D2673 27 GPSCQKWMWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G995 NV1D2663 28 GPSCQKWMWTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G961 NV1D2676 29 GPYCQKWMQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G911 NV1D2666 30 GPYCQKWMQTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2816 31 GPACQKWFQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G905 NV1D2735 32 GPACQKWMQTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G919 NV1D2739 33 GPACQKWMWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G979 NV1D2731 34 GPACQKWMQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2810 35 GPQCQKWFQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G1099 NV1D2732 36 GPQCQKWMQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G1011 NV1D2740 37 GPQCQKWMWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2819 38 GPRCQKWFWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G1105 NV1D2729 39 GPRCQKWMQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G1013 NV1D2733 40 GPRCQKWMQTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2814 41 GPSCQKWFQTCDSERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2820 42 GPSCQKWFWTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G983 NV1D2730 43 GPSCQKWMQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G1003 NV1D2734 44 GPSCQKWMQTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1009 NV1D2738 45 GPSCQKWMWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2851 46 GPYCQKWFKTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2850 47 GPYCQKWFQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1G987 NV1D2667 48 GPYCQKWMWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2867 49 GPACQKWFQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2881 50 GPACQKWFQTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2882 51 GPACQKWFQTCDSERKCCE
    GLVCRLWCKKKLW-COOH
    NV1G899 NV1D2774 52 GPACQKWMQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1077 NV1D2902 53 GPACQKWMQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2861 54 GPQCQKWFQTCDAERKCCE
    GMVCRLWCKKKLW-COOH
    NV1D2870 55 GPQCQKWFQTCDSERKCCE
    GLVCRLWCKKKLW-COOH
    NV1G1007 NV1D2775 56 GPQCQKWMQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1067 NV1D2893 57 GPQCQKWMQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2887 58 GPRCQKWFWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1005 NV1D2772 59 GPRCQKWMQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1061 NV1D2896 60 GPRCQKWMQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2877 61 GPSCQKWFQTCDSERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2878 62 GPSCQKWFQTCDSERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2889 63 GPSCQKWFWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2889 64 GPSCQKWFWTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1001 NV1D2773 65 GPSCQKWMQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2890 66 GPSCQKWFWTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1G1109 NV1D2899 67 GPSCQKWMQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2905 68 GPYCQKWFQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2906 69 GPYCQKWFQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2921 70 GPACQKWFQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2922 71 GPACQKWFQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2909 72 GPQCQKWFQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2910 73 GPQCQKWFQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2913 74 GPRCQKWFQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2914 75 GPRCQKWFQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1D2917 76 GPSCQKWFQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1D2918 77 GPSCQKWFQTCDAERKCCE
    GLVCRLWCKKKLW-COOH
    NV1G1153 NV1D3034 78 GPQCQKWMQTCDRERKCCE
    GFVCTLWCRKKLW-COOH
  • TABLE 3
    Protoxin-II variant SEQ ID Protein amino acid
    Protein name peptide name NO: sequence
    (−GP)NV1G1001 (−GP)NV1D2773 109 SCQKWMQTCDAERKCCEGFVCRLW
    CKKKLW-COOH
    (−GP)NV1G1001- (−GP)NV1D2773- 110 SCQKWMQTCDAERKCCEGFVCRLW
    NH-Me NH2 CKKKLW-NH2
    NV1G1007-NH2 NV1D2775-NF2 111 GPQCQKWMQTCDAERKCCEGFVCR
    LWCKKKLW-NH2
    NV1G1107-NH2 NV1D2890-NH2 112 GPSCQKWFWTCDAERKCCEGLVCRL
    WCKKKLW-NH2
    NV1G1137 NV1D2974 113 GPQCQKWMQTCDAERKCCEGFSCT
    LWCKKKLW-COOH
    (−GP)N-Ac- (−GP)N-Ac- 114 Ac-
    NV1G1137-NH2 NV1D2974-NH2 QCQKWMQTCDAERKCCEGFSCTLW
    CKKKLW-NH2
    (−GP)N-Ac- (−GP)N-Ac- 115 Ac-
    NV1G1137- NV1D2974 QCQKWMQTCDAERKCCEGFSCTLW
    CKKKLW-COOH
    NV1G1153 NV1D3034 116 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1153-NH2 NV1D3034-NH2 117 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-NH2
    NV1G1153-NH- NV1D3034-NH- 118 GPQCQKWMQTCDRERKCCEGFVCT
    butyl butyl LWCRKKLW-NH-butyl
    NV1G1153-NH- NV1D3034-NH- 119 GPQCQKWMQTCDRERKCCEGFVCT
    methyl methyl LWCRKKLW-NH-methyl
    (−GP)N-Ac- (−GP)N-Ac- 120 Ac-
    NV1G1153 NV1D3034 QCQKWMQTCDRERKCCEGFVCTLW
    CRKKLW-COOH
    (−GP)N-Ac- (−GP)N-Ac- 121 Ac-
    NV1G1153-NH2 NV1D3034-NH2 QCQKWMQTCDRERKCCEGFVCTLW
    CRKKLW-NH2
    NV1G1818 NV1D3368 122 GPQCQKWMQTCDRTRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1818-NH2 NV1D3368-NH2 123 GPQCQKWMQTCDRTRKCCEGFVCT
    LWCRKKLW-NH2
    NV1G1147 NV1D2969 124 GPSCQKWMQTCDAERKCCEGFSCRL
    WCKKKLW-COOH
    NV1G1145 NV1D2970 125 GPSCQKWMQTCDAERKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1143 NV1D2971 126 GPSCQKWMQTCDAERKCCEGFSCTL
    WCKKKLW-COOH
    NV1G1141 NV1D2972 127 GPQCQKWMQTCDAERKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1139 NV1D2973 128 GPQCQKWMQTCDAERKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1137 NV1D2974 129 GPQCQKWMQTCDAERKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1137-NH2 NV1D2974-NH2 130 GPQCQKWMQTCDAERKCCEGFSCT
    LWCKKKLW-NH2
    NV1G1517 NV1D3004 131 GPQCQKWMQTCDRERKCCEGFVCR
    LWCKKKLW-COOH
    NV1G1515 NV1D3005 132 GPQCQKWMQTCDANRKCCEGFVC
    RLWCKKKLW-COOH
    NV1G1519 NV1D3006 133 GPQCQKWMQTCDARRKCCEGFVCR
    LWCKKKLW-COOH
    NV1G1513 NV1D3007 134 GPQCQKWMQTCDAERKCCEGFVCR
    LWCRKKLW-COOH
    NV1G1523 NV1D3012 135 GPQCQKWMQTCDRNRKCCEGFVC
    RLWCKKKLW-COOH
    NV1G1525 NV1D3013 136 GPQCQKWMQTCDRRRKCCEGFVCR
    LWCKKKLW-COOH
    NV1G1255 NV1D3014 137 GPQCQKWMQTCDRERKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1187 NV1D3015 138 GPQCQKWMQTCDRERKCCEGFVCR
    LWCRKKLW-COOH
    NV1G1257 NV1D3016 139 GPQCQKWMQTCDANRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1221 NV1D3017 140 GPQCQKWMQTCDARRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1521 NV1D3018 141 GPQCQKWMQTCDANRKCCEGFVC
    RLWCRKKLW-COOH
    NV1G1531 NV1D3019 142 GPQCQKWMQTCDARRKCCEGFVCR
    LWCRKKLW-COOH
    NV1G1239 NV1D3020 143 GPQCQKWMQTCDAERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1583 NV1D3030 144 GPQCQKWMQTCDRNRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1527 NV1D3031 145 GPQCQKWMQTCDRRRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1511 NV1D3032 146 GPQCQKWMQTCDRNRKCCEGFVC
    RLWCRKKLW-COOH
    NV1G1509 NV1D3033 147 GPQCQKWMQTCDRRRKCCEGFVCR
    LWCRKKLW-COOH
    NV1G1231 NV1D3035 148 GPQCQKWMQTCDANRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1211 NV1D3036 149 GPQCQKWMQTCDARRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1267 NV1D3044 150 GPQCQKWMQTCDRNRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1269 NV1D3045 151 GPQCQKWMQTCDRRRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1215 NV1D3048 152 GPQCQKWMQTCDAKRKCCEGFVCR
    LWCKKKLW-COOH
    NV1G1593 NV1D3050 153 GPQCQKWMQTCDRKRKCCEGFVCR
    LWCKKKLW-COOH
    NV1G1263 NV1D3051 154 GPQCQKWMQTCDAKRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1585 NV1D3052 155 GPQCQKWMQTCDAKRKCCEGFVCR
    LWCRKKLW-COOH
    NV1G1623 NV1D3056 156 GPQCQKWMQTCDRKRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1613 NV1D3057 157 GPQCQKWMQTCDRKRKCCEGFVCR
    LWCRKKLW-COOH
    NV1G1259 NV1D3058 158 GPQCQKWMQTCDAKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1265 NV1D3062 159 GPQCQKWMQTCDRKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1273 NV1D3109 160 GPQCQKWMWTCDARRKCCEGFVC
    TLWCRKKLW-COOH
    NV1G1225 NV1D3121 161 GPQCQKWMWTCDRKRKCCEGFVC
    TLWCRKKLW-COOH
    NV1G1886 NV1D3249 162 GPAAAAAQCQKWMQTCDAERKCC
    EGFVCRLWCKKKLW-COOH
    NV1G1633 NV1D3251 163 GPAPAPAQCQKWMQTCDAERKCCE
    GFVCRLWCKKKLW-COOH
    NV1G1631 NV1D3252 164 GPQCQKWMQTCDAERKCCEGFVCR
    LWCKKKLWAPAPA-COOH
    NV1G1885 NV1D3254 165 GPQCQKWMQTCDAERKCCEGFVCR
    LWCKKKLWGGGGG-COOH
    NV1G1884 NV1D3256 166 GPCCNCSSKWCRDHSRCCGRGSAPA
    PAPAPAPGSQCQKWMQTCDAERKC
    CEGFVCRLWCKKKLW-COOH
    NV1G1881 NV1D3257 167 GPQCQKWMQTCDAERKCCEGFVCR
    LWCKKKLWGSAPAPAPAPAPGSCCN
    CSSKWCRDHSRCC-COOH
    NV1G1879 NV1D3259 168 GPQCQKWMQTCDAERKCCEGFVCR
    LWCKKKLWGSAPAPAPAPAPAPAPA
    PAPAPGSCCNCSSKWCRDHSRCCGR-
    COOH
    NV1G1883 NV1D3260 169 GPCCNCSSKWCRDHSRCCGRGSAPA
    PAPAPAPAPAPAPAPAPGSQCQKW
    MQTCDAERKCCEGPVCRLWCKKKL
    W-COOH
    NV1G1880 NV1D3261 170 GPQCQKWMQTCDAERKCCEGFVCR
    LWCKKKLWGSAPAPAPAPAPAPAPA
    PAPAPGSCCNCSSKWCRDHSRCC-
    COOH
    NV1G1882 NV1D3262 171 GPCCNCSSKWCRDHSRCCGSAPAPA
    PAPAPAPAPAPAPAPGSQCQKWMQ
    TCDAERKCCEGFVCRLWCKKKLW-
    COOH
    NV1G1776 NV1D3339 172 GPQCRKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1775 NV1D3340 173 GPQCKKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1768 NV1D3341 174 GPQCTKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1777 NV1D3342 175 GPQCAKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1770 NV1D3344 176 GPQCEKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1767 NV1D3345 177 GPQCSKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1769 NV1D3346 178 GPQCQRWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1774 NV1D3347 179 GPQCQTWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1771 NV1D3348 180 GPQCQAWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1778 NV1D3349 181 GPQCQDWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1773 NVID3350 182 GPQCQEWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1779 NV1D3351 183 GPQCQQWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1772 NV1D3352 184 GPQCQSWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1868 NV1D3353 185 GPQCQKWMQRCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1824 NV1D3354 186 GPQCQKWMQKCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1863 NV1D3356 187 GPQCQKWMQDCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1826 NV1D3357 188 GPQCQKWMQECDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1810 NV1D3358 189 GPQCQKWMQQCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1836 NV1D3359 190 GPQCQKWMQSCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1834 NV1D3360 191 GPQCQKWMQTCRRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1829 NV1D3361 192 GPQCQKWMQTCKRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1820 NV1D3362 193 GPQCQKWMQTCTRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1828 NV1D3363 194 GPQCQKWMQTCARERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1827 NV1D3365 195 GPQCQKWMQTCQRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1857 NV1D3366 196 GPQCQKWMQTCSRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1823 NV1D3367 197 GPQCQKWMQTCDRQRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1818 NV1D3368 198 GPQCQKWMQTCDRTRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1811 NV1D3369 199 GPQCQKWMQTCDREKKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1853 NV1D3370 200 GPQCQKWMQTCDRETKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1817 NV1D3371 201 GPQCQKWMQTCDREAKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1814 NV1D3372 202 GPQCQKWMQTCDREDKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1831 NV1D3374 203 GPQCQKWMQTCDREQKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1819 NV1D3375 204 GPQCQKWMQTCDRESKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1859 NV1D3376 205 GPQCQKWMQTCDRERRCCEGFVCT
    LWCRKKLW-COOH
    NV1G1825 NV1D3377 206 GPQCQKWMQTCDRERTCCEGFVCT
    LWCRKKLW-COOH
    NV1G1821 NV1D3378 207 GPQCQKWMQTCDRERACCEGFVCT
    LWCRKKLW-COOH
    NV1G1835 NV1D3379 208 GPQCQDWMQTCDRERDCCEGFVCT
    LWCRKKLW-COOH
    NV1G1815 NV1D3380 209 GPQCQEWMQTCDRERECCEGFVCT
    LWCRKKLW-COOH
    NV1G1833 NV1D3381 210 GPQCQKWMQTCDRERQCCEGFVCT
    LWCRKKLW-COOH
    NV1G1812 NV1D3382 211 GPQCQKWMQTCDRERSCCEGFVCT
    LVVCRKKLW-COOH
    NV1G1782 NV1D3383 212 GPQCQKWMQTCDRERKCCRGFVCT
    LWCRKKLW-COOH
    NV1G1783 NV1D3384 213 GPQCQKWMQTCDRERKCCKGFVCT
    LWCRKKLW-COOH
    NV1G1785 NV1D3385 214 GPQCQKWMQTCDRERKCCTGFVCT
    LWCRKKLW-COOH
    NV1G1784 NV1D3386 215 GPQCQKWMQTCDRERKCCAGFVCT
    LWCRKKLW-COOH
    NV1G1780 NV1D3387 216 GPQCQKWMQTCDRERKCCDGFVCT
    LWCRKKLW-COOH
    NV1G1781 NV1D3388 217 GPQCQKWMQTCDRERKCCQGFVCT
    LWCRKKLW-COOH
    NV1G1786 NV1D3389 218 GPQCQKWMQTCDRERKCCSGFVCT
    LWCRKKLW-COOH
    NV1G1851 NV1D3390 219 GPQCQKWMQTCDRERKCCERFVCT
    LWCRKKLW-COOH
    NV1G1852 NV1D3391 220 GPQCQKWMQTCDRERKCCEKFVCT
    LWCRKKLW-COOH
    NV1G1854 NV1D3392 221 GPQCQKWMQTCDRERKCCETFVCT
    LWCRKKLW-COOH
    NV1G1860 NV1D3393 222 GPQCQKWMQTCDRERKCCEAFVCT
    LWCRKKLW-COOH
    NV1G1789 NV1D3394 223 GPQCQKWMQTCDRERKCCEDFVCT
    LWCRKKLW-COOH
    NV1G1787 NV1D3396 224 GPQCQKWMQTCDRERKCCEQFVCT
    LWCRKKLW-COOH
    NV1G1856 NV1D3397 225 GPQCQKWMQTCDRERKCCESFVCT
    LWCRKKLW-COOH
    NV1G1855 NV1D3398 226 GPQCQKWMQTCDRERKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1788 NV1D3399 227 GPQCQKWMQTCDRERKCCEGFTCT
    LWCRKKLW-COOH
    NV1G1849 NV1D3400 228 GPQCQKWMQTCDRERKCCEGFQCT
    LWCRKKLW-COOH
    NV1G1795 NV1D3401 229 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRRKLW-COOH
    NV1G1803 NV1D3403 230 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRAKLW-COOH
    NV1G1807 NV1D3408 231 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKRLW-COOH
    NV1G1806 NV1D3409 232 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKTLW-COOH
    NV1G1805 NV1D3410 233 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKALW-COOH
    NV1G1809 NV1D3413 234 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKQLW-COOH
    NV1G1850 NV1D3414 235 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKSLW-COOH
    NV1G1793 NV1D3419 236 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLD-COOH
    NV1G1822 NV1D3423 237 GPQCQKWMQTCRRRRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1813 NV1D3424 238 GPQCQKWMQTCKRKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1840 NV1D3425 239 GPQCQKWMQTCRRRDKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1848 NV1D3426 240 GPQCQKWMQTCKRKDKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1841 NV1D3427 241 GPQCQKWMQTCRRREKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1844 NV1D3428 242 GPQCQKWMQTCKRKEKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1842 NV1D3430 243 GPQCQDWMQTCDRERKCCKGFVCT
    LWCRKKLW-COOH
    NV1G1846 NV1D3431 244 GPQCQEWMQTCDRERKCCKGFVCT
    LWCRKKLW-COOH
    NV1G1843 NV1D3432 245 GPQCQEWMQTCDRERKCCRGFVCT
    LWCRKKLW-COOH
    NV1G1892 NV1D3439 246 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLG-COOH
    NV1G1916 NV1D3465 247 GPQCQKFMQTCDRERKCCEGFVCTL
    WCRKKLW-COOH
    NV1G1922 NV1D3466 248 GPQCQKWMQTCDEERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1915 NV1D3467 249 GPQCQKWMQTCDRERKCCGGFVCT
    LWCRKKLW-COOH
    NV1G1924 NV1D3470 250 GPQCQKWMQTCDRERKCCEGLVCT
    LWCRKKLW-COOH
    NV1G1709 NV1D3510 251 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPASPGARAF-COOH
    NV1G1681 NV1D3511 252 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWSPGARAF-COOH
    NV1G1693 NV1D3512 253 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAPAPAPDGPWRK
    M-COOH
    NV1G1705 NV1D3513 254 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPADGPWRKM-
    COOH
    NV1G1689 NV1D3514 255 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWDGPWRKM-COOH
    NV1G1711 NV1D3515 256 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAPAPAPFGQKASS-
    COOH
    NV1G1685 NV1D3516 257 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAFGQKASS-COOH
    NV1G1697 NV1D3517 258 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWFGQKASS-COOH
    NV1G1695 NV1D3518 259 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAPAPAPQRFVTG
    HFGGLYPANG-COOH
    NV1G1701 NV1D3519 260 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAQRFVTGHFGGLY
    PANG-COOH
    NV1G1691 NV1D3520 261 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWQRFVTGHFGGLYPANG-
    COOH
    NV1G1679 NV1D3521 262 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAPAPAPRRRRRRR
    RRRR-COOH
    NV1G1683 NV1D3523 263 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWRRRRRRRRRRR-COOH
    NV1G1707 NV1D3524 264 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAPAPAPYGRKKRR
    QRRR-COOH
    NV1G1713 NV1D3525 265 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAYGRKKRRQRRR-
    COOH
    NV1G1687 NV1D3526 266 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWYGRKKRRQRRR-COOH
    NV1G1699 NV1D3527 267 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPAPAPAP-COOH
    NV1G1675 NV1D3528 268 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPA-COOH
    NV1G1754 NV1D3529 269 GPRCQKWMQTCDAKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1748 NV1D3530 270 GPSCQKWMQTCDAKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1747 NV1D3531 271 GPYCQKWMQTCDAKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1752 NV1D3532 272 GPACQKWMQTCDAKRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1722 NV1D3533 273 GPQCQKWMQTCDAKRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1744 NV1D3534 274 GPRCQKWMQTCDAKRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1742 NV1D3535 275 GPSCQKWMQTCDAKRKCCEGFSCTL
    WCRKKLW-COOH
    NV1G1723 NV1D3536 276 GPYCQKWMQTCDAKRKCCEGFSCTL
    WCRKKLW-COOH
    NV1G1745 NV1D3537 277 GPACQKWMQTCDAKRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1757 NV1D3538 278 GPRCQKWMQTCDRNRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1762 NV1D3539 279 GPSCQKWMQTCDRNRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1763 NV1D3540 280 GPYCQKWMQTCDRNRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1728 NV1D3541 281 GPACQKWMQTCDRNRKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1730 NV1D3542 282 GPQCQKWMQTCDRNRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1760 NV1D3543 283 GPRCQKWMQTCDRNRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1727 NV1D3544 284 GPSCQKWMQTCDRNRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1729 NV1D3545 285 GPYCQKWMQTCDRNRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1867 NV1D3546 286 GPACQKWMQTCDRNRKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1759 NV1D3547 287 GPRCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1758 NV1D3548 288 GPSCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1766 NV1D3549 289 GPYCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1761 NV1D3550 290 GPACQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1726 NV1D3551 291 GPRCQKWMQTCDRERKCCESFSCTL
    WCRKKLW-COOH
    NV1G1721 NV1D3552 292 GPSCQKWMQTCDRERKCCEGFSCTL
    WCRKKLW-COOH
    NV1G1765 NVID3553 293 GPYCQKWMQTCDRERKCCEGFSCTL
    WCRKKLW-COOH
    NV1G1764 NV1D3554 294 GPACQKWMQTCDRERKCCEGFSCT
    LWCRKKLW-COOH
    NV1G1732 NV1D3555 295 GPRCQKWMQTCDAERKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1862 NV1D3556 296 GPYCQKWMQTCDAERKCCEGFSCTL
    WCKKKLW-COOH
    NV1G1751 NV1D3558 297 GPRCQKWMQTCDANRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1866 NV1D3559 298 GPSCQKWMQTCDANRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1865 NV1D3560 299 GPYCQKWMQTCDANRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1716 NV1D3561 300 GPACQKWMQTCDANRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1724 NV1D3562 301 GPRCQKWMQTCDARRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1717 NV1D3563 302 GPSCQKWMQTCDARRKCCEGFSCTL
    WCKKKLW-COOH
    NV1G1743 NV1D3564 303 GPYCQKWMQTCDARRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1720 NV1D3565 304 GPACQKWMQTCDARRKCCEGFSCT
    LWCKKKLW-COOH
    NV1G1735 NV1D3566 305 GPRCQKWMQTCDAERKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1734 NV1D3568 306 GPACQKWMQTCDAERKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1741 NV1D3569 307 GPRCQKWMQTCDARRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1719 NV1D3570 308 GPSCQKWMQTCDARRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1718 NV1D3571 309 GPYCQKWMQTCDARRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1725 NV1D3572 310 GPACQKWMQTCDARRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1869 NV1D3573 311 GPRCQKWMQTCDANRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1755 NV1D3574 312 GPSCQKWMQTCDANRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1756 NV1D3575 313 GPYCQKWMQTCDANRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1746 NV1D3576 314 GPACQKWMQTCDANRKCCEGFVCT
    LWCKKKLW-COOH
    NV1G1733 NV1D3577 315 GPRCQKWMQTCDAERKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1738 NV1D3578 316 GPYCQKWMQTCDAERKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1737 NV1D3579 317 GPACQKWMQTCDAERKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1740 NV1D3580 318 GPRCQKWMQTCDARRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1864 NV1D3581 319 GPSCQKWMQTCDARRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1739 NV1D3582 320 GPYCQKWMQTCDARRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1870 NV1D3583 321 GPACQKWMQTCDARRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1715 NV1D3584 322 GPRCQKWMQTCDANRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1753 NV1D3585 323 GPSCQKWMQTCDANRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1750 NV1D3586 324 GPYCQKWMQTCDANRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1750-NH2 NV1D3586-NH2 325 GPYCQKWMQTCDANRKCCEGFSCR
    LWCKKKLW-NH2
    NV1G1749 NV1D3587 326 GPACQKWMQTCDANRKCCEGFSCR
    LWCKKKLW-COOH
    NV1G1871 NV1D3772 327 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWSHSNTQTLAKAPEHTG-
    COOH
    NV1G1839 NV1D3774 328 GPSHSNTQTLAKAPEHTGAPAPAPA
    PAPAPAPAPAPAPQCQKWMQTCDR
    ERKCCEGFVCTLWCRKKLW-COOH
    NV1G1877 NV1D3775 329 GPSHSNTQTLAKAPEHTGAPAPAPA
    PAPQCQKWMQTCDRERKCCEGFVC
    TLWCRKKLW-COOH
    NV1G1872 NV1D3777 330 GPSHSNTQTLAKAPEHTGQCQKWM
    QTCDRERKCCEGFVCTLWCRKKLW-
    COOH
    NV1G1941 NV1D3782 331 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKAW-COOH
    NV1G1990 NV1D3788 332 GPAAAAAQCQKWMQTCDRERKCC
    EGFVCTLWCRKKLW-COOH
    NV1G1991 NV1D3789 333 GPAPAPAQCQKWMQTCDRERKCCE
    GFVCTLWCRKKLW-COOH
    NV1G1989 NV1D3791 334 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAAAAA-COOH
    NV1G1993 NV1D3792 335 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGGGGG-COOH
    NV1G1967 NV1D3793 336 GPCCNCSSKWCRDHSRCCGRGSAPA
    PAPAPAPAPAPAPAPAPGSQCQKW
    MQTCDRERKCCEGFVCTLWCRKKL
    W-COOH
    NV1G1969 NV1D3795 337 GPCCNCSSKWCRDHSRCCGSAPAPA
    PAPAPAPAPAPAPAPGSQCQKWMQ
    TCDRERKCCEGFVCTLWCRKKLW-
    COOH
    NV1G1974 NV1D3796 338 GPCCNCSSKWCRDHSRCCGSAPAPA
    PAPAPGSQCQKWMQTCDRERKCCE
    GFVCTLWCRKKLW-COOH
    NV1G1950 NV1D3797 339 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGSAPAPAPAPAPAPAPA
    PAPAPGSCCNCSSKWCRDHSRCC-
    COOH
    NV1G1948 NV1D3798 340 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGSAPAPAPAPAPAPAPA
    PAPAPG5CCNCSSKWCRDNSRCCGR-
    COOH
    NV1G2057 NV1D3799 341 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGSAPAPAPAPAPGSCCN
    CSSKWCRDHSRCC-COOH
    NV1G1954 NV1D3800 342 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGSAPAPAPAPAPGSCCN
    CSSKWCRDHSRCCGR-COOH
    NV1G1956 NV1D3801 343 GPSPGARAFAPAPAPAPAPQCQKW
    MQTCDRERKCCEGFVCTLWCRKKL
    W-COOH
    NV1G1961 NV1D3802 344 GPSPGARAFAPAPAQCQKWMQTC
    DRERKCCEGFVCTLWCRKKLW-
    COOH
    NV1G1960 NV1D3803 345 GPSPGARAFQCQKWMQTCDRERKC
    CEGFVCTLWCRKKLW-COOH
    NV1G1977 NV1D3804 346 GPDGPWRKMAPAPAPAPAPQCQK
    WMQTCDRERKCCEGFVCTLWCRKK
    LW-COOH
    NV1G1982 NV1D3805 347 GPDGPWRKMAPAPAQCQKWMQT
    CDRERKCCEGFVCTLWCRKKLW
    COOH
    NV1G1984 NV1D3806 348 GPDGPWRKMQCQKWMQTCDRER
    KCCEGFVCTLWCRKKLW-COOH
    NV1G1985 NV1D3808 349 GPFGQKASSAPAPAQCQKWMQTC
    DRERKCCEGFVCTLWCRKKLW-
    COOH
    NV1G1983 NV1D3809 350 GPFGQKASSQCQKWMQTCDRERKC
    CEGFVCTLWCRKKLW-COOH
    NV1G1973 NV1D3810 351 GPQRPVTGHFGGLYPANGAPAPAPA
    PAPQCQKWMQTCDRERKCCEGFVC
    TLWCRKKLW-COOH
    NV1G1976 NV1D3811 352 GPQRFVTGHFGGLYPANGAPAPAQC
    QKWMQTCDRERKCCEGFVCTLWCR
    KKLW-COOH
    NV1G1980 NV1D3812 353 GPQRFVTGHFGGLYPANGQCQKW
    MQTCDRERKCCEGFVCTLWCRKKL
    W-COOH
    NV1G1952 NV1D3813 354 GPRRRRRRRRRRRAPAPAPAPAPQC
    QKWMQTCDRERKCCEGFVCTLWCR
    KKLW-COOH
    NV1G1957 NV1D3814 355 GPRRRRRRRRRRRAPAPAQCQKWM
    QTCDRERKCCEGFVCTLWCRKKLW-
    COOH
    NV1G1981 NV1D3815 356 GPRRRRRRRRRRRQCQKWMQTCDR
    ERKCCEGFVCTLWCRKKLW-COOH
    NV1G1959 NV1D3818 357 GPYGRKKRRQRRRQCQKWMQTCD
    RERKCCEGFVCTLWCRKKLW-COOH
    NV1G1986 NV1D3819 358 GPAPAPAPAPAPQCQKWMQTCDRE
    RKCCEGFVCTLWCRKKLW-COOH
    NV1G1968 NV1D3822 359 GPGWCGDPGATCGKLRLYCCSGFCD
    SYTKTCKDKSSAGGGGSAPAPAPAPA
    PAPAPAPAPAPAPAPAPAPAPGGGG
    SQCQKWMQTCDRERKCCEGFVCTL
    WCRKKLW-COOH
    NV1G1945 NV1D3823 360 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGGGGSAPAPAPAPAPA
    PAPAPAPAPAPAPAPAPAPGGGGSG
    WCGDPGATCGKLRLYCCSGFCDSYT
    KTCKDKSSA-COOH
    NV1G1972 NV1D3824 361 GPGWCGDPGATCGKLRLYCCSGFCD
    AYTKTCKDKSSAGGGGSAPAPAPAP
    APAPAPAPAPAPAPAPAPAPAPGGG
    GSQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1946 NV1D3825 362 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGGGGSAPAPAPAPAPA
    PAPAPAPAPAPAPAPAPAPGGGGSG
    WCGDPGATCGKLRLYCCSGFCDAYT
    KTCKDKSSA-COOH
    NV1G1970 NV1D3826 363 GPCWCGDPGATCGKLRLYCCSGFCD
    CYTKTCKDKSSAGGGGSAPAPAPAP
    APAPAPAPAPAPAPAPAPAPAPGGG
    GSQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLW-COOH
    NV1G1949 NV1D3828 364 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGSGGGGSAPAPAPAPA
    PAPAPAPAPAPGGGGSGSCCNCSSK
    WCRDHSRCCGR-COOH
    NV1G1951 NV1D3829 365 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWGSGGGGSAPAPAPAPA
    PAPAPAPAPAPGGGGSGSCCNCSSK
    WCRDHSRCC-COOH
    NV1G1971 NV1D3830 366 GPCCNCSSKWCRDHSRCCGRGSGG
    GGSAPAPAPAPAPAPAPAPAPAPGG
    GGSGSQCQKWMQTCDRERKCCEGF
    VCTLWCRKKLW-COOH
    NV1G1975 NV1D3832 367 GPCRTIGPSVCAPAPAPAPAPAPAPA
    PAPAPQCQKWMQTCDRERKCCEGF
    VCTLWCRKKLW-COOH
    NV1G1978 NV1D3833 368 GPCRTIGPSVCAPAPAPAPAPQCQK
    WMQTCDRERKCCEGFVCTLWCRKK
    LW-COOH
    NV1G1979 NV1D3834 369 GPCRTIGPSVCAPAPAQCQKWMQT
    CDRERKCCEGFVCTLWCRKKLW-
    COOH
    NV1G2043 NV1D3835 370 GPCRTIGPSVCQCQKWMQTCDRER
    KCCEGFVCTLWCRKKLW-COOH
    NV1G1955 NV1D3838 371 GPQCQKWMQTCDRERKCCEGFVCT
    LWCRKKLWAPAPACRTIGPSVC-
    COOH
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the isolated Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 3×10−8 M or less.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the isolated Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of between about 3×10−8 M to about 1×10−9 M.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the amino acid sequence
  • (SEQ ID NO: 433)
    GPQCX1X2WX3QX4CX5X6X7X8X9CCX10
    X11FX12CX13LWCX14KKLL,

    wherein
  • X1 is Q, R, K, A or S;
  • X2 is K, S, Q or R;
  • X3 is M or F;
  • X4 is T, S, R, K or Q;
  • X5 is D or T;
  • X6 is S, A or R;
  • X7 is E, R, N, K, T or Q;
  • X8 is R or K;
  • X9 is K, Q, S or A;
  • X10 is E, Q or D;
  • X11 is G or Q;
  • X12 is V or S;
  • X13 is R or T; and
  • X14 is K or R.
  • Exemplary Protoxin-II variants that inhibit human Nav1.7 activity with an IC50 value of about 30×10−9 M or less are variants comprising the amino acid sequences of SEQ ID NOs: 56, 78, 111, 114, 117, 118, 119, 122, 123, 129, 130, 131, 132, 133, 134, 135, 136, 138, 139, 140, 141, 142, 145, 146, 147, 149, 150, 151, 152, 153, 154, 156, 158, 159, 165, 172, 173, 175, 177, 178, 183, 184, 185, 186, 189, 190, 193, 197, 199, 207, 210, 211, 216, 217, 224, 266, 273, 282, 335, 408, 409, 410, 422, 424, 425, 426, 427 and 428.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the isolated Protoxin-II variant selectively inhibits human Nav1.7. The Protoxin-II variants of the invention may be more selective towards Nav1.7 when compared to the recombinant Protoxin-II (SEQ ID NO: 2). In the QPatch electrophysiology assay, recombinant Protoxin-II has an IC50 of about 2.2×10−9 M for Nav1.7 and an IC50 of about 62×10−9 M for Nav1.6, and therefore the ratio of IC50 for Nav1.6 to IC50 for Nav1.7 is about 28 fold. “Selectivity” or “selective” or “more selective” or “selectively blocks” or “selectively inhibits” when used herein refers to a Protoxin-II variant that has a ratio of IC50 for Nav1.6 to IC50 for Nav1.7 (1C50(Nav1.6)/IC50(Nav1.7)) equal or over about 30. IC50 for Nav1.6 may be assayed in a QPatch electrophysiology assay using cell lines stably expressing Nav1.6 using similar methods to those described for Nav1.7.
  • Residue positions in Protoxin-II that can be mutagenized to improve selectivity include residues 7, 11, 12, 14, 17, 18 and 19, and optionally residues 1, 20, 22 and 26 (residue numbering according to SEQ ID NO: 1). Exemplary substitutions to improve selectivity are Y1Q, W7Q, S11R, S11A, E12T, M19F, V20S, R22T, and K26R. Exemplary Protoxin-II variants with improved selectivity are variants of SEQ ID NOs: 56, 59, 65, 78, 111, 114, 117, 118, 119, 121, 122, 123, 129, 130, 133, 150, 190, 217, 281, 324, 325 or 326.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the sequence
  • (SEQ ID NO: 405)
    GPX1CQKWMQX2CDX3X4RKCCX5GFX6CX7LWCX8KKLW;

    wherein
  • X1 is Y, Q, A, S or R;
  • X2 is T or S;
  • X3 is S, R or A;
  • X4 is E, T or N;
  • X5 is E or Q;
  • X6 is V or S;
  • X7 is R or T; and
  • X8 is K or R,
  • wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 3×10−8 M or less, and selectively inhibits human Nav1.7.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the isolated Protoxin-II variant comprises the sequence
  • (SEQ ID NO: 406)
    GPQCQKWMQX1CDX2X3RKCCX4GFX5CX6LWCX8KKLW;

    wherein
  • X1 is T or S;
  • X2 is S, R or A;
  • X3 is E, T or N;
  • X4 is E or Q;
  • X5 is V or S;
  • X6 is R or T; and
  • X7 is K or R.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 422 (GPYCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH); wherein
    • the amino acid sequence has Q at position 7 and L at position 30, when residue numbering is according to SEQ ID NO: 1; and
    • the polypeptide inhibits human Nav1.7 activity.
  • Protoxin-II variants having substitutions W7Q and W30L have improved folding, yield and selectivity when compared to the wild type Protoxin-II.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 78 (GPQCQKWMQTCDRERKCCEGFVCTLWCRKKLW-COOH); wherein
    • the amino acid sequence has Q at position 1, Q at position 7 and F at position 19, when residue numbering is according to SEQ ID NO: 1;
    • the polypeptide inhibits human Nav1.7 activity with an IC50 value of about 30×10−9 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7;
    • and the polypeptide selectively inhibits Nav1.7.
  • In some embodiments disclosed herein, including in the numbered embodiments listed below, the isolated Protoxin-II variant has a carboxylic acid, amide, methylamide or butylamide group at the C-terminus. C-terminal modifications may be generated via routine synthetic methods.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated fusion protein comprising the Protoxin-II variant of SEQ ID NOs: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 224, 226, 227, 232, 243, 244, 245, 247, 249, 252, 255, 258, 261, 263, 264, 265, 266, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 332, 334, 335, 336, 338, 339, 340, 341, 342, 346, 351, 358, 359, 364, 366, 367, 368, 369, 370, 371, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 434, 435, 436, 437, 438, 439, 440, 441, 442, 443, 444, 445, 446, 447, 448, 449, 450, 451, 452, 453, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463, 464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 475, 476, 477, 478, 479, 480, 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 404, 495, 496, 497, 498, 499, 500, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541, 542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554, 555, 556, 557, 558, 559, 560, 561, 562, 563, 564, 565, 566, 567, 568, 569, 570, 571, 572, 573, 574, 575, 576, 577, 578, 579, 580, 581, 582, 583, 584, 585, 586, 587, 588, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642, 643, 644, 645, 646, 647, 648, 649, 650, 651, 652, 653, 654, 655, 656, 657, 658, 659, 660, 661, 662, 663, 664, 665, 666, 667, 668, 669, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 690, 691, 692, 693, 694, 695, 696, 697, 698, 699, 700, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, 714, 715, 716, 717, 718, 719, 720, 721, 722, 723, 724, 725, 726, 727, 728, 729, 730, 731, 732, 733, 734, 735 or 736. Such second polypeptides may be well known leader or secretory signal sequences, or synthetic sequences resulting for example from cloning steps, or tags such as hexahistidine tag (SEQ ID NO: 108). Such second polypeptide may be a half-life extending moiety. In one embodiment, the isolated fusion protein comprises the Protoxin-II variant of the invention conjugated to a half-life extending moiety.
  • Exemplary half-life extending moieties that may be used include well known human serum albumin, transthyretin (TTR), a thyroxine-binding globulin (TGB), albumin-binding domains, or an Fc or fragments thereof. Biologically suitable polymers or copolymers may also be used, for example ethylene glycol or polyethylene glycol (PEG) molecules, such as PEG5000 or PEG20000, dextran, polylysine, fatty acids and fatty acid esters of different chain lengths, for example laurate, myristate, stearate, arachidate, behenate, oleate, arachidonate, octanedioic acid, tetradecanedioic acid, octadecanedioic acid, docosanedioic acid, and the like, octane, or carbohydrates (dextran, cellulose, oligo- or polysaccharides). Exemplary moieties that can improve biodistribution include polyamination (putrescine, spermine, or spermidine etc.), halogenation (chlorine, bromine, fluorine, iodine), and glycosylation. These moieties may be direct fusions with the Protoxin-II variant polypeptides and may be generated by standard cloning and expression techniques. Alternatively, well known chemical coupling methods may be used to attach the moieties to recombinantly produced Protoxin-II variants of the invention. Alternatively, moieties can be incorporated as non-coded amino acids during solid phase peptide synthesis.
  • In another embodiment of the invention disclosed herein, including in the numbered embodiments listed below, the half-life extending moiety of the fusion protein of the invention is human serum albumin, variants of human serum albumin, albumin binding domain (ABD), or polyethylene glycol (PEG).
  • In another embodiment disclosed herein, including in the numbered embodiments listed below, the half-life extending moiety of is conjugated to the Protoxin-II variant via a linker. Suitable linkers are well known and include linkers having the sequence shown in SEQ ID NOs: 80 or 81.
  • Exemplary fusion proteins incorporating Protoxin-II variants of the invention are those having the polypeptide sequence of SEQ ID NOs: 83, 85, 87, 89, 91, 93, 95, 97, 99, 101 or 103.
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below incorporating additional moieties may be compared for functionality by several well-known assays. For example, pharmacokinetic properties of Protoxin-II variants coupled to PEG may be evaluated in well known in vivo models.
  • Additional Protoxin-II variants and Protoxin-II variant fusion proteins are within the scope of the invention. Additional substitutions to the Protoxin-II variants of the invention can be made as long as the resulting variant or the fusion protein retains similar characteristics when compared to the parent peptide. Exemplary modifications are for example conservative substitutions that will result in Protoxin-II variants with similar characteristics to those of the parent molecules. Conservative replacements are those that take place within a family of amino acids that are related in their side chains. Genetically encoded amino acids can be divided into four families: (1) acidic (aspartate, glutamate); (2) basic (lysine, arginine, histidine); (3) nonpolar (alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan); and (4) uncharged polar (glycine, asparagine, glutamine, cysteine, serine, threonine, tyrosine). Phenylalanine, tryptophan, and tyrosine are sometimes classified jointly as aromatic amino acids. Alternatively, the amino acid repertoire can be grouped as (1) acidic (aspartate, glutamate); (2) basic (lysine, arginine histidine), (3) aliphatic (glycine, alanine, valine, leucine, isoleucine, serine, threonine), with serine and threonine optionally grouped separately as aliphatic-hydroxyl; (4) aromatic (phenylalanine, tyrosine, tryptophan); (5) amide (asparagine, glutamine); and (6) sulfur-containing (cysteine and methionine) (Stryer (ed.), Biochemistry, 2nd ed, WH Freeman and Co., 1981). Non-conservative substitutions can be made to the Protoxin-II variants that involve substitutions of amino acid residues between different classes of amino acids to improve properties of the Protoxin-II variants and Protoxin-II variant fusion proteins. Whether a change in the amino acid sequence of a polypeptide or fragment thereof results in a functional homolog can be readily determined by assessing the ability of the modified polypeptide or fragment to produce a response in a fashion similar to the unmodified polypeptide or fragment using the assays described herein. Peptides, polypeptides or proteins in which more than one replacement takes place can readily be tested in the same manner.
  • Another embodiment of the invention is an isolated family 3 spider venom cysteine knot peptide comprising at least one substitution at a position corresponding to position W7 and/or W30 of SEQ ID NO: 1. Family 3 spider toxins include 14 toxins with conserved C-terminal region, including, in addition to Protoxin-II, κ-TRTX-Gr2b, κ-TRTX-Gr2c, κ-TRTX-Ps1a, κ-TRTX-Ps1b, β-TRIX-Gr1b, κ-TRTX-Cj2a, κ-TRIX-Cj2b, κ-TRTX-Ec2c, β-TRIX-Gr1a, κ-TRTX-Ec2b, κ-TRTX-Ec2a and β/κ-TRTX-Cj2a and those shown in FIG. 14. Substitutions at positions W7 and/or W30 are expected to improve folding of the family 3 spider venom cysteine knot peptides.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is an isolated synthetic polynucleotide comprising a polynucleotide encoding the Protoxin-II variant of the invention.
  • Certain exemplary synthetic polynucleotides are disclosed herein, however, other synthetic polynucleotides which, given the degeneracy of the genetic code or codon preferences in a given expression system, encode the Protoxin-II variants and Protoxin-II variant fusion proteins of the invention are also within the scope of the invention. Exemplary synthetic polynucleotides are for example polynucleotide sequences shown in SEQ ID NOs: 84, 86, 88, 90, 92, 94, 96, 98, 100, 102 and 104, which encode the ProtoxinII variant fusion proteins of the invention. Those skilled in the art can readily identify the polynucleotide segments in the fusion proteins that encode the Protoxin-II variant itself. The synthetic polynucleotide sequences encoding the Protoxin-II variants or fusion proteins of the invention can be operably linked to one or more regulatory elements, such as a promoter and enhancer, that allow expression of the nucleotide sequence in the intended host cell. The synthetic polynucleotide may be a cDNA.
  • The polynucleotides of the invention may be produced by chemical synthesis such as solid phase polynucleotide synthesis on an automated polynucleotide synthesizer. Alternatively, the polynucleotides of the invention may be produced by other techniques such as PCR based duplication, vector based duplication, or restriction enzyme based DNA manipulation techniques. Techniques for producing or obtaining polynucleotides of known sequences are well known.
  • The polynucleotides of the invention may also comprise at least one non-coding sequence, such as transcribed but not translated sequences, termination signals, ribosome binding sites, mRNA stabilizing sequences, introns and polyadenylation signals. The polynucleotide sequences may also comprise additional sequences encoding additional amino acids. These additional polynucleotide sequences may, for example, encode a marker or well-known tag sequences such as a hexa-histidine (SEQ ID NO: 108) or a HA tag which facilitate the purification of fused polypeptides.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is a vector comprising the polynucleotide of the invention. Such vectors may be plasmid vectors, viral vectors, vectors for baculovirus expression, transposon based vectors or any other vector suitable for introduction of the polynucleotide of the invention into a given organism or genetic background by any means. For example, polynucleotides encoding the Protoxin-II variants or the Protoxin-II variant fusion proteins of the invention are inserted into an expression vector and may be operably linked to control sequences in the expression vector to ensure efficient expression, such as signal sequences, promoters (e.g. naturally associated or heterologous promoters), enhancer elements, and transcription termination sequences, and are chosen to be compatible with the host cell chosen to express the Protoxin-II variant or the Protoxin-II variant fusion protein of the invention. Once the vector has been incorporated into the appropriate host, the host is maintained under conditions suitable for high level expression of the proteins encoded by the incorporated polynucleotides.
  • Suitable expression vectors are typically replicable in the host organisms either as episomes or as an integral part of the host chromosomal DNA. Commonly, expression vectors contain selection markers such as ampicillin-resistance, hygromycin-resistance, tetracycline resistance, kanamycin resistance or neomycin resistance to permit detection of those cells transformed with the desired DNA sequences.
  • Suitable promoter and enhancer elements are known in the art. For expression in a bacterial cell, suitable promoters include, but are not limited to, lacl, lacZ, T3, T7, gpt, lambda P and trc. For expression in a eukaryotic cell, suitable promoters include, but are not limited to, light and/or heavy chain immunoglobulin gene promoter and enhancer elements; cytomegalovirus immediate early promoter; herpes simplex virus thymidine kinase promoter; early and late SV40 promoters; promoter present in long terminal repeats from a retrovirus; mouse metallothionein-I promoter; and various art-known tissue specific promoters. For expression in a yeast cell, a suitable promoter is a constitutive promoter such as an ADH1 PGK1, ENO or PYK1 promoter and the like, or a regulatable promoter such as a GALL or GAL10 promoter. Selection of the appropriate vector and promoter is well within the level of ordinary skill in the art.
  • Large numbers of suitable vectors and promoters are known to those of skill in the art; many are commercially available for generating recombinant constructs. The following vectors are provided by way of example. Bacterial: pBs, phagescript, PsiX174, pBluescript SK, pBs KS, pNH8a, pNH16a, pNH18a, pNH46a (Stratagene, La Jolla, Calif., USA); pTrc99A, pKK223-3, pKK233-3, pDR540, and pRIT5 (Pharmacia, Uppsala, Sweden). Eukaryotic: pWLneo, pSV2cat, pOG44, PXR1, pSG (Stratagene) pSVK3, pBPV, pMSG and pSVL (Pharmacia).
  • An exemplary vector for expression of the Protoxin-II variants or Protoxin-II variant fusion proteins is a vector having ampicillin-resistance selection marker, CMV promoter, CMV intron, signal peptide, neomycin resistance, f1 origin of replication, SV40 polyadenylation signal, and cDNA encoding the Protoxin-II variant or the Protoxin-II variant fusion protein of the invention.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is a host cell comprising the vector of the invention. The term “host cell” refers to a cell into which a vector has been introduced. It is understood that the term host cell is intended to refer not only to the particular subject cell but also to the progeny of such a cell. Because certain modifications may occur in succeeding generations due to either mutation or environmental influences, such progeny may not be identical to the parent cell, but are still included within the scope of the term “host cell” as used herein. Such host cells may be eukaryotic cells, prokaryotic cells, plant cells or archaeal cells.
  • Escherichia coli, bacilli, such as Bacillus subtilis, and other enterobacteriaceae, such as Salmonella, Serratia, and various Pseudomonas species, are examples of prokaryotic host cells. Other microbes, such as yeast, are also useful for expression. Saccharomyces (e.g., S. cerevisiae) and Pichia are examples of suitable yeast host cells. Exemplary eukaryotic cells may be of mammalian, insect, avian or other animal origins. Mammalian eukaryotic cells include immortalized cell lines such as hybridomas or myeloma cell lines such as SP2/0 (American Type Culture Collection (ATCC), Manassas, Va., CRL-1581), NSO (European Collection of Cell Cultures (ECACC), Salisbury, Wiltshire, UK, ECACC No. 85110503), FO (ATCC CRL-1646) and Ag653 (ATCC CRL-1580) murine cell lines. An exemplary human myeloma cell line is U266 (ATTC CRL-TIB-196). Other useful cell lines include those derived from Chinese Hamster Ovary (CHO) cells such as CHO-K1SV (Lonza Biologics, Walkersville, Md.), CHO-K1 (ATCC CRL-61) or DG44.
  • Introduction of a polynucleotide, such as a vector, into a host cell can be effected by methods well known to those skilled in the art. Exemplary methods are calcium phosphate transfection, DEAE-Dextran mediated transfection, microinjection, cationic lipid-mediated transfection and electroporation.
  • Another embodiment of the invention disclosed herein, including in the numbered embodiments listed below is a method for producing the Protoxin-II variant of the invention comprising the steps of providing a host cell of the invention; and culturing the host cell under conditions sufficient for the expression of at least one Protoxin-II variant of the invention.
  • Host cells can be cultured under any conditions suitable for maintaining or propagating a given type of host cell and sufficient for expressing a polypeptide. Culture conditions, media, and related methods sufficient for the expression of polypeptides are well known in the art. For example, many mammalian cell types can be aerobically cultured at 37° C. using appropriately buffered DMEM media while bacterial, yeast and other cell types may be cultured at 37° C. under appropriate atmospheric conditions in LB media.
  • In the methods of the invention disclosed herein, including in the numbered embodiments listed below, the expression of the Protoxin-II variant can be confirmed using a variety of well-known methods. For example, expression of a polypeptide can be confirmed using detection reagents, such as using SDS-PAGE or HPLC.
  • Another aspect of the invention is a method of modulating the activity of Nav1.7 in a biological tissue, the method comprising contacting the biological tissue expressing Nav1.7 with a Nav1.7-modulating amount of the Protoxin-II variant of the invention.
  • Methods of Treatment
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be utilized in any therapy where it is desired to treat, reduce or alleviate symptoms of pain or other disorders of sensory or sympathetic neuron dysfunction.
  • Pain treated with the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be any type of pain, such as chronic pain, acute pain, neuropathic pain, nociceptive pain, visceral pain, back pain, pain associated with inflammatory conditions, post-operative pain, thermal pain or pain associated with disease and degeneration.
  • Pain treated with the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be Nav1.7-mediated pain.
  • Nav1.7-mediated pain as used herein refers to pain resulting at least partially from increased Nav1.7 channel activity.
  • The methods of the invention may be used to treat an animal patient belonging to any classification. Examples of such animals include mammals such as humans, rodents, dogs, cats and farm animals.
  • The pain and/or Nav1.7-mediated pain may result from one or more causes, such as peripheral neuropathy, central neuropathy, nerve compression or entrapment syndromes such as carpal tunnel syndrome, tarsus tunnel syndrome, ulnar nerve entrapment, compression radiculopathy, lumbar spinal stenosis, sciatic nerve compression, spinal root compression, intercostal neuralgia, compression radiculopathy and radicular lower back pain, spinal root lesions, neuritis, autoimmune diseases, general inflammation, chronic inflammatory conditions, arthritis, rheumatic diseases, lupus, osteoarthritis, general gastrointestinal disorders, colitis, gastric ulceration, duodenal ulcers, inflammatory bowel disorders, irritable bowel syndrome, pain associated with diarrhea, inflammatory eye disorders, inflammatory or unstable bladder disorders, psoriasis, skin complaints with inflammatory components, sunburn, carditis, dermatitis, myositis, neuritis, collagen vascular diseases, inflammatory pain and associated hyperalgesia and allodynia, neuropathic pain and associated hyperalgesia and allodynia, multiple sclerosis, demyelinating diseases, diabetes, diabetic neuropathy pain, causalgia, pain resulting from amputation or abscess, phantom limb pain, fracture pain, bone injury, direct trauma, HIV infection, acquired immune deficiency syndrome (“AIDS”), smallpox infection, herpes infection, exposure to toxins or other foreign particles or molecules, invasive cancer, cancer, chemotherapy, radiotherapy, hormonal therapy, burns, congenital defect, dental pain, gout pain, fibromyalgias, encephalitis, chronic alcoholism, hypothyroidism, uremia and vitamin deficiencies, trigeminal neuralgia, stroke, thalamic pain syndrome, general headache, migraine, cluster headache, tension headache, mixed-vascular and non-vascular syndromes, sympathetically maintained pain, deafferentation syndromes, asthma, epithelial tissue damage or dysfunction, disturbances of visceral motility at respiratory, genitourinary, gastrointestinal or vascular regions, wounds, burns, allergic skin reactions, pruritis, vasomotor or allergic rhinitis, or bronchial disorders, dysmenorrhoea, pain during labor and delivery, dyspepsia, gastroesophageal reflux, pancreatitis, and visceralgia.
  • Other disorders of sensory or sympathetic neuron dysfunction that may be alleviated by the Protoxin-II variants of the invention include itch, cough and asthma. In mice, global deletion of the SCN9A gene leads to complete insensitivity to histamine-induced itch (Gingras et al., American Pain Society Meeting Abstract 2013 and U.S. Pat. Publ. No. 2012/0185956). This finding suggests that peptide Nav1.7 blockers may have utility in the treatment of itch, which may arise from various sources, such as dermatological or inflammatory disorders; or inflammatory disorders such as renal or hepatobiliary disorders, immunological disorders, medication reactions and unknown/idiopathic conditions, including dermatitis, psoriasis, eczema, insect sting or bite. Nav1.7 is also expressed in sensory nerves innervating the airways (Muroi et al., J Physiol. 2011 Dec. 1; 589(Pt 23):5663-76; Muroi et al., Am J Physiol Regul Integr Comp Physiol. 2013 Apr. 10), suggesting that peptide Nav1.7 blockers may be beneficial in the treatment of cough e.g., acute or chronic cough, or cough caused by irritation from gastroesophageal reflux disease, and inflammatory diseases of the airways such as asthma and allergy-related immune responses, bronchospasm, chronic obstructive pulmonary disease, chronic bronchitis, emphysema, and hiccups (hiccoughs, singultus). Silencing Nav1.7 in vivo in nodose ganglia of guinea pigs using shRNA nearly abolished the cough reflex induced by mechanical probing (Muroi et al., Am J Physiol Regul Integr Comp Physiol. 2013 Apr 10).
  • One aspect of the invention is a method of alleviating or treating itch, cough or asthma in a subject by administering a therapeutically effective amount of the Protoxin-II variant of the invention disclosed herein, including in the numbered embodiments listed below to a subject in need thereof for a time sufficient to alleviate the itch, cough or asthma.
  • Another aspect of the invention is a method of alleviating or treating Nav1.7-mediated itch, Nav1.7-mediated cough or Nav1.7-mediated asthma in a subject by administering a therapeutically effective amount of the Protoxin-II variant of the invention disclosed herein, including in the numbered embodiments listed below to a subject in need thereof for a time sufficient to alleviate the itch, cough or asthma.
  • Nav1.7-mediated itch as used herein refers to itch resulting at least partially from increased Nav1.7 channel activity.
  • Nav1.7-mediated cough as used herein refers to cough resulting at least partially from increased Nav1.7 channel activity.
  • Nav1.7-mediated asthma as used herein refers to asthma resulting at least partially from increased Nav1.7 channel activity.
  • Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be tested for their effect in reducing or alleviating pain and/or Nav1.7-mediated pain using animal models described herein, and models such as the rat spinal nerve ligation (SNL) model of neuropathic pain, carageenan induced allodynia model, the Freund's complete adjuvant (CFA)-induced allodynia model, the thermal injury model, the formalin model and the Bennett Model, and other models as described in U.S. Pat. Appl. No. 2011/0124711 and U.S. Pat. No. 7,998,980. Carageenan induced allodynia and CFA-induced allodynia are models of inflammatory pain. The Bennett model provides an animal model for chronic pain including post-operative pain, complex regional pain syndrome, and reflex sympathetic dystrophy.
  • Any of the foregoing animal models may be used to evaluate the efficacy of Protoxin-II variants of the invention inhibitor in treating pain and/or NAv1.7-mediated pain. The efficacy of the Protoxin-II variants of the invention may be compared to a no treatment or placebo control. Additionally or alternatively, efficacy may be evaluated in comparison to one or more known pain-relieving medicaments.
  • The present invention provides methods of treating Nav1.7-mediated pain using the Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below. It has been discovered in the pending application by the inventors (U.S. Patent Application No. 61/781,276) that administration of Nav1.7 blocking peptides are efficacious in treating and/or alleviating pain in various animal models of pain, contrary to what was disclosed and suggested in the literature. While peptide inhibitors of Nav1.7 have been shown to be potent and/or selective towards Nav1.7 in in vitro cell culture models using overexpressed Nav1.7 or on isolated neurons in which the blood-nerve barrier is subverted through desheathing or hypertonic saline injection, they have so far proven non-efficacious in in vivo animal models of pain, where the lack of efficacy has been reported to result from the inability of the peptides to pass the blood-nerve barrier. Several publications describe lack of efficacy of Nav1.7 blocking peptides in animal models of pain or in isolated nerves. For example Hackel et al., Proc Natl Acad Sci 109:E2018-27, 2012, describes the inability of ProTx-II to inhibit action potential firing in isolated nerves unless the perineural barrier, which provides a diffusion barrier in this model, is compromised. ProTx-II was found non-efficacious in rodent models of acute and inflammatory pain; a likely explanation stated the inability of ProTx-II to cross the blood-nerve barrier (Schmalhofer et al., Mol Pharmacol 74:1476-1484, 2008). It has been proposed that Nav1.7 peptide toxin blockers have poor oral bioavailability and they are difficult to deliver to nerve endings, implying that their use as therapeutic agents remain limited (Dib-Hajj et al., Nature Rev Neuroscience 14, 49-62, 2013).
  • Nav1.7 is expressed in the peripheral nervous system e.g., in nociceptive dorsal root ganglions (DRG), most notably in nociceptive small-diameter DRG neurons, in particular in peripheral terminals in the skin, with little representation in the brain. Nav1.7 distribution (e.g. sensory ending) and physiology predispose it to a major role in transmitting painful stimuli.
  • One embodiment of the invention is a method of treating Nav1.7-mediated pain by administering a therapeutically effective amount of the Protoxin-II variant of the invention disclosed herein, including in the numbered embodiments listed below to a subject in need thereof for a time sufficient to treat the Nav1.7-mediated pain.
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be utilized in any therapy where it is desired to treat Nav1.7-mediated pain or other disorders of sensory or sympathetic neuron dysfunction. “Treat” or “treatment” of pain is meant to include partially or completely to prevent, stop, inhibit, reduce, or delay the perception of pain.
  • In some embodiments, the Nav1.7-mediated pain is chronic pain, acute pain, neuropathic pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis, or pain associated with disease and degeneration.
  • Neuropathic pain includes for example painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN) or trigeminal neuralgia (TN). Other causes of neuropathic pain include spinal cord injuries, multiple sclerosis, phantom limb pain, post-stroke pain and HIV-associated pain. Conditions such as chronic back pain, osteoarthritis and cancer may also result in the generation of neuropathic-related pain and thus are potentially suitable for treatment with the Protoxin-II variants of the invention.
  • In another embodiment, the Nav1.7-mediated pain is associated with primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis or fibromyalgia.
  • In the methods of the invention, the Protoxin-II variants of the invention may be conjugated to a second polypeptide to form a fusion protein. Such fusion proteins are for example the well-known Fc fusions or fusions to human serum albumin to extend half-life of the peptide inhibitors. The conjugation may be a direct conjugation via a linker, such as a glycine-serine rich linker. Such linkers are well known in the art. The Protoxin-II variants of the invention incorporating additional moieties may be compared for their Nav1.7 blocking ability and efficacy in treatment or reducing pain using well known methods and those described herein.
  • Other disorders of sensory or sympathetic neuron dysfunction that can be treated with the Protoxin-II variants of the invention, including asthma, cough, heartburn, itch, dermatitis, bladder instability, and Reynaud's disease.
  • Pharmaceutical Compositions
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be formulated in a pharmaceutically acceptable vehicle or carrier. One embodiment of the invention is a pharmaceutical composition comprising the isolated Protoxin-II variant of the invention and a pharmaceutically acceptable excipient.
  • A suitable vehicle or carrier may be water for injection, physiological saline solution or artificial cerebrospinal fluid, possibly supplemented with other materials common in compositions for parenteral administration. Neutral buffered saline or saline mixed with serum albumin are further exemplary vehicles. These solutions are sterile and generally free of particulate matter, and may be sterilized by conventional, well-known sterilization techniques (e.g., filtration). The compositions may contain pharmaceutically acceptable excipients as required to approximate physiological conditions, such as pH adjusting and buffering agents, stabilizing, thickening, lubricating and coloring agents, etc. Suitable vehicles and their formulation and packaging are described, for example, in Remington: The Science and Practice of Pharmacy (21st ed., Troy, D. ed., Lippincott Williams & Wilkins, Baltimore, Md. (2005) Chapters 40 and 41).
  • In the methods of the invention, the Protoxin-II variants of the invention may be administered by peripheral administration. “Peripheral administration” or “administered peripherally” means introducing an agent into a subject outside of the central nervous system. Peripheral administration encompasses any route of administration other than direct administration to the spine or brain.
  • Peripheral administration can be local or systemic. Local administration may be used to concentrate the therapeutic to the site of action, such as local administration to joints, surgical wounds, sites of injury/trauma, peripheral nerve fibers, various organs (GI, urogenital, etc.) or inflamed tissues. Systemic administration results in delivery of a pharmaceutical composition to essentially the entire peripheral nervous system of the subject and may also result in delivery to the central nervous system depending on the properties of the composition.
  • Routes of peripheral administration encompass, without limitation, topical administration, intravenous, subcutaneous, intra-muscular, intra-articular or other injection, and implanted mini-pumps or other extended release devices or formulations.
  • Compounds may also be administered directly to the central nervous system e.g., intrathecal or intracisternal administration. Continuous intrathecal administration can be achieved via the use of implanted spinal drug pumps.
  • Pharmaceutical compositions of the invention include formulations involving the Protoxin-II variants of the invention in sustained- or controlled-delivery formulations. These formulations may be achieved through use of for example injectable microspheres, bio-erodible particles, microemulsions, nanoparticles, nanocapsules, macroemulsions, polymeric compounds (such as polyesters, polyamino acids, hydrogels, poly(lactic acid), polyglycolic acid or ethylene vinylacetate copolymers), beads or liposomes, hyaluronic acid or implantable drug delivery devices.
  • The Protoxin-II variants of the invention disclosed herein, including in the numbered embodiments listed below may be prepared for use for parenteral (subcutaneous, intramuscular or intravenous), intracerebral (intraparenchymal), intrathecal, intra-articular, intracerebroventricular, intramuscular, intra-ocular, intra-arterial, intraportal, or intralesional routes; by sustained release systems or by implantation devices, or any other administration, particularly in the form of liquid solutions or suspensions; for buccal or sublingual administration such as in the form of tablets or capsules; or intranasally such as in form of powders, nasal drops or aerosols or certain agents; transdermally in a form of a gel, ointment, lotion, cream or dusting powder, suspension or patch delivery system with chemical enhancers to either modify the skin structure or to increase the drug concentration in the transdermal patch, or with agents that enable the application of formulations containing proteins and peptides onto the skin (Int. Pat. Publ. No. W098/53847), or applications of electric fields to create transient transport pathways such as electroporation, or to increase the mobility of charged drugs through the skin such as iontophoresis, or application of ultrasound such as sonophoresis (U.S. Pat. Nos. 4,309,989 and 4,767,402). The composition also may be administered locally via implantation of a membrane, sponge or another appropriate material onto which the desired molecule has been absorbed or encapsulated.
  • In certain embodiments, where an implantation device is used, the device may be implanted into any suitable tissue or organ, and delivery of the desired molecule may be via diffusion, timed-release bolus, or continuous administration.
  • The concentration of the Protoxin-II variants of the invention or other peptide inhibitors of Nav1.7 in such pharmaceutical formulation can vary widely, for example from about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2% or between 2% to 5%, up to as much as 15%, 20%, 30%, 40%, 50%, 60% or 70% by weight and will be selected primarily based on fluid volumes, viscosities and other factors, according to the particular mode of administration selected. The Protoxin-II variants of the invention can be lyophilized for storage and reconstituted in a suitable vehicle prior to use. This technique has been shown to be effective with conventional protein preparations. Lyophilization and reconstitution techniques are well known in the art.
  • An exemplary pharmaceutical composition of the present invention may comprise Tris buffer of about pH 7.0-8.5, or acetate buffer of about pH 4.0-5.5, and may further include sorbitol, sucrose, Tween-20 and/or a suitable substitute thereof.
  • The appropriate therapeutically effective amount may be determined readily by those skilled in the art. A therapeutically effective amount refers to an amount or dosage sufficient to produce a desired result, i.e. to partially or completely prevent, stop, inhibit, reduce, or delay the perception of pain associated with any painful medical condition. The therapeutically effective amount may vary depending on the specific vehicle and the Protoxin-II variants of the invention selected, and is also dependent on a variety of factors and conditions related to the subject to be treated and the severity of the pain. For example, factors such as age, weight and health of the subject to be administered with the pharmaceutical compositions of the invention as well as dose response curves and toxicity data obtained in preclinical animal work could be among those considered. A determined dose may, if necessary, be repeated at appropriate time intervals selected as appropriate by a physician or other person skilled in the relevant art (e.g. nurse, veterinarian, or veterinary technician) during the treatment period. The determination of an effective amount or a therapeutically effective amount for a given agent is well within the ability of those skilled in the art.
  • Thus, a pharmaceutical composition of the invention for intramuscular injection could be prepared to contain 1 ml sterile buffered water, and between about 1 ng to about 100 mg, about 50 ng to about 30 mg or about 5 mg to about 25 mg of a Protoxin-II variant of the invention. Similarly, a pharmaceutical composition of the invention for intravenous infusion could be made up to contain about 250 ml of sterile Ringer's solution, and about 1 mg to about 30 mg or about 5 mg to about 25 mg of the Protoxin-II variants of the invention. Actual methods for preparing parenterally administrable compositions are well known and are described in more detail in, for example, “Remington's Pharmaceutical Science”, 15th ed., Mack Publishing Company, Easton, Pa.
  • Further Embodiments of the Invention
  • Set out below are certain further embodiments of the invention according to the disclosures elsewhere herein. Features from embodiments of the invention set out above described as relating to the invention disclosed herein also relate to each and every one of these further numbered embodiments.
  • 1) An isolated Protoxin-II variant comprising the sequence
  • (SEQ ID NO: 403)
    X1X2X3CX4X5WX6QX7CX8X9X10X11X12CCX13X14FX15CX16LWC
    X17KKLW,

    wherein
  • X1 is G, P, A or deleted;
  • X2 is P, A or deleted;
  • X3 is S, Q, A, R or Y;
  • X4 is Q, R, K, A or S;
  • X5 is K, S, Q or R;
  • X6 is M or F;
  • X7 is T, S, R, K or Q;
  • X8 is D or T;
  • X9 is S, A or R;
  • X10 is E, R, N, K, T or Q;
  • X11 is R or K;
  • X12 is K, Q, S or A;
  • X13 is E, Q or D;
  • X14 is G or Q;
  • X15 is V or S;
  • X16 is R or T; and
  • X17 is K or R;
  • optionally having an N-terminal extension or a C-terminal extension, wherein the polypeptide inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
  • 2) The Protoxin-II variant of claim 1, wherein the N-terminal extension comprises the amino acid sequence of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
  • 3) The Protoxin-II variant of claim 1 or 2, wherein the C-terminal extension comprises the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
  • 4) The Protoxin-II variant of claim 2 or 3, wherein the N-terminal and/or the C-terminal extension is conjugated to the Protoxin-II variant via a linker.
  • 5) The Protoxin-II variant of claim 4, wherein the linker comprises the amino acid sequence of SEQ ID NOs: 383, 392, 398, 399, 400, 401 or 402.
  • 6) The isolated Protoxin-II variant of any of the claim 1-5, comprising the amino acid sequence of SEQ ID NOs: 30, 40, 44, 52, 56, 59, 65, 78, 109, 110, 111, 114, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 224, 226, 227, 232, 243, 244, 245, 247, 249, 252, 255, 258, 261, 263, 264, 265, 266, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 332, 334, 335, 336, 338, 339, 340, 341, 342, 346, 351, 358, 359, 364, 366, 367 or 368.
  • 7) The isolated Protoxin-II variant of any of the claims 1-6, that inhibits human Nav1.7 activity with an IC50 value of about 3×10−8 M or less.
  • 8) The isolated Protoxin-II variant of claim 7 that inhibits human Nav1.7 activity with an IC50 value of between about 3×10−8 M to about 1×10−9 M.
  • 9) The isolated Protoxin-II variant of claim 7 or 8 comprising the amino acid sequence
  • (SEQ ID NO: 404)
    GPQCX1X2WX3QX4CX5X6X7X8X9C
    CX10X11FX11FX12CX13LWCX14K
    KLW,

    wherein
  • X1 is Q, R, K, A, or S;
  • X2 is K, S, Q or R;
  • X3 is M or F;
  • X4 is T, S, R, K or Q;
  • X5 is D or T;
  • X6 is S, A or R;
  • X7 is E, R, N, K, T or Q;
  • X8 is R or K;
  • X9 is K, Q, S or A;
  • X10 is E, Q or D;
  • X11 is G or Q;
  • X12 is V or S;
  • X13 is R or T; and
  • X14 is K or R.
  • 10) The isolated Protoxin-II variant of claim 9, comprising the amino acid sequence of SEQ ID NOs: 56, 78, 111, 114, 117, 118, 119, 122, 123, 129, 130, 131, 132, 133, 134, 135, 136, 138, 139, 140, 141, 142, 145, 146, 147, 149, 150, 151, 152, 153, 154, 16, 158, 159, 165, 172, 173, 175, 177, 178, 183, 184, 185, 186, 189, 190, 193, 197, 199, 207, 210, 211, 216, 217, 224, 266, 273, 282 or 335.
  • 11) The isolated Protoxin-II variant of any of the claims 1-10, wherein the variant selectively inhibits human Nav1.7.
  • 12) The isolated Protoxin-II variant of claim 11, comprising the sequence
  • (SEQ ID NO: 405)
    GPX1CQKWMQX2CDX3X4RKCCX5
    GFX6CX7LWCX8KKLW;
  • X1 is Y, Q, A, S or R;
  • X2 is T or S;
  • X3 is S, R or A;
  • X4 is E, T or N;
  • X5 is E or Q;
  • X6 is V or S;
  • X7 is R or T; and
  • X8 is K or R.
  • 13) The isolated Protoxin-II variant of claim 12, comprising the amino acid sequence of SEQ ID NOs: 56, 59, 65, 78, 111, 114, 117, 118, 119, 121, 122, 123, 129, 130, 133, 150, 190, 217, 281, 324, 325 or 326.
  • 14) The isolated Protoxin-II variant of claim 12, comprising the sequence
  • (SEQ ID NO: 406)
    GPQCQKWMQX1CDX2X3RKCCX4
    GFX5CX6LWCX8KKLW;

    wherein
  • X1 is T or S;
  • X2 is S, R or A;
  • X3 is E, T or N;
  • X4 is E or Q;
  • X5 is V or S;
  • X6 is R or T; and
  • X7 is K or R.
  • 15) An isolated Protoxin-II variant comprising the amino acid sequence that is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 78 (GPQCQKWMQTCDRERKCCEGFVCTLWCRKKLW-COOH), wherein
  • a) the amino acid sequence has Q at position 1, Q at position 7 and F at position 19, when residue numbering is according to SEQ ID NO: 1;
  • b) the polypeptide inhibits human Nav1.7 activity with an IC50 value of about 30×10−9 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7; and
  • c) the polypeptide selectively inhibits Nav1.7.
  • 16) The isolated Protoxin-II variant of any of the claims 1-15, having a free C-terminal carboxylic acid, amide, methylamide or butylamide group.
  • 17) An isolated fusion protein comprising the Protoxin-II variant of any of the claims 1-16 conjugated to a half-life extending moiety.
  • 18) The fusion protein of claim 17, wherein the half-life extending moiety is human serum albumin (HSA), albumin binding domain (ABD), Fc or polyethylene glycol (PEG).
  • 19) An isolated polynucleotide encoding the Protoxin-II variant of claim 12 or 15.
  • 20) A vector comprising the isolated polynucleotide of claim 19.
  • 21) A host cell comprising the vector of claim 20.
  • 22) A method of producing the isolated Protoxin-II variant, comprising culturing the host cell of claim 21 and recovering the Protoxin-II variant produced by the host cell.
  • 23) A pharmaceutical composition comprising the isolated Protoxin-II variant of claim 1, 6, 12, 13 or 15 and a pharmaceutically acceptable excipient.
  • 24) A method of treating Nav1.7-mediated pain in a subject, comprising administering to a subject in need thereof an effective amount of the Protoxin-II variant of any of the claims 1-16 to treat the pain.
  • 25) The method of claim 24, wherein pain is chronic pain, acute pain, neuropathic pain, cancer pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis.
  • 26) The method of claim 24, wherein the Protoxin-II variant is administered peripherally.
  • 27) The method of claim 24, wherein the Protoxin-II variant is administered locally to a joint, spinal cord, surgical wound, sites of injury or trauma, peripheral nerve fibers, urogenital organs, or inflamed tissues.
  • 28) The method of claim 24, wherein the subject is a human.
  • 29) The Protoxin-II variant of any of the claims 1-16 for use in treating pain in a subject in need thereof.
  • 30) The Protoxin-II variant for use according to claim 29, wherein pain is chronic pain, acute pain, neuropathic pain, cancer pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis.
  • 31) The Protoxin-II variant for use according to claim 29 or 30, wherein the Protoxin-II variant is administered peripherally.
  • 32) The Protoxin-II variant for use according to claim 29, 30 or 31, wherein the Protoxin-II variant is administered locally to a joint, spinal cord, surgical wound, sites of injury or trauma, peripheral nerve fibers, urogenital organs, or inflamed tissues.
  • The present invention will now be described with reference to the following specific, non-limiting examples.
    • EXAMPLE 1 Design and Generation of Protoxin-II Variants
  • A Protoxin-II single position limited amino acid substitution scanning library was designed to assess to what degree selectivity, peptide yield, and homogeneity can be improved.
  • Protoxin-II variants were designed as HRV3C protease cleavable HSA fusion proteins in the following format from N- to C-terminus: 6× His-HSA-linker-HRV3C cleavable peptide Protoxin-II variant (“6× His” disclosed as SEQ ID NO: 108); linker being (GGGGSGGGGSGGGGSGGGGS; SEQ ID NO: 80, HSA having the sequence of SEQ ID NO: 106, HRV3C cleavable peptide having the sequence of SEQ ID NO: 82). Each Protoxin-II variant, after cleavage from HSA had a residual N-terminal GP from the cleavage site.
  • The variants were characterized in membrane depolarization assays using FLIPR® Tetra as described in Example 3 veratridine-induced depolarization inhibition assay, and in whole cell patch clamp experiments using the QPatch assay as described in Example 3.
  • Combinatorial libraries were designed to test for additive effects of select single position hits in an attempt to generate Nav1.7 antagonists with further improved potency and selectivity profile compared to the native peptide.
  • Construction of the Expression Vectors
  • The designed Protoxin-II variant genes were generated using synthetic gene assembly technology as described in U.S. Pat. No. 6,521,427. The amino acid sequences of the designed peptide variants were back-translated to DNA sequences using human high-frequency codons. The DNA sequence of each variant gene, together with a portion of vector DNA including the DNA cloning sites, was synthesized as multiple oligonucleotides, some of which contained degenerate codons, and assembled into full-length DNA fragments. The assembled DNA fragments were amplified by PCR and PCR products were subsequently cloned as a pool. Pooled PCR products were digested with the appropriate restriction enzymes and cloned into the designed expression vector in such a manner as to fuse each toxin variant gene to the signal peptide and the fusion partner (6× His-HSA-linker-HRV3C cleavable peptide (“6× His” disclosed as SEQ ID NO: 108) contained in the vector. Standard molecular biology techniques were used to identify a positive clone for each designed variant. The plasmid DNA from these positive clones was purified and sequence confirmed before expressing the Protoxin-II peptide variant fusion proteins using standard methods.
  • Protein Expression
  • HEK 293-F cells were maintained in 293 Freestyle™ media (Invitrogen Cat#12338) and split when the cell concentration was between 1.5 and 2.0×106 cells per ml. The cells were grown in suspension, shaking at 125 RPM in a humidified incubator set at 37° C. and 8% CO2. HEK 293F cells were transiently transfected using a DNA/lipid complex after they were diluted to 1.0×106 cells per ml. To generate the complex, 1.25 μg DNA per mL of transfection was diluted in 1.0 mL of OptiPro media (Invitrogen Cat#12309) and 1.25 ml of Freestyle™ Max transfection reagent (Invitrogen Cat#16447) was diluted in 1.0 mL of OptiPro media. The DNA and Max transfection reagent were mixed together and incubated for 10 minutes at room temperature before adding to the cells. Transfected cells were placed in a humidified incubator set at 37° C. and 8% CO2for 4 days shaking at 125 RPM. The supernatant was separated from the cells by centrifugation at 5,000×g for 10 minutes and filtered through a 0.2 μm filter (Corning; Cat#431153), then concentrated 10 and 50 fold using an Amicon Ultra Concentrator 10K (Cat#UFC901096), and centrifuging for approximately 10 minutes at 3,750×g.
    • EXAMPLE 2 Purification of Protoxin-II Variants
  • Protoxin-II variants were expressed as HSA fusion proteins as indicated in Example 1 and the Protoxin-II variant peptides were cleaved with HRV3C protease prior to purification. Two methodologies were tested for efficient purification of the Protoxin-II variants.
  • Protein Purification
  • Purification of Protoxin-II Variants by RP-HPLC
  • The secreted proteins were purified from the expression supernatants via IMAC using 1 ml HisTrap HP columns (GE Healthcare Cat#17-5247-01). The chromatography method was run using an AKTA Xpress and protein was eluted from the column using a step gradient of imidazole. Peak fractions were pooled and digested overnight with HRV 3C protease (1 μg protease/150 μg fusion).
  • Cleaved peptide-fusion pools were further purified using a Dionex HPLC system with a reverse phase Phenomenex Luna 5 pm C18(2) column (Cat#00B-4252-PO-AX). Samples were eluted from the column with a 0-68% acetonitrile (0.05% TFA) linear gradient. Elution fractions were pooled, lyophilized overnight and reconstituted in HEPES buffered saline, pH 7.4 (10 mM HEPES, 137 mM NaCl, 5.4 mM KCl, 5 mM glucose, 2 mM CaCl2, 1 mM MgCl2).
  • Table 4 shows yields of Protoxin-II variants purified by RP-HPLC. The average mg yield/L was 0.01615.
  • TABLE 4
    Protoxin-ll
    Variant
    Peptide ID yield (mg)
    NV1D816  0.0008
    NV1D2511 0.0009
    NV1D2513 0.0034
    NV1D2504 0.0071
    NV1D2260 0.0129
    NV1D2498 0.0079
    NV1D2499 0.0076
    NV1D2512 0.0061
    NV1D2267 0.0095
    NV1D2507 0.0000
    NV1D2509 0.0000
    NV1D2305 0.0001
    NV1D815  0.0021
    NV1D2506 0.0001
    NV1D2505 0.0006
    NV1D812  0.0001
    NV1D2510 0.0009
    NV1D769  0.0031
    NV1D2497 0.0038
    NV1D2500 0.0004
    NV1D767  0.0004
    NV1D2502 0.0002
    NV1D2496 0.0006
    NV1D2503 0.0030
    NV1D766  0.0054
    NV1D770  0.0040
    NV1D772  0.0015
    NV1D792  0.0016
    NV1D815  0.0008
    NV1D768  0.0060
    NV1D2508 0.0017
    NV1D2501 0.0008
    NV1D2296 0.0018
    NV1D2292 0.0059
    NV1D750  0.0023
    NV1D748  0.0036
    NV1D774  0.0050
    NV1D786  0.0036
    NV1D855  0.0008
    NV1D2312 0.0011
    NV1D1410 0.0074
    NV1D1415 0.0128
    NV1D751  0.0033
  • Purification of Protoxin-II Variants by Solid Phase Extraction (SPE)
  • The secreted proteins were purified from the expression supernatants via IMAC using 1 mL HisTrap HP columns (GE Healthcare Cat#17-5247-01). The chromatography method was run using an AKTA Xpress and protein was eluted from the column using a step gradient of Imidazole. Peak fractions were pooled and digested overnight with HRV3C protease (1 μg protease/150 μg fusion). The cleaved sample was loaded into a 50 kDa molecular weight cutoff centrifugal filter unit (Millipore UFC805096) and cleaved peptide collected in the filtrate fraction.
  • Peptide pools were loaded onto a 96-well solid phase extraction block (Agilent Bond Elut Plexa A3969030) for further purification, desalting, and concentration. Blocks were used in conjunction with a vacuum manifold (Whatman). Peptide samples were loaded and washed in 0.05% TFA in water and eluted with a step gradient of acetonitrile with 0.05% TFA in water. Elution fractions were then lyophilized overnight and reconstituted in HEPES buffered saline, pH 7.4 (10 mM HEPES, 137 mM NaCl, 5.4 mM KCl, 5 mM glucose, 2 mM CaCl2, 1 mM MgCl2)
  • Peptides were reconstituted in supplemented HEPES buffered saline, pH 7.4 (10 mM HEPES, 137 mM NaCl, 5.4 mM KCl, 5 mM glucose, 2 mM CaCl2, 1 mM MgCl2) and absorbance was measured at 280 nm. Concentration values were then calculated using each sample's extinction coefficient. 2 μg of each peptide were loaded onto an Invitrogen NuPAGE® Novex® Bis-Tris Gel 15 well gel and run in MES buffer non-reduced.
  • Samples were analyzed on Agilent 1100 HPLC using 4-80% acetonitrile in 0.05% TFA linear gradient with a Phenomenex Luna C18(2) analytical column (Cat#00A-4041-B0). Concentrations of all peptides were normalized and 10 μL of each were injected for a total of 1.3 μg per sample. Absorbance at 220 nm was monitored and chromatograms analyzed were using Chromeleon software.
  • Table 5 shows yields (mg) of Protoxin-II variants purified by SPE. The average mg yield/L was 0.05353.
  • The benefits of the SPE purification process are ease and throughput of purification since samples are processed in parallel in a 96-well block rather than serially on RP-HPLC, and improvement in yield. There was, on average, more than 3-fold higher yield (mg/L) for variants purified by SPE versus RP-HPLC.
  • TABLE 5
    Protoxin-ll
    Variant
    Peptide ID yield (mg)
    NV1D12  0.0054
    NV1D2659 0.0234
    NV1D2664 0.0060
    NV1D2666 0.0225
    NV1D2708 0.0721
    NV1D2725 0.0144
    NV1D2739 0.0053
    NV1D2765 0.0097
    NV1D2748 0.0995
    NV1D2771 0.0103
    NV1D2770 0.0121
    NV1D2778 0.0644
    NV1D2782 0.0202
    NV1D2756 0.0466
    NV1D2759 0.0218
    NV1D2712 0.0558
    NV1D12  0.0127
    NV1D2673 0.0625
    NV1D2662 0.0433
    NV1D2669 0.2661
    NV1D2665 0.0389
    NV1D2731 0.2547
    NV1D2767 0.0238
    NV1D2730 0.2566
    NV1D2766 0.0198
    NV1D2667 0.0050
    NV1D2769 0.0142
    NV1D2719 0.0675
    NV1D2776 0.0633
    NV1D2663 0.0344
    NV1D2709 0.1841
    NV1D2720 0.0538
    NV1D12  0.0095
    NV1D2773 0.1921
    NV1D2810 0.0086
    NV1D2732 0.0262
    NV1D757  0.0026
    NV1D791  0.0206
    NV1D2310 0.0085
    NV1D2308 0.0179
    NV1D778  0.0094
    NV1D856  0.0247
    NV1D2309 0.0035
    NV1D846  0.0043
    NV1D2889 0.0107
    NV1D2887 0.0061
    NV1D2861 0.0469
    NV1D2729 0.1101
    NV1D2890 0.0088
    NV1D2899 0.0402
    NV1D2804 0.0044
    NV1D2734 0.0602
    NV1D2772 0.2050
    NV1D2775 0.2225
    NV1D2738 0.0512
    NV1D2740 0.0373
    NV1D2733 0.1913
    NV1D788  0.0000
    NV1D757  0.0021
    NV1D791  0.0007
    NV1D2310 0.0011
    NV1D2308 0.0014
    NV1D778  0.0019
    NV1D2294 0.0000
    NV1D856  0.0047
    NV1D2309 0.0023
    NV1D846  0.0020
    NV1D2896 0.0504
    NV1D2913 0.0203
    NV1D2910 0.0253
    NV1D2893 0.0569
    NV1D2909 0.0195
    NV1D2917 0.0339
    NV1D2914 0.0201
    NV1D2922 0.0554
    NV1D2902 0.0061
    NV1D2889 0.0022
    NV1D2887 0.0025
    NV1D2878 0.0272
    NV1D2877 0.0129
    NV1D2851 0.0029
    NV1D2850 0.0026
    NV1D2820 0.0020
    NV1D2819 0.0015
    NV1D2814 0.0163
    NV1D2918 0.0256
    NV1D2921 0.0533
    NV1D2905 0.0126
    NV1D2906 0.0189
    NV1D2881 0.0207
    NV1D2882 0.0223
    NV1D2869 0.0038
    NV1D2870 0.0187
    NV1D2867 0.0147
    NV1D2888 0.0045
    NV1D2816 0.0133
    NV1D2885 0.0025
    NV1D2974 0.0418
    NV1D2972 0.1089
    NV1D2971 0.0407
    NV1D2970 0.0557
    NV1D2969 0.0799
    • EXAMPLE 3 Characterization of Protoxin-II Variants
  • Select Protoxin-II variants were characterized in membrane depolarization and whole cell patch clamp assays to assess their potency and selectivity towards Nav1.7.
  • Veratridine-Induced Depolarization Inhibition Assay
  • The ability of the generated peptides to inhibit membrane depolarization induced by the Nav1.7 agonist veratridine (3-Veratroylveracevine; Biomol, Catalog#NA125) was measured with a veratridine-induced depolarization inhibition assay measuring decline in FRET (fluorescence resonance energy transfer) assay on a fluorescent resonance image plate reader (FLIPR® Tetra; Molecular Devices) using DISBAC2(3) (Invitrogen, K1018) as an electron acceptor and PTS18 (Trisodium 8-octadecyloxypyrene-1,3,6-trisulfonate) (Sigma) as a donor by exciting the donor at 390-420 nm and measuring FRET at 515-575 nm.
  • HEK293 cells stably expressing human Nav1.7 were cultured in DMEM/F-12 media (1:1), supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, 400 μg/mL geneticin and 100 μM NEAAs (all reagents from Invitrogen). 50 μL of harvested cells were plated at 25,000 cells/well into poly-lysine coated 384-well black clear bottom plates. The plates were incubated at room temperature (RT) for 15 min followed by an overnight incubation at 37° C. All incubations were done in the dark unless otherwise stated. The next day, the wells were washed 4 times with assay buffer (137 mM NaCl, 4 mM KCl, 2 mM MgCl2, 2 mM CaCl2, 5 mM Glucose, 10 mM HEPES, pH 7.4), and resuspended in 25 μL of assay buffer. 2× stock (6 μM) of the PTS18 dye was prepared by suspending the dye in 10% Pluronic F127 in DMSO at 1:1 (v/v ratio). 25 μL of the 2× PTS18 stock was added into the wells and the cells were stained for 30 min at RT, after which the dye was washed off with the assay buffer. Peptides were suspended at 3× their final concentration in the assay buffer containing 10 μM DISBAC2(3) and 400 μM VABSC-1 to suppress background fluorescence (Sigma, cat#201987). 25 μL/well of the suspended peptides were added into each well, and incubated for 60 minutes at RT. Depolarization was induced by 25 μM final concentration of veratridine (by adding 25 μL/well of 75 μM (3×) stock solution), and the reduction in the mean intensity of FRET dye fluorescence was measured 30-100 seconds after adding the agonist. A 1.3× dilution of each measured peptide occurred after adding veratridine by convention, the concentration at the beginning of the veratridine-induced depolarization inhibition assay is reported.
  • Concentration-response curves of synthetic Protoxin-II (Peptide International) were constructed in each experimental series and were used as controls. Fluorescence counts for each well were converted to % response by normalizing the signal to the difference between negative control (response to agonist veratridine alone) and positive control (response to veratridine in the presence of 10 μM tetracaine) values. For measurements, “spatial uniformity correction” (all fluorescence traces are normalized to the average initial starting intensity) and “subtract bias value” (subtract the initial starting intensity from each trace) were turned on in FLIPR® Tetra. Each data point represented the response in an individual well. All individual data points were used in a non-linear least-squares fitting procedure to find the best fit to a Hill function using Origin (Microcal). IC50 values were extracted from the resultant fitted curve. The mean responses of the positive (P) and negative (N) controls were used to calculate the % response in a well as follows: % response=100*(N−R)/(N−P).
  • Assay plates were accepted if the potency of control antagonists for that day were within ±0.5 log units of their historical mean.
  • QPatch Assay
  • HEK293 cells stably expressing human Nav1.5 (SEQ ID NO: 105), Nav1.7 (SEQ ID NO: 79) or Nav1.6 (SEQ ID NO: 407) were cultured in DMEM/F-12 media (1:1), supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, 400 μg/mL Geneticin and 100 μM NEAAs (all reagents from Invitrogen). Cells were maintained at 37° C. and in 5% CO2 and assayed upon reaching ˜50-90% confluency. CHO cells stably expressing human Nav1.6 in a tetracycline-inducible manner(SEQ ID NO: 407) were cultured in HAMs F12, supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, 10 μg/mL Blasticidin and 400 μg/mL Zeocin. Cells were maintained at 37° C. and in 5% CO2, and assayed upon reaching ˜50-90% confluency. Nav1.6 expression was induced with 1 μg/ml of tetracycline, 24-48 h prior to an experiment.
  • Before testing in QPatch HT (Sophion), cells were first dissociated using 0.05% trypsin (5 min at 37° C.), resuspended in CHO-S-SFM media (Life Technologies) and gently triturated to break up cell clumps. Cell density was adjusted to 1−2×106/mL with the same media and cells were the transferred to a cell “hotel” in QPatch HT and used in experiments for several hours. For giga-ohm seal formation and whole-cell patch clamp recording, the extracellular solution contained 137 mM NaCl, 5.4 mM KCl, 1 mM MgCl2, 2 mM CaCl2, 5 mM glucose, and 10 mM HEPES, pH=7.4 and osmolarity=315 mOsm. The intracellular solution contained 135 mM CsF, 10 mM CsCl, 5 mM EGTA, 5 mM NaCl and 10 mM HEPES, pH=7.3 and osmolarity=290 mOsm. The voltage protocol used in the assay was as follows. From a holding potential of −75 mV (Nav1.7), −60 mV (Nav1.6), or −105 mV (Nav1.5) cells were first hyperpolarized to −120 mV for 2 sec and then depolarized to 0 mV for 5 ms before returning to the holding potential. This protocol was repeated once every 60 sec during liquid applications (see below). Cells were otherwise held at the holding potential when the above voltage protocol was not executed. Upon establishment of the whole-cell recording configuration, a total of five applications of the extracellular solution (all containing 0.1% bovine serum albumin (BSA) with or without test compound, except for the last application, which contained 1 μM TTX or 10 mM lidocaine as a positive control) were made on to cells being recorded. The first liquid application contained only the control buffer (5 μL). The voltage protocol was executed 10 times (for a total duration of 10 min) five sec after the application. The next three liquid applications (5 μL each) contained a test compound (same compound at the same concentration for all three applications) or control buffer (for control cells only). Five seconds after each of these applications, the voltage protocol was again executed 10 times (also once per min). The last application contained positive (composed of three 10 μL sub-applications, each separated by 2 sec), five seconds after which the same voltage protocol was executed twice to obtain the baseline current. Currents were sampled at 25 kHz and filtered at 5 kHz with an 8-pole Bessel filter. The series resistance compensation level was set at 80%. For each cell, the peak current amplitude at 0 mV for each current trace in the first four liquid applications was first subtracted from that of the last trace in the presence of positive control and then normalized to that of the last trace in the first (control buffer) application as % inhibition. To control for current rundown, this (% inhibition) value for each cell in the presence of a test compound was further normalized to the average % inhibition value for control (typically 5-6) cells in the same experiment. The mean of the last two such values in the last compound application (i.e., the corrected % inhibition value for each concentration of a test compound) were taken as the % inhibition value for each cell at the particular compound concentration tested. The % inhibition values for all cells tested at each compound concentration were averaged and used in concentration response calculations. All experiments were performed at room temperature (˜22° C.). Data are expressed as mean±SE. Wild type Protoxin-II was included in each experiment as a positive control. Data were accepted only if the potency of Protoxin-II was within ±0.5 log units of its historical mean.
  • IC50 values for Nav1.7 for select Protoxin-II variants obtained using the veratridine-induced depolarization inhibition assay are shown in Table 6.
  • TABLE 6
    hNav1.7
    Veratridine-
    Protoxin-II Induced
    variant Depolarization
    Protoxin-II Peptide Inhibition
    Variant SEQ ID Assay
    Protein ID Peptide ID NO: IC50 (nM)
    NV1D12 5 NV1D12   2 4.1 ± 3.6
    NV1G1045 NV1D791  11 4.8 ± 0.4
    NV1D1332_1 NV1D1332 12 6.7 ± 0.5
    NV1D1336_1 NV1D1336 14 10.5 ± 1.2 
    NV1D1337_1 NV1D1337 15 10.3 ± 1.0 
    NV1G1049 NV1D2308 16 4.5 ± 0.4
    NV1G953  NV1D2670 17 22.2 ± 3.3 
    NV1G951  NV1D2674 18 4.0 ± 0.2
    NV1G963  NV1D2671 20 31.5 ± 6.4 
    NV1G949  NV1D2675 21 4.3 ± 0.3
    NV1G977  NV1D2665 22 4.9 ± 0.4
    NV1G957  NV1D2668 23 17.5 ± 2.6 
    NV1G965  NV1D2672 24 4.5 ± 0.3
    NV1G973  NV1D2662 25 4.0 ± 0.4
    NV1G975  NV1D2669 26 18.4 ± 5.7 
    NV1G971  NV1D2673 27 4.3 ± 0.5
    NV1G995  NV1D2663 28 4.2 ± 0.4
    NV1G961  NV1D2676 29 26.5 ± 2.9 
    NV1G911  NV1D2666 30 66.5 ± 36.7
    NV1G1133 NV1D2816 31  667 ± 93.6
    NV1G905  NV1D2735 32 60.0 ± 16.2
    NV1G979  NV1D2731 34 20.7 ± 7.2 
    NV1G1097 NV1D2810 35  339 ± 5750
    NV1G1099 NV1D2732 36  126 ± 26.9
    NV1G1011 NV1D2740 37 3.6 ± 9.9
    NV1G1105 NV1D2729 39 8.0 ± 0.9
    NV1G1013 NV1D2733 40 7.5 ± 2.9
    NV1G1095 NV1D2814 41  754 ± 51.3
    NV1G983  NV1D2730 43 25.5 ± 4.3 
    NV1G1003 NV1D2734 44 13.4 ± 0.8 
    NV1G1009 NV1D2738 45 2.6 ± 0.2
    NV1G1129 NV1D2867 49 >1000
    NV1G1121 NV1D2881 50  488 ± 72.2
    NV1G1123 NV1D2882 51  857 ± 65.7
    NV1G899  NV1D2774 52 50.5 ± 15.2
    NV1G1103 NV1D2861 54 >1000
    NV1G1127 NV1D2870 55  784 ± 84.8
    NV1G1007 NV1D2775 56 25.4 ± 2.0 
    NV1G1067 NV1D2893 57 75.5 ± 10.5
    NV1G1005 NV1D2772 59 15.6 ± 1.8 
    NV1G1061 NV1D2896 60 80.3 ± 7.1 
    NV1G1085 NV1D2877 61  441 ± 73.3
    NV1G1083 NV1D2878 62  680 ± 40.7
    NV1G1079 NV1D2889 64 12.1 ± 1.5 
    NV1G1001 NV1D2773 65 18.8 ± 1.5 
    NV1G1107 NV1D2890 66 25.8 ± 4.2 
    NV1G1109 NV1D2899 67 33.3 ± 6.7 
    NV1G1117 NV1D2905 68 713 ± 873
    NV1G1119 NV1D2906 69  940 ± 86.7
    NV1G1115 NV1D2921 70  586 ± 71.7
    NV1G1075 NV1D2922 71  204 ± 45.7
    NV1G1069 NV1D2909 72 97.1 ± 10.1
    NV1G1065 NV1D2910 73  441 ± 41.7
    NV1G1063 NV1D2913 74 79.7 ± 9.3 
    NV1G1073 NV1D2914 75  135 ± 7.8 
  • hNav1.7
    Veratndine-
    Protoxin-II Induced
    variant Depolarization
    Protoxin-II Peptide Inhibition
    Variant SEQ ID Assay
    Protein ID Peptide ID NO: IC50 (nM)
    NV1G1071 NV1D2917 76 197 ± 48.3
    NV1G1113 NV1D2918 77 983 ± 98.7
    NV1G1153 NV1D3034 78 10.3 ± 2.1  
  • Select Protoxin-II variants were tested for selectivity against human Nav1.5 using QPatch. IC50 values for both Nav1.7 and Nav1.5 for select peptides obtained using QPatch are shown in Table 7.
  • TABLE 7
    Protoxin-
    II variant
    Protoxin-II Peptide hNavl .7 hNavl .5
    Variant SEQ ID QPatch
    Protein ID Peptide ID NO: IC50 (nM) IC50 (nM)
    NV1D12_5 NV1D12    2 2.2 ± 1.3 >1000
    NV1G899  NV1D2774 52 18.7 ± 13.6 >3000
    NV1G1007 NV1D2775 56 4.0 ± 8.9 >3000
    NV1G1005 NV1D2772 59 6.2 ± 3.2 >3000
    NV1G1001 NV1D2773 65 4.3 ± 3.3 >3000
    NV1G1153 NV1D3034 78 4.3 ± 4.3 >1000
    • EXAMPLE 4 Generation and Characterization of Combinatorial Protoxin-II Variants
  • Combinatorial libraries were designed to test for additive effects of select single position hits in an attempt to generate Nav1.7 antagonists with further improved potency and selectivity profile compared to the native peptide using several approaches.
  • A limited amino acid scan was conducted at all non-cysteine Protoxin-II positions using A, D, Q, R, K and S for diversification. In these experiments, Protoxin-II was expressed and tested as monovalent Fc fusion protein as described in Example 1. From this scan, substitutions Y1Q, W7Q, S11A, were identified that improved potency and/or selectivity of the resulting variants.
  • A full amino acid scan (excluding Cys and Trp) at positions M6 and M19 was also conducted. M19F substitution was identified from this scan that improved potency and/or selectivity of the resulting variants.
  • Protoxin-II/Huwentoxin-IV single position chimeras were designed bidirectionally. The purpose of this library was to obtain Protoxin-II variants that retained potency and selectivity profile of the wild type Protoxin-II and would achieve beneficial refolding properties associated with Huwentoxin-IV. Substitutions R22T and E12N were identified from this scan.
  • Peptide NV1G1153 was further engineered by diversifying position Y1 by a limited amino acid scan using R, K, T, A, D, E, Q and S, and by charge cluster engineering, where all sets of charged residues in the three-dimensional structure of the peptide (D10/E12, K4/E17, D10/E12/R13) were mutated.
  • N- and C-terminal extensions were introduced to select peptides, including NV1G1153 with the purpose of improving peptide distribution to the site of action and of improving half-life of the peptides without significantly increasing the molecular weight of the resulting peptide. The N- and C-terminal extensions that were used are shown in Table 8 and 9, respectively, and are described in Oi et. al., Neuroscience Letters 434, 266-272, 2008; Whitney et. al., Nature Biotechnology 2011 29:4, 352-356; Sockolosky et. al., (2012) 109:40, 16095-16100. Cell penetrating peptides HIV Tat and polyarginine were also used. Various linkers were used to couple the Protoxin-II variant to the N- and/or C-terminal extensions. The linkers used are shown in Table 10.
  • Protoxin-II variants from each campaign were tested for their potency and selectivity for Nav1.7 using methods described in Example 3. The amino acid sequences of the variants that inhibited Nav1.7 with an IC50 value of 200 nM or less are shown in Table 3. Table 11 shows the amino acid substitutions in select variant when compared to the wild type Protoxin-II, and the IC50 values for Nav1.7 inhibition in the veratridine-induced depolarization inhibition assay.
  • TABLE 8
    N-terminal extension
    Amino acid sequence SEQ ID NO:
    GPAAAAA 372
    GPAPAPA 373
    GGGGG 374
    GPCCNCSSKWCRDHSRCC 375
    GPSPGARAF 376
    GPDGPWRKM 377
    GPFGQKASS 378
    GPCRTIGPSVC 379
    GPSHSNTQTLAKAPEHTG 380
    GPQRFVTGHFGGLYPANG 381
    GPGWCGDPGATCGKLRLYCGSGFCDSYTKTCKDKSSA 382
    APAPAPAPAP 383
    GPYGRKKRRQRRR 384
    GPRRRRRRRRRRR 385
  • TABLE 9
    C-terminal extensions
    SEQ ID
    Amino acid sequence NO:
    CRTIGPSVC 386
    YGRKKRRQRRR 387
    GGGGG 374
    DGPWRKM 388
    CCNCSSKWCRDHSRCC 389
    RRRRRRRRRRR 390
    SHSNTQTLAKAPEHTG 391
    APAPA 392
    AAAAA 393
    FGQKASS 394
    QRFVTGHFGGLYPANG 395
    SPGARAF 396
    GPGWCGDPGATCGKLRLYCCSGFCDAYTKTCKDKSSA 397
  • TABLE 10
    Linkers
    Amino acid sequence SEQ ID NO:
    GSAPAPAPAPAPGS 398
    GSAPAPAPAPAPAPAPAPAPAPGS 399
    GGGGSAPAPAPAPAPAPAPAPAPAPAPAPAPA 400
    PAPGGGGS
    APAPA 392
    GSGGGGSAPAPAPAPAPAPAPAPAPAPGGGGS 401
    GS
    APAPAPAPAP 383
    APAPAPAPAPAPAPAPAPAP 402
  • TABLE 11
    Protoxin-II
    variant Protein Nav1.7
    Protein peptide SEQ ID IC50
    name name NO: Substitutions (nM) SE
    NV1G1728 NV1D3541 281 Y1A, W7Q, S11R, E12N, 9.4 1.2
    M19F, R22T, K26R
    NV1G1870 NV1D3583 321 Y1A, W7Q, S11A, E12R, M19F, 13.1 1.57
    V20S
    NV1G1752 NV1D3532 272 Y1A, W7Q, S11A, E12K, M19F, 17.3 2
    R22T, K26R
    NV1G1749 NV1D3587 326 Y1A, W7Q, S11A, E12N, 18.3 2.6
    M19F, V20S
    NV1G1725 NV1D3572 310 Y1A, W7Q, S11A, E12R, M19F, 19.8 2.2
    R22T
    NV1G1745 NV1D3537 277 Y1A, W7Q, S11A, E12K, M19F, 21.4 4.1
    V20S, R22T, K26R
    NV1G1720 NV1D3565 304 Y1A, W7Q, S11A, E12R, M19F, 23 2.8
    V20S, R22T
    NV1G1761 NV1D3550 290 Y1A, W7Q, S11R, M19F, R22T, 25.8 2.7
    K26R
    NV1G1746 NV1D3576 314 Y1A, W7Q, S11A, E12N, M19F, 26.7 5.2
    R22T
    NV1G979 NV1D2731 34 Y1A, W7Q, S11A 20.7 7.2
    NV1G953 NV1D2670 17 Y1A, W7Q 22.2 3.3
    NV1G1519 NV1D3006 133 Y1Q, W7Q, S11A, E12R, 4.03 1.05
    M19F
    NV1G1007- NV1D2775- 111 Y1Q, W7Q, S11A, M19F 5.06 0.473
    NH2 NH2
    NV1G1517 NV1D3004 131 Y1Q, W7Q, S11R, M19F 6.23 1.56
    (-GP) N-Ac- (-GP) N-Ac- 114 Y1Q, W7Q, S11A, M19F, V20S, 6.43 1.06
    NV1G1137- NV1D2974- R22T
    NH2 NH2
    NV1G1776 NV1D3339 172 Y1Q, Q3R, W7Q, S11R, M19F, 6.57 0.675
    R22T, K26R
    NV1G1153- NV1D3034- 119 Y1Q, W7Q, S11R, M19F, R22T, 7.1 0.9
    NH-methyl NH-methyl K26R
    (-GP) N-Ac- (-GP) N-Ac- 121 Y1Q, W7Q, S11R, M19F, R22T, 7.63 1.04
    NV1G1153- NV1D3034- K26R
    NH2 NH2
    NV1G1523 NV1D3012 135 Y1Q, W7Q, S11R, E12N, M19F 7.74 0.904
    NV1G1515 NV1D3005 132 Y1Q, W7Q, S11A, E12N, M19F 7.83 1.38
    NV1G1187 NV1D3015 138 Y1Q, W7Q, S11R, M19F, K26R 8.86 2.28
    NV1G1521 NV1D3018 141 Y1Q, W7Q, S11A, E12N, M19F, 9.79 2.91
    K26R
    NV1G1267 NV1D3044 150 Y1Q, W7Q, S11R, E12N, M19F, 9.8 0.849
    R22T, K26R
    NV1G1153 NV1D3034 78 Y1Q, W7Q, S11R, M19F, R22T, 10.3 2.14
    K26R
    NV1G1836 NV1D3359 190 Y1Q, W7Q, T8S, S11R, M19F, 10.5 0.739
    R22T, K26R
    NV1G1593 NV1D3050 153 Y1Q, W7Q, S11R, E12K, M19F 10.8 1.3
    NV1G1215 NV1D3048 152 Y1Q, W7Q, S11A, E12K, M19F 11.1 1.05
    NV1G1868 NV1D3353 185 Y1Q, W7Q, T8R, S11R, M19F, 11.2 1.25
    R22T, K26R
    NV1G1525 NV1D3013 136 Y1Q, W7Q, S11R, E12R, M19F 11.3 1.83
    NV1G1775 NV1D3340 173 Y1Q, Q3K, W7Q, S11R, M19F, 11.5 0.798
    R22T, K26R
    NV1G1833 NV1D3381 210 Y1Q, W7Q, S11RK14Q, M19F, 12.2 1.56
    R22T, K26R
    NV1G1153- NV1D3034- 117 Y1Q, W7Q, S11R, M19F, R22T, 12.2 1
    NH2 NH2 K26R
    NV1G1777 NV1D3342 175 Y1Q, Q3A, W7Q, S11R, M19F, 12.8 2.67
    R22T, K26R
    NV1G1259 NV1D3058 158 Y1Q, W7Q, S11A, E12K, M19F, 12.9 1.29
    R22T, K26R
    NV1G1511 NV1D3032 146 Y1Q, W7Q, S11R, E12N, M19F, 13 203
    K26R
    NV1G1527 NV1D3031 145 Y1Q, W7Q, S11R, E12R, M19F, 13 1.36
    R22T
    NV1G1265 NV1D3062 159 Y1Q, W7Q, S11R, E12K, M19F, 13.2 1.43
    R22T, K26R
    NV1G1781 NV1D3388 217 Y1Q, W7Q, S11RE17Q, M19F, 13.5 1.14
    R22T, K26R
    NV1G1824 NV1D3354 186 Y1Q, W7Q, T8K, S11R, M19F, 13.9 1.12
    R22T, K26R
    NV1G1772 NV1D3352 184 Y1Q, K4S, W7Q, S11R, M19F, 14.2 2.01
    R22T, K26R
    NV1G1509 NV1D3033 147 Y1Q, W7Q, S11R, E12R, M19F, 14.5 2.18
    K26R
    NV1G1779 NV1D3351 183 Y1Q, K4Q, W7Q, S11R, M19F, 15.3 2.39
    R22T, K26R
    NV1G1687 NV1D3526 266 Y1Q, W7Q, S11R, M19F, R22T, 15.4
    K26R
    NV1G1269 NV1D3045 151 Y1Q, W7Q, S11R, E12R, M19F, 15.6 1.39
    R22T, K26R
    NV1G1623 NV1D3056 156 Y1Q, W7Q, S11R, E12K, M19F, 16.2 2.99
    R22T
    NV1G1859 NV1D3376 205 Y1Q, W7Q, S11R, K14R, M19F, 16.3 2.53
    R22T, K26R
    NV1G1153- NV1D3034- 118 Y1Q, W7Q, S11R, M19F, R22T, 16.6 1.4
    NH-butyl NH-butyl K26R
    NV1G1211 NV1D3036 149 Y1Q, W7Q, S11A, E12R, M19F, 17.2 1.55
    R22T, K26R
    NV1G1885 NV1D3254 165 Y1Q, W7Q, S11A, M19F 17.5 2.45
    NV1G1730 NV1D3542 282 Y1Q, W7Q, S11R, E12N, M19F, 17.7 2.5
    V20S, R22T, K26R
    NV1G1263 NV1D3051 154 Y1Q, W7Q, S11A, E12K, M19F, 17.9 1.78
    R22T
    NV1G1818 NV1D3368 122 Y1Q, W7Q, S11R, E12T, 17.9 1.89
    M19F, R22T, K26R
    NV1G1153 NV1D3034 116 Y1Q, W7Q, S11R, M19F, R22T, 18 2.5
    (synthetic) K26R
    NV1G1823 NV1D3367 197 Y1Q, W7Q, S11R, E12Q, M19F, 18.6 2.17
    R22T, K26R
    NV1G1820 NV1D3362 193 Y1Q, W7Q, D10T, S11R, M19F, 20.1 2.32
    R22T, K26R
    NV1G1811 NV1D3369 199 Y1Q, W7Q, S11R, R13K, M19F, 20.4 2.44
    R22T, K26R
    NV1G1810 NV1D3358 189 Y1Q, W7Q, T8Q, S11R, M19F, 20.5 2.11
    R22T, K26R
    NV1G1818- NV1D3368- 123 Y1Q, W7Q, S11R, E12T, M19F, 20.5 2.8
    NH2 NH2 R22T, K26R
    NV1G1137 NV1D2974 129 Y1Q, W7Q, S11A, M19F, V20S, 21.6 1.34
    (synthetic) R22T
    NV1G1221 NV1D3017 140 Y1Q, W7Q, S11A, E12R, M19F, 21.9 2.48
    R22T
    NV1G1722 NV1D3533 273 Y1Q, W7Q, S11A, E12K, M19F, 22.4 3.5
    V20S, R22T, K26R
    NV1G1767 NV1D3345 177 Y1Q, Q3S, W7Q, S11R, M19F, 22.4 2.52
    R22T, K26R
    NV1G1769 NV1D3346 178 Y1Q, K4R, W7Q, S11R, M19F, 23.2 3.39
    R22T, K26R
    NV1G1780 NV1D3387 216 Y1Q, W7Q, S11R, E17D, M19F, 23.7 2.85
    R22T, K26R
    NV1G1886 NV1D3249 162 Y1Q, W7Q, S11A, M19F 24.1 11.5
    NV1G1812 NV1D3382 211 Y1Q, W7Q, S11R, K14S, M19F, 24.3 2.14
    R22T, K26R
    NV1G1857 NV1D3366 196 Y1Q, W7Q, D10S, S11R, M19F, 24.6 3.8
    R22T, K26R
    NV1G1821 NV1D3378 207 Y1Q, W7Q, S11R, K14A, M19F, 24.8 2.66
    R22T, K26R
    NV1G1993 NV1D3792 335 Y1Q, W7Q, S11R, M19F, R22T, 25.3 2.8
    K26R
    NV1G1007 NV1D2775 56 Y1Q, W7Q, S11A, M19F 25.4 2
    NV1G1787 NV1D3396 224 Y1Q, W7Q, S11R, G18Q, M19F, 26.4 3.17
    R22T, K26R
    NV1G1257 NV1D3016 139 Y1Q, W7Q, S11A, E12N, M19F, 26.6 3.1
    R22T
    NV1G1153 NV1D3034 116 Y1Q, W7Q, S11R, M19F, R22T, 27.3 2.02
    (synthetic) K26R
    NV1G1803 NV1D3403 230 Y1Q, W7Q, S11R, M19F, R22T, 28.3 1.97
    K26R, K27A
    (-GP) N-Ac- N-Ac- 115 Y1Q, W7Q, S11A, M19F, V20S, 28.6 2.23
    NV1G1137 NV1D2974 R22T
    NV1G1531 NV1D3019 142 Y1Q, W7Q, S11A, E12R, M19F, 28.7 4.78
    K26R
    NV1G1513 NV1D3007 134 Y1Q, W7Q, S11A, M19F, K26R 29.6 9.17
    NV1G1991 NV1D3789 333 Y1Q, W7Q, S11R, M19F, R22T, 29.9 5.19
    K26R
    NV1G1013 NV1D2733 40 Y1R, W7Q, M19F 7.54 2.9
    NV1G1740 NV1D3580 318 Y1R, W7Q, S11A, E12R, M19F, 8.4 1.5
    V20S
    NV1G1757 NV1D3538 278 Y1R, W7Q, S11R, E12N, M19F, 11.6 1.4
    R22T, K26R
    NV1G1741 NV1D3569 307 Y1R, W7Q, S11A, E12R, M19F, 11.9 0.8
    R22T
    NV1G1715 NV1D3584 322 Y1R, W7Q, S11A, E12N, M19F, 13.9 1.4
    V20S
    NV1G1754 NV1D3529 269 Y1R, W7Q, S11A, E12K, M19F, 14.6 1.7
    R22T, K26R
    NV1G1005 NV1D2772 59 Y1R, W7Q, S11A, M19F 15.6 1.8
    NV1G1733 NV1D3577 315 Y1R, W7Q, S11A, M19F, V20S 18.8 2.2
    NV1G1744 NV1D3534 274 Y1R, W7Q, S11A, E12K, M19F, 20.6 2.2
    V20S, R22T, K26R
    NV1G1724 NV1D3562 301 Y1R, W7Q, S11A, E12R, M19F, 23.6 2.7
    V20S, R22T
    NV1G1735 NV1D3566 305 Y1R, W7Q, S11A, M19F, R22T 23.7 2.5
    NV1G1760 NV1D3543 283 Y1R, W7Q, S11E, E12N, M19F, 23.8 1.9
    V20S, R22T, K26R
    NV1G1759 NV1D3547 287 Y1R, W7Q, S11R, M19F, R22T, 26.5 2.1
    K26R
    NV1G1751 NV1D3558 297 Y1R, W7Q, S11A, E12N, M19F, 26.7 3.4
    V20S, R22T
    NV1G1726 NV1D3551 291 Y1R, W7Q, S11R, M19F, V20S, 29.3 3.8
    R22T, K26R
    NV1G1105 NV1D2729 39 Y1R, W7Q, S11A 8 8.85E−01
    NV1G957 NV1D2668 23 Y1R, W7Q 17.5 2.6
    (-GP) (-GP) 109 Y1S, W7Q, S11A, M19F 9.47 1.28
    NV1G1001 NV1D2773
    (-GP) -GP) 110 Y1S, W7Q, S11A, M19F 11.5 0.61
    NV1G1001- NV1D2773-
    NH-methyl NH-methyl
    NV1G1003 NV1D2734 44 Y1S, W7Q, M19F 13.4 0.8
    NV1G1864 NV1D3581 319 Y1S, W7Q, S11A, E12R, M19F, 14.6 1.7
    V20S
    NV1G1748 NV1D3530 270 Y1S, W7Q, S11A, E12K, M19F, 15.6 2.2
    R22T, K26R
    NV1G1758 NV1D3548 288 Y1S, W7Q, S11R, M19F, R22T, 17.6 1.9
    K26R
    NV1G1727 NV1D3544 284 Y1S, W7Q, S11R, E12N, M19F, 17.8 2.2
    V20S, R22T, K26R
    NV1G1719 NV1D3570 308 Y1S, W7Q, S11A, E12R, M19F, 18.1 1.5
    R22T
    NV1G1742 NV1D3535 275 Y1S, W7Q, S11A, E12K, M19F, 18.7 2.8
    V20S, R22T, K26R
    NV1G1001 NV1D2773 65 Y1S, W7Q, S11A, M19F 18.8 1.5
    NV1G1753 NV1D3585 323 Y1S, W7Q, S11A, E12N, M19F, 19.4 2.1
    V20S
    NV1G1762 NV1D3539 279 Y1S, W7Q, S11R, E12N, M19F, 19.4 1.8
    R22T, K26R
    NV1G1755 NV1D3574 312 Y1S, W7Q, S11A, E12N, M19F 22.3 2.7
    R22T
    NV1G1717 NV1D3563 302 Y1S, W7Q, S11A, E12R, M19F, 22.4 2.4
    V20S, R22T
    NV1G1866 NV1D3559 298 Y1S, W7Q, S11A, E12N, M19F, 26.5 5.02
    V20S, R22T
    NV1G1721 NV1D3552 292 Y1S, W7Q, S11R, M19F, V20S, 28.1 3.7
    R22T, K26R
    NV1G975 NV1D2669 26 Y1S, W7Q 18.4 5.7
    NV1G983 NV1D2730 43 Y1S, W7Q, S11A 25.5 4.3
    NV1G1750- NV1D3586- 325 W7Q, S11A, E12N, M19F, V20S 4.23 0.33
    NH2 NH2
    NV1G1747 NV1D3531 271 W7Q, S11A, E12K, M19F, R22T, 13 2.1
    K26R
    NV1G1763 NV1D3S40 280 W7Q, S11R, E12N, M19F, R22T, 16 1.5
    K26R
    NV1G1739 NV1D3582 320 W7Q, S11A, E12R, M19F, V20S 17.8 2.2
    NV1G1750 NV1D3586 324 W7Q, S11A, E12N, M19F, 20.5 2.2
    V20S
    NV1G1718 NV1D3571 309 W7Q, S11A, E12R, M19F, R22T 21 2.3
    NV1G1865 NV1D3560 299 W7Q, S11A, E12N, M19F, V20S, 27.2 3.42
    R22T
    NV1G1766 NV1D3549 289 W7Q, S11R, M19F, R22T, K26R 27.5 3.2
    NV1G961 NV1D2676 29 W7Q, S11A 26.5 2.9
    NV1G951 NV1D2674 18 Y1A, S11A 4.03 0.2
    NV1G1011 NV1D2740 37 Y1Q, S11A, M19F 3.62 9.9
    NV1G977 NV1D2665 32 Y1Q, M19F 4.9 0.4
    NV1G949 NV1D2675 21 Y1Q, S11A 4.33 0.3
    NV1G973 NV1D2662 25 Y1R, M19F 4.03 0.4
    NV1G965 NV1D2672 24 Y1R, S11A 4.5 0.3
    NV1G1009 NV1D2738 45 Y1S, S11A, M19F 2.57 0.2
    NV1G995 NV1D2663 28 Y1S, M19F 4.19 0.4
    NV1G1107- NV1D2890- 112 Y1S, M6F, S11A, M19L 9.12 1.17
    NH2 NH2
    NV1G971 NV1D2673 27 Y1S, S11A 4.31 0.5
    NV1G1782 NV1D3383 212 Y1Q, W7Q, S11R, E17R, M19F 30.3 4.06
    R22T, K26R,
    NV1G1990 NV1D3788 332 Y1Q, W7Q, S11R, M19F, R22T, 30.3 4.78
    K26R,
    (-GP) N-Ac- (-GP) N-Ac- 120 Y1Q, W7Q, S11R, M19F, R22T, 30.4 2.96
    NV1G1153- NV1D3034 K26R
    NV1G1786 NV1D3389 218 Y1Q, W7Q, S11R, E17S, M19F, 30.8 4.48
    R22T, K26R,
    NV1G1147 NV1D2969 124 Y1S, W7Q, S11A, M19F, 31 6.15
    V20S
    NV1G1764 NV1D3554 294 Y1A, W7Q, S11R, M19F, V20S, 31.4 3.3
    R22T, K26R
    NV1G963 NV1D2671 20 Y1Q, W7Q 31.5 6.4
    NV1G1835 NV1D3379 208 Y1Q, K4D, W7Q, S11R, M19F, 31.6 2.88
    R22T, K26R
    NV1G1231 NV1D3035 148 Y1Q, W7Q, S11A, E12N, M19F, 32 4.9
    R22T, K26R
    NV1G1743 NV1D3564 303 W7Q, S11A, E12R, M19F, V20S, 32.3 3.1
    R22T
    NV1G1960 NV1D3803 345 Y1Q, W7Q, S11R, M19F, R22T, 32.3 5.33
    K26R
    NV1G1924 NV1D3470 250 Y1Q, W7Q, S11R, M191, R22T, 32.5 403
    K26R
    NV1G1756 NV1D3575 313 W7Q, S11A, E12N, M19F, R22T 33.2 3.9
    NV1G1109 NV1D2899 67 Y1S, W7Q, S11A, M19L 33.3 6.7
    NV1G1818 NV1D3368 122 Y1Q, W7Q, S11R, E12T, M19F, 33.5 10.7
    R22T, K26R
    NV1G1784 NV1D3386 215 Y1Q, W7Q, S11R, E17A, M19F, 33.6 4.71
    R22T, K26R
    NV1G1141 NV1D2972 127 Y1Q, W7Q, S11A, M19F, V20S 34.1 6.2
    NV1G1774 NV1D3347 179 Y1Q, K4T, W7Q, S11R, M19F, 34.2 5.99
    R22T, K26R
    NV1G1881 NV1D3257 167 Y1Q, W7Q, S11A, M19F 34.2 2.81
    NV1G1915 NV1D3467 249 Y1Q, W7Q, S11R, E17G, M19F, 34.5 4
    R22T, K26R
    NV1G1984 NV1D3806 348 Y1Q, W7Q, S11R, M19F, R22T, 35.1 4.56
    K26R
    NV1G1716 NV1D3561 300 Y1A, W7Q, S11A, E12N, M19F, 35.6 5
    V20S, R22T,
    NV1G1255 NV1D3014 137 Y1Q, W7Q, S11R, M19F, R22T 36.1 5.37
    NV1G1959 NV1D3818 357 Y1Q, W7Q, S11R, M19F, R22T, 36.3 204
    K26R
    NV1G1825 NV1D3377 206 Y1Q, W7Q, S11R, K14T, M19F, 36.4 4.83
    R22T, K26R
    NV1G1723 NV1D3536 276 W7Q, S11A, E12K, M19F, V20S, 37 5.4
    R22T, K26R
    NV1G1732 NV1D3555 295 Y1R, W7Q, S11A, M19F, V20S, 37.4 4.3
    R22T,
    NV1G1983 NV1D3809 350 Y1Q, W7Q, S11R, M19F, R22T, 38.9 4.81
    K26R
    NV1G1982 NV1D3805 347 Y1Q, W7Q, S11R, M19F, R22T, 41.2 5.44
    K26R
    NV1G1785 NV1D3385 214 Y1Q, W7Q, S11R, E17T, M19F, 41.5 6.5
    R22T, K26R
    NV1G1583 NV1D3030 144 Y1Q, W7Q, S11R, E12N, M19F, 41.9 5.15
    R22T
    NV1G1729 NV1D3545 285 W7Q, S11R, E12N, M19F, V20S, 42.8 4.6
    R22T, K26R
    NV1G1007 NV1D2775 56 Y1Q, W7Q, S11A, M19F 42.9 6.7
    NV1G1734 NV1D3S68 306 Q1A, W7Q, S11A, M19F, R22T 44 8.3
    NV1G1683 NV1D3523 263 Y1Q, W7Q, S11R, M19F, R22T, 44.7
    K26R
    NV1G1834 NV1D3360 191 Y1Q, W7Q, D10R, S11R, M19F, 45.2 3.79
    R22T, K26R
    NV1G1795 NV1D3401 229 Y1Q, W7Q, S11R, M19F, R22T, 45.5 6.58
    K26R, K27R
    NV1G1689 NV1D3514 255 Y1Q, W7Q, S11R, M19F, R22T, 46.4
    K26R
    NV1G2043 NV1D3835 370 Y1Q, W7Q, S11R, M19P, R22T, 46.4 4.09
    K26R
    NV1G1783 NV1D3384 213 Y1Q, W7Q, S11R, E17K, M19F, 46.8 7.39
    R22T, K26R
    NV1G1239 NV1D3020 143 Y1Q, W7Q, S11A, M19F, R22T, 47.2 7.84
    K26R
    NV1G1788 NV1D3399 227 Y1Q, W7Q, S11R, M19F, V20S, 47.3 6.36
    R22T, K26R
    NV1G899 NV1D2774 52 Y1A, W7Q, S11A, M19F 50.5 15.2
    NV1G2057 NV1D3799 341 Y1Q, W7Q, S11R, M19F, R22T, 50.6 6.33
    K26R
    NV1G1738 NV1D3578 316 W7Q, S11A, M19F, V20S, 50.7 5.7
    NV1G1713 NV1D3525 265 Y1Q, W7Q, S11R, M19F, R22T, 52.3
    K26R
    NV1G1765 NV1D3553 293 W7Q, S11R, M19F, V20S, R22T, 52.4 10
    K26R
    NV1G1916 NV1D3465 247 Y1Q, W5F, W7Q, S11R, M19F, 52.8 10.3
    R22T, K26R
    NV1G1977 NV1D3804 346 Y1Q, W7Q, S11R, M19F, R22T, 53.6 6.27
    K26R
    NV1G1879 NV1D3259 168 Y1Q, W7Q, S11A, M19F 54.9 7.62
    NV1G1884 NV1D3256 166 Y1Q, W7Q, S11A, M19F 55.7 10.5
    NV1G1986 NV1D3819 358 Y1Q, W7Q, S11R, M19F, R22T, 56 6.57
    K26R
    NV1G1633 NV1D3251 163 Y1Q, W7Q, S11A, M19F 56.1 13.9
    NV1G1880 NV1D3261 170 Y1Q, W7Q, S11A, M19F 57 6.25
    NV1G1985 NV1D3808 349 Y1Q, W7Q, S11R, M19F, R22T, 57 6.74
    K26R
    NV1G1849 NV1D3400 228 Y1Q, W7Q, S11R, M19F, V20Q, 57.3 9.52
    R22T, K26R
    NV1G1883 NV1D3260 169 Y1Q, W7Q, S11A, M19F 57.6 6.91
    NV1G1145 NV1D2970 125 Y1S, W7Q, S11A, M19P, R22T 58 18.8
    NV1G1697 NV1D3517 258 Y1Q, W7Q, S11R, M19F, R22T, 58.5
    K26R
    NV1G1737 NV1D3579 317 Y1A, W7Q, S11A, M19F, V20S 59.9 9.6
    NV1G1978 NV1D3833 368 Y1Q, W7Q, S11R, M1912, R22T, 60.3 9.57
    K26R
    NV1G1954 NV1D3800 342 Y1Q, W7Q, S11R, M19F, R22T, 60.9 6.43
    K26R
    NV1G1989 NV1D3791 334 Y1Q, W7Q, S11R, M19F, R22T, 61.8 8.66
    K26R
    NV1G1815 NV1D3380 209 Y1Q, K4E, W7Q, S11R, M19F, 64 10.5
    R22T, K26R
    NV1G1967 NV1D3793 336 Y1Q, W7Q, S11R, M19F, R22T, 64.6 8.19
    K26R
    NV1G1869 NV1D3573 311 Y1R, W7Q, S11A, E12N, M19F, 64.7 50.7
    R22T
    NV1G1872 NV1D3777 330 Y1Q, W7Q, S11R, M19F, R22T, 64.9 15.3
    K26R
    NV1G1979 NV1D3834 369 Y1Q, W7Q, S11R, M19F, R22T, 65.5 7.59
    K26R
    NV1G1827 NV1D3365 195 Y1Q, W7Q, D10Q, S11R, M19F, 66.1 10.1
    R22T, K26R
    NV1G1768 NV1D3341 174 Y1Q, Q3T, W7Q, S11R, M19F, 66.2 9.32
    R22T, K26R
    NV1G911 NV1D2666 30 W7Q, M19F 66.5 36.7
    NV1G1856 NV1D3397 225 Y1Q, W7Q, S11R, G18S, M19F, 66.7 7.31
    R22T, K26R
    NV1G1973 NV1D3810 351 Y1Q, W7Q, S11R, M19F, R22T, 66.9 7.04
    K26R
    NV1G1855 NV1D3398 226 Y1Q, W7Q, S11R, M19F, V20S, 67.3 11
    R22T, K26R
    NV1G1961 NV1D3802 344 Y1Q, W7Q, S11R, M19F, R22T, 68 8.23
    K26R
    NV1G1846 NV1D3431 244 Y1Q, K4E, W7Q, S11R, E17K, 68.6 13.9
    M19F, R22T, K26R
    NV1G1771 NV1D3348 180 Y1Q, K4A, W7Q, S11R, M19F, 70.6 15.9
    R22T, K26R
    NV1G1691 NV1D3520 261 Y1Q, W7Q, S11R, M19F, R22T, 71.4
    K26R
    NV1G1681 NV1D3511 252 Y1Q, W7Q, S11R, M19F, R22T, 71.5
    K26R
    NV1G1968 NV1D3822 359 Y1Q, W7Q, S11R, M19E, R22T, 74.2 11.1
    K26R
    NV1G1813 NV1D3424 238 Y1Q, W7Q, D10K, S11R, E12K, 75.2 12.2
    M19F, R22T, K26R
    NV1G1067 NV1D2893 57 Y1Q, W7Q, S11A, M19L 75.5 10.5
    NV1G1867 NV1D3546 286 Y1A, W7Q, S11R, E12N, M19F, 76 17.6
    V20S, R22T, K26R
    NV1G1143 NV1D2971 126 Y1S, W7Q, S11A, M19F, V20S, 77.5 22.1
    R22T
    NV1G1806 NV1D3409 232 Y1Q, W7Q, S11R, M19F, R22T, 79.1 11.3
    K26R, K28T
    NV1G1061 NV1D2896 60 Y1R, W7Q, S11A, M19L 80.3 7.13
    NV1G1793 NV1D3419 236 Y1Q, W7Q, S11R, M19F, R22T, 80.9 11.9
    K26R, W30D
    NV1G1613 NV1D3057 157 Y1Q, W7Q, S11R, E12K, W19F, 83.4 16.6
    K26R
    NV1G1585 NV1D3052 155 Y1Q, W7Q, S11A, 84.8 28.8
    E12K, M19F, K26R
    NV1G1707 NV1D3524 264 Y1Q, W7Q, S11R, M19F, R22T, 84.9
    K26R
    NV1G1773 NV1D3350 182 Y1Q, K4E, W7Q, S11R, M19F, 85.6 14.4
    R22T, K26R
    NV1G1949 NV1D3828 364 Y1Q, W7Q, S11R, M19F, R22T, 87.5 11
    K26R
    NV1G1976 NV1D3811 352 Y1Q, W7Q, S11R, M19F, R22T, 87.7 15.7
    K26R
    NV1G1956 NV1D3801 343 Y1Q, W7Q, S11R, M19F, R22T, 88.1 11.4
    K26R
    NV1G1975 NV1D3832 367 Y1Q, W7Q, S11R, M19F, R22T, 88.4 123
    K26R
    NV1G1839 NV1D3774 328 Y1Q, W7Q, S11R, M19F, R22T, 88.6 19.6
    K26R
    NV1G1971 NV1D3830 366 Y1Q, W7Q, S11R, M19F, R22T, 88.6 9.88
    K26R
    NV1G1882 NV1D3262 171 Y1Q, W7Q, S11A, M19F 89.2 8.32
    NV1G1950 NV1D3797 339 Y1Q, W7Q, S11R, M19F, R22T, 91.1 13.5
    K26R
    NV1G1828 NV1D3363 194 Y1Q, W7Q, D10A, S11R, M19F, 93.1 15.3
    R22T, K26R
    NV1G1139 NV1D2973 128 Y1Q, W7Q, S11A, M19F, R22T 93.9 19.5
    NV1G1842 NV1D3430 243 Y1Q, K4D, W7Q, S11R, E17K, 93.9 14.1
    M19F, R22T, K26R
    NV1G11948 NV1D3798 340 Y1Q, W7Q, S11R, M19F, R22T, 94.5 17.8
    K26R
    NV1G1807 NV1D3408 231 Y1Q, W7Q, S11R, M19F, R22T, 94.8 17.8
    K26R, K28R
    NV1G1137 NV1D2974 129 Y1Q, W7Q, S11A, M19P, V20S, 95.7 16.2
    R22T
    NV1G1843 NV1D3432 245 Y1Q, K4E, W7Q, S11R, E17R, 95.9 10.4
    M19F, R22T, K26R
    NV1G1822 NV1D3423 237 Y1Q, W7Q, D10R, S11R, E12R, 99.5 9.45
    M19F, R22T, K26R
    NV1G1862 NV1D3556 296 W7Q, S11A, M19F, V20S, R22T 100 18.5
    NV1G1969 NV1D3795 337 Y1Q, W7Q, S11R, M19F, R22T, 100 14.5
    K26R
    NV1G1980 NV1D3812 353 Y1Q, W7Q, S11R, M19F, R22T, 101 23.6
    K26R
    NV1G1850 NV1D3414 235 Y1Q, W7Q, S11R, M191, R22T, 102 19.4
    K26R, K28S
    NV1G1981 NV1D3815 356 Y1Q, W7Q, S118, M19F, R22T, 102 13.5
    K26R
    NV1G1851 NV1D3390 219 Y1Q, W7Q, S11R, G18R, M19F, 108 15.5
    R22T, K26R
    NV1G1922 NV1D3466 248 Y1Q, W7Q, S11E, M19F, R22T, 108 922
    K26R
    NV1G1778 NV1D3349 181 Y1Q, K4D, W7Q, S11R, M19F, 109 16
    R22T, K26R
    NV1G1972 NV1D3824 361 Y1Q, W7Q, S11R, M19F, R22T, 110 16.1
    K26R
    NV1G1974 NV1D3796 338 Y1Q, W7Q, S11R, M19F, R22T, 110 19.6
    K26R
    NV1G1826 NV1D3357 188 Y1Q, W7Q, T8E, S11R, N119F, 111 15.1
    R22T, K26R
    NV1G1892 NV1D3439 246 Y1Q, W7Q, S11R, M19F, R22T, 112 13.2
    K26R, W30G
    NV1G1819 NV1D3375 204 Y1Q, W7Q, S11R, R13S, M19F, 113 1270
    R22T, K26R
    NV1G1805 NV1D3410 233 Y1Q, W7Q, S11R, M19F, R22T, 114 21.5
    K26R, K28A
    NV1G1831 NV1D3374 203 Y1Q, W7Q, S11R, R13Q, M19F, 114 1600
    R22T, K26R
    NV1G1693 NV1D3512 253 Y1Q, W7Q, S11R, M19F, R22T, 115.6
    K26R
    NV1G1854 NV1D3392 221 Y1Q, W7Q, S11R, G18T, M19F, 117 21.8
    R22T, K26R
    NV1G1951 NV1D3829 365 Y1Q, W7Q, S11R, M19F, R22T, 122 13.3
    K26R
    NV1G1860 NV1D3393 222 Y1Q, W7Q, S11R, G18A, M19F, 125 24.8
    R22T, K26R
    NV1G1099 NV1D2732 36 Y1Q, W7Q, S11A 126 26.9
    NV1G1705 NV1D3513 254 Y1Q, W7Q, S11R, M19F, R22T, 131.2
    K26R
    NV1G1848 NV1D3426 240 Y1Q, W7Q, D10K, S11R, E12K, 135 39.9
    R13D, M19F, R22T, K26R
    NV1G1952 NV1D3813 354 Y1Q, W7Q, S11R, M19F, R22T, 139 30.1
    K26R
    NV1G1631 NV1D3252 164 Y1Q, W7Q, S11A, M19F 145 53
    NV1G1817 NV1D3371 201 Y1Q, W7Q, S11R, R13A, M19F, 151 33.7
    R22T, K26R
    NV1G1789 NV1D3394 223 Y1Q, W7Q, S11R, G18D, M19F, 155 41.4
    R22T, K26R
    NV1G1852 NV1D3391 220 Y1Q, W7Q, S11R, G18K, M19F, 157 23.1
    R22T, K26R
    NV1G1709 NV1D3510 251 Y1Q, W7Q, S11R, M19F, R22T, 159
    K26R
    NV1G1840 NV1D3425 239 Y1Q, W7Q, D10R, S11R, E12R, 161 27.9
    R13D, M19F, R22T, K26R
    NV1G1809 NV1D3413 234 Y1Q, W7Q, S11R, M19F, R22T, 164 43.7
    K26R, K28Q
    NV1G1863 NV1D3356 187 Y1Q, W7Q, T8D, S11R, M19F, 167 32.2
    R22T, K26R
    NV1G1699 NV1D3527 267 Y1Q, W7Q, S11R, M19F, R22T, 169.1
    K26R
    NV1G1844 NV1D3428 242 Y1Q, W7Q, D10K, S11R, E12K, 180 52.4
    R13E, M19F, R22T, K26R
    NV1G1853 NV1D3370 200 Y1Q, W7Q, S11R, R13T, M19F, 181 25.1
    R22T, K26R
    NV1G1946 NV1D3825 362 Y1Q, W7Q, S11R, M19F, R22T, 194 28.4
    K26R
  • The wild-type Protoxin-II inhibits Nav1.7 with an IC50 value of about 4 nM in veratridine-induced depolarization inhibition assay as described in Example 3. Variants retaining significant Nav1.7 potency were characterized further. FIG. 1 shows the sequence genus of generated Protoxin-II variants that inhibit Nav1.7 with an IC50 value of 30 nM or less.
  • Select Protoxin-II variants were tested for their inhibition of Nav1.7 and for their selectivity against human Nav1.6 using QPatch. IC50 values for both Nav1.7 and Nav1.6 for select peptides obtained using QPatch are shown in FIG. 2.
  • The amino acid sequences of the peptides shown in FIG. 2 are shown in FIG. 3. All these peptides had W7Q and M19F substitutions when compared to the wild type Protoxin-II.
  • The Protoxin-II variants were expressed and purified as described in Example 1, or synthesized by standard solid phase synthesis methods. The yields of the recombinant or synthetic peptides were compared to the yields of the wild-type Protoxin-II. Table 12 shows that the yields of the select Protoxin-II variants were significantly higher than that of Protoxin-II, indicating improved folding properties of the variants. The scale of the solid-phase synthesis was 0.5 mmol.
  • TABLE 12
    Recombinant
    Solid phase synthesis expression
    Yield Yield %
    Total from From active
    Peptide yield Crude Linear isomer
    Protoxin-II  52 mg 2.7%  7.3% 54.0%
    NVID2775  84 mg 4.5% 18.7% 89.1.%
    NV1D3034 149 mg 8.0% 21 0% 85.2%
    NV1D3368  83 mg 4.0% 24.0%  93.%
    • EXAMPLE 5 Protoxin-II Variants are Efficacious in In Vivo Models of Pain
  • Materials and Methods
  • Animals Male C5761/6 mice (24-26 g), ordered from Charles River and housed individually, were used for this study.
  • Behavioral Tests
  • Von Frey Test: Mechanical (tactile) threshold was assessed by Von Frey Hairs following the Up-Down method (Dixon, 1980, Chaplan et al., 1994). 7 graded stimuli (von Frey filaments: 0.03, 0.07, 0.16, 0.4, 0.6, 1, 2 g; Stoelting, Wood Dale, IL) were used. Von Frey hairs were presented perpendicularly against the center plantar area (between toris) on a hindpaw. Sufficient force was applied to bend the filament slightly and held for 3 seconds. Per the Chaplan paper, a positive response can be either 1) a sharp withdrawal or 2) immediate flinching upon removal of the filament. See Chaplan et al for more details. Mice were acclimated to the wire mesh in the testing chamber for 30-60 minutes prior to testing.
  • Hargreaves Test: A modified Hargreaves box was used to measure thermal paw withdrawal latency (PWL) (Hargreaves et al., 1988, Pain, 32:77-88; Dirig et al.,1997, J Neurosci. Methods, 76:183-191). This box consists of a chamber with a raised glass floor maintained at a constant temperature (27° C.). The thermal nociceptive stimulus originates from a projection bulb light beam below the glass surface. The light beam is aimed at the area between toris (center plantar). The “start” button will turn on the light and start the timer. Movements (such as a sudden withdrawal) of the stimulated paw will trigger the switch to turn off the light and stop the timer. The latency in seconds is displayed. If no movement occurs, the bulb will be turned off after 20 seconds (cutoff) to prevent tissue injury. The animals were allowed to habituate on the glass surface for 30-60 minutes before PWL measurement. Constant amperage was used throughout the study, which resulted in Pre-test paw withdrawal latencies between 8-12 seconds when averaged over 3 to 6 read-outs taken at least 5 minutes apart.
  • MPE % Calculation: Percent maximum possible effect (MPE %)=(T1−T0)/(Tc−T0)×100%. T0: threshold on day 0 (post-CFA, pre-pump); threshold on day I post pump implantation; Tc: cut-off of the test (20 s for the Hargreaves test and 2 g for the Von Frey test).
  • Hotplate Test: Animals were placed on a 10″×10″ metal plate surrounded by 4 Plexiglas walls (15 inches high). The plate was maintained at a temperature of either 50 or 55° C. The response latency (time when the animal first flinches or licks its hind paw, jumps, or vocalizes) was measured and the animal removed from the plate. Animals showing no response were removed from the plate after 40 s (50° C.) or 20 s (55° C.) to prevent any possible tissue damage. This trial was repeated 2-5 times every 15-60 minutes in a day.
  • Inflammatory Pain Models
  • CFA Model: Animals were anesthetized with isoflurane (4% induction and 2% maintenance) and 20 μL of 100% Complete Freund's Adjuvant (CFA; Sigma-Aldrich; Saint Louis, Mo.) was injected into the center plantar area on one hind paw using a 27 gauge needle attached to a 50 μL Hamilton syringe.
  • Carrageenan model: Animals were anesthetized with isoflurane (4% induction and 2% maintenance) and 25 μL of 2% Acarrageenan (Sigma-Aldrich; Saint Louis, Mo.) dissolved in normal saline was injected into the center plantar area on hind paws using an insulin syringe (BD; Franklin Lakes, N.J.).
  • Implantation of Mini Pumps
  • Alzet micro-osmotic mini pumps (Durect Corporation Model 1003D and 2001D) were filled and primed per manufacturer's guide. Mice were anesthetized with isoflurane (5% induction; 2% maintenance). Their backs were shaved, wiped down with isopropyl alcohol and povidone iodine, and a small incision was made between the scapulae. Using a pair of forceps or hemostat, a small pocket was formed by spreading the subcutaneous connective tissues apart. The pump was inserted into the pocket with the flow moderator pointing away from the incision. The skin incision was then closed using 7 mm staples and the animals were allowed to recover in their home cages.
  • Data Analysis
  • Data are represented as mean±s.e.m. Prism (Graphpad Software Inc., La Jolla, Calif.) was used for graphing and statistical analysis. For comparison of threshold values over time, a two-way ANOVA followed by Bonferroni's multiple comparison test was used with a significance level of p<0.05. Hotplate and MPE % data were analyzed by one-way ANOVA followed by Bonferroni's multiple comparison test.
  • Results
  • Efficacy of variants NV1D3034-OH (NV1D3034-COOH), NV1D3368-OH (NV1D3368-COOH) and NV1D2775-OH (NV1D2775-COOH) was studied in the CFA model, a commonly used model of inflammatory pain. The injection of CFA in the hindpaw induced paw edema (not shown) and hypersensitivity to thermal stimuli (thermal hyperalgesia), as indicated by the lowered thermal latency in the injected paw on day 0 (FIG. 6A). Thermal hyperalgesia was completely reversed by NV1D3034-OH at 684 and 1824 μg/day, when administered by a subcutaneous osmotic mini-pump (FIGS. 4A and 4B).
  • NV1D3368-OH fully reversed CFA-induced thermal hyperalgesia at 684 and 1824 μg/day (FIGS. 5A and 5B). NV1D2775-OH demonstrated strong efficacy in the CFA model. Thermal latencies reached values close to the cut-off following NV1D2775 administration (FIGS. 6A and 6B, 1824 μg/day), suggesting a strong analgesia effect on top of the anti-hyperalgesia effect. In addition, NV1D2775-OH reversed CFA-induced tactile allodynia (FIGS. 6C and 6D, 1824 μg/day). The anti-hyperalgesic effect of NV1D2775-OH was seen as early as 4 hr post-pump implantation (FIG. 7A). The effect reached the maximum at 8 hr in both the thermal and tactile tests (FIGS. 7A and 7B), which was maintained at 24 hr. Thermal latency and tactile threshold returned to the control level by 48 h post pump implantation (approximately 24 h after the pumps were predicted to be empty) (FIGS. 7A and 7B).
  • CFA-induced thermal hyperalgesia was readily reversed by two additional peptides, NV1D3368-amide (NV1D3368-NH2) and NV1D3034-N-methylamide (NV1D3034-NHMe). Thermal MPE % from the experiments is summarized in Table 13.
  • TABLE 13
    Dose (μg/day/mouse)
    Vehicle
    Peptide (PBS) 228 684 1824
    NV1D3034-OH 20 ± 7 (11) 2.72 ± 6 (6) 48 ± 10* (8) 50 ± 6* (8)
    NV1D3368-OH 13 ± 7 (8)    23 ± 8 (7) 42 ± 9* (7)   47 ± 6** (8)
    NV1D2775-OH 15 ± 4 (20)   35 ± 8 (8) 57 ± 12***  85 ± 6****
    (8) (3.2)
    NV1D3368-NH 2 15 ± 13 (6)   27 ± 4 (4) 46 ± 9 (4)   55 ± 15 (6)
    NV1D3034-  5 ± 25 (3) 49 ± 17 (6)
    NHMe
    *P <0.05, **P <0.01, ***P <0.001 and ****P <0.0001 vs. PBS, one-way ANOVA followed by Bonfroni’s multiple comparison.
  • NV1D2775-OH also exhibited strong, dose-dependent efficacy in the hotplate test (FIG. 8). Latencies at 50 and 55° C. reached values near cut-off following the administration of 1824 μg/day. At 228 μg/day, NV1D2775-OH produced a modest yet significant increase in the thermal latency, compared to the PBS control.
  • The efficacy of NV1D2775-OH was evaluated in another model of inflammatory pain, the carrageenan model. Animals were implanted with NV1D2775-OH or PBS pumps. Thermal withdrawal latencies were measured pre-and on day I post-pump. A-carrageenan was injected into the hindpaws and thermal latencies were measured again on 2, 3 and 4 hr following carrageenan. NV1D2775-OH at 1824 μg/day produced significant analgesia (FIG. 9). Injection of A-carrageenan in the hindpaws induced inflammation (not shown) and lowered thermal paw withdrawal latency in the Hargreaves test over the 4 hr test-period (FIG. 9, PBS group). Animals pretreated with NV1D2775-OH at 1824 μg/day were fully protected from carrageenan-induced hyperalgesia.
    • EXAMPLE 6 Generation and Characterization of Combinatorial Protoxin-II Variants
  • An amino acid scanning library was generated for Protoxin-II. At every non-cysteine position in Protoxin-II (Tyr1, Gln3, Lys4, Trp5, Met6, Trp7, Thr8, Asp10, Ser11, G1u12, Arg13, Lys14, G1u17, G1y18, Met19, Va120, Arg22, Leu23, Trp24, Lys26, Lys27, Lys28, Leu29 and Trp30) the following residues were substituted in place of the native residue: Ala, Asp, Glu, Phe, Gly, His, Ile, Lys, Leu, Asn, Pro, Gin, Arg, Ser, Thr, Val, and Tyr.
  • Mutant peptides were expressed as recombinant fusions to human serum albumin and site-specifically enzymatically cleaved using HRV3C to generate Protoxin-II variants as described in Example 1. Each Protoxin-II variant, after cleavage from HSA had a residual N-terminal GP from the cleavage site. For each Protoxin-II variant, IC50 values against human Nav1.7 were measured using veratridine-induced depolarization inhibition assay or Qpatch according to the protocols described in Example 3. Variants demonstrating IC50≤100 nM for human Nav1.7 were counter-screened for selectivity against additional hNav channels using Qpatch electrophysiology. Selective hits were identified and used in the design of combinatorial peptide libraries which were produced using both recombinant expression and solid-phase peptide synthesis. Combinatorial variants were screened using the same strategy as detailed above.
  • Based on the results, positions that can be mutated to improve selectivity include Gln3, Ser11, Glu12, Lys14, Glu17, Gly18, Leu29 and Trp30 (residues numbering according to SEQ ID NO: 1).
  • The solution structure of Protoxin-II was determined by NMR and is shown in FIG. 10 as a surface representation. The left hand side of the Figure shows the previously described (Park et al., J. Med. Chem. 2014, 57:6623-6631) ring of Trp residues, W5/W7/W24, surrounding M6. On the opposite side of the molecule, using both mutagenesis and the NMR structure, a selectivity face was identified in this study on Protoxin-II consisting of multiple amino acid positions which can be mutated to improve selectivity for hNav1.7 over other sodium channel isoforms. The residues residing on the selectivity face include residues Ser11, Glu12, Lys14, Glu17, Gly18, Leu29 and Trp30 (residue numbering according to SEQ ID NO: 1). The identification of the selectivity face and multiple positions within responsible for selectivity towards Nav1.7 has not been described earlier.
  • Improved selectivity of Protoxin II variants with substitution at Ser11 is unexpected as it has been earlier demonstrated that mutation of Ser11 affect activity on multiple Nav channels, and therefore the residue was concluded not to play a role in Protoxin-II Nav1.7 selectivity (Park et al., J. Med. Chem. 2014, 57:6623-6631).
  • A key step in the synthetic production of Protoxin-II variants is the oxidative refolding of the linear peptide, where the disulfide pairings are formed. The RP-HPLC trace for native Protoxin-II purification following refolding revealed multiple peaks at differing retention times that were of correct mass but demonstrated differing levels of activity, indicative of a mixture of properly and improperly folded isomers of the peptide.
  • The relative abundance of the RP-HPLC major peak, and therefore the relative abundance of correctly folded peptide could be improved by making substitutions at various Protoxin-II positions. Mutation of Trp7 or Trp30 improved folding of the resulting Protoxin-II variant. Mutation of both Trp7 and Trp30 in combination further improved folding of the resulting Protoxin-II variant, and could rescue folding of difficult-to-refold Protoxin-II variants.
  • Production of combinatorial mutant peptides having one or more substitutions that improved selectivity (Gln3, Ser11, Glu12, Lys14, Glu17, Gly18, and Leu29) as well as mutations at Trp7 and Trp30 resulted in peptides with both improved selectivity and improved refolding properties. Protoxin-II belongs to a family 3 of inhibitory cysteine knot peptides (Klint et. al., Toxicon 60:478-491, 2012). Trp7 is conserved in all family 3 members, and substitutions at this position as well as at Trp5 and Met6 in Jingzhaotoxin-V, another family 3 inhibitory cysteine knot peptide, resulted in loss in potency, indicating that hydrophobic residues at positions 5, 6 and 7 in Jingzhaotoxin-V are essential to Jingzhaotoxin-V Nav1.7 inhibitory potency (Int. Pat. Publ. No. 2014/165277). Trp5/Met6/Trp7 is also conserved in Protoxin-II, and therefore it was unexpected that polar substitutions at Trp7 can be made without loss of Protoxin-II activity with significantly improved refolding properties. Substitutions at Trp30 were shown to simultaneously improve Nav1.7 selectivity and refolding properties of the variant peptide and were unexpected since individual advantageous substitutions typically only improve a single parameter.
  • Table 14 shows the amino acid sequences of the select generated Protoxin-II variants.
  • TABLE 14
    Protein Protein
    Name Substitution SEQ ID NO: Amino acid sequence
    NV1G2232 W30L 408 GPYCQKWMWTCDSERKCCEGMVCR
    LWCKKKLL-COOH
    NV1G2182 W30F 409 GPYCQKWMWTCDSERKCCEGMVCR
    LWCKKKLF-COOH
    NV1D2319 W30Y 410 GPYCQKWMWTCDSERKCCEGMVCR
    LWCKKKLY-COOH
    NV1G2329 W30G 411 GPYCQKWMWTCDSERKCCEGMVCR
    LWCKKKLG-COOH
    NV1G2129 W30I 412 GPYCQKWMWTCDSERKCCEGMVCR
    LWCKKKLI-COOH
    NV1G2291 W30V 413 GPYCQKWMWTCDSERKCCEGMVCR
    LWCKKKLV-COOH
    NV1D2156 W7Y 414 GPYCQKWMYTCDSERKCCEGMVCRL
    WCKKKLW-COOH
    NV1G2082 W7E 415 GPYCQKWMETCDSERKCCEGMVCRL
    WCKKKLW-COOH
    63930841 W7Q 416 GPYCQKWMQTCDSERKCCEGMVCRL
    WCKKKLW-COOH
    64087946 (−GP) 417 YCQKWMQTCDAERKCCEGFSC-(N-
    W7Q, S11A, M19F, Me-Arg)-LWCKKKLL-COOH
    V20S, R22Me, W30L
    64053366 (−GP) W7Q S11D 418 YCQKWMQTCDDERKCCEGMVCRLW
    W30L CKKKLL-COOH
    64053340 (−GP) W7Q K14F 419 YCQKWMQTCDSERFCCEGMVCRLW
    W30L CKKKLL-COOH
    64053236 W7Q K14F W30L 420 GPYCQKWMQTCDSERFCCEGMVCRL
    WCKKKLL-COOH
    64053223 W7Q S11I W30L 421 GPYCQKWMQTCDIERKCCEGMVCRL
    WCKKKLL-COOH
    63955918 W7Q W30L 422 GPYCQKWMQTCDSERKCCEGMVCRL
    WCKKKLL-COOH
    64053210 W7Q El7N W30L 423 GPYCQKWMQTCDSERKCCNGMVCRL
    WCKKKLL-COOH
    64087907 (−GP) W7Q 424 YCQKWMQTCDSERKCCEGMVCRLW
    CKKKLW-COOH
    64032488 (−GP) W7Q W30L 425 YCQKWMQTCDSERKCCEGMVCRLW
    CKKKLL-COOH
    64053301 W7Q S11V W30L 426 GPYCQKWMQTCDVERKCCEGMVCRL
    WCKKKLL-COOH
    64053275 W7Q E17L W30L 427 GPYCQKWMQTCDSERKCCLGMVCRL
    WCKKKLL-COOH
    64053327 (−GP) W7Q E17N 428 YCQKWMQTCDSERKCCNGMVCRLW
    W30L CKKKLL-COOH
    NV1G2324 E17Y 429 GPYCQKWMWTCDSERKCCYGMVCR
    LWCKKKLW-COOH
    NV1G2094 E17I 430 GPYCQKWMWTCDSERKCCIGMVCRL
    WCKKKLW-COOH
    NV1G1996 E17L 431 GPYCQKWMWTCDSERKCCLGMVCRL
    WCKKKLW-COOH
  • Select variants were characterized for their inhibition of Nav1.7 using veratridine-induced depolarization inhibition assay or Qpatch as described in Example 3. Table 15 shows the IC50 values obtained. For some variants, only % inhibition (% blk; percent block of control) at a single concentration (10 nM or 30 nM) was recorded for Qpatch.
  • TABLE 15
    hNav1.7
    Veratridine-induced
    Protein Depolarization QP
    Protein SEQ ID inhibition Assay IC50
    Name NO: IC50 (nM) se* (nM) % blk** se*
    NV1G2232 408 16.7 1.32 5.0 56.5% @ 5.7
    10 nM
    NV1G2182 409 17.3 1.37 3.8 54.2% @ 5.4
    10 nM
    NV1G2319 410 20.7 2.3 9.7 43.2% @ 6.2
    10 nM
    NV1G2329 411 38 2.43E+00
    NV1G2129 412 47.3 3.81 −6.5% @ 6.5
    10 nM
    NV1G2291 413 63.3 14.9
    NV1G2156 414 90.5 6.88
    NV1G2082 415 90.8 11.4
    63930841 416 20.9
    64087946 417 23.8 20.7% @ 10.9 
    10 nM
    64053366 418 22.1% @ 3.5
    10 nM
    64053340 419 26.8% @ 3.7
    10 nM
    64053236 420 28.0% @ 13.2 
    10 nM
    64053223 421 33.0% @ 5.8
    10 nM
    63955918 422 10.8 38.50% @  4.5
    10 nM
    64053210 423 41.7% @ 6.2
    10 nM
    64087907 424 7.1 45.1% @ 6.0
    10 nM
    64032488 425 6.5 45.6% @ 4.6
    10 nM
    64053301 426 10.7 45.83% @  3.3
    10 nM
    64053275 427 2.9 48.22% @  5.2
    10 nM
    64053327 428 7.9 51.9% @ 2.6
    10 nM
    NV1G2324 429 57.5% @ 3.9
    10 nM
    NV1G2094 430 63.2 % @ 6.2
    30 nM
    NV1G1996 431 0.5 76.9% @ 2.3
    10 nM
    *se; standard error
    **blk: % block
    QP: QPatch
  • Select variants were tested against various human Navl.x channels. Table 16 shows the results of those experiments. IC50 values for each channel were measured using QPatch.
  • TABLE 16
    Protein
    Protein SEQ ID IC50 (nM)
    Name Substitution NO: Nav1.1 Nav1.2 Nav1.4 Nav1.6
    NV1G2232 W30L 408 3847.0 562.7
    NV1G2182 W30F 409 239.6 732.2 253.1
    NV1G2319 W30Y 410 1704.0
    63930841 W7Q 416 543.1
    64087946 (-GP) 417 2586.0
    W7Q, S11A, M19F,
    V20S, R22Me, W30L
    63955918 W7Q, W30L 422 1951.0 17000.0 1987.0
    64087907 (-GP) W7Q 424 1460.0
    64032488 (-GP) W7Q 425 1336.0 1842.0
    W30L
    64053301 W7Q, S11V 426 15340.0 19350.0 2244.0
    W30L
    64053275 W7Q, E17L 427 3868.0 136.7 2219.0
    W30L
    64053327 (-GP) W7Q 428 6391.0 6656.0 3867.0
    E17N W30L
  • Protoxin-II variants were expressed and purified as described in Example 1, or synthesized by standard solid phase synthesis methods. The yields of the recombinant or synthetic peptides were compared to the yields of the wild-type Protoxin-II. Table 17 shows that the yields of the select Protoxin-II variants were significantly higher than that of Protoxin-II, indicating improved folding properties of the variants. The scale of the solid-phase synthesis was 0.1 mmol.
  • TABLE 17
    total
    Protein name Substitution yield (mg)
    NV1D12 3.8
    (Protoxin-II
    with N-
    terminal GP)
    63930841 W7Q 14.4 
    NV1G2232 W30L 14.5 
    63955918 W7Q, W30L 16.2 
    NV1G1996 E17L 1.8
    64053275 E17L W7Q 13.0 
    W30L
    • EXAMPLE 7 Protoxin-II Variants are Efficacious in In Vivo Models of Pain Following Intrathecal Administration
  • Efficacy of select Protoxin-II variants in reducing pain after intrathecal administration was evaluated. Peptides NV1D2775-OH, NV1D3034 and 63955918 were used in the studies. Animal models that measure acute thermal pain (tail flick and hot plate) and injury-induced pain (formalin flinching) were used.
  • Tail-flick test: The animals were placed on a tail-flick device (Ugo Basile). The device has a focal infrared light heating area (diameter-5 mm). The tail (⅓-½ way from distal end) of the animal was placed on the focal heating area. The temperature of the heat source was adjusted to elicit a tail-flick within 10 seconds in animals treated with vehicle. A 15 second cut-off time was used to prevent tissue damage, as is standard in the literature. The time elapsed between the start of the heat stimulus and any avoidance response was measured automatically and recorded for the test groups.
  • Hot plate test: Animals were placed on a 10″×10″ metal plate surrounded by 4 Plexiglas walls (15 inches high). The plate was maintained at a temperature of 52.5° C. The response latency (time when the animal first flinches or licks its hind paw, jumps, or vocalizes) was measured and the animal removed from the plate. Animals showing no response were removed from the plate after 30 s to prevent any possible tissue damage.
  • Formalin Flinching: Formalin-induced pain behavior (i.e. paw flinches) was measured using an automated “flinch response” measuring device manufactured by UCSD. The device detects any sudden movement of a metal band glued onto one hind paw of the animal using a motion sensor installed underneath the device floor. One-half to one hour prior to formalin injection, a small metal band was attached to the plantar surface of one hind paw using a small drop of cyanoacrylate and the animal was placed in the testing chamber to be acclimatized. Formalin (2.5%, 50 μL) was injected subcutaneously into the dorsum of the paw with the metal band. The animal was placed in the customized cylinder (25×10×20 cm, San Diego Instrument) immediately after intraplantar formalin injection. Paw flinches were recorded automatically.
  • In the acute thermal pain models, Protoxin-II variant 63955918 produced potent and prolonged analgesia as indicated by the elevated latency in the tail flick test (FIG. 11A and FIG. 11B) and hot plate test (FIG. 11C, FIG. 11D) after a single intrathecal administration. The significance and duration of the analgesia was dose-dependent.
  • Hindpaw formalin injection is a commonly used model for injury-induced pain. The injection induces a characteristic, bi-phasic flinching behavior, which indicates pain in test animals. As shown in FIG. 11E, animals pretreated with intrathecal injection of Protoxin-II variant 63955918 demonstrated fewer flinches in the formalin test, suggesting an inhibition of injury-induced pain.
  • Similarly, peptides NV1D2775-OH and NV1D3034 demonstrated significant efficacy in the tail flick, hot plate and formalin test (FIG. 12A, FIG. 12B, FIG. 12C, FIG. 12D, FIG. 12E, FIG. 13A, FIG. 13B, FIG. 13C, FIG. 13D, FIG. 13E) following a single intrathecal administration.
    • EXAMPLE 8 Characterization of Additional Protoxin-II Variants
  • Additional Protoxin-II variants were designed and expressed using the strategies and methods described in Example 6, and characterized in FLPR Tetra and/or Qpatch according to the protocols described in Example 3.
  • Table 18 shows the amino acid sequence of the select generated Protoxin-II variants.
  • TABLE 18
    ID Mutation SEQ ID NO: Sequence
    NV1G2228 E12R 434 GPYCQKWMWTCDSRRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2072 E12T 435 GPYCQKWMWTCDSTRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2008 S11N 436 GPYCQKWMWTCDNERKCCEGMVCRLWCKK
    KLW-COQH
    NV1G1994 T8F 437 GPYCQKWMWFCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2070 S11T 438 GPYCQKWMWTCDTERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2074 Y1N 439 GPNCQKWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2079 E17A 440 GPYCQKWMWTCDSERKCCAGMVCRLWCKK
    KLW-COOH
    NV1G2073 E17D 441 GPYCQKWMWTCDSERKCCDGMVCRLWCKK
    KLW-COOH
    NV1G2076 Y1I 442 GPICQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1864 Y1S, W7Q, 443 GPSCQKWMQTCDIRRKCCEGFSCRLWCKKKL
    S11I S11I, E12R, W-COOH
    M19F, V20S
    NV1G2039 S11I 444 GPYCQKWMWTCDIERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1007 Y1Q, W7Q, 445 GPQCQKWMQTCDAERKCCEGFVCRLWCKKK
    W30tryptophanol S11A, M19F, L-(tryptophanol)
    C-terminal
    alcohol
    NV1G2238 K14P 446 GPYCQKWMWTCDSERPCCEGMVCRLWCKKK
    LW-COOH
    NV1G2198 Y1K 447 GPKCQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2195 E12V 448 GPYCQKWMWTCDSVRKCCEGMVCRLWCKK
    KLW-COOH
    NV1G1153-N- Y1Q, W7Q, 449 GPQCQKWMQTCDRERKCCEGFVCTLWCRKKL
    methyl S11R, M19F, W-(methylamide)
    R22T, K26R,
    C-terminal
    methylamide
    NV1G2007 S11L 450 GPYCQKWMWTCDLERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2140 E17P 451 GPYCQKWMWTCDSERKCCPGCMVCRLWCKKK
    LW-COOH
    NV1G2003 T8Y 452 GPYCQKWMWYCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2236 Y1L 453 GPLCQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2164 Y1V 454 GPVCQKWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G1864 Y1S, W7Q, 455 GPSCQKWMQTCDARRKCCLGFSCRLWCKKKL
    E17L S11A, E12R, W-COOH
    E17L, V20S
    (−GP) (−GP) 109 SCQKWMQTCDAERKCCEGFVCRLWCKKKLW-
    NV1G1001 Y1S, W7Q, COOH
    S11A, M19F
    NV1G2149 T8L 456 GPYCQKWMWLCDSERKCCEGMVCRIWCKKK
    LW-COOH
    NV1G2226 V20I 457 GPYCQKWMWTCDSERKCCEGMICRLWCKKK
    LW-COOH
    NV1G2286 T8K 458 GPYCQKWMWKCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2128 E12H 459 GPYCQKWMWTCDSHRKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2041 K4E, E17R 460 GPYCQEWMWTCDSERKCCRGMVCRLWCKKK
    LW-COOH
    NV1G2001 T8G 461 GPYCQKWMWGCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2019 K4E, W5F, 462 GPYCQEFLWTCDSTRKCCEGMVCRLWCKKKL
    M6L, E12T W-COOH
    NV1G2002 K14H 463 GPYCQKWMWTCDSERHCCEGMVCRLWCKK
    KLW-COOH
    NV1G2225 E17R 464 GPYCQKWMWTCDSERKCCRGMVCRLWCKKK
    LW-COOH
    NV1G2012 K14V 465 GPYCQKWMWTCDSERVCCEGMVCRLWCKKK
    LW-COOH
    NV1G2020 Y1S, M6F, 466 GPSCQKWFWTCDRTRKCCEGLVCRLWCKKKL
    A11R, E12T, W-COOH
    Ml9L
    NV1G2334 E17K 467 GPYCQKWMWTCDSERKCCKGMVCRLWCKKK
    LW-COOH
    NV1G2025 Y1Q, W7Q 468 GPQCQKWMQTCDATRKCCEGFVCRLWCKKK
    S11A, E12T, LW-COOH
    M19F
    NV1G2131 E12Y 469 GPYCQKWMWTCDSYRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1007 Y1Q, W7Q, 470 GPQCQKWMQTCDITRKCCEGFVCRLWCKKKL
    A11I, E12T S11I, E12T W-COOH
    M19F
    NV1G2268 Y1F 471 GPFCQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2332 E17S 472 GPYCQKWMWTCDSERKCCSGMVCRLWCKKK
    LW-COOH
    NV1G2010 T8V 473 GPYCQKWMWVCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2053 Y1T 474 GPTCQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1519 Y1Q, W7Q, 133 GPQCQKWMQTCDARRKCCEGFVCRLWCKKK
    [S11I]] LW-COOH
    S11A, E12R,
    M19F
    NV1G2253 E12I 475 GPYCQKWMWTCDSIRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2055 E12L 476 GPYCQKWMWTCDSLRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2338 K4R 477 GPYCQRWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2030 K14F 478 GPYCQKWMWTCDSERFCCEGMVCRLWCKKK
    LW-COOH
    NV1D2024 Y1S, M6F, 479 GPSCQKWFWTCDANRKCCEGLVCRLWCKKKL
    S11A, E12N, W-COOH
    M19L
    NV1G2004 K14Y 480 GPYCQKWMWTCDSERYCCEGMVCRLWCKKK
    LW-COOH
    NV1G2336 M6L 481 GPYCQKWLWTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2011 E17F 482 GPYCQKWMWTCDSERKCCFGMVCRLWCKKK
    LW-COOH
    NV1G2080 W5Y 483 GPYCQKYMWTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2288 D10R 484 GPVCQKWMWTCRSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2142 K14R 485 GPYCQKWMWTCDSERRCCEGMVCRLWCKKK
    LW-COOH
    NV1G2232 W30L 408 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LL-COOH
    NV1G2193 E12D 486 GPYCQKWMWTCDSDRKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2230 S11D 487 GPYCQKWMWTCDDERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2182 W30F 409 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LF-COOH
    NV1G1153 Y1Q, W7Q, 488 GPQCQKWMQTCDRERKCCEGFVCTLWCRKKL
    C-terminal S11R, M19F, W-(palmitoyl-lysine)-COOH
    palmitoyl- R22T, K26R,
    lysine addition
    of
    palmitoyl-
    lysine at
    position 33
    NV1G2339 T8A 489 GPYCQKWMWACDSERKCCEGWMCRLWCKK
    KLW-COOH
    NV1G2016 Y1S, M6F, 490 GPSCQKWFWTCDRERKCCEGLVCRLWCKKKL
    S11R, M19L W-COOH
    NV1G2017 Y1Q, K4E, 491 GPQCQEFLWTCDSERKCCEGMVCRLWCKKKL
    W5F, M6L W-COOH
    NV1G2111 E17N 492 GPYCQKWMWTCDSERKCCNGMVCRLWCKK
    KLW-COOH
    NV1G2330 R22S 493 GPYCQKWMWTCDSERKCCEGMVCSLWCKKK
    LW-COOH
    NV1G2204 E17T 494 GPYCQKWMWTCDSERKCCTGMVCRLWCKK
    LW-COOH
    NV1G2026 Y1S, M6E, 495 GPSCQKWFWTCDATRKCCEGLVCRLWCKKKL
    S11A, E12T, W-COOH
    M19L
    NV1G1007 Y10, W7Q, 496 GPQCQKWMQTCDAERKCCEGFVCRLWCKKK
    with S11A, M19F, LWGGGGG-COOH
    C-terminal addition
    5xGly of 5xGly at
    positions
    31-35
    NV1G2038 L23F 497 GPYCQKWMWTCDSERKCCEGMVCRFWCKKK
    LW-COOH
    NV1G2305 R22H 498 GPYCQKWMWTCDSERKCCEGMVCHLWCKK
    KLW-COOH
    NV1G2021 K4E, W5F, 499 GPYCQEFLWTCDRTRKCCEGMVCRLWCKKKL
    M6L, S11R, W-COOH
    EL2T
    NV1G2319 W30Y 410 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LY-COOH
    NV1G2100 E12G 500 GPYCQKWMWTCDSGRKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2130 Y1D 501 GPDCQKWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2081 K4D 502 GPYCQDWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2252 T8H 503 GPYCQKWMWHCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2040 K26Y 504 GPYCQKWMWTCDSERKCCEGMVCRLWCYKK
    LW-COOH
    NV1G2146 G18P 505 GPYCQKWMWTCDSERKCCEPMVCRLWCKKK
    LW-COOH
    NV1G1153-N- Y1Q, W7Q, 506 GPQCQKWMQTCDRERKCCEGFVCTLWCRKKL
    ethyl S11R, M19F, W-(ethylamide)
    R22T, K26R,
    C-teminal
    ethylamide
    NV1G2098 E17H 507 GPYCQKWCMWTCDSERKCCHGMVCRLWCKK
    KLW-COOH
    NV1G2191 L29H 508 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    HW-COOH
    NV1G2333 G18K 509 GPYCQKWMWTCDSERKCCEKMVCRLWCKKK
    LW-COOH
    NV1G2224 K14S 510 GPYCQKWMWTCDSERSCCEGMVCRLWCKKK
    LW-COOH
    NV1G1001-N- (−GP) 511 SCQKWMQTCDAERKCCEGFVCRLWCKKKLW-
    ethyl Y1S, W7Q, (ethylamide)
    S11A, M19P,
    C-terminal
    ethylamide
    NV1G1996 E17L 431 GPYCQKWMWTCDSERKCCLGMVCRLWCKKK
    LW-COOH
    NV1G2337 K14Q 512 GPYCQKWMWTCDSERQCCEGMVCRLWCKK
    KLW-COOH
    NV1G2301 V20T 513 GPYCQKWMWTCDSERKCCEGMTCRLWCKKK
    LW-COOH
    NV1G2075 K4T 514 GPYCQTWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2278 R22N 515 GPYCQKWMWTCDSERKCCEGMVCNLWCKK
    KLW-COOH
    NV1G2014 W24H 516 GPYCQKWMWTCDSERKCCEGMVCRLHCKKK
    LW-COOH
    NV1G2065 Y1Q, W7Q, 517 GPQCQKWMQTCDRTRKCCEGFVCRLWCKKKL
    S11R, E12T, W-COOH
    M19F
    NV1G2099 L29V 518 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    VW-COOH
    NV1G1007 Y1Q, W7Q, 519 GPQCQKWMQTCDAERKCCLGFVCRLWCKKKL
    E17L S11A, E17L, W-COOH
    M19F
    NV1G1007 Y1Q, W7Q, 520 GPQCQKWMQTCDAERKCCEGFVCRLWCKKK
    G33 S11A, M19F, LWG-COOH
    addition
    of Gly at
    position 33
    1007 A11I Y1Q, W7Q, 521 GPQCQKWMQTCDIERKCCEGFVCRLWCKKKL
    S11I, M19F W-COOH
    NV1G2221 K27A 522 GPYCQKWMWTCDSERKCCEGMVCRLWCKAK
    LW-COOH
    NV1G2097 K14I 523 GPYCQKWMWTCDSERICCEGMVCRLWCKKK
    LW-COOH
    NV1G2029 W5L 524 GPYCQKLMWTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2257 S11V 525 GPYCQKWMWTCDVERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G1998 V20H 526 GPYCQKWMWTCDSERKCCEGMHCRLWCKKK
    LW-COOH
    NV1G2068 R13Y 527 GPYCQKWMWTCDSEYKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1001 Y1S, W7Q, 65 GPSCQKWMQTCDAERKCCEGFVCRLWCKKKL
    S11A, M19F W-COOH
    NV1G2137 V0K 528 GPYCQKWMWTCDSERKCCEGMKCHLWCKKK
    LW-COOH
    NV1G2199 S11H 529 GPYCQKWMWTCDHERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2300 K27G 530 GPYCQKWMWTCDSERKCCEGMVCRLWCKG
    KLW-COOH
    NV1G2124 R13H 531 GPYCQKWMWTCDSEHKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2254 T8P 532 GPYCQKWMWPCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2239 K4N 533 GPYCQNWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2255 K4E, E17K 534 GPYCQEWMWTCDSERKCCKGMVCRLWCKKK
    LW-COOH
    NV1G2256 K14G 535 GPYCQKWMWTCDSERGCCEGMVCRLWCKK
    KLW-COOH
    NV1G2095 K14T 536 GPYCQKWMWTCDSERTCCEGMVCRLWCKKK
    LW-COOH
    NV1G2220 L29S 537 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    SW-COOH
    NV1G2154 T8Q 538 GPYCQKWMWQCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2329 W30G 411 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LG-COOH
    NV1G2122 R13K 539 GPYCQKWMWTCDSEKKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1007 Y1Q W7Q, 540 GPQCQKWMQTCDAERKCCEGPVCRLWCKKK
    C-terminal S11A, M19F, LW-(palmitoyl-lysine)-COOH
    palmitoyl- addition
    lysine of
    palmitoyl-
    lysine at
    position 33
    NV1G2000 R22Y 541 GPYCQKWMWTCDSERKCCEGMVCYLWCKKK
    LW-COOH
    NV1G2009 G18Y 542 GPYCQKWMWTCDSERKCCEYMVCRLWCKKK
    LW-COOH
    NV1G2066 K4E, W5F, 543 GPYCQEFLWTCDSERKCCEGMVCRLWCRKKL
    M6L, K26R W-COOH
    NV1G2083 W7S 544 GPYCQKWMSTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2126 K4G 545 GPYCQGWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2043 (−GP) 370 GPCRTIGPSVCQCQKWMQTCDRERKCCEGFV
    Y1Q, W7Q, CTLWCRKKLW-COOH
    S11R, M19F,
    R22T, K26R +
    N-term
    GPCRTIGPS
    VC
    NV1G2050 W7R 546 GPYCQKWMRTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2071 K26T 547 GPYCQKWMWTCDSERKCCEGMVCRLWCTKK
    LW-COOH
    NV1G2129 W30I 412 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LI-COOH
    NV1G2086 R22V 548 GPYCOKWMWTCDSERKCCEGMVCVLWCKKK
    LW-COOH
    NV1G2057 Y1Q, W7Q, 341 GPQCQKWMQTCDRERKCCEGFVCTLWCRKKL
    S11R, M19F, WGSAPAPAPAPAPGSCCNCSSKWCRDHSRCC-
    R22T, K26R + COOH
    C-term
    GSAPAPAP
    APAPGSCC
    NCSSKWCR
    DHSRCC
    NV1G2093 V20E 549 GPYCQKWMWTCDSERKCCEGMECRLWCKKK
    LW-COOH
    NV1G1995 D10F 550 GPYCQKWMWTCFSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2312 K27H 551 GPYCQKWMWTCDSERKCCEGMVCRLWCKH
    KLW-COOH
    NV1G2176 K4S 552 GPYCQSWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2046 K28N 553 GPYCQKWMWTCDSERKCCEGMVCRLWCKK
    NLW-COOH
    NV1G2047 W5E 554 GPYCQKEMWTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2170 V20R 555 GPYCQKWMWTCDSERKCCEGMRCRLWCKKK
    LW-COOH
    NV1G2042 T8E 556 GPYCQKWMWECDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2117 K14E 557 GPYCQKWMWTCDSERECCEGMVCRLWCKKK
    LW-COOH
    NV1G1999 R22G 558 GPYCQKWMWTCDSERKCCEGMVCGLWCKK
    KLW-COOH
    NV1G2247 K28V 559 GPYCQKWMWTCDSERKCCEGMVCRLWCKKV
    LW-COOH
    NV1G2054 D10R, E12R 560 GPYCQKWMWTCRSRRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1007 Y1Q, W7Q, 561 GPQCQKWMQTCDAERKCCFGFVCRLWCKKK
    E17F S11A, E17F, LW-COOH
    M19F
    NV1G2056 D10V 562 GPYCQKWMWTCVSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1007 Y1Q, W7Q, 563 GPQCQKWMQTCD[[R]] A RKCCEGFVCTLWC
    D33 S11A, M19F, RKKLWD-COOH
    addition
    of D at
    position 33
    NV1G2291 W30V 413 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LV-COOH
    NV1G2306 K26S 564 GPYCQKWMWTCDSERKCCEGMVCRLWCSKK
    LW-COOH
    NV1G2023 Y1S, M6F, 565 GPSCQKWFWTCDAERKCCEGLVCRLWCRKKL
    SV11A, M19L, W-COOH
    K26R
    NV1G2133 K28H 566 GPYCQKWMWTCDSERKCCEGMVCRLWCKK
    HLW-COOH
    NV1G2070 S11T 567 GPYCQKWMWTCDTERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2317 K28D 568 GPYCQKWMWTCDSERKCCEGMVCRLWCKK
    DLW-COOH
    NV1G2116 K27T 569 GPYCQKWMWTCDSERKCCEGMVCRLWCKTK
    LW-COOH
    NV1G2174 R22Q 570 GPYCQKWMWTCDSERKCCEGMVCQLWCKK
    KLW-COOH
    NV1G2209 K14N 571 GPYCQKWMWTCDSERNCCEGMVCRLWCKK
    KLW-COOH
    NV1G2134 W7H 572 GPYCQKWMHTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2166 K4P 573 GPYCQPWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2119 Q3G 574 GPYCGKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2285 D10Q 575 GPYCQKWMWTCQSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2067 Y1S, K4E, 576 GPSCQEFLWTCDAERKCCEGLVCRLWCKKKLW-
    W5F, M6L, COOH
    S11A, M19L
    NV1G2299 K27L 577 GPYCQKWMWTCDSERKCCEGMVCRLWCKLK
    LW-COOH
    NV1G2316 V20Y 578 GPYCQKWMWTCDSERKCCEGMYCRLWCKKK
    LW-COOH
    NV1G2322 L29N 579 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    NW-COOH
    NV1G2156 W7Y 414 GPYCQKWMYTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2082 W7E 415 GPYCQKWMETCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G2165 D10A 580 GPYCQKWMWTCASERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2201 V20L 581 GPYCQKWMWTCDSERKCCEGMLCRLWCKKK
    LW-COOH
    NV1G2077 Q3F 582 GPYCFKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2173 V20A 583 GPYCQKWMWTCDSERKCCEGMACRLWCKKK
    LW-COOH
    NV1G2207 S11Y 584 GPYCQKWMWTCDYERKCCEGMVCRLWCKKK
    LW-COOH
    64087946 (−GP) 417 YCQKWMQTCDAERKCCEGFSC-(N-Me-Arg)-
    W7Q, S11A, LWCKKKLL-COOH
    Ml9F, V20S,
    R22Me,
    W30L
    64053366 (−GP) W7Q 418 YCQKWMQTCDDERKCCEGMVCRLWCKKKLL-
    S11D W30L COOH
    64087868 W7Q L29V 585 GPYCQKWMQTCDSERKCCEGMVCRLWCKKK
    VW-COOH
    NV1G2266 R13L 586 GPYCQKWMWTCDSELKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2287 D10R, E12R, 587 GPYCQKWMWTCRSREKCCEGMVCRLWCKKK
    R13E LW-COOH
    NV1G2041 K4E/E17R 588 GPYCQEWMWTCDSERKCCRGMVCRLWCKKK
    LW-COOH
    64053340 (−GP) W7Q 419 YCQKWMQTCDSERFCCEGMVCRLWCKKKL
    K14F W30L COOH
    64053236 W7Q K14F 420 GPYCQKWMQTCDSERFCCEGMVCRLWCKKK
    W30L LL-COOH
    64087881 D10, E12, E17 589 GPQCQKWMQTC-(L-aspartyl-4-
    side aminobutane)-A-(glutamyl-4
    chains and aminobutane)-RKCC-(glutamyl-4-
    C-terminus aminobutane)-GFVCRLWCKKKLW-
    derviatized (putrescine)
    with
    putrescine
    NV1G2217 T8I 590 GPYCQKWMWICDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2183 K4D, E17R 591 GPYCQDWMWTCDSERKCCRGMVCRLWCKK
    KLW-COOH
    64087894 (−GP) 592 YCQKWMQTCDIERKCCEGFVCRLWCKKKLW-
    W7Q, S11, COOH
    M19F
    64053223 W7Q S11I 421 GPYCQKWMQTCDIERKCCEGMVCRLWCKKKL
    W30L L-COOH
    NV1G2216 K28T 593 GPYCQKWMWTCDSERKCCEGMVCRLWCKKT
    LW-COOH
    NV1G2210 D10G 594 GPYCQKWMWTCGSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2314 G18H 595 GPYCQKWMWTCDSERKCCEHMVCRLWCKKK
    LW-COOH
    64032501 (−GP) W7Q 596 YCQKWMQTCDIERKCCEGMVCRLWCKKKLW-
    S11I COOH
    63955918 W7Q W30L 422 GPYCQKWMQTCDSERKCCEGMVCRLWCKKK
    LL-COOH
    NV1G2088 S11F 597 GPYCQKWMWTCDFERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2289 K27F 598 GPYCQKWMWTCDSERKCCEGMVCRLWCKFK
    LW-COOH
    64053210 W7Q E17N 423 GPYCQKWMQTCDSERKCCNGMVCRLWCKKK
    W30L LL-COOH
    64053210 W7Q E17N 423 GPYCQKWMQTCDSERKCCNGMVCRLWCKKK
    W30L LL-COOH
    64087907 (−GP) W7Q 424 YCQKWMQTCDSERKCCEGMVCRLWCKKKLW-
    COOH
    64032488 (−GP) W7Q 425 YCQKWMQTCDSERKCCEGMVCRLAWCKKKLL-
    W30L COOH
    63955931 Y1Q, W7Q, 599 GPQCQKWMQTCDAERKCCEGFVC-(N-
    S11A, M19F, omega-methyl-L-arginine)-LWCKKKLW-
    R22N- COOH
    omega-
    methyl-L-
    arginine
    64053301 W7Q S11V 426 GPYCQKWMQTCDVERKCCEGMVCRLWCKKK
    W30L LLCOOH
    NV1G2243 L29F 600 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    FW-COOH
    NV1G2227 Q3S 601 GPYCSKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    64053275 W7Q E17L 427 GPYCQKWMQTCDSERKCCLGMVCRLWCKKK
    W30L LL-COOH
    64053275 W7Q E17L 427 GPYCQKWMQTCDSERKCCLGMVCRLWCKKK
    W30L LL-COOH
    64087920 Y1Q, W7Q, 602 GPQCQKWMQTCDAERKCCEG-(4-chloro-
    S11A, M19 Phe)-VCRLWCKKKLW-COOH
    (4-Cl-Phe)
    64053327 (−GP) W7Q 428 YCQKWMQTCDSERKCCNGMVCRLWCKKKLL-
    E17N COOH
    W30L
    NV1G2233 E12Q 603 GPYCQKWMWTCDSQRKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2265 Q3Y 604 GPYCYKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2172 K27V 605 GPYCQKWMWTCDSERKCCEGMVCRLWCKVK
    LW-COOH
    NV1G2248 E17V 606 GPYCQKWMWTCDSERKCCVGMVCRLWCKK
    KLW-COOH
    NV1G2039 S11I 607 GPYCQKWMWTCDIERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G2229 G18R 608 GRYCQKWMWTCDSERKCCERMVCRLWCKKK
    LW-COOH
    NV1G2099 L29V 609 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    VW-COOH
    NV1G2324 E17Y 429 GPYCQKWMWTCDSERKCCYGMVCRLWCKKK
    LW-COOH
    NV1G2096 K27I 610 GPYCQKWMWTCDSERKCCEGMVCRLWCKIK
    LW-COOH
    NV1G2094 E17I 430 GPYCQKWMWTCDSERKCCIGMVCRLWCKKK
    LW-COOH
    NV1G1996 E17L 431 GPYCQKWMWTCDSERKCCLGMVCRLWCKKK
    LW-COOH
    NV1G2039 (−GP) S11I 611 YCQKWMWTCDIERKCCEGMVCRLWCKKKLW-
    (−GP) COOH
    63930854 Y1Q, W7Q, 612 GPQCQKWMQTCDIERKCCLGFVCRLWCKKKL
    S11I, E17L, W-COOH
    M19F
    63909404 Y1Q, W7Q, 613 GPQCQKWMQTCDIERKCCEGFVCRLWCKKKV
    S11I, M19F, W-COOH
    L29V
    63930880 Y1Q, W7Q, 614 GPQCQKWMQTCDAERKCCLGFVCRLWCKKK
    S11A, E17L, VW-COOH
    M19F, L29V
    63909378 Y1Q, W7Q, 615 GPQCQKWMQTCDAERKCCEGFVCRLWCKKK
    S11A, M19F, VW-COOH
    L29V
    63930841 W7Q 416 GPYCQKWMQTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G714 Y1Q 616 GPQCQKWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G690 Y1S 617 GPSCQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G688 Y1R 618 GPRCQKWMWTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G700 S11A 619 GPYCQKWMWTCDAERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G692 Y1A 620 GPACQKWMWTCDSERKCCEGMVCRLWCKK
    KLW-COOH
    NV1G1051 T8S 621 GPYCQKWMWSCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G702 S11R 622 GPYCQKWMWTCDRERKCCEGMVCRLWCKK
    KLW-COOH
    NV1D1328_1 M6F 623 GPYCQKWFWTCDSERKCCEGMVCRLWCKKKL
    W-COOH
    NV1G694 W7Q 624 GPYCQKWMQTCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1D1339_1 L23T 625 GPYCQKWMWTCDSERKCCEGMVCRTWCKKK
    LW-COOH
    NV1G698 D10S 626 GPYCQKWMWTCSSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1055 W30S 627 GPYCQKWMWTCDSERKCCEGMVCRLWCKKK
    LS-COOH
    NV1G1635 K14A 628 GPYCQKWMWTCDSERACCEGMVCRLWCKKK
    LW-COOH
    NV1G224 M19S 629 GPYCQKWMWTCDSERKCCEGSVCRLWCKKKL
    W-COOH
    NV16704 V20S 630 GPYCQKWMWTCDSERKCCEGMSCRLWCKKK
    LW-COOH
    NV1D1335_1 K14D 631 GPYCQKWMWTCDSERDCCEGMVCRLWCKK
    KLW-COOH
    NV1G1057 K27R 632 GPYCQKWMWTCDSERKCCEGMVCRLWCKRK
    LW-COOH
    NV1G217 E12S 633 GPYCQKWMWTCDSSRKCCEGMVCRLWCKKK
    LW-COOH
    NV1G225 R22K 634 GPYCQKWMWTCDSERKCCEGMVCKLWCKKK
    LW-COO H
    NV1G696 T8R 635 GPYCQKWMWRCDSERKCCEGMVCRLWCKKK
    LW-COOH
    NV1D1331_1 S11P 636 GPYCQKWMWTCDPERKCCEGMVCRLWCKKK
    LW-COOH
    NV1G1047 K28R 637 GPYCQKWMWTCDSERKCCEGMVCRLWCKKR
    LW-COOH
    NV1G576 M19Y 638 GPYCQKWMWTCDSERKCCEGYVCRLWCKKKL
    W-COOH
    NV1G581 M19F 639 GPYCQKWMWTCDSERKCCEGFVCRLWCKKKL
    W-COOH
    NVID1388_1 L23R 640 GPYCQKWMWTCDSERKCCEGMVCRRWCKK
    KLW-COOH
    NV1D1333_1 R13N 641 GPYCQKWMWTCDSENKCCEGMVCRLWCKK
    KLW-COOH
    NV1G2349 Protoxin-II 642 GPYCQKWMWTCDSERKCCEGMVCRKWCKK
    L23K (+GP) KLW-COOH
    NV1G585 Protoxin-II 643 GPYCQKWMWTCDSERKCCEGRVCRLWCKKK
    M19R LW-COOH
    (+GP)
    64151490 Protoxin-II 644 GPYCQKWMQTCDSERKCCEGMVC-N-
    W7Q W30L omega,N-omega-dimethyl(asymmetric)-L-
    R22Me(2) arginine)-LWCKKKLL-COOH
    (+GP)
    NV1G587 Protoxin-II 645 GPYCQKWMWTCDSERKCCEGNVCRLWCKKK
    M19N LW-COOH
    (+GP)
    NV1G2352 Protoxin-II 646 GPYCQQWMWTCDSERKCCEGMVCRLWCKK
    K4Q (+GP) KLW-COOH
    NV1G2035 Protoxin-II 647 GPYCQKWMWTCDSERKCCENMVCRLWCKKK
    G18N LW-COOH
    (+GP)
    NV1G2351 Protoxin-II 648 GPYCQKWMWTCDSERKCCGGMVCRLWCKK
    E17G (+GP) KLW-COOH
    NV1G2346 Protoxin-II 649 GPYCQKWMWTCDGERKCCEGMVCRLWCKK
    S11G (+GP) KLW-COOH
    NV1G2341 Protoxin-II 650 GPYCQKWMWTCDSERKCCEGMFCRLWCKKK
    V20F (+GP) LW-COOH
    NV1G2342 Protoxin-II 651 GPYCQKWMWTCTSERKCCEGMVCRLWCKKK
    D10T (+GP) LW-COOH
    NV1G2348 Protoxin-II 652 GPYCQKWMWTCDSERKCCEGMVCRLWCKK
    K28Q (+GP) QLW-COOH
    NV1G1934 Protoxin-II 653 GPYCQKWMWTCDEERKCCEGMVCRLWCKKK
    S11E (+GP) LW-COOH
    NV1G2347 Protoxin-II 654 GPYCQHWMWTCDSERKCCEGMVCRLWCKK
    K4H (+GP) KLW-COOH
    NV1G584 Protoxin-II 655 GPYCQKWMWTCDSERKCCEGHVCRLWCKKK
    M419H LW-COOH
    (+GP)
    NV1G2033 Protoxin-II 656 GPYCQKWMWTCDSERKCCEGMVCRIWCKKK
    L23I (+GP) LW-COOH
    NV1G2343 Protoxin-II 657 GPYCRKWMWTCDSERKCCEGMVCRLWCKKK
    Q3R (+GP) LW-COOH
    NV1G2344 Protoxin-II 658 GPHCQKWMWTCDSERKCCEGMVCRLWCKK
    Y1H (+GP) KLW-COOH
    NV1G2345 Protoxin-II 659 GPGCQKWMWTCDSERKCCEGMVCRLWCKK
    Y1G (+GP) KLW-COOH
    NV1G2034 Protoxin-II 660 GPYCQKWMWTCDSERKCCEGMVCRLGCKKK
    W24G LW-COOH
    (+GP)
    NV1G594 Protoxin-II 661 GPYCQKWKWTCDSERKCCEGMVCRLWCKKK
    M6K (+GP) LW-COOH
    NV1G1041 Protoxin-II 662 GPYCQKWMWTCDQERKCCEGMVCRLWCKK
    S11Q (+GP) KLW-COOH
  • Select variants were characterized for their inhibition of Nav1.7 using veratridine-induced depolarization inhibition assay or Qpatch as described in Example 3. Table 19 shows the IC50 values obtained. For some variants, only % inhibition (% blk; percent block of control) at single concentration (10 nM or 30 nM) was recorded for Qpatch. se; standard error.
  • TABLE 19
    hNav1.7
    Veratridine-induced
    Depolarization
    SEQ Inhibition Assay QP
    ID IC50 IC50
    Peptide ID NO: (nM) ± (nM) se % blk se
    NV1G2228 434 4.69 2.70E−01 59.8% @ 10 nM 7.2
    NV1G2072 435 4.71 0.291 82.2% @ 10 nM 2.5
    NV1G2008 436 5.6 0.6 57.1% @ 10 nM 4.6
    NV1G1994 437 6.5 0.3 4.138 69.1% @ 10 nM 7.8
    NV1G2070 438 6.46 0.438 2.8889 74.5% @ 10 nM 4.6
    NV1G2074 439 6.48 0.482 71.3% @ 10 nM 3.3
    NV1G2079 440 6.65 0.608 69.4% @ 10 nM 3.2
    NV1G2073 441 6.73 0.572 4.6 71.2% @ 10 nM 3.9
    NV1G2076 442 6.93 0.764 2.77 76.1% @ 10 nM 2.2
    NV1G1864 443 22.3 0.141 52.3% @ 10 nM 7.8
    S11I
    NV1G2039 444 7.15 0.579 2.586 71.8% @ 10 nM 0.8
    NV1G1007 445 13.3 1.17 1.4 65.8% @ 10 nM 2.9
    W30tryptophanol
    NV1G2238 446 7.47 5.84E−01 32.1% @ 10 nM 9.8
    NV1G2198 447 7.49 0.856 37.6% @ 10 nM 7.6
    Nv102195 448 7.66 0.48 62.4% @ 10 nM 2.4
    NV1G1153-N- 449 7.1 0.9 1.2 1.3 56.1% @ 30 nM 7.9
    methyl
    NV1G2007 450 8.4 1.1 46.5% @ 10 nM 2.4
    NV1G2140 451 8.55 1.46
    NV1G2003 452 8.8 1.5 51.8% @ 10 nM 5.1
    NV1G2236 453 9.12 7.75E−01 45.3% @ 10 nM 4.3
    NV1G2164 454 9.37 0.507
    NV1G1864 455 9.38 5.32E−01 28.4% @ 10 nM 18.2
    E17L
    (-GP) 109 9.47 1.28 2.6 1.4 50.9% @ 10 nM 4.7
    NV1G1001
    NV1G2149 456 9.61 0.834 62.3% @ 10 nM 4.6
    NV1G2226 457 9.71 7.19E−01 24.2% @ 10 nM 6.0
    NV1G2286 458 9.85 0.923
    NV1G2128 459 9.94 0.945 63.8% @ 10 nM 4.9
    NV1G2041 460 9.98 1.07 4.791 53.4% @ 10 nM 4.4
    NV1G2001 461 10.9 0.6 39.9% @ 10 nM 5.6
    NV1G2019 462 11 0.787 44.2% @ 10 nM 4.0
    NV1G2002 463 11.0 0.9 36.9% @ 10 nM 5.8
    NV1G2225 464 11.2 7.85E−01 37.6% @ 10 nM 8.1
    NV1G2012 465 11.3 0.7 35.8% @ 10 nM 7.5
    NV1G2020 466 12 47.5 40.7% @ 10 nM 17.9
    NV1G2334 467 12 5.52E−01
    NV1G2025 468 12.3 0.853 7.4 73.9% @ 10 nM 7.2
    NV1G2131 469 12.4 1.58 61.8% @ 10 nM 2.8
    NV1G1007 470 12.5 1.3 28.1% @ 10 nM 18.0
    A11I, E12T
    NV1G2268 471 12.5 0.861 1.8 61.8% @ 10 nM 2.7
    NV1G2332 472 123 7.44E−01
    NV1G2010 473 12.5 1.0 56.4% @ 30 nM 3.8
    NV1G2053 474 12.5 33.3 73.1% @ 10 nM 2.40
    NV1G1519 133 12.9 0.943 52.3% @ 10 nM 7.9
    NV1G2253 475 13.5 0.695
    NV1G2055 476 14.6 8.58 73.5% @ 10 nM 5.50
    NV1G2338 477 14.8 6.98E−01 2.4 62.2% @ 10 nM 4.7
    NV1G2030 478 15.2 1.3 9.291 68.4% @ 30 nM 4.3
    NV1G2024 479 153 1.76 78.1% @ 30 nM 3.2
    NV1G2004 480 15.6 1.4 44.1% @ 30 nM 5.9
    NV1G2336 481 15.8 1.14E+00
    NV1G2011 482 16.0 1.5 56.7% @ 30 nM 8.8
    NV1G2080 483 16.1 1.81 13.43 70.2% @ 30 nM 4.6
    NV1G2288 484 16.3 1.52
    NV1G2142 485 16.4 0.834 5.3 51.2% @ 10 nM 2.9
    NV1G2232 408 16.7 1.32 5.0 56.5% @ 10 nM 5.7
    NV1G2193 486 16.8 1.23 43.3% @ 10 nM 11.3
    NV1G2230 487 17 2.42 9.5 41.3% @ 10 nM 4.5
    NV1G2182 409 17.3 1.37 3.8 54.2% @ 10 nM 5.4
    NV1G1153 C- 488 29.1 0.125 5.3 66.0% @ 10 nM 5
    terminal
    palmitoyl-
    lysine
    NV1G2339 489 18.1 1.35E+00
    NV1G2016 490 18.3 1.5 71.1% @ 30 nM 5.6
    NV1G2017 491 18.4 1.47 38.9% @ 30 nM 11.8
    NV1G2111 492 18.5 2.06 1.4 57.3% @ 10 nM 5.6
    NV1G2330 493 183 2.04E+00
    NV1G2204 494 18.8 0.578 49.0% @ 10 nM 13.0
    NV1G2026 495 18.9 1.48 80.2% @ 30 nM 2.2
    NV1G1007 496 18.9 1.2 3.9 56.5% @ 10 nM 6.8
    with C-terminal 5x
    Gly
    NV1G2038 497 18.9 1.46 64.8% @ 30 nM 3.3
    NV1G2305 498 20.4 5.08 6.2 41.5% @ 10 nM 4.5
    NV1G2021 499 20.4 1.88 39.76 60.5% @ 30 nM 6.9
    NV1G2319 410 20.7 2.3 9.7 43.2% @ 10 nM 6.2
    NV1G2100 500 20.8 1.65 35.2% @ 10 nM 10.8
    NV1G2130 501 21.2 2.48 20.9% @ 10 nM 5.7
    NV1G2081 502 21.9 1.99 29.5% @ 30 nM 10.5
    NV1G2252 503 22.2 1.54 2.9 63.1% @ 10 nM 6.5
    NV1G2040 504 22.7 2.17 55.5% @ 30 nM 9.1
    NV1G2146 505 22.86 2.3 20.62 53.1% @ 10 nM 19.9
    NV1G1153-N- 506 24 3.14 4.7 4.2 36.7% @ 10 nM 16.7
    ethyl
    NV1G2098 507 24.1 5.44 48.4% @ 10 nM 8.4
    NV1G2191 508 24.1 1.79  3.7% @ 10 nM 7.8
    NV1G2333 509 24.3 2.00E+00
    NV1G2224 510 24.3 1.59 10.4 34.5% @ 10 nM 7.7
    NV1G1001-N- 511 25.1 2.21 4.77 74.3% @ 30 nM 1.0
    ethyl
    NV1G1996 431 25.2 2.1 6.4 3.5 54.5% @ 30 nM 8.4
    NV1G2337 512 25.6 1.10E+00 8.5 48.0% @ 10 nM 7.5
    NV1G2301 513 25.7 3.83
    NV1G2075 514 26.1 1.8 36.8% @ 10 nM 10.7
    NV1G2278 515 26.3 3.34 1.5 58.7% @ 10 nM 5.45
    NV1G2014 516 27 3.43 36.4% @ 30 nM 7.6
    NV1G2065 517 27 2.53   53% @ 10 nM 2.6
    NV1G2099 518 27.9 2.54 3.4 41.7% @ 10 nM 10.1
    NV1G1007 519 28.4 2 5.6 31.9% @ 10 nM 16.5
    E17L
    NV1G1007 520 29.1 2.11
    G33
    1007A11I 521 29.3 2.8 9.6 38.5% @ 10 nM 5.4
    NV1G2221 522 29.3 1.89 31.3% @ 10 nM 7.5
    NV1G2097 523 29.9 2.92  7.0% @ 10 nM 12.2
    NV1G2029 524 30.1 6.29 50.8% @ 30 nM 0.4
    NV1G2257 525 30.1 1.7 4.9 50.9% @ 10 nM 8.4
    NV1G1998 526 30.6 2.7  6.0% @ 30 nM 5.0
    NV1G2068 527 30.7 3.11 24.0% @ 30 nM 20.0
    NV1G1001 65 30.8 2.34 20.3% @ 10 nM 8.6
    NV1G2137 528 30.9 6.08
    NV1G2199 529 31.7 1.72 29.6% @ 10 nM 4.5
    NV1G2300 530 32.6 3.69
    NV1G2124 531 32.7 8.78 33.8% @ 10 nM 9.1
    NV1G2254 532 32.8 3.85 34.1% @ 10 nM 10.3
    NV1G2239 533 33.8 2.39 14.6 42.2% @ 10 nM 10.1
    NV1G2255 534 34.2 2.55
    NV1G2256 535 34.4 1.98 17.3 27.7% @ 10 nM 13.4
    NV1G2095 536 35 6.48 18.8% @ 10 nM 7.2
    NV1G2220 537 36.7 3.86  8.4% @ 10 nM 5.7
    NV1G2154 538 37.7 2.44 12.5% @ 10 nM N/A
    NV1G2329 411 38 2.43E+00
    NV1G2122 539 38.4 5.7 22.4% @ 10 nM 10.5
    NV1G1007 C- 540 39.7 3.22
    terminal
    palmitoyi-
    lysine
    NV1G2000 541 40.0 6.3
    NV1G2009 542 40.8 3.2
    NV1G2066 543 41.7 4.56
    NV1G2083 544 43 3.71
    NV1G2126 545 43.9 11.6  0.4% @ 10 nM 9.4
    NV1G2043 370 46.4 4.09 58.7 36.5
    NV1G2050 546 46.7 6.26 49.1% @ 30 nM 11.50
    NV1G2071 547 47 5.73
    NV1G2129 412 47.3 3.81 −6.5% @ 10 nM 6.5
    NV1G2086 548 47.3 5.5
    NV1G2057 341 50.6 6.33 22.2% @ 30 nM 12.20
    NV1G2093 549 50.8 5.42
    NV1G1995 550 51.3 3.6
    NV1G2312 551 51.5 5.05
    NV1G2176 552 52.9 3.3
    NV1G2046 553 53.1 6.52 11.2% @ 30 nM 11.5
    NV1G2047 554 53.7 4.23 40.3% @ 30 nM 12.5
    NV1G2170 555 55.4 3.41
    NV1G2042 556 56.5 3.71
    NV1G2117 557 56.9 8.86 42.7% @ 30 nM 13.0
    NV1G1999 558 57.1 18.2
    NV1G2247 559 57.7 8.37 9.9 34.2% @ 10 nM 6.4
    NV1G2054 560 57.8 7.98 33.0% @ 30 nM 13.40
    NV1G1007 561 59.5 4.12  6.1% @ 10 nM 13.4
    E17F
    NV1G2056 562 59.6 4.36 26.3% @ 30 nM 16.10
    NV1G1007 563 63 5.52  7.4% @ 10 nM 10.2
    D33
    NV1G2291 413 63.3 14.9
    NV1G2306 564 64.4 4.75
    NV1G2023 565 66.2 9.12
    NV1G2133 566 68.9 11.7 28.6% @ 10 nM 6.2
    NV1G2317 568 71.2 5.72
    NV1G2116 569 71.5 7.97 10.4% @ 30 nM 20.9
    NV132174 570 72.7 6.86
    NV1G2209 571 77.8 6.33 13.7 39.96% @ 10 nM  7.6
    NV1G2134 572 78.3 7.06  9.9% @ 10 nM 3.5
    NV1G2166 573 80.4 5.72
    NV1G2119 574 82.1 21.5
    NV1G2285 575 82.9 6.47
    NV1G2067 576 85.2 13
    NV1G2299 577 88.1 21.3
    NV1G2316 578 88.5 7.99
    NV1G2322 579 90 6.48 35.2% @ 10 nM 4.1
    NV1G2156 414 90.5 6.88
    NV1G2082 415 90.8 11.4
    NV1G2165 580 91.6 6.58
    NV1G2201 581 94.8 5.67 13.957% @ 10 nM   4.5
    NV1G2077 582 95.4 11.9
    NV1G2173 583 99.9 10.6
    NV1G2207 584 20.5% @ 10 nM 4.8
    64087946 417 23.8 20.7% @ 10 nM 10.9
    64053366 418 22.1% @ 10 nM 3.5
    64087868 585 64.9 22.9% @ 10 nM 4.2
    NV1G2266 586 23.5% @ 10 nM 6.2
    NV1G2287 587 24.8% @ 10 nM 8.3
    64053340 419 26.8% @ 10 nM 3.7
    64053236 420 28.0% @ 10 nM 13.2
    64087881 589 28.4% @ 10 nM 5.4
    NV1G2217 590 29.4% @ 10 nM 9.3
    NV1G2183 591 31.0% @ 10 nM 7.7
    64087894 592 9.4 31.0% @ 10 nM 3.8
    64053223 421 33.0% @ 10 nM 5.8
    NV1G2216 593 33.5% @ 10 nM 7.0
    NV1G2210 594 34.3% @ 10 nM 5.5
    NV1G2314 595 34.9% @ 10 nM 7.5
    64032501 596 9.3 35.1% @ 10 nM 6.3
    63955918 422 10.8 38.50% @ 10 nM  4.5
    NV1G2088 597 41.4 % @ 30 nM 4.0
    NV132289 598 14.3 41.4% @ 10 nM 5.9
    64053210 423 41.7% @ 10 nM 6.2
    64053210 423 41.7% @ 10 nM 6.2
    64087907 424 7.1 45.1% @ 10 nM 6.0
    64032488 425 6.5 45.6% @ 10 nM 4.6
    63955931 599 6.2 45.66% @ 10 nM  4.6
    64053301 426 10.7 45.83% @ 10 nM  3.3
    NV1G2243 600 47.6% @ 10 nM 4.8
    NV1G2227 601 8.1 47.7% @ 10 nM 6.3
    64053275 427 2.9 48.22% @ 10 nM  5.2
    64053275 427 2.9 48.22% @ 10 nM  5.2
    64087920 602 2.6 50.3% @ 10 nM 8.9
    64053327 428 7.9 51.9% @ 10 nM 2.6
    NV1G2233 603 52.8% @ 10 nM 2.0
    NV1G2265 604 53.1% @ 10 nM 7.0
    NV1 32172 605 54.4% @ 30 nM 6.7
    NV1G2248 606 5.2 54.8% @ 10 nM 3.6
    NV1G2229 608 55.9% @ 10 nM 7.0
    NV1G2324 429 57.5% @ 10 nM 3.9
    NV1G2096 610 61.5% @ 30 nM 22.8
    NV1G2094 430 63.2% @ 30 nM 6.2
    NV1G2039 611 1.9 78.9% @ 10 nM 2.5
    (-GP)
    63930854 612 5.1
    63909404 613 9.1
    63930880 614 12.2
    63909378 615 12.5
    63930841 416 20.9
    NV1G714 616 1.3 1.4
    NV1G690 617 1.9 1.2
    NV1G688 618 2.2 0.4
    NV1G700 619 2.5 1.3
    NV1G692 620 2.8 1.4
    NV1G1051 621 5.0 3.0 38.6% @ 10 nM 8.5
    NV1G702 622 5.5 4.0 62.8% @ 10 nM 5.8
    NV1D1328_1 623 6.4 1.5
    NV1G694 624 24.1 23.5
    NV1D1339_1 625 21.5% @ 10 nM 13.6
    NV1G698 626 22.8% @ 10 nM
    NV1G1055 627 22.9% @ 10 nM 3.6
    NV1G1635 628 24.3% @ 10 nM 10.0
    NV1G224 629 24.4% @ 20 nM
    NV1G704 630 24.8% @ 3 nM  2.7
    NV1G1335_1 631 25.0% @ 10 nM
    NV1G1057 632 26.7% @ 10 nM 5.4
    NV1G217 633 30.8% @ 10 nM 2.7
    NV1G225 634 30.8% @ 10 nM 5.9
    NV1G696 635 31.1% @ 10 nM
    NV1D1331_1 636 43.7% @ 10 nM
    NV1G1047 637 47.7% @ 10 nM 6.5
    NV1G576 638 60.1% @ 10 nM
    NV1G581 639 60.2% @ 10 nM 6.0
    NV1G2349 642 10.1% @ 10 nM 7.9
    NV1G585 643 16.2% @ 10 nM 13.1
    64151490 644 32.5 18.3% @ 10 nM 20.5
    NV1G587 645 20.6% @ 10 nM 12.8
    NV1G2352 646 23.4% @ 10 nM 9.2
    NV1G2035 647 27.7% @ 10 nM 6.7
    NV1G2351 648 28.9% @ 10 nM 9.3
    NV1G2346 649 33.6% @ 10 nM 12.4
    NV1G2341 650 35.8% @ 10 nM 2.2
    NV1G2342 651 39.2% @ 10 nM 13.0
    NV1G2348 652 41.7% @ 10 nM 10.8
    NV1G1934 653 53.0% @ 10 nM 6.1
    NV1G2347 654 56.3% @ 10 nM 14.8
    NV1G584 655 56.4% @ 10 nM 4.9
    NV1G2033 656 59.1% @ 10 nM 3.6
    NV1G2343 657 59.6% @ 10 nM 3.5
    NV1G2344 658   63% @ 10 nM 3.8
    NV1G2345 659 64.8% @ 10 nM 10.4
    NV1G2034 660  7.0% @ 10 nM 3.6
    NV1G594 661
    NV1G1041 662
    • EXAMPLE 9 Generation of Variants of 63955918
  • Protoxin-II variant 63955918 has W7Q and W30L substitutions when compared to the wild type Protoxin-II. As described in Example 6, mutation of both Trp7 and Trp30 alone or in combination improves folding of the resulting ProtoxinII variants, and could rescue folding of difficult-to-refold Protoxin-II variants.
  • Additional variants were generated onto the 63955918 backbone to evaluate possibility of further improving characteristics of the molecule. Some variants are also described in Examples 6 and 7.
  • The generated variants and their sequences are shown in Table 20.
  • TABLE 20
    SEQ
    ID Mutations ID NO: Sequence
    64053366 Protoxin-II 418 YCQKWMQTCDDERKCCEGMVCRLWCKKKLL-
    W7Q S11D COOH
    W30L (−GP)
    64053340 Protoxin-II 419 YCQKWMQTCDSERFCCEGMVCRLWCKKKLL-
    W7Q K14F COOH
    W30L (−GP)
    64053236 Protoxin-II 420 GPYCQKWMQTCDSERFCCEGMVCRLWCKKKLL-
    W7Q K14F COOH
    W30L (+GP)
    64053223 Protoxin-II 421 GPYCQKWNIQTCDIERKCCEGMVCRLWCKKKLL-
    W7Q S11I COOH
    W30L (+GP)
    64053210 Protoxin-II 423 GPYCQKWMQTCDSERKCCNGMVCRLWCKKKLL-
    W7Q E17N COOH
    W30L (+GP)
    64053301 Protoxin-II 426 GPYCQKWMQTCDVERKCCEGMVCRLWCKKKLL-
    W7Q S11V COOH
    W30L (+GP)
    64053275 Protoxin-II 427 GPYCQKWMQTCDSERKCCLGMVCRLWCKKKLL-
    W7Q E17L COOH
    W30L (+GP)
    64053327 Protoxin-II 428 YCQKWMQTCDSERKCCNGMVCRLWCKKKLL-
    W7Q E17N COOH
    W301 (−GP)
    64159108 nerve labeling 663 SHSNTQTLAKAPEHTGAPAPAPAPAPYCQKWMQTC
    peptide-5xAP- DSERKCCEGMVCRLWCKKKLL-COOH
    Protoxin-II
    W7Q W30L
    64151477 Protoxin-II 664 YCQKWMQTCDSYRFCCEGMVCRLWCKKKLL-NH-
    W7Q W30L methyl
    K14F E12Y N-
    methyl (−GP)
    64053288 Protoxin-II 665 GPYCQEWMQTCDSERKCCRGMVCRLWCKKKLL-COOH
    W7Q K4E E17R
    W30L (+GP)
    64106666 Protoxin-II 666 YCQKWMQTCDSERKCCKGMVC-(4-guanidino-L-
    W7Q E17L W30L phenytalanine)-LWCKKKLL-COOH
    R22F(Guanidino)
    (−GP)
    64159134 Protoxin-II 667 YCQKWMQTCDSERKCCEGMVC-(4-guanidino-L-
    W7Q W30L phenylalanine)-LWCKKKLL-COOH
    R22F(Guanidino)
    (−GP)
    64106575 Protoxin-II 668 YCQKWMQTCDVERKCCLGMVCRLWCKKKLL-
    W7Q E17L COOH
    W30L S11V 
    (−GP)
    64106627 Protoxin-II 669 YCQKWMQTCDSERKCCLPMVCRLWCKKKLL-COOH
    W7Q E17L
    W30L G18P 
    (−GP)
    64106640 Protoxin-II 670 YCQKWMQTCDSERKCCLGMVC-(N-omega-
    W7Q E17L methyl-L-arginine)-LWCKKKLL-COOH
    W30L R22Me 
    (−GP)
    64106653 Protoxin-II 671 YCQKWMQTCDSERKCCLGMVC-(N-omega,N-
    W7Q E17L ornega-dimethyl(asymmetric)-L-
    W30L arginine)-LWCKKKLL-COOH
    R22Me(2) (−GP)
    64159121 Protoxin-II WW 672 GPYCQKWMQTCDSERKCCEGMVC-(N-omega-
    R22Me (+GP) methyl-L-arginine)-LWCKKKLL-COOH
    64106757 Protoxin-II 673 YCYKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH
    W7Q W30L
    Q3Y (−GP)
    64106744 Protoxin-II 674 YCQKWMQTCDSERKCCEPMVCRLWCKKKLL-
    W7Q W30L COOH
    G18P (−GP)
    64106705 Protoxin-II 675 YCQKWMQTCDSERKCCLGMVCRLWCKKKLL-
    W7Q W30L COOH
    E17L (−GP)
    64106718 Protoxin-II 676 YCQKWMQTCDSERKCCQGMVCRLWCKKKLL-COOH
    W7Q W30L
    E17Q (−GP)
    64170171 Protoxin-II 677 YCQKWMQTCDSERKCC-(Glutamyl-4-
    W7Q W30L aminobutane)-GMVCRLWCKKKLL-COOH
    E17glutamyl-4-
    aminobutane(−GP)
    64106731 Protoxin-II 678 YCQKWMQTCDSYRKCCEGMVCRLWCKKKLL-
    W7Q W30L COOH
    E12Y (−GP)
    64159082 Protoxin-II 679 GPYCQKWMQTCDSERKCCEGMVCRLWCKKKLL-
    W7Q W30L OH
    Leucinol (+GP)
    64151503 Protoxin-II 680 HLNILSTLWKYRGPYCQKWMQTCDSERKCCEGMVC
    W7Q W30L RLWCKKKLL-COOH
    Tet1
    64151438 Protoxin-II 681 YCQKWMQTCDSERKCCEGMVCRLWCKKKLL-NH-
    W7Q W30L N- methyl
    methyl (−GP)
    64151464 Protoxin-II 682 YCQKWMQTCDSERFCCEGMVCRLWCKKKLL-NH
    W7Q W30L methyl
    K14F N-methyl
    (−GP)
    64170145 Protoxin-II 683 YCQKWMQTCDS-(Glutamyl-4-aminobutane)-
    W7Q W30L RKCCEGMVCRLWCKKKLL-COOH
    E12glutamyl-4-
    aminobutane
    (−GP)
    64170132 Protoxin-II 684 YCQKWMQTC-(Asparagyl-4-aminobutane)-
    W7Q W30L SERKCCEGMVCRLWCKKKLL-COOH
    D10asparagyl-
    4-aminobutane
    (−GP)
    64106601 Protoxin-II 685 YCQKWMQTCDSERFCCLGMVCRLWCKKKLL-
    W7Q E17L COOH
    W30L K14F (−GP)
  • The variants were characterized as described above. Table 21 shows the IC50 values and/or percent block (% blk) (% inhibition of currents in comparison to a control sample). Se: standard error.
  • TABLE 21
    Nav1.7
    Veratridine-induced
    Depolarization inhibition
    Protein SEQ Assay QP
    ID ID NO: 1C50 (nM) ± IC50 (nM) se % blk se
    64053366 418 22.1% @ 10 nM 3.5
    64053340 419 33.0 29.58% @ 10 nM  4.2
    64053236 420 28.0% @ 10 nM 13.2
    64053223 421 33.0% @ 10 nM 5.8
    64053210 423 41.7% @ 10 nM 6.2
    64053301 426 10.7 45.83% @ 10 nM  3.3
    64053275 427 4.9 48.69% @ 10 nM  4.1
    64053327 428 7.9 51.9% @ 10 nM 2.6
    64159108 663 53.5 13.3% @ 10 nM 9.7
    64151477 664 400.4 14.4% @ 30 nM 4.8
    64053288 665 17.8% @ 10 nM 4.1
    64106666 666 36.3 19.6% @ 10 nM 5.4
    64159134 667 131.7 21.3% @ 30 nM 3.2
    64106575 668 18.1 23.57% @ 10 nM  6.5
    64106627 669 32.4 26.3% @ 10 nM 3.0
    64106640 670 19.3 26.3% @ 10 nM 4.6
    64106653 671 20.4 26.4% @ 10 nM 6.6
    64159121 672 44.2 36.1% @ 30 nM 11.2
    64106757 673 14.4 37.0% @ 10 nM 2.2
    64106744 674 11.1 39.0% @ 10 nM 3.4
    64106705 675 8.8 41.6% @ 10 nM 4.3
    64106718 676 11.4 43.5% @ 10 nM 5.7
    64170171 677 6.2 56.7% @ 10 nM 6.9
    64106731 678 3.7 64.3% @ 10 nM 4.9
    64159082 679 3.6 65.5% @ 10 nM 8.0
    64151503 680 3.6 65.5% @ 10 nM 8.0
    64151438 681 2.5 66.2% @ 10 nM 7.1
    64151464 682 5.6 67.3% @ 10 nM 8.8
    64170145 683 2.2 75.0% @ 10 nM 4.4
    64170132 684 1.2 78.4% @ 10 nM 3.7
    64106601 685
    • EXAMPLE 10 Generation of Variants of 63955918
  • Additional variants of 63955918 were designed in order to improve biodistribution of the resulting peptides.
  • W7 and W30 substitutions were also designed on a variety of family 3 inhibitory cysteine knot peptides to assess whether the improved selectivity and improved refolding properties conferred by those mutations extended beyond Protoxin-II to other highly homologous peptide sequences. Family 3 spider toxins that inhibit Nav channels (NaSpTx) as defined by Klint et. al. (Toxicon 60:478-491, 2012), were chosen as scaffolds for incorporation of Q at position 7 and L at position 30 (numbering based on Seq ID NO: 1). These sequences include beta-theraphotoxin-Gr1c, beta-theraphotoxin-Gr1e, beta/kappa-theraphotoxin-Cg2a, kappa-theraphotoxin-Psla, kappa-theraphotoxin-Pslb, kappa-theraphotoxin-Gr2b, kappa-theraphotoxin-Gr2c, kappa-theraphotoxin-Gr2d, kappa-theraphotoxin-Cg2a, kappatheraphotoxin-Cg2b, kappa-theraphotoxin-Ec2c, beta-theraphotoxin-Gr1d, beta/kappa-theraphotoxin-Pm2a, kappa-theraphotoxin-Ec2a and kappa-theraphotoxin-Ec2b.
  • Additional family 3 NaSpTx scaffolds for mutation were identified in Arachnoserver (http://www_arachnoserver_org/_mainMenu html). Alignment of the family 3 toxins is shown in FIG. 14.
  • Table 22 shows the sequences of the designed variants.
  • TABLE 22
    SEQ
    ID
    Protein ID Mutations NO: Protein sequence
    (L-Lys(N-epsilon- N-terminal 686 (L-Lys(N-epsilon-
    (N-alpha- addition of (L- (N-alpha-
    Palmitoyl-L- Lys(N-epsilon-(N- Palmitoyl-L-
    gamma-glutamyl))- alpha-Palmitoyl- gamma-glutamyl))-
    PEG(2)-Protoxin- L-gamma- PEG(2)-
    II-W7Q W30L glutamyl))- YCQKWMQTCDSERKCCE
    PEG(2)on GMVCRLWCKKKLL-COOH
    Protoxin-II W7Q
    W30L
    (L-Lys(N-epsilon- N-terminal 687 (L-Lys(N-epsilon-
    (N-alpha- addition of (L- (N-alpha-
    Palmitoyl-L- Lys(N-epsilon-(N- Palmitoyl-L-
    gamma-glutamyl))- alpha-Palmitoyl- gamma-glutamyl))-
    GGGGS-Protoxin-II L-gamma- GGGGS-
    W7Q W30L glutamyl))GGGGS YCQKWMQTCDERRKCCE
    on Protoxin-II GMVCRLWCKKKLL-COOH
    W7Q W30L
    (L-Lys(N-epsilon- N-terminal 688 (L-Lys(N-epsilon-
    (N-alpha- addition(L- (N-alpha-
    Palmitoyl-L- Lys(N-epsilon-(N- Palmitoyl-L-
    gamma-glutamyl))- alpha-Palmitoyl- gamma-glutamyl))-
    PEG(2)-Protoxin- L-gamma- PEG(2)-
    II-W7Q W30L K14F glutamyl))- YCQKWMQTCDSERFCCE
    PEG(2)on GMVCRLWCKKKLL-COOH
    Protoxin-IIW7Q
    W30L K14F
    (L-Lys(N-epsilon- N-terminal 689 (L-Lys(N-epsilon-
    (N-alpha- addition of (L- (N-alpha-
    Palmitoyl-L- Lys(N-epsilon-(N- Palmitoyl-L-
    gamma-glutamyl))- alpha-Palmitoyl- gamma-glutamyl))-
    GGGGS-Protoxin-II L-gamma- GGGGS-
    W7Q W30L K14F glutamyl))-GGGGS- YCQKWMQTCDWSERFCCE
    on Protoxin-II GMVCRLWCKKKLL-COOH
    W7Q W30L K14F
    Protoxin-II W7Q Protoxin-II W7Q 690 YCQKWMQTC-
    W30L K14F W30L K14F (Asparagyl-4-
    D10aspararagyl-4- D10aspararagyl-4- aminobutane)-
    aminobutane (−GP) aminobutane (−GP) SERFCCEGMVCRLWCKK
    KLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 691 YCQKWMQTCDSERKCCE
    W30L G18P N  W30L G18P N-  PMVCRLWCKKKLL-N—Me
    methyl methyl
    Protoxin-II W7Q Protoxin-II W7Q 692 (4-bromo-L-
    W30L Y1 -- > 4- W30L Y1 -- > 4- phenylalanine)-
    bromo-Phe bromo-Phe CQKWMQTCDSERKCCEG
    MVCRLWCKKKLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 693 YCQK-(5-bromo-L-
    W30L W5 -- > 5- W30L W5 -- > 5- tryptophan)-
    bromo-Trp bromo-Trp CQKWMQTCDSERKCCEG
    MVCRLWCKKKLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 694 YCQKWMQTCDSERKCCE
    W30L W24 -- > 5- W30L W24 -- > 5- GMVCRL-(5-bromo-
    bromo-Trp bromo-Trp L-tryptophan)-
    CKKKLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 695 (4-chloro-L-
    W30L Y1 -- > 4- W30L Y1 -- > 4- phenylalanine)-
    chloro-Phe chloro-Phe CQKWMQTCDSERKCCEG
    MVCRLWCKKKLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 696 (3-chloro-L-
    W30L Y1 -- > 3- W30L Y1 -- > 3- tyrosine)-
    chloro-Tyr chloro-Tyr CQKWMQTCDSERKCCEG
    MVCRLWCKKKLL-COOH
    β/κ- β/κ- 697 YCQKWMQTCDSKRACCE
    theraphotoxin- theraphotoxin- GLECKLWCRKIWL-NH2
    Cg2a W7Q, R20E, Cg2a W7Q, R20E,
    I29W, addition of  I29W, addition of 
    L30 L30
    β-theraphotoxin β-theraphotoxin 698 YCQKWMQTCDSKRKCCE
    Gr1c W7Q G30L Gr1c W7Q G30L DMVCQLWCKKRLL-COOH
    β-theraphotoxin β-theraphotoxin 699 YCQKWMQTCDSERKCCE
    Gr1c W7Q G30L Gr1c W7Q G30L DMVCELWCKKRLL-COOH
    β/κ- β/κ- 700 YCQKWMQTCDSKRACCE
    theraphotoxin- theraphotoxin- GLRCKLWCRKIIL-COOH
    Cg2a W7Q  Cg2a W7Q 
    addition of L30 addition of L30
    κ-theraphotoxin- κ-theraphotoxin 701 YCQKWMQTCDSARKCCE
    Ps1a W7Q addition Ps1a W7Q addition GLVCRLWCKKIIL-COOH
    of L30 of L30
    κ-theraphotoxin- κ-theraphotoxin- 702 YCQKWMQTCDEERKCCE
    Ps1b W7Q N30L Ps1b W7Q N30L GLVCRLWCKRIILM-COOH
    κ-theraphotoxin- κ-theraphotoxin- 703 YCQKWMQTCDEERKCCE
    Gr2b W7Q E30L Gr2b W7Q E30L GLVCRLWCKKKILEG-COOH
    κ-theraphotoxin- κ-theraphotoxin- 704 YCQKWMQTCDEERKCCE
    Gr2c W7Q E30L Gr2c W7Q E30L GLVCRLWCKKKILW-COOH
    κ-theraphotoxin- κ-theraphotoxin- 705 YCQKWMQTCDEERKCCE
    Gr2d W7Q E30L Gr2d W7Q E30L GLVCRLWCKKKNLVVIS
    GEDTKLPTLKIQLMKSN
    ITDI-COOH
    κ-theraphotoxin- κ-theraphotoxin- 706 YCQKWMQTCDSERKCCE
    Cg2a W7Q addition Cg2a W7Q addition GYVCELWCKYNLL-COOH
    of L30 of L30
    κ-theraphotoxin- κ-theraphotoxin- 707 YCQKWMQTCDSERKCCE
    Cg2b W7Q G30L Cg2b W7Q G30L GYVCELWCKYNML-COOH
    (L-Lys(N-epsilon- Additon of N- 708 (L-Lys(N-epsilon-
    (N-alpha- terminal (L- (N-alpha-
    Palmitoyl-L- Lys(N-epsilon-(N- Palmitoyl-L-
    gamma-glutamyl))- alpha-Palmitoyl- gamma-glutamyl))-
    Protoxin-II W7Q L-gamma- YCQKWMQTCDSERKCCE
    W30L glutamyl)) on GMVCRLWCKKKLL-COOH
    Protoxin-II W7Q
    W30L
    Protoxin-II W7Q W7Q W30L S11 -- > 709 YCQKWMQTCD-(beta-
    W30L S11 -- > beta- beta-chloro-Ala chloro-L-alanine)-
    chloro-Ala ERKCCEGMVCRLWCKKK
    LL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 710 YCQKWMQTCDSERKCCE
    W30L-PEG(2)- W30L with GMVCRLWCKKKLL-
    (L-Lys(N-epsilon- addition of C- 2xPEG-(L-Lys(N-
    (N-alpha- terminal PEG(2)- epsilon-(N-alpha-
    Palmitoyl-L- (L-Lys(N-epsilon- Palmitoyl-L-
    gamma-glutamyl)) (N-alpha- gamma-glutamyl))-
    Palmitoyl-L- COOH
    gamma-glutamyl))
    Protoxin-II W7Q Protoxin-II W7Q 711 YCQKWMQTCDSERKCCE
    W30L-GGGGS-(L- W30L with C- GMVCRLWCKKKLL-
    (L-Lys(N-epsilon- terminal GGGGS- GGGGS-(L-Lys(N-
    (N-alpha- (L-Lys(N-epsilon- epsilon-
    Palmitoyl-L- (N-alpha- (N-alpha-
    gamma-glutamyl)) Palmitoyl-L- Palmitoyl-L-
    gamma-glutamyl)) gamma-glutamyl))-
    COOH
    Protoxin-II W7Q Protoxin-II W7Q 712 (4-bromo-L-
    W30L (Y1 -- > 4- W30L (Y1 -- > 4- phenylalanine)-
    bromo-Phe),  bromo-Phe),  CQKWMQTCD-(beta-
    (S11 -- > beta- (S11 -- > beta- chloro-L-
    chloro-Ala) chloro-Ala) alanine)-
    ERKCCEGMVCRLWCKKK
    LL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 713 (4-bromo-L-
    W30L (Y1 -- > 4- W30L (Y1 -- > 4- phenylalanine)-
    bromo-Phe), bromo-Phe), CQKWMQTCD-(beta-
    (S11 -- > beta- (S11 -- > beta- chloro-L-
    chloro-Ala), chloro-Ala), alanine)-
    (W24 -- > 5- (W24 -- > 5- ERKCCEGMVCRL-(5-
    bromo-Trp) bromo-Trp) bromo-L-
    tryptophan)-
    CKKKLL-COOH
    WW (S11 -- > beta- WW (S11 -- > beta- 714 CQKWMQTCD-(beta-
    chloro-Ala), chloro-Ala), chloro-L-
    (W24 -- > 5-bromo- (W24 -- > 5-bromo- alanine)-
    Trp) Trp) ERKCCEGMVCRL-(5-
    bromo-L-
    tryptophan)-
    CKKKLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 715 YCQKWMQTCD-
    W30L S11  W30L S11  (Lys(N-epsilon-
    (L-Lys(N-epsilon- (L-Lys(N-epsilon- (N-alpha-
    (N-alpha- (N-alpha- Palmitoyl-L-
    Palmitoyl-L- Palmitoyl-L- gamma-glutamyl))-
    gamma-glutamyl)) gamma-glutamyl)) ERKCCEGMVCRLWCKKK
    LL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 716 YCQKWMQTCDS-
    W30L E12  W30L E12  (L-Lys(N-
    (L-Lys(N-epsilon- (L-Lys(N-epsilon- epsilon-
    (N-alpha- (N-alpha- (N-alpha-
    Palmitoyl-L- Palmitoyl-L- Palmitoyl-L-
    gamma-glutamyl)) gamma-glutamyl)) gamma-glutamyl))
    RKCCEGMVCRLWCKKKLL-
    COOH
    WW E17  WW E17  717 YCQKWMQTCDSERKCC-
    (L-Lys(N-epsilon- (L-Lys(N-epsilon- (L-Lys(N-
    (N-alpha- (N-alpha- epsilon-
    Palmitoyl-L- Palmitoyl-L- (N-alpha-
    gamma-glutamyl)) gamma-glutamyl)) Palmitoyl-L-
    gamma-glutamyl))
    GMVCRLWCKKKLL-
    COOH
    Protoxin-II W7Q Protoxin-II W7Q 718 YCQKWMQTC-(L-
    W30L D10 L- W30L D10 L- asparagyl-4-
    asparagyl-4- asparagyl-4- aminobutane)-S-
    aminobutane E12 aminobutane E12 (L-glutamyl-4-
    L-glutamyl-4- L-glutamyl-4- aminobutane)-
    aminobutane E17 aminobutane E17 RKCC-(L-glutamyl-
    L-glutamyl-4- L-glutamyl-4- 4-aminobutane)-
    aminobutane aminobutane GMVCRLWCKKKLL-
    COOH
    Protoxin-II W7Q Protoxin-II W7Q 719 (4-bromo-L-
    W30L (Y1 -- > 4- W30L (Y1 -- > 4- phenylalanine)-
    bromo-Phe),(W5 -- > bromo-Phe),(W5 -- > CQK-(5-bromo-L-
    5-bromo-Trp) 5-bromo-Trp) tryptophan)-
    (W24 -- > 5-bromo- (W24 -- > 5-bromo- MQTCDSERKCCEGMVCR
    Trp) Trp) L-(5-bromo-L-
    tryptophan)-
    CKKKLL-COOH
    Protoxin-II W7Q Protoxin-II W7Q 720 (4-bromo-L-
    W30L (Y1 -- > 4- W30L (Y1 -- > 4- phenylalanine)-
    bromo-Phe), bromo-Phe), CQKWMQTCDSERKCCEG
    (W24 -- > 5- (W24 -- > 5- MVCRL-(5-
    bromo-Trp) bromo-Trp) bromotryptophan)-
    CKKKLL-COOH
    Protoxin-II  Protoxin-II  721 (3,4-dichloro-L-
    W7Q W30L W7Q W30L phenylalanine)-
    Y1 -- > 3,4 di- Y1 -- > 3,4 di- CQKWMQTCDSERKCCEG
    chloro-Phe chloro-Phe MVCRLWCKKKLL-COOH
    Protoxin-II  Protoxin-II 722 (3,5-dibromo-L-
    W7Q W30L W7Q W30L tyrosine)-
    Y1 -- > 3,5 di- Y1 -- > 3,5 di- CQKWMQTCDSWEKCCEG
    bromo-Tyr bromo-Tyr MVCRLWCKKKLL-COOH
    Protoxin-II Protoxin-II 723 (3,4,5-trifluoro-
    W7Q W30L W7Q W30L L-phenylalanine)-
    Y1 -- > 3,4,5  Y1 -- > 3,4,5 CQKWMQTCDSERKCCEG
    tri-fluoro-Phe tri-fluoro-Phe MVCRLWCKKKLL-COOH
    Protoxin-II Protoxin-II 724 (L-cyano-beta-
    W7Q W30L W7Q W30L alanine)-
    with additional N- with additional N- YCQKWMQTCDSERKCCE
    terminal L-cyano- terminal L-cyano- GMVCRLWCKKKLL-
    beta-alanine beta-alanine COOH
    Protoxin-II Protoxin-II 725 (propargylglycine)-
    W7Q W30L W7Q W30L YCQKWMQTCDSERKCCE
    with additional N- with additional N- GMVCRLWCKKKLL-
    terminal L- terminal L- COOH
    propargylglycine propargylglycine
    Protoxin-II Protoxin-II 726 (L-norvaline)-
    W7Q W30L W7Q W30L YCQKWMQTCDWERKCCE
    with additional N- with additional N- GMVCRLWCKKKLL-
    terminal L- terminal L- COOH
    norvaline norvaline
    κ-theraphotoxin- κ-theraphotoxin- 727 YCQFKMQTCDSERKCCE
    Ec2c W7Q addition Ec2c W7Q addition DMVCRLWCKLNLL-
    of L30 of L30 COOH
    β-theraphotoxin- β-theraphotoxin- 728 YCQKWLQTCDSERKCCE
    Gr1d W7Q G30L Gr1d W7Q G30L DMVCRLWCKKRLL-
    COOH
    β/κ- β/κ- 729 YCQEFLQTCDEERKCCG
    Theraphotoxin- Theraphotoxin- DMVCRLWCKKRLL-
    Pm2a W7Q addition Pm2a W7Q addition COOH
    of L30 of L30
    κ-theraphotoxin- κ-theraphotoxin- 730 YCQKFLQTCDTERKCCE
    Ec2a W7Q addition Ec2a W7Q addition DMVCELWCKLEKL-
    of L30 of L30 COOH
    κ-theraphotoxin- κ-theraphotoxin- 731 YCQKFLQTCDTERKCCE
    Ec2B W7Q addition Ec2B W7Q addition DMVCELWCKYKEL-
    of L30 of L30 COOH
    Protoxin-II W7Q W30L E12Y N- 732 YCQKWMQTCDSYRKCCE
    WQ W30L E12Y N- methyl GMVCRLWCKKKLL-N—Me
    methyl
    Protoxin-II W7Q W30L Q3Y N- 733 YCYKWMQTCDSERKCCE
    W7Q W30L Q3Y N- methyl GMVCRLWCKKKLL-N—Me
    methyl
    Protoxin-II W7Q W30Y 734 YCQKWMQTCDSERKCCE
    W7Q W30Y GMVCRLWCKKKLY-COOH
    Protoxin-II W7Q W30F 735 YCQKWMQTCDSERKCCE
    W7Q W30F GMVCRLWCKKKLF-
    COOH
    Protoxin-II W7Q W30norvaline 736 YCQKWMQTCDSERKCCE
    W7Q W30norvaline GMVCRLWCKKL-(L-
    norvaline)--COOH
  • The resulting variants incorporating non-natural amino acids are generated by standard solid-phase peptide synthesis and oxidative refolding methods.
  • The variants having a polyethylene glycol (PEG) group attached are generated via standard chemical conjugation methods.
  • The resulting variants are tested for their ability to inhibit Nav1.7 in veratridine-induced depolarization inhibition assay and QPatch assays as described in Example 3.
  • The generated variants are tested for their selectivity using methods described in Example 3.

Claims (24)

What is claimed is:
1. A method of treating Nav1.7-mediated pain in a subject, comprising administering to a subject in need thereof an effective amount of a pharmaceutical composition, wherein the pharmaceutical composition comprises:
(a) an isolated Protoxin-II variant or a fusion protein thereof to treat the pain, wherein the Protoxin-II variant has at least one amino acid substitution selected from the group consisting of W7Q and W30L; wherein residue numbering is according to SEQ ID NO: 1; and
(b) a pharmaceutically acceptable excipient.
2. A method of treating Nav1.7-mediated pain in a subject, comprising administering to a subject in need thereof an effective amount of a pharmaceutical composition, wherein the pharmaceutical composition comprises:
(a) an isolated Protoxin-II variant or a fusion protein thereof, wherein the Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 1×10−7 M or less, about 1×10−8 M or less, about 1×10−9 M or less, about 1×10−10 M or less, about 1×10−11 M or less, or about 1×10−12 M or less, wherein the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7, wherein the Protoxin-II variant has a W7Q and/or a W30L substitution, wherein residue numbering is according to SEQ ID NO: 1; and
(b) a pharmaceutically acceptable excipient.
3. The method of claim 1, wherein the isolated Protoxin-II variant comprises the sequence:
(SEQ ID NO: 432) X1X2X3CX4X5WX6QX7CX8X9X10X11X12CCX13 X14X15X16CX17LWCX18KKLX19,
wherein
X1 is G, P, A or deleted;
X2 is P, A or deleted;
X3 is S, Q, A, R or Y;
X4 is Q, R, K, A, S, or Y;
X5 is K, S, Q or R;
X6 is M or F;
X7 is T, S, R, K or Q;
X8 is D, T or asparagyl-4-aminobutane;
X9 is S, A R, I, or V;
X10 is E, R, N, K, T, Q, Y or glutamyl-4-aminobutane;
X11 is R or K;
X12 is K, Q, S, A or F;
X13 is E, Q, D, L, N or glutamyl-4-aminobutane;
X14 is G, Q or P;
X15 is M or F;
X16 is V or S;
X17 is R, T or N-omega methyl-L-arginine;
X18 is K or R; and
X19 is W or L,
optionally having an N-terminal extension or a C-terminal extension.
4. The method of claim 1, wherein the isolated Protoxin-II variant has a substitution at one or more residue positions Y1, W7, S11, E12, K14, E17, G18, R22 and L29, when residue numbering is according to SEQ ID NO: 1.
5. The method of claim 1, wherein the isolated Protoxin-II variant comprises the sequence YCQKWMQTCDSERKCCEGMVCRLWCKKKLW-OH (SEQ ID NO: 424); wherein residue Y1, S11, E12, K14, E17, G18, R22 and/or L29 is substituted with
a) any other amino acid selected from the group consisting of alanine, arginine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine;
b) a non-natural amino acid; and
c) W30 is substituted by L.
6. The method of claim 1, wherein the isolated Protoxin-II variant comprises the sequence YCQKWMQTCDSERKCCEGMVCRLWCKKKLL-OH (SEQ ID NO: 425); wherein residue Y1, S11, E12, K14, E17, G18, M19 and/or L29 is substituted with
a) any other amino acid selected from the group consisting of alanine, arginine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine; or
b) a non-natural amino acid.
7. The method of claim 1, wherein the isolated Protoxin-II variant comprises the amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 422 (GPYCQKWMQTCDSERKCCEGMVCRLWCKKKLL-COOH); wherein the residue numbering is according to SEQ ID NO: 1.
8. The method of claim 1, wherein the isolated Protoxin-II variant comprises the sequence X1X2X3CQKWMQTCDX4X5RX6CCX7X8X9VCRLWCKKKX10X11 (SEQ ID NO: 737); wherein
X1 is G, P, A or deleted;
X2 is P, A or deleted;
X3 is S, Q, A, R or Y;
X4 is S, A, R, I or V;
X5 is E, R, N, K, T, Q, Y or glutamyl-4-aminobutane;
X6 is K, Q, S, A or F;
X7 is E, Q, D, L, N or glutamyl-4-aminobutane;
X8 is G, Q or P;
X9 is M or F;
X10 is L, V; and
X11 is W or L.
9. The method of claim 1, wherein the isolated Protoxin-II variant further comprises an N-terminal extension and wherein the N-terminal extension comprises the amino acid sequence of SEQ ID NOs: 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384 or 385.
10. The method of claim 1, wherein the isolated Protoxin-II variant further comprises a C-terminal extension and wherein the C-terminal extension comprises the amino acid sequence of SEQ ID NOs: 374, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396 or 397.
11. The method of claim 1, wherein the isolated Protoxin-II variant further comprises an N-terminal extension and/or a C-terminal extension and wherein the N-terminal and/or the C-terminal extension is conjugated to the Protoxin-II variant via a linker.
12. The method of claim 11, wherein the linker comprises the amino acid sequence of SEQ ID NOs: 383, 392, 398, 399, 400, 401 or 402.
13. The method of claim 1, wherein the isolated Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of about 3×10−8 M or less, when the IC50 value is measured using a veratridine-induced depolarization inhibition assay using fluorescence resonance energy transfer (FRET) in the presence of 25×10−6 M 3-veratroylveracevine in HEK293 cells stably expressing human Nav1.7.
14. The method of claim 13, wherein the isolated Protoxin-II variant inhibits human Nav1.7 activity with an IC50 value of between about 3×10−8 M to 1×10−9 M.
15. The method of claim 1, wherein the isolated Protoxin-II variant inhibits Nav1.7 activity by at least 25%, when the Nav1.7 activity is measured using a patch clamp assay using an extracellular solution containing 137 mM NaCl, 5.4 mM KCl, 1 mM MgCl2, 2 mM CaCl2, 5 mM glucose, and 10 mM HEPES, pH=7.4, and osmolarity=315 mOsm, an intracellular solution containing 135 mM CsF, 10 mM CsCl, 5 mM EGTA, 5 mM NaCl and 10 mM HEPES, pH=7.3 and osmolarity=290 mOsm and a holding potential of −75 mV.
16. The method of claim 1, wherein the isolated Protoxin-II variant comprises the amino acid sequence
(SEQ ID NO: 433) GPQCX1X2WX3QX4CX5X6X7X8X9CCX10 X11FX12CX13LWCX14KKLL,
wherein
X1 is Q, R, K, A or S;
X2 is K, S, Q or R;
X3 is M or F;
X4 is T, S, R, K or Q;
X5 is D or T;
X6 is S, A or R;
X7 is E, R, N, K, T or Q;
X8 is R or K;
X9 is K, Q, S or A;
X10 is E, Q or D;
X11 is G or Q;
X12 is V or S;
X13 is R or T; and
X14 is K or R.
17. The method of claim 1, wherein the isolated Protoxin-II variant comprises the amino acid sequence of SEQ ID NOs: 30, 40, 44, 52, 56, 59, 65, 78, 109, 110, 111, 114, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 177, 178, 179, 180, 182, 183, 184, 185, 186, 189, 190, 193, 195, 197, 199, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 224, 226, 227, 231, 232, 243. 244, 245, 247. 249, 252, 255, 258, 261, 263, 264, 265, 266, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 332, 334, 335, 336, 337, 339, 340, 341, 342, 346, 351, 358, 359, 364, 366, 367, 368, 369, 370, 371, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 434, 435, 436, 437, 438, 439, 440, 441, 442, 443, 444, 445, 446, 447, 448, 449, 450, 451, 452, 453, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463, 464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 475, 476, 477, 478, 478, 480, 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 494, 495, 496, 497, 498, 499, 500, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541, 542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554, 555, 556, 557, 558, 559, 560, 561, 562, 563, 564, 565, 566, 567, 568, 569, 570, 571, 572, 573, 574, 575, 576, 577, 578, 579, 580, 581, 582, 583, 584, 585, 586, 587, 588, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642, 643, 644, 645, 646, 647, 648, 649, 650, 651, 652, 653, 654, 655, 656, 657, 658, 659, 660, 661, 662, 663, 664, 665, 666, 667, 668, 669, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 690, 691, 692, 693, 694, 695, 696, 697, 698, 699, 700, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, 714, 715, 716, 717, 718, 719, 720, 721, 722, 723, 724, 725, 726, 727, 728, 729, 730, 731, 732, 733, 734, 735 or 736.
18. The method of claim 1, wherein the isolated Protoxin-II variant comprises a free C-terminal carboxylic acid, amide, methylamide or butylamide group.
19. The method of claim 1, wherein the isolated fusion protein is the Protoxin-II variant conjugated to a half-life extending moiety.
20. The method of claim 19, wherein the half-life extending moiety is human serum albumin (HSA), albumin binding domain (ABD), Fc or polyethylene glycol (PEG).
21. The method of claim 1, wherein the pain is chronic pain, acute pain, neuropathic pain, cancer pain, nociceptive pain, visceral pain, back pain, post-operative pain, thermal pain, phantom limb pain, or pain associated with inflammatory conditions, primary erythemalgia (PE), paroxysmal extreme pain disorder (PEPD), osteoarthritis, rheumatoid arthritis, lumbar discectomy, pancreatitis, fibromyalgia, painful diabetic neuropathy (PDN), post-herpetic neuropathy (PHN), trigeminal neuralgia (TN), spinal cord injuries or multiple sclerosis.
22. The method of claim 21, wherein the pharmaceutical composition is administered peripherally.
23. The method of claim 22, wherein the pharmaceutical composition is administered locally to a joint, spinal cord, surgical wound, sites of injury or trauma, peripheral nerve fibers, urogenital organs, or inflamed tissues.
24. The method of claim 1, wherein the subject is a human.
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Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10414808B2 (en) 2012-05-18 2019-09-17 Janssen Biotech, Inc. Huwentoxin-IV variants and methods of use
ES2841173T3 (en) 2013-10-03 2021-07-07 Janssen Biotech Inc Protoxin-II variants and methods of use
MA41642A (en) 2015-03-03 2018-01-09 Janssen Biotech Inc PROTOXIN II VARIANTS AND METHODS OF USE
MX2017012654A (en) 2015-04-02 2018-01-09 Janssen Biotech Inc Protoxin-ii variants and methods of use.
TWI724392B (en) 2018-04-06 2021-04-11 美商美國禮來大藥廠 Growth differentiation factor 15 agonist compounds and methods of using the same
CN109369784B (en) * 2018-11-14 2019-08-30 青海芬陀利华生物科技有限公司 PaTx-1 toxin and its application
WO2021252448A1 (en) * 2020-06-10 2021-12-16 Memorial Sloan Kettering Cancer Center Imaging compounds selective for nav1.7

Family Cites Families (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4309989A (en) 1976-02-09 1982-01-12 The Curators Of The University Of Missouri Topical application of medication by ultrasound with coupling agent
US4767402A (en) 1986-07-08 1988-08-30 Massachusetts Institute Of Technology Ultrasound enhancement of transdermal drug delivery
ATE484572T1 (en) 1997-04-16 2010-10-15 Unigene Lab Inc DIRECT EXPRESSION OF PEPTIDES INTO CULTURE MEDIA
IL120943A (en) 1997-05-29 2004-03-28 Univ Ben Gurion Transdermal delivery system
US6670127B2 (en) 1997-09-16 2003-12-30 Egea Biosciences, Inc. Method for assembly of a polynucleotide encoding a target polypeptide
DE69841578D1 (en) 1997-09-16 2010-05-06 Centocor Inc Methods for complete chemical synthesis and composition of genes and genomes
US20030148273A1 (en) * 2000-08-26 2003-08-07 Shoulian Dong Target enrichment and amplification
EP1348466A3 (en) 2002-02-01 2003-10-29 Inspire Pharmaceuticals, Inc. Method for treating pain with adenosine-tetraphosphates
US7659082B2 (en) 2002-02-19 2010-02-09 Xenon Pharmaceuticals Inc. Methods for identifying analgesic agents
US7833979B2 (en) 2005-04-22 2010-11-16 Amgen Inc. Toxin peptide therapeutic agents
CA2626584A1 (en) 2005-11-04 2007-05-18 Alnylam Pharmaceuticals, Inc. Compositions and methods for inhibiting expression of nav1.8 gene
WO2007109324A2 (en) 2006-03-21 2007-09-27 Xenon Pharmaceuticals, Inc. Potent and selective nav 1.7 sodium channel blockers
BRPI0716228A2 (en) 2006-09-08 2013-10-15 Mayo Foundation AQUARETTIC AND NATURURTIC POLYPEPTIDES LACKING VASODILATOR ACTIVITY
WO2008033564A1 (en) 2006-09-15 2008-03-20 Hydra Biosciences Inc. Compounds for modulating trpv3 function
WO2008088422A2 (en) 2006-10-25 2008-07-24 Amgen Inc. Toxin peptide therapeutic agents
AU2009288088B2 (en) 2008-09-03 2014-12-04 Nono Inc. Agents and methods for treatment of pain
WO2010104115A1 (en) 2009-03-10 2010-09-16 独立行政法人産業技術総合研究所 Method for preparing polypeptide specifically recognizing membrane protein
JP5555891B2 (en) 2009-09-15 2014-07-23 アロモネ プリクリニカル リミテッド Novel peptides isolated from spider venom and uses thereof
JP5795341B2 (en) 2010-03-08 2015-10-14 デイナ ファーバー キャンサー インスティチュート，インコーポレイテッド FullCOLD-PCR enrichment with reference block sequence
US9279003B2 (en) * 2010-07-07 2016-03-08 Purdue Pharma L.P. Analogs of sodium channel peptide toxin
CN101979411A (en) 2010-10-21 2011-02-23 湖南师范大学 Huwen tarantula protease inhibitor
EA201370161A1 (en) 2011-01-18 2013-12-30 Амген Инк. KNOKAUTNYE ON Na1.7 MOUSE AND THEIR USE
WO2012151560A2 (en) 2011-05-04 2012-11-08 Biocept, Inc. Methods for detecting nucleic acid sequence variants
US10414808B2 (en) 2012-05-18 2019-09-17 Janssen Biotech, Inc. Huwentoxin-IV variants and methods of use
EP2852397B1 (en) 2012-05-18 2022-02-16 Janssen Biotech, Inc. Huwentoxin-iv variants and methods of use
US9102751B2 (en) 2012-05-18 2015-08-11 Janssen Biotech, Inc. Huwentoxin-IV variants and methods of use
WO2014016673A1 (en) 2012-07-27 2014-01-30 Purdue Pharma L.P. Sodium channel blocking peptides and the use thereof
US10344060B2 (en) 2013-03-12 2019-07-09 Amgen Inc. Potent and selective inhibitors of Nav1.7
CN104065367B (en) 2013-03-20 2017-11-07 江苏多维科技有限公司 A kind of low-watt consumption magnetic resistance switch sensor
ES2841173T3 (en) * 2013-10-03 2021-07-07 Janssen Biotech Inc Protoxin-II variants and methods of use
MA41642A (en) * 2015-03-03 2018-01-09 Janssen Biotech Inc PROTOXIN II VARIANTS AND METHODS OF USE
MX2017012654A (en) 2015-04-02 2018-01-09 Janssen Biotech Inc Protoxin-ii variants and methods of use.

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