WO2022005117A1 - Anti-sars-cov-2 s protein antibody or antigen-binding fragment thereof, and pharmaceutical composition for preventing or treating sars-cov-2 infection comprising same - Google Patents

Abstract

The present invention relates to an anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof, and a pharmaceutical composition for treating COVID-19 comprising same. The anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention can be usefully used as a therapeutic agent for COVID-19 since the same binds specifically to a S protein, which plays an important role in the infiltration of SARS-CoV-2 into host cells, so as to inhibit infection with SARS-CoV-2.

Description

Anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof, and pharmaceutical composition for preventing or treating SARS-CoV-2 infection comprising the same

This patent application claims priority to Korean Patent Application No. 10-2020-0081179, filed with the Korean Intellectual Property Office on July 1, 2020, the disclosure of which is incorporated herein by reference.

The present invention relates to an anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof, and a pharmaceutical composition for preventing or treating SARS-CoV-2 infection comprising the same.

Efforts are being made worldwide to develop a treatment for the novel coronavirus infection-19 (COVID-19), which recently occurred in Wuhan, China and is spreading around the world. In particular, when the spike protein (S protein) of SARS-CoV-2 binds to the receptor of the host cell, SARS-CoV-2 penetrates into the host cell by endocytosis. Attempts to treat COVID-19 using monoclonal antibodies to the spike protein of 2 and convalescent plasma of convalescent patients are being actively made.

The present inventors made intensive research efforts to develop a pharmaceutical composition for the prevention or treatment of COVID-19. As a result, a novel anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof was developed, it was confirmed that these antibodies or antigen-binding fragment exhibited neutralizing ability to SARS-CoV-2, and the present invention was completed. .

Accordingly, it is an object of the present invention to provide a novel anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof.

Another object of the present invention is to provide a nucleic acid molecule comprising a nucleotide sequence encoding the antibody or antigen-binding fragment thereof.

Another object of the present invention is to provide a recombinant vector comprising the nucleic acid molecule.

Another object of the present invention is to provide a host cell transformed with the recombinant vector.

Another object of the present invention is to provide a pharmaceutical composition for preventing or treating SARS-CoV-2 infection, comprising the antibody or antigen-binding fragment thereof and a pharmaceutically acceptable carrier.

According to one aspect of the present invention, the present invention provides an antibody or antigen-binding fragment thereof of an anti-SARS-CoV-2 S protein selected from:

(a) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 1, HCDR2 of SEQ ID NO: 2, and HCDR3 of SEQ ID NO: 3; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 4, LCDR2 of SEQ ID NO: 5, and LCDR3 of SEQ ID NO: 6;

(b) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 17, HCDR2 of SEQ ID NO: 18, and HCDR3 of SEQ ID NO: 19; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 20, LCDR2 of SEQ ID NO: 21, and LCDR3 of SEQ ID NO: 22;

(c) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 36, LCDR2 of SEQ ID NO: 37, and LCDR3 of SEQ ID NO: 38;

(d) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 49, HCDR2 of SEQ ID NO: 50, and HCDR3 of SEQ ID NO: 51; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 52, LCDR2 of SEQ ID NO: 53, and LCDR3 of SEQ ID NO: 54;

(e) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 65, HCDR2 of SEQ ID NO: 66, and HCDR3 of SEQ ID NO: 67; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70; or

(f) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 81, HCDR2 of SEQ ID NO: 82, and HCDR3 of SEQ ID NO: 83; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 84, LCDR2 of SEQ ID NO: 85, and LCDR3 of SEQ ID NO: 86.

In one embodiment of the present invention, the heavy chain variable region of (a) comprises the amino acid sequence of SEQ ID NO: 7, and the light chain variable region of (a) comprises the amino acid sequence of SEQ ID NO: 8.

In one embodiment of the present invention, the heavy chain variable region of (b) comprises the amino acid sequence of SEQ ID NO: 23, and the light chain variable region of (b) comprises the amino acid sequence of SEQ ID NO: 24.

In one embodiment of the present invention, the heavy chain variable region of (c) includes the amino acid sequence of SEQ ID NO: 39, and the light chain variable region of (c) includes the amino acid sequence of SEQ ID NO: 40.

In one embodiment of the present invention, the heavy chain variable region of (d) comprises the amino acid sequence of SEQ ID NO: 55, and the light chain variable region of (d) comprises the amino acid sequence of SEQ ID NO: 56.

In one embodiment of the present invention, the heavy chain variable region of (e) includes the amino acid sequence of SEQ ID NO: 71, and the light chain variable region of (e) includes the amino acid sequence of SEQ ID NO: 72.

In one embodiment of the present invention, the heavy chain variable region of (f) comprises the amino acid sequence of SEQ ID NO: 87, and the light chain variable region of (f) comprises the amino acid sequence of SEQ ID NO: 88.

In one embodiment of the present invention, the anti-SARS-CoV-2 S protein antibody of the present invention binds to a receptor binding domain (RBD) of the SARS-CoV-2 S protein.

In a specific embodiment of the present invention, the RBD of the SARS-CoV-2 S protein comprises the amino acid sequence of SEQ ID NO: 97.

In a specific embodiment of the present invention, a receptor binding motif (RBM) in the RBD of the SARS-CoV-2 S protein to which the anti-SARS-CoV-2 S protein antibody binds is selected from among the amino acid sequences of SEQ ID NO: 97, 114 to 115, 117, 119-122, 128, 131-132, 134-136, 138, 146-154, 157-162, 166, 169-170, 174-175, 177, and 179th amino acid residues.

In one embodiment of the present invention, the anti-SARS-CoV-2 S protein antibody of the present invention inhibits the binding of SARS-CoV-2 S protein to RBD and human angiotensin converting enzyme 2 (ACE2).

As used herein, the term “antibody” refers to a specific antibody against SARS-CoV S protein, and includes not only a complete antibody form but also an antigen binding fragment of an antibody molecule.

A complete antibody has a structure having two full-length light chains and two full-length heavy chains, and each light chain is linked to a heavy chain by a disulfide bond. The heavy chain constant region has gamma (γ), mu (μ), alpha (α), delta (δ) and epsilon (ε) types and subclasses gamma 1 (γ1), gamma 2 (γ2), gamma 3 (γ3). ), gamma 4 (γ4), alpha 1 (α1) and alpha 2 (α2). The constant region of the light chain has a kappa (κ) and a lambda (λ) type.

As used herein, the term "antigen binding fragment" refers to a fragment having an antigen-binding function, and includes Fab, F(ab'), F(ab') ₂ and Fv. Among antibody fragments, Fab (fragment antigen binding) has a structure having a light chain and heavy chain variable regions, a light chain constant region and a first constant region (CH1) of a heavy chain, and has one antigen-binding site. Fab' differs from Fab in that it has a hinge region comprising one or more cysteine residues at the C-terminus of the heavy chain CH1 domain. The F(ab') ₂ antibody is produced by forming a disulfide bond with a cysteine residue in the hinge region of Fab'. Fv is a minimal antibody fragment having only a heavy chain variable region and a light chain variable region, and a recombinant technique for generating an Fv fragment is known in the art. In a double-chain Fv (two-chain Fv), the heavy chain variable region and the light chain variable region are connected by a non-covalent bond, and single-chain Fv (single-chin variable fragment, scFv) is generally a heavy chain variable region and a single chain variable region through a peptide linker. The regions may be linked by a covalent bond or linked directly at the C-terminus to form a dimer-like structure like a double-stranded Fv. Such antibody fragments can be obtained using proteolytic enzymes (e.g., papain-restricted cleavage of the whole antibody gives Fab and pepsin cleavage gives F(ab') ₂ fragments), or It can be produced through genetic recombination technology.

Accordingly, in the present invention, the antibody is specifically a monoclonal antibody, a multispecific antibody, a human antibody, a humanized antibody, a chimeric antibody, a single chain Fvs (scFv), a single chain antibody, a Fab fragment, a F (ab') fragment, a disulfide-bonded antibody. Fvs (sdFv) and anti-idiotypic (anti-Id) antibodies, and epitope-binding fragments of such antibodies, and the like.

As used herein, the term “heavy chain” refers to a full-length heavy chain comprising a variable region domain VH comprising an amino acid sequence having a sufficient variable region sequence to confer specificity to an antigen and three constant region domains CH1, CH2 and CH3, and a full-length heavy chain thereof It means all fragments. In addition, the term "light chain" herein is a full-length mean both the light chain and fragments thereof containing the variable region domain, V _L, and a constant region domain, C _L comprises an amino acid sequence having sufficient variable region sequence to impart specificity to the antigen do.

As used herein, the term “variable region” or “variable domain” refers to a domain of an antibody heavy or light chain that is involved in binding an antibody to an antigen. The variable domains of the heavy and light chains of native antibodies (VH and VL, respectively) generally have a similar structure, and each domain has four conserved framework regions (FR) and three hypervariable regions (HVR). ) is included. (Kindt et al., Kuby Immunology, 6th ed., W.H. Freeman and Co., page 91 (2007)).

As used herein, the term “complementarity determining region (CDR)” refers to an amino acid sequence of a hypervariable region of an immunoglobulin heavy chain and light chain (Kabat et al., Sequences of Proteins of Immunological Interest, 4th Ed., US Department of Health and Human Services, National Institutes of Health (1987)). The heavy (HCDR1, HCDR2 and HCDR3) and light chains (LCDR1, LCDR2 and LCDR3) each contain three CDRs. CDRs provide key contact residues for the binding of an antibody to an antigen or epitope.

As used herein, the term “Framework” or “FR” refers to variable domain residues other than hypervariable region (HVR) residues. The FRs of a variable domain generally consist of the four FR domains FR1, FR2, FR3 and FR4. Thus, HVR and FR sequences generally appear in the following order in VH:

FRH1 (Framework region 1 of Heavy chain)-HCDR1 (complementarity determining region 1 of Heavy chain)-FRH2-HCDR2-FRH3-HCDR3-FRH4;

In addition, the HVR and FR sequences usually appear in the VL (or Vk) in the following order:

FRL1 (Framework region 1 of Light chain)-LCDR1 (complementarity determining region 1 of Light chain)-FRL2-LCDR2-FRL3-LCDR3-FRL4.

As used herein, the term “specifically binds” or the like means that an antibody or antigen-binding fragment thereof, or other construct such as an scFv, forms a complex with an antigen that is relatively stable under physiological conditions. Specific binding may be characterized by an equilibrium dissociation constant of at least about 1 x 10 ^-6 M or less (eg, a K _D less than this indicates a tighter binding). Methods for determining whether two molecules specifically bind are well known in the art and include, for example, equilibrium dialysis, surface plasmon resonance, and the like.

As used herein, the term “affinity” refers to the strength of the sum total of non-covalent interactions between a single binding site of a molecule (eg, an antibody) and its binding partner (eg, an antigen). Unless otherwise specified, "binding affinity" refers to intrinsic binding affinity that reflects a 1:1 interaction between members of a binding pair (eg, antibody and antigen) Molecule X and its partner The affinity of Y can generally be _{expressed as the dissociation constant (K D} ) Affinity can be measured by conventional methods known in the art, including those described herein.

Also herein, the term "human antibody" or "humanized antibody" refers to antibodies produced by humans or human cells, or non-human using human antibody repertoires or other human antibody coding sequences. It has an amino acid sequence corresponding to the amino acid sequence of the antibody from which it was derived.

As used herein, the term "chimeric antibody" means that a portion of a heavy and/or light chain is derived from a particular source or species, and the remainder of the heavy and/or light chain is derived from a different source or species. means antibodies.

The anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof of the present invention is a variant of the amino acid sequence within a range capable of specifically recognizing SARS-CoV-2 S protein, as recognized by those skilled in the art. may include For example, changes can be made to the amino acid sequence of an antibody to improve its binding affinity and/or other biological properties. Such modifications include, for example, deletions, insertions and/or substitutions of amino acid sequence residues of the antibody.

Such amino acid variations are made based on the relative similarity of amino acid side chain substituents, such as hydrophobicity, hydrophilicity, charge, size, and the like. According to the analysis of the size, shape and type of amino acid side chain substituents, arginine, lysine and histidine are all positively charged residues; alanine, glycine and serine have similar sizes; It can be seen that phenylalanine, tryptophan and tyrosine have similar shapes. Therefore, based on these considerations, arginine, lysine and histidine; alanine, glycine and serine; And phenylalanine, tryptophan and tyrosine can be said to be biologically functional equivalents.

In introducing the amino acid mutation, the hydropathic index of the amino acid may be considered. Each amino acid is assigned a hydrophobicity index according to its hydrophobicity and charge: isoleucine (+4.5); valine (+4.2); leucine (+3.8); phenylalanine (+2.8); cysteine/cysteine (+2.5); methionine (+1.9); alanine (+1.8); glycine (-0.4); threonine (-0.7); serine (-0.8); tryptophan (-0.9); tyrosine (-1.3); proline (-1.6); histidine (-3.2); glutamate (-3.5); glutamine (-3.5); aspartate (-3.5); asparagine (-3.5); lysine (-3.9); and arginine (-4.5).

The hydrophobic amino acid index is very important in conferring an interactive biological function of a protein. It is a known fact that amino acids having a similar hydrophobicity index must be substituted to retain similar biological activity. When introducing a mutation with reference to the hydrophobicity index, the substitution is made between amino acids that show a difference in the hydrophobicity index, preferably within ±2, more preferably within ±1, and even more preferably within ±0.5.

On the other hand, it is also well known that substitution between amino acids having similar hydrophilicity values results in proteins having equivalent biological activity. As disclosed in US Pat. No. 4,554,101, the following hydrophilicity values are assigned to each amino acid residue: arginine (+3.0); lysine (+3.0); Aspartate (+3.0±1); glutamate (+3.0±1); serine (+0.3); asparagine (+0.2); glutamine (+0.2); glycine (0); threonine (-0.4); proline (-0.5 ± 1); alanine (-0.5); histidine (-0.5); cysteine (-1.0); methionine (-1.3); valine (-1.5); leucine (-1.8); isoleucine (-1.8); tyrosine (-2.3); phenylalanine (-2.5); Tryptophan (-3.4).

When the mutation is introduced with reference to the hydrophilicity value, the substitution is made between amino acids exhibiting a difference in the hydrophilicity value within preferably ±2, more preferably within ±1, and even more preferably within ±0.5.

Amino acid exchanges in proteins that do not entirely alter the activity of the molecule are known in the art (H. Neurath, R.L. Hill, The Proteins, Academic Press, New York, 1979). The most common exchanges are amino acid residues Ala/Ser, Val/Ile, Asp/Glu, Thr/Ser, Ala/Gly, Ala/Thr, Ser/Asn, Ala/Val, Ser/Gly, Thy/Phe, Ala/ It is an exchange between Pro, Lys/Arg, Asp/Asn, Leu/Ile, Leu/Val, Ala/Glu, Asp/Gly.

The anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof of the present invention is an anti-SARS containing a small change to the above-described amino acid sequence, that is, a modification that has little effect on the tertiary structure and function of the antibody. -CoV-2 S antibody or antigen-binding fragment thereof. Therefore, in some embodiments, even if it does not match the above-mentioned sequence, it may have at least 90%, 93%, 95%, or 98% or more similarity.

According to one embodiment of the present invention, the anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof of the present invention is a monoclonal antibody comprising a heavy chain variable region and a light chain variable region comprising the CDRs of the above-described sequences; Specific antibodies, human antibodies, humanized antibodies, chimeric antibodies, single chain Fvs (scFv), single chain antibodies, Fab fragments, F(ab') fragments, disulfide-bonded Fvs (sdFV) and anti-idiotypic (anti-Id) ) antibodies, and epitope-binding fragments of the antibodies, and the like.

In another embodiment of the present invention, the anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof of the present invention is an anti-SARS-CoV-2 S scFv. In a specific embodiment of the present invention, the heavy chain variable region and the light chain variable region included in the antibody or antigen-binding fragment thereof are (Gly-Ser)n, (Gly ₂ -Ser)n, (Gly ₃ -Ser)n or ( It is linked by a linker such as _{Gly 4 -Ser)n.} Here, n is an integer of 1 to 6, specifically 3 to 4, but is not limited thereto. The light chain variable region and heavy chain variable region of the scFv may exist in, for example, the following orientations: light chain variable region-linker-heavy chain variable region or heavy chain variable region-linker-light chain variable region.

In one embodiment of the present invention, the antibody or antigen-binding fragment has neutralizing ability against SARS-CoV-2 of S, V, or G clade.

In one embodiment of the present invention, the SARS-CoV-2 of the S clade is hCoV_19/South Korea/KCDC03/2020.

In one embodiment of the present invention, the SARS-CoV-2 of the V clade is hCoV_19/South Korea/KUMC15/2020.

In one embodiment of the present invention, the SARS-CoV-2 of the G clade is hCoV_19/South Korea/KUMC17/2020.

According to one aspect of the present invention, the present invention provides a nucleic acid molecule comprising a nucleotide sequence encoding the above-described anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof.

As used herein, the term "nucleic acid molecule" has a meaning comprehensively including DNA (gDNA and cDNA) and RNA molecules. Analogs are also included (Scheit, Nucleotide Analogs, John Wiley, New York (1980); Uhlman and Peyman, Chemical Reviews , 90:543-584 (1990)).

It is sufficient that the nucleotide sequence encoding the antibody or antigen-binding fragment thereof of the present invention, or the chimeric antigen receptor polypeptide, is a nucleotide sequence encoding an amino acid sequence constituting the chimeric antigen receptor molecule, and is not limited to any specific nucleotide sequence. It is obvious to those skilled in the art that no.

This is because, even if a nucleotide sequence mutation occurs, the protein sequence does not change when the mutated nucleotide sequence is expressed as a protein in some cases. This is called codon degeneracy. Thus, the nucleotide sequence is a functionally equivalent codon or codon encoding the same amino acid (eg, due to codon degeneracy, there are six codons for arginine or serine), or a codon encoding a biologically equivalent amino acid It contains a nucleotide sequence comprising a.

According to a specific embodiment of the present invention, a polypeptide constituting the heavy chain CDR, light chain CDR, heavy chain variable region, light chain variable region, heavy chain, or light chain of the SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention. The sequence of is listed in the appended sequence listing of the present specification.

A nucleic acid molecule of the present invention encoding an anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof is to be construed to include a nucleotide sequence exhibiting substantial identity to the above-described nucleotide sequence. The substantial identity is at least 80% when the above-described nucleotide sequence of the present invention and any other sequences are aligned as much as possible, and the aligned sequence is analyzed using an algorithm commonly used in the art. , more preferably at least 90% homology, and most preferably at least 95%, 97%, 98%, or 99% homology.

Considering the mutations having the above-described biological equivalent activity, the antibody or antigen-binding fragment of the present invention; Alternatively, a nucleic acid molecule encoding a chimeric antigen receptor polypeptide is to be construed as including a sequence exhibiting substantial identity to a sequence set forth in the Sequence Listing. The substantial identity is at least 61% when the above-described sequence of the present invention and any other sequences are aligned as much as possible, and the aligned sequence is analyzed using an algorithm commonly used in the art. means a sequence that exhibits homology, more preferably 70% homology, even more preferably 80% homology, and most preferably 90% homology. Alignment methods for sequence comparison are known in the art. Various methods and algorithms for alignment are described in Smith and Waterman, Adv. Appl. Math. 2:482 (1981) ; Needleman and Wunsch, J. Mol. Bio. 48:443 (1970); Pearson and Lipman, Methods in Mol. Biol. 24: 307-31 (1988); Higgins and Sharp, Gene 73:237-44 (1988); Higgins and Sharp, CABIOS 5:151-3 (1989); Corpet et al., Nuc. Acids Res. 16:10881-90 (1988); Huang et al., Comp. Appl. BioSci. 8:155-65 (1992) and Pearson et al., Meth. Mol. Biol. 24:307-31 (1994). The NCBI Basic Local Alignment Search Tool (BLAST) (Altschul et al., J. Mol. Biol. 215:403-10(1990)) is accessible from the National Center for Biological Information (NBCI), etc. It can be used in conjunction with sequencing programs such as blastx, tblastn and tblastx. BLAST can be accessed through the BLAST page of the ncbi website. A method for comparing sequence homology using this program can be found on the BLAST help page of the ncbi website.

According to another aspect of the present invention, the present invention provides a recombinant vector comprising a nucleic acid molecule encoding the above-described anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof.

According to one embodiment of the present invention, the expression vector is a vector into which a nucleic acid molecule encoding the anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof is inserted, and operably binds to a nucleotide sequence of the nucleic acid molecule. It is a recombinant vector for host cell expression, which is operatively linked and includes a promoter that forms an RNA molecule in a host cell and a poly A signal sequence that acts in the host cell to cause polyadenylation of the 3'-end of the RNA molecule.

As used herein, the term "operatively linked" refers to a functional linkage between a nucleic acid expression control sequence (eg, a promoter, signal sequence, or an array of transcriptional regulator binding sites) and another nucleic acid sequence, and By this, the regulatory sequence controls the transcription and/or translation of the other nucleic acid sequence.

The vector system of the present invention can be constructed through various methods known in the art, and specific methods for this are disclosed in Sambrook, et al., Molecular Cloning, A Laboratory Manual, Cold Spring Harbor Laboratory Press (2001). , this document is incorporated herein by reference.

The vectors of the present invention can typically be constructed as vectors for cloning or as vectors for expression. In addition, the vector of the present invention can be constructed using a prokaryotic cell or a eukaryotic cell as a host.

For example, the vector is an expression vector of the present invention, in the case of a prokaryotic cell as a host, the strong promoter that can proceed with the transfer (e. G., PL ^λ promoter, trp promoter, lac promoter, T7 promoter, tac promoter, and so on) , a ribosome binding site for initiation of translation and a transcription/translation termination sequence. When E. coli is used as a host cell, the promoter and operator site of the E. coli tryptophan biosynthesis pathway (Yanofsky, C., J. Bacteriol., 158:1018-1024 (1984)) and the left-handed promoter of phage λ (pL) ^{The λ} promoter, Herskowitz, I. and Hagen, D., Ann. Rev. Genet., 14:399-445 (1980)) can be used as a regulatory region.

On the other hand, vectors that can be used in the present invention include plasmids (eg, pSK349, pSC101, ColE1, pBR322, pUC8/9, pHC79, pGEX series, pET series and pUC19, etc.), phage (eg, λgt) that are often used in the art. ·λ4B, λ-Charon, λΔz1 and M13, etc.) or viruses (eg, SV40, etc.) can be manufactured.

The vector of the present invention may be fused with other sequences to facilitate purification of the polypeptide expressed therefrom. The sequence to be fused includes, for example, glutathione S-transferase (Pharmacia, USA), maltose binding protein (NEB, USA), FLAG (IBI, USA) and 6x His (hexahistidine; Quiagen, USA). Because of the additional sequences for purification, the protein expressed in the host is rapidly and easily purified via affinity chromatography.

The vector of the present invention may include an antibiotic resistance gene commonly used in the art as a selection marker, for example, ampicillin, gentamicin, carbenicillin, chloramphenicol, streptomycin, kanamycin, geneticin, neomycin and a gene for resistance to tetracycline.

On the other hand, when the vector of the present invention is an expression vector and a eukaryotic cell is a host, a promoter derived from the genome of a mammalian cell (eg, a metallotionine promoter) or a promoter derived from a mammalian virus (eg, adeno viral late promoter, vaccinia virus 7.5K promoter, SV40 promoter, cytomegalovirus promoter and tk promoter of HSV) can be used, and generally have a polyadenylation sequence as a transcription termination sequence.

Optionally, the vector may additionally carry genes encoding reporter molecules (eg, luciferase and -glucuronidase).

According to one aspect of the present invention, the present invention provides a host cell transformed with a recombinant vector.

As a host cell capable of stably and continuously cloning and expressing the vector of the present invention, any host cell known in the art may be used, for example, E. coli Origami2, E. coli JM109, E. coli BL21 (DE3 ), E. coli RR1, E. coli LE392, E. coli B, E. coli X 1776, E.coli strain, Bacillus subtilis, Bacillus strains such as Bacillus Chuo ringen systems such as E. coli W3110, and Enterobacteriaceae and strains such as Salmonella typhimurium, Serratia marcesens, and various Pseudomonas species.

In addition, when the vector of the present invention is transformed into eukaryotic cells, as host cells, yeast (Saccharomyce cerevisiae), insect cells and animal cells (eg, CHO cell line (Chinese hamster ovary), W138, BHK, COS-7, 293) , HepG2, 3T3, RIN and MDCK cell lines) can be used.

The method of delivering the vector of the present invention into a host cell is, when the host cell is a prokaryotic cell, the CaCl ₂ method (Cohen, SN et al., Proc. Natl. Acac. Sci. USA, 9:2110-2114 (1973)) ), Hanahan method (Cohen, SN et al., Proc. Natl. Acac. Sci. USA, 9:2110-2114 (1973); and Hanahan, D., J. Mol. Biol., 166:557-580). (1983)) and electroporation methods (Dower, WJ et al., Nucleic. Acids Res., 16:6127-6145 (1988)). In addition, when the host cell is a eukaryotic cell, the microinjection method (Capecchi, MR, Cell, 22:479 (1980)), the calcium phosphate precipitation method (Graham, FL et al., Virology, 52:456 (1973)), electroporation (Neumann, E. et al., EMBO J., 1:841 (1982)), liposome-mediated transfection (Wong, TK et al., Gene, 10:87 (1980)), DEAE- Dextran treatment (Gopal, Mol. Cell Biol., 5:1188-1190 (1985)), and gene bambadment (Yang et al., Proc. Natl. Acad. Sci., 87:9568-9572 (1990)) ), and the like, to inject the vector into the host cell.

In the present invention, the recombinant vector injected into the host cell can express the above-mentioned polypeptide or polypeptide complex recombined in the host cell, and in this case, a large amount of the polypeptide or polypeptide complex is obtained. For example, when the expression vector includes the lac promoter, the host cell may be treated with IPTG to induce gene expression.

The transformed host cell can be cultured by a known host cell culture method or a modified method thereof. For example, if the host cell is E. coli , a natural medium or synthetic medium can be used as the medium for culturing the transformed host cell if it contains a carbon source, nitrogen source, inorganic salt, etc. that can be efficiently used by E. coli. have. Carbon sources that can be used include carbohydrates such as glucose, fructose, sucrose; starch, a hydrolyzate of starch; organic acids such as acetic acid and propionic acid; alcohols such as ethanol, propanol, glycerol, and the like. The nitrogen source is ammonia; ammonium salts of inorganic or organic acids such as ammonium chloride, ammonium sulfate, ammonium acetate and ammonium phosphate; peptone, meat extract, yeast extract, corn steep liquor, casein hydrolyzate, soybean extract, soybean hydrolyzate; various fermented cells and their lysates; and the like. Inorganic salts include potassium dihydrogen phosphate, dipotassium hydrogen phosphate, magnesium phosphate, magnesium sulfate, sodium chloride, manganese sulfate, copper sulfate, calcium carbonate, and the like.

The culture is usually carried out under aerobic conditions, such as by shaking culture or rotation by a rotary machine. The culture temperature is preferably in the range of 10 to 40° C., and the culture time is generally 5 hours to 7 days. The pH of the medium is preferably maintained in the range of 3.0 to 9.0 during culture. The pH of the medium can be adjusted with inorganic or organic acids, alkaline solutions, urea, calcium carbonate, ammonia, and the like. During culture, if necessary, antibiotics such as ampicillin, streptomycin, chloramphenicol, kanamycin and tetracycline may be added for maintenance and expression of the recombinant vector. When culturing a host cell transformed with a recombinant expression vector having an inducible promoter, if necessary, a suitable inducer may be added to the medium. For example, if the expression vector contains the lac promoter, IPTG (isopropyl-beta-D-thiogalactopyranoside) may be added, and if the expression vector contains a trp promoter, indoleacrylic acid may be added to the medium.

According to another aspect of the present invention, the present invention provides a polypeptide complex in which the above-described anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof and an additional polypeptide are linked.

In this case, the polypeptide complex is a multimeric form in which monomers of each polypeptide or antigen or antigen-binding fragment are linked. The polypeptide complex of the present invention is covalently linked to each other, and according to one embodiment of the present invention, the polypeptide complex may be implemented in the form of a fused protein or a conjugate.

In one embodiment of the present invention, the polypeptide complex may be implemented in the form of a fused protein or a conjugate. Thus, the antibody or antigen-binding fragment thereof and the affibody molecule may be prepared by chemical conjugation (known as organic chemistry methods) or other means (eg, expressing the complex as a fusion protein, directly or using a linker (eg, an amino acid linker) can be connected indirectly through

According to a specific embodiment of the present invention, each polypeptide monomer constituting the polypeptide complex is connected by at least one linker. In this case, the linker may consist of an amino acid sequence represented by the general formula (GnSm)p or (SmGn)p:

wherein n, m and p are independently,

n is an integer from 1 to 7;

m is an integer from 0 to 7;

the sum of n and m is an integer less than or equal to 8; and

p is an integer from 1 to 7.

According to another specific embodiment of the present invention, the linker is n = 1 to 5, and m = 0 to 5. For a more specific embodiment, n = 4 and m = 1. In a more specific embodiment, the linker is (GGGGS) ₃ . In another embodiment, the linker is GGGGS. In another specific embodiment, the linker is VDGS. In another specific embodiment, the linker is ASGS.

According to another aspect of the present invention, there is provided a nucleic acid molecule encoding the polypeptide complex.

According to another aspect of the present invention, the present invention provides a pharmaceutical composition for preventing or treating SARS-CoV-2 infection, comprising the following antibody or antigen-binding fragment thereof and a pharmaceutically acceptable carrier:

(a) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 1, HCDR2 of SEQ ID NO: 2, and HCDR3 of SEQ ID NO: 3; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 4, LCDR2 of SEQ ID NO: 5, and LCDR3 of SEQ ID NO: 6;

(b) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 17, HCDR2 of SEQ ID NO: 18, and HCDR3 of SEQ ID NO: 19; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 20, LCDR2 of SEQ ID NO: 21, and LCDR3 of SEQ ID NO: 22;

(c) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 36, LCDR2 of SEQ ID NO: 37, and LCDR3 of SEQ ID NO: 38;

(d) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 49, HCDR2 of SEQ ID NO: 50, and HCDR3 of SEQ ID NO: 51; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 52, LCDR2 of SEQ ID NO: 53, and LCDR3 of SEQ ID NO: 54;

(e) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 65, HCDR2 of SEQ ID NO: 66, and HCDR3 of SEQ ID NO: 67; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70; or

(f) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 81, HCDR2 of SEQ ID NO: 82, and HCDR3 of SEQ ID NO: 83; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 84, LCDR2 of SEQ ID NO: 85, and LCDR3 of SEQ ID NO: 86.

In one embodiment of the present invention, the SARS-CoV-2 is SARS-CoV-2 of S, V, or G clade.

Since the pharmaceutical composition of the present invention uses the above-described anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof according to an aspect of the present invention as an active ingredient, the content common between the two is excessive complexity of the present specification. In order to avoid this, the description thereof is omitted.

As demonstrated in the examples below, the anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof of the present invention binds to SARS-CoV-2 virus belonging to the SARS-CoV-2 S, V, or G clade. By neutralizing the virus, it protects against intracellular infection of the virus. Accordingly, the pharmaceutical composition comprising the anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof of the present invention as an active ingredient can be usefully used for preventing or treating SARS-CoV-2 infection.

Pharmaceutically acceptable carriers included in the pharmaceutical composition of the present invention are commonly used in formulation, and include lactose, dextrose, sucrose, sorbitol, mannitol, starch, acacia gum, calcium phosphate, alginate, gelatin, calcium silicate, microcrystalline cellulose, polyvinylpyrrolidone, cellulose, water, syrup, methyl cellulose, methylhydroxybenzoate, propylhydroxybenzoate, talc, magnesium stearate, and mineral oil; it is not going to be The pharmaceutical composition of the present invention may further include a lubricant, a wetting agent, a sweetening agent, a flavoring agent, an emulsifying agent, a suspending agent, a preservative, and the like, in addition to the above components. Suitable pharmaceutically acceptable carriers and agents are described in detail in Remington's Pharmaceutical Sciences (19th ed., 1995).

The pharmaceutical composition of the present invention may be administered orally or parenterally, such as intravenous injection, subcutaneous injection, intramuscular injection, intraperitoneal injection, intrasternal injection, intratumoral injection, topical administration, intranasal administration, intrapulmonary administration and rectal administration. etc. can be administered.

A suitable dosage of the pharmaceutical composition of the present invention varies depending on factors such as formulation method, administration mode, age, weight, sex, morbidity, food, administration time, administration route, excretion rate, and response sensitivity of the patient, An ordinarily skilled physician can readily determine and prescribe a dosage effective for the desired treatment or prophylaxis. According to a preferred embodiment of the present invention, the daily dose of the pharmaceutical composition of the present invention is 0.0001-100 mg/kg. As used herein, the term “pharmaceutically effective amount” refers to an amount sufficient to prevent or treat the aforementioned diseases.

As used herein, the term “prevention” refers to the prevention or protective treatment of a disease or disease state. As used herein, the term “treatment” refers to reduction, suppression, sedation or eradication of a disease state.

The pharmaceutical composition of the present invention is prepared in unit dosage form by formulating using a pharmaceutically acceptable carrier and/or excipient according to a method that can be easily carried out by a person of ordinary skill in the art to which the present invention pertains. or it may be prepared by incorporation into a multi-dose container. In this case, the formulation may be in the form of a solution, suspension or emulsion in oil or aqueous medium, or may be in the form of an extract, powder, suppository, powder, granule, tablet or capsule, and may additionally include a dispersing agent or stabilizer.

According to another aspect of the present invention, the present invention provides a polypeptide complex to which the above-described anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof and an additional polypeptide are linked; And it provides a pharmaceutical composition for preventing or treating SARS-CoV-2 infection, comprising a pharmaceutically acceptable carrier.

Since the pharmaceutical composition uses the above-described polypeptide complex according to an aspect of the present invention as an active ingredient, common content between the two is omitted in order to avoid excessive complexity of the present specification.

According to another aspect of the present invention, the present invention provides a method for preventing or treating SARS-CoV-2 infection, comprising administering the above-described pharmaceutical composition to a subject in need of treatment.

In one embodiment of the present invention, the pharmaceutical composition comprises the above-described anti-SARS-CoV-2 S antibody or antigen-binding fragment thereof as an active ingredient, or the above-described anti-SARS-CoV-2 S antibody or It contains an antigen-binding fragment thereof and a polypeptide complex to which an additional polypeptide is linked as an active ingredient.

In one embodiment of the present invention, the subject is a mammal or a human. The mammal includes, but is not limited to, dogs, cats, cattle, horses, pigs, sheep, and non-human primates.

Since the method for preventing or treating SARS-CoV-2 infection of the present invention includes administering the pharmaceutical composition according to one aspect of the present invention to a subject in need of treatment, the common content among them is excessive complexity of the present specification In order to avoid this, the description thereof is omitted.

The anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention specifically binds to the S protein, which plays an important role in infiltrating SARS-CoV-2 into host cells, thereby causing SARS-CoV-2 infection. Because it can inhibit the disease, it can be usefully used as a therapeutic agent for COVID-19.

1 is a diagram showing SDS-PAGE analysis of SARS-CoV-2 RBD (receptor binding domain) and NTD recombinant protein.

2 and 3 are diagrams showing the binding activity of the anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention.

4 is a PRNT assay for SARS-CoV of six antibodies (R1, R3, R4, R9, R15, and R17) of the anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention. A diagram showing the results of measuring the number of viral plaques by a reduction neutralization test).

5 is a PRNT measurement method for SARS-CoV of S, V, and G clades of three types of antibodies (R1, R3, and R4) among the anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention. It is a diagram showing the result of measuring neutralization ability (%) from (plaque reduction neutralization test).

Figure 6a is a diagram showing the binding characteristics of the RBD of the SARS-CoV-2 S protein and human ACE2 protein, Figure 6b is an anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof of the present invention (R1, R3) , R4, and R15) are diagrams showing that SARS-CoV-2 S protein inhibits binding between RBD and human ACE2 protein.

Figures 7a and 7b are anti-SARS-CoV-2 S protein antibodies or antigen-binding fragments thereof (R1, R3, R4, and R15) of the present invention to demonstrate the mechanism by which the neutralizing ability against the virus, Anti-SARS-CoV-2 S protein antibody or antigen-binding fragment thereof (R1, R3, R4, and R15) of the present invention binds to RBM of SARS-CoV-2 (FIG. 7a: SARS-CoV-2-RBD ), does not bind to the RBM of SARS-CoV (FIG. 7b: SARS-CoV-2-chRBD).

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention in more detail, and it will be apparent to those of ordinary skill in the art that the scope of the present invention is not limited by these examples according to the gist of the present invention. .

Example

Throughout this specification, "%" used to indicate the concentration of a specific substance is (weight/weight) % for solid/solid, (weight/volume) % for solid/liquid, and Liquid/liquid is (volume/volume) %.

Example 1. SARS-CoV-2 RBD and NTD protein production using animal cells

Recombinant proteins for receptor binding domain (RBD) and N-terminal domain (NTD) regions of SARS-CoV-2 virus spike protein were produced in the form of mouse Fc (mFc) fusion protein using HEK293F cells.

Expression vectors for SARS-CoV-2 RBD and NTD recombinant proteins were prepared as follows. SARS-CoV-2 RBD (Genbank: MN908947.3) and NTD (Genbank: MN908947.3) genes and mouse Fc gene (UniProtKB: P01863) were prepared by requesting synthesis from Bionics. The synthesized gene was prepared in the form of RBD-mFc and NTD-mFc through overlapping PCR, and then KpnI (NEB, Cat. #. R0142L) and XhoI (NEB) in pcDNA3.3 vector (Invitrogen, cat. #. K8300-01) , cat. #. R0146L), an expression vector was prepared by cloning the gene with a restriction enzyme.

HEK293F cells were grown in ^{an amount of 100mL at a concentration of 1 x 10 6} cells/mL, and then HEK 293F was _{shaken cultured at 37°C, 8% CO 2} , and RPM 125 conditions. 5mL of culture medium was put into a sterile 15mL tube, and RBD and NTD recombinant protein expression vector DNA were added and mixed well to prepare DNA. PEI (Polysciences, cat. #. 23966) was put in a 15 mL tube with culture medium and DNA, mixed well, and put into HEK293F cells, and cultured for 7 days. The recombinant protein in the culture medium was purified using Protein A resin (GE healthcare, cat. #. 17-5438-03), and the buffer was replaced using the diafiltation method (Satorius, cat. #. VS2002). The purified recombinant protein was quantified by measuring the absorbance at an absorbance of 280. The purified recombinant protein was analyzed by 12% SDS-PAGE (FIG. 1).

Example 2. Selection of human antibody specific for SARS-CoV-2 spike protein

As a result of bio-panning selection of human antibodies that specifically bind to the spike protein, which plays a key role in the process of SARS-CoV-2 virus entering human cells, 59 types of antibodies specifically binding to the spike protein were identified. was selected.

The bio-panning screening for the selection of human antibodies that specifically bind to the spike protein was performed as follows. SARS-CoV S1 (Sino Biological, Cat. #. 40150-V08B1) and SARS-CoV-2 S1 (Sino Biological, Cat. #. 40591-V08H) antigens used for bio-panning were purchased from Sino Biological and used. . NTD and RBD antigens were produced and used as recombinant proteins in the form of mouse Fc fusion as described in Example-1. The human antibody library (patent application number: 10-2014-0195243) was rescued in phage form using VCSM13 helper phage and used for panning. The number of library phages binding to the first antigen was 10 ¹³ . The panning round was carried out up to 4 rounds, and as a panning strategy in which phages with high affinity could be selectively and well selected, the amount of antigen was reduced and the number of washes increased as the number of panning rounds increased. The number of phages bound to the target antigen was titrated using ER2537 E. coli as follows. The binder phage obtained in each round of bio-panning was elution with Glycine-HCl buffer (pH 2.5). ER2537 cultured overnight in SB media (MOPS 10 g/L, Bacto YEAST extract 20 g/L, Trypton 30 g/L) was passaged at 1/200 dilution in fresh SB media, and then incubated at 37°C for 3 hours. to reach the log phage. 100 μL of fresh ER2537 and 10 μL of dilution phage were mixed in a 1.5 mL tube, incubated for 30 minutes, spread on an ampicillin LB plate, and cultured overnight at 37°C. The number of phages was measured. The binder phage obtained in each round of bio-panning was infected with ER2537 and maintained in the form of a colony, and binding to each antigen was checked by the ELISA method as follows. Colonies obtained by infecting binder phage were inoculated into SB media and then _{cultured at OD 600} until 0.5, 0.5 mM IPTG (LPS solution) was added, and shaking incubated at 30°C to overexpress scFv protein. Periplasmic extraction was performed using BBS buffer (200 mM Boric acid, 150 mM NaCl, 1 mM EDTA). The extracted scFv antibody was treated on a plate coated with SARS-CoV-2 S1 recombinant protein, and ant-HA mouse HRP (Roche, cat. #. 12013819001) was treated with a secondary antibody, followed by Absignal (AbClon, cat. #. AbC3001) was used to develop a color reaction, and then the OD ₄₅₀ value was measured and confirmed using an ELISA reader (Victor X3 PerkinElmer). The antibody clone selected to specifically bind to the SARS-CoV-2 S1 protein was obtained from a phagemid plasmid, and the nucleotide sequence of the variable region was confirmed through sequencing analysis.

Example 3. ELISA analysis to confirm binding ability to SARS-CoV-2 RBD antigen

Binder phage obtained from each round of Panning was checked for binding to antigen by ELISA method of colonies obtained by infection with ER2537. The colony obtained by infecting the binder phage was inoculated into SB media (MOPS 10 g/L, Bacto YEAST extract 20 g/L, Trypton 30 g/L) and then cultured at OD600 until 0.8, 1 mM IPTG ( LPS solution) and shaking incubated at 30 °C to overexpress scFv. ScFv was subjected to periplasmic extraction using BBS buffer (200 mM Boric acid, 150 mM NaCl, 1 mM EDTA). Using this, the binding ability to the SARS-CoV-2 antigen was confirmed through the ELISA method. In ELISA, scFv periplasmic extract was treated on a plate coated with SARS-CoV-2 RBD-mFc, SARS-CoV-2 S1, and BSA proteins at a concentration of 2 ug/mL, and then the secondary antibody (anti-HA-HRP ( Roche, 12013819001)), a color reaction was generated with TMB (biofx, TMBC-1000-01), and the OD450 value was measured using an ELISA reader (Victor X3, Perkinelmer). As a result of ELISA, 13 types of antibodies that bind to SARS-CoV-2 RBD and S1 antigen protein were identified as the primary (FIG. 2), and 34 types of antibodies that bind to SARS-CoV-2 RBD and S1 antigen protein were performed through additional ELISA analysis. and 12 types of antibodies binding to SARS-CoV-2 S1 were identified (FIG. 3).

Example 4. Confirmation of neutralizing ability of antibodies against SARS-CoV-2 virus

The SARS-CoV-2 virus neutralizing ability of the antibodies developed in Examples 1 to 3 of the present invention was evaluated by PRNT measurement (plaque reduction neutralization test). The SARS-CoV-2 virus of the S clade (hCoV_19/South Korea/KCDC03/2020) was used for neutralizing activity analysis. In the PRNT measurement method, the antibody sample stock solution is diluted 1:10 in PBS, and then diluted stepwise by 3 times, and then mixed with the same amount of virus (100 PFU/100 μl) and reacted at 37°C for 1 hour. After 1 hour of reaction, all Vero cells were infected and neutralizing antibody titers were analyzed through plaque assay. When the virus-infected plate (NEST Scientific, #703003) is _{cultured in an incubator at 37° C. 5% CO 2} for 3 days, it can be seen that a circular-shaped plaque is formed by the virus infection. To measure the number of plaques formed, it was stained with crystal violet (Georgiachem, #548-6-29). _{After staining, the neutralizing ability (PRNT 50} ) was analyzed by calculating the maximum antibody dilution factor that reduces the number of plaques by 50% or more compared to the control group not treated with the antibody. The results are shown in FIG. 4 . From the results of FIG. 4 , six types of antibodies (R1, R3, R4, R15, and R17) having the ability to neutralize SARS-CoV-2 were identified.

The amino acid sequences constituting the CDR sequences, the heavy chain variable region and the light chain variable region of the six antibodies, and the nucleotide sequences encoding them are shown in Tables 1 to 6 below.

antibody heavy chain light chain note R1 GAGGTGCAGCTGTTGGAGTCTGGGGGAGGCTTGGTACAGCCTGGGGGGTCCCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTTAGC GGTTATTCTATGAGC TGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTCTCA TACATCTCTTCTTACTACTACTCTACGTATTACGCTGATTCTGTAAAAGGT CGGTTCACCATCTCCAGAGACAATTCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAGAGCCGAGGACACGGCCGTGTATTACTGTGCGCGT TACGGTTACTCTGGTTAC TTCGACTACTGGGGCCAGGGTACACTGGTCACCGTGAGCTCA ( SEQ ID NO: 15) EVQLLESGGGLVQPGGSLRLSCAASGFTFS GYSMS WVRQAPGKGLEWVS YISSYYYSTYYADSVKG RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAR YGYSGY FDYWGQGTLVTVSS (SEQ ID NO: 7) CAGTCTGTGCTGACTCAGCCACCCTCAGCGTCTGGGACCCCCGGGCAGAGGGTCACCATCTCTTGT AGTGGCTCTTCATCTAATATTGGCTCTAATTATGTCTAC TGGTACCAGCAGCTCCCAGGAACGGCCCCCAAACTCCTCATCTAT AGAAATAACCAGCGGCCAAGC GGGGTCCCTGACCGATTCTCTGGCTCCAAGTCTGGCACCTCAGCCTCCCTGGCCATCAGTGGGCTCCGGTCCGAGGATGAGGCCGATTATTACTGT GCTGCTTCTCCGGCTTACTACTACTATGTC TTCGGCGGAGGCACCAAGCTGACGGTCCTAGGT ( SEQ ID NO: 16) QSVLTQPPSASGTPGQRVTISC SGSSSNIGSNYVY WYQQLPGTAPKLLIY RNNQRPS GVPDRFSGSKSGTSASLAISGLRSEDEADYYC AASPAYYYYV FGGGTKLTVLG (SEQ ID NO: 8) Under bar: CDR regions

antibody heavy chain light chain note R3 GAGGTGCAGTTGTTGGAGTCTGGGGGAGGCTTGGTACAGCCTGGGGGGTCCCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTTAGC TCTTATGGTATGAGC TGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTCTCA TACATCGGTGGTGGTTACGGTGGTACGTATTACGCTGATTCTGTAAAAGGT CGGTTCACCATCTCCAGAGACAATTCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAGAGCCGAGGACACGGCCGTGTATTACTGTGCGCGT TACGGTGGTTCTGCTTAC TTCGACTACTGGGGCCAGGGTACACTGGTCACCGTGAGCTCA ( SEQ ID NO: 31) EVQLLESGGGLVQPGGSLRLSCAASGFTFS SYGMS WVRQAPGKGLEWVS YIGGGYGGTYYADSVKG RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAR YGGSAY FDYWGQGTLVTVSS (SEQ ID NO: 23) CAGTCTGTGCTGACTCAGCCACCCTCAGCGTCTGGGACCCCCGGGCAGAGGGTCACCATCTCTTGT AGTGGCTCTTCATCTAATATTGGCTCTAATTATGTCTAC TGGTACCAGCAGCTCCCAGGAACGGCCCCCAAACTCCTCATCTAT AGAAATAACCAGCGGCCAAGC GGGGTCCCTGACCGATTCTCTGGCTCCAAGTCTGGCACCTCAGCCTCCCTGGCCATCAGTGGGCTCCGGTCCGAGGATGAGGCCGATTATTACTGT GCTGCTTACTACCGTTACAACCGTTATGTC TTCGGCGGAGGCACCAAGCTGACGGTCCTAGGT ( SEQ ID NO: 32) QSVLTQPPSASGTPGQRVTISC SGSSSNIGSNYVY WYQQLPGTAPKLLIY RNNQRPS GVPDRFSGSKSGTSASLAISGLRSEDEADYYC AAYYRYNRYV FGGGTKLTVLG (SEQ ID NO: 24) Under bar: CDR regions

antibody heavy chain light chain note R4 GAGGTGCAGCTGTTGGAGTCTGGGGGAGGCTTGGTACAGCCTGGGGGGTCCCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTTAGC AATTATTCTATGAGC TGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTCTCA TACATCTCTTCTTCTTACTACTCTACGTATTACGCTGATTCTGTAAAAGGT CGGTTCACCATCTCCAGAGACAATTCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAGAGCCGAGGACACGGCCGTGTATTACTGTGCGCGT TACGGTTACAACGAC TTCGACTACTGGGGCCAGGGTACACTGGTCACCGTGAGCTCA ( SEQ ID NO: 47) EVQLLESGGGLVQPGGSLRLSCAASGFTFS NYSMS WVRQAPGKGLEWVS YISSSYYSTYYADSVKG RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAR YGYND FDYWGQGTLVTVSS (SEQ ID NO: 39) CAGTCTGTGCTGACTCAGCCACCCTCAGCGTCTGGGACCCCCGGGCAGAGGGTCACCATCTCTTGT AGTGGCTCTTCATCTAATATTGGCTCTAATTATGTCTAC TGGTACCAGCAGCTCCCAGGAACGGCCCCCAAACTCCTCATCTAT AGAAATAACCAGCGGCCAAGC GGGGTCCCTGACCGATTCTCTGGCTCCAAGTCTGGCACCTCAGCCTCCCTGGCCATCAGTGGGCTCCGGTCCGAGGATGAGGCCGATTATTACTGT GCTGCTGCTCCGTCTCCTTCTTACTATGTC TTCGGCGGAGGCACCAAGCTGACGGTCCTAGGT ( SEQ ID NO: 48) QSVLTQPPSASGTPGQRVTISC SGSSSNIGSNYVY WYQQLPGTAPKLLIY RNNQRPS GVPDRFSGSKSGTSASLAISGLRSEDEADYYC AAAPSPSYYV FGGGTKLTVLG (SEQ ID NO: 40) Under bar: CDR regions

antibody heavy chain light chain note R9 GAGGTGCAGCTGTTGGAGTCTGGGGGAGGCTTGGTACAGCCTGGGGGGTCCCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTTAGC TACTATGGTATGAGC TGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTCTCA TACATCTCTTCTTACTACTCTTACACGTATTACGCTGATTCTGTAAAAGGT CGGTTCACCATCTCCAGAGACAATTCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAGAGCCGAGGACACGGCCGTGTATTACTGTGCGCGT TACGGTGGTTCTTACCCGTACGACTAC TTCGACTACTGGGGCCAGGGTACACTGGTCACCGTGAGCTCA ( SEQ ID NO: 63) EVQLLESGGGLVQPGGSLRLSCAASGFTFS YYGMS WVRQAPGKGLEWVS YISSYYSYTYYADSVKG RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAR YGGSYPYDY FDYWGQGTLVTVSS (SEQ ID NO: 55) CAGTCTGTGCTGACTCAGCCACCCTCAGCGTCTGGGACCCCCGGGCAGAGGGTCACCATCTCTTGT AGTGGCTCTTCATCTAATATTGGCTCTAATTATGTCTAC TGGTACCAGCAGCTCCCAGGAACGGCCCCCAAACTCCTCATCTAT AGAAATAACCAGCGGCCAAGC GGGGTCCCTGACCGATTCTCTGGCTCCAAGTCTGGCACCTCAGCCTCCCTGGCCATCAGTGGGCTCCGGTCCGAGGATGAGGCCGATTATTACTGT GCTGCTGCTCCGGACTACGCTTCTTATGTC TTCGGCGGAGGCACCAAGCTGACGGTCCTAGGT ( SEQ ID NO: 64) QSVLTQPPSASGTPGQRVTISC SGSSSNIGSNYVY WYQQLPGTAPKLLIY RNNQRPS GVPDRFSGSKSGTSASLAISGLRSEDEADYYC AAAPDYASYV FGGGTKLTVLG (SEQ ID NO: 56) Under bar: CDR regions

antibody heavy chain light chain note R15 GAGGTGCAGCTGTTGGAGTCTGGGGGAGGCTTGGTACAGCCTGGGGGGTCCCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTTAGC TCTTATGGTATGAGC TGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTCTCA TACATCTCTGGTTACTACTACTCTACGTATTACGCTGATTCTGTAAAAGGT CGGTTCACCATCTCCAGAGACAATTCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAGAGCCGAGGACACGGCCGTGTATTACTGTGCGCGT TACTCTTACGACTACTCTTCT TTCGACTACTGGGGCCAGGGTACACTGGTCACCGTGAGCTCA ( SEQ ID NO: 79) EVQLLESGGGLVQPGGSLRLSCAASGFTFS SYGMS WVRQAPGKGLEWVS YISGYYYSTYYADSVKG RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAR YSYDYSS FDYWGQGTLVTVSS (SEQ ID NO: 71) CAGTCTGTGCTGACTCAGCCACCCTCAGCGTCTGGGACCCCCGGGCAGAGGGTCACCATCTCTTGT AGTGGCTCTTCATCTAATATTGGCTCTAATTATGTCTAC TGGTACCAGCAGCTCCCAGGAACGGCCCCCAAACTCCTCATCTAT AGAAATAACCAGCGGCCAAGC GGGGTCCCTGACCGATTCTCTGGCTCCAAGTCTGGCACCTCAGCCTCCCTGGCCATCAGTGGGCTCCGGTCCGAGGATGAGGCCGATTATTACTGT GCTGCTTCTGCTAACGACTACTATGTC TTCGGCGGAGGCACCAAGCTGACGGTCCTAGGT ( SEQ ID NO: 80) QSVLTQPPSASGTPGQRVTISC SGSSSNIGSNYVY WYQQLPGTAPKLLIY RNNQRPS GVPDRFSGSKSGTSASLAISGLRSEDEADYYC AASANDYYV FGGGTKLTVLG (SEQ ID NO: 72) Under bar: CDR regions

antibody heavy chain light chain note R17 GAGGTGCAGCTGTTGGAGTCTGGGGGAGGCTTGGTACAGCCTGGGGGGTCCCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTTAGC AATTATTCTATGAGC TGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTCTCA TACATCTCTGGTCACTACGGTTACACGTATTACGCTGATTCTGTAAAAGGT CGGTTCACCATCTCCAGAGACAATTCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAGAGCCGAGGACACGGCCGTGTATTACTGTGCGCGT TACTCTTACTCTAAC TTCGACTACTGGGGCCAGGGTACACTGGTCACCGTGAGCTCA ( SEQ ID NO: 95) EVQLLESGGGLVQPGGSLRLSCAASGFTFS NYSMS WVRQAPGKGLEWVS YISGHYGYTYYADSVKG RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAR YSYSN FDYWGQGTLVTVSS (SEQ ID NO: 87) CAGTCTGTGCTGACTCAGCCACCCTCAGCGTCTGGGACCCCCGGGCAGAGGGTCACCATCTCTTGT AGTGGCTCTTCATCTAATATTGGCTCTAATTATGTCTAC TGGTACCAGCAGCTCCCAGGAACGGCCCCCAAACTCCTCATCTAT AGAAATAACCAGCGGCCAAGC GGGGTCCCTGACCGATTCTCTGGCTCCAAGTCTGGCACCTCAGCCTCCCTGGCCATCAGTGGGCTCCGGTCCGAGGATGAGGCCGATTATTACTGT GCTGCTTCTGGTAACTACCGTTCTTATGTC TTCGGCGGAGGCACCAAGCTGACGGTCCTAGGT ( SEQ ID NO: 96) QSVLTQPPSASGTPGQRVTISC SGSSSNIGSNYVY WYQQLPGTAPKLLIY RNNQRPS GVPDRFSGSKSGTSASLAISGLRSEDEADYYC AASGNYRSYV FGGGTKLTVLG (SEQ ID NO: 88) Under bar: CDR regions

In addition, S clade (hCoV_19/South Korea/KCDC03/2020), V clade (hCoV_19/South Korea/KUMC15/2020), G clade for three kinds of antibodies R1, R3 and R4, which have particularly excellent neutralizing ability among the six kinds of antibodies The neutralizing ability of (hCoV_19/South Korea/KUMC17/2020) against SARS-CoV-2 virus was analyzed by PRNT measurement. Neutralization capacity (%) was calculated based on the number of plaques in the wells treated with the antibody compared to the number of plaques from the wells that were not treated with the antibody (FIG. 5), and the EC ₅₀ value was derived using the Prism program (GraphPad) (Table 7).

EC ₅₀ value (μg/mL) clade Antibody R1 R3 R4 S 0.044 0.013 1.072 G 0.091 0.017 1.445 V 0.095 0.007 0.355

From the results of Table 7 and Figure 5, the three types of antibodies (R1, R3, and R4) of the present invention all have neutralizing ability against SARS-CoV-2 virus of S, G, and V clades, and therefore, of COVID-19 It was confirmed that it can be usefully used as a therapeutic agent.

Example 5. Mechanism of action and binding site analysis

The present inventors also confirmed by ELISA test whether the antibodies showing the virus neutralizing ability inhibit the binding of SARS-CoV-2 to ACE2, which is known as a cellular receptor. For the test, RBD-mFc and humanACE2-His (Bioss antibodies, bs-46001P) recombinant proteins produced using animal cells were used.

In the ELISA method, blocking was performed with 3% skim milk dissolved in PBS on a plate coated with RBD-mFc and protein at a concentration of 1 μg/mL. The blocking plate was diluted with humanACE2-His protein from 10 μg/mL to 1/4 and treated with 7 concentrations, followed by treatment with a secondary antibody (anti-His-HRP (R&D systems, MAB050H)). . Between each step, it was washed three times with PBST (0.05% Tween in PBS). Finally, a color reaction was generated with TMB (biofx, TMBC-1000-01), and the OD ₄₅₀ value was measured and confirmed using an ELISA reader (Victor X3 PerkinElmer) (FIG. 6a). Through this, it was confirmed that the RBD-mFc protein coated on the plate and the treated humanACE2-His protein were bound.

Next, the degree to which the binding between SARS-CoV-2-RBD and ACE2 was inhibited by the antibody was confirmed using the ELISA method. Among the tested antibodies, the CR3022 antibody other than the developed antibodies (R1, R3, R4, R15) binds to SARS-CoV-2 RBD, but is known to have no ACE2 neutralizing ability (Science. 2020 May 8; 368 (6491) ): 630-633). Blocking was performed with 3% skim milk dissolved in PBS on a plate coated with RBD-mFc protein at a concentration of 1 μg/mL. HumanACE2-his protein at a concentration of 0.15 μg/mL and antibodies (Negative Ab, CR3022, R1, R3, R4, and R15) at a concentration of 0.15 μg/mL and 7.5 μg/mL to 1/3 were added to the blocking plate. After treating the mixture diluted to a concentration, a secondary antibody (anti-his-HRP (R&D systems, MAB050H)) was treated. Between each step, it was washed three times with PBST (0.05% Tween in PBS). A color reaction was generated with TMB (biofx, TMBC-1000-01), and the OD ₄₅₀ value was measured and confirmed using an ELISA reader (Victor X3 PerkinElmer) (FIG. 6b). It was confirmed that the developed antibodies inhibit the binding between ACE2 and RBD.

The present inventors also analyzed the binding of the developed antibodies to the chimeric RBD protein in order to confirm the binding site in the SARS-CoV-2-RBD protein. It was confirmed that all of the previously developed antibodies did not cross-react with the S protein of SARS-CoV. Based on this, a protein expressing only the RBD portion of the SARS-CoV-2 virus spike protein (SARS-CoV-2-RBD) and a receptor (RBM) known to be directly involved in binding to ACE2 in SARS-CoV-2-RBD binding motif) to the protein (SARS-CoV-2-chRBD) in which the sequence of the SARS-CoV RBM sequence was substituted, the degree of binding of the selected antibody was confirmed. The amino acid sequences of SARS-CoV-2-RBD, SARS-CoV-RBD, and SARS-CoV-2-chRBD are shown in Table 8. Specifically, blocking was performed with 3% skim milk dissolved in PBS on a plate coated with RBD-mFc and chRBD-mFC proteins at a concentration of 1 μg/mL. After processing by diluting the purified antibody from 9 μg/mL to 1/5 in the blocking plate to a concentration of 7 steps, the secondary antibody (anti-hIgG-Fab-HRP (Jackson, JAC-109- 035-097)) was treated. Between each step, it was washed three times with PBST (0.05% Tween in PBS). Finally, a color reaction was generated with TMB (biofx, TMBC-1000-01), and the OD ₄₅₀ value was measured and confirmed using an ELISA reader (Victor X3 PerkinElmer). The results are shown in Figures 7a and 7b.

RBD region sequences of SARS-CoV-2-RBD and SARS-CoV-2-chRBD proteins division RBD region sequence SEQ ID NO: SARS-CoV-2-RBD SIVRFPNITN LCPFGEVFNA TRFASVYAWN RKRISNCVAD YSVLYNSASF STFKCYGVSP TKLNDLCFTN VYADSFVIRG DEVRQIAPGQ TGKIADYNYK LPDDFTGCVI AWN SN N L D SK VG GNYNY L YR LF R KSN L K PF ERDIS TEIYQ AGST PC NGVE GF NCY F PL QS YGF QP T N G V G YQPYRVVVLS FELLHAPATV CGPKKUnder bar: ACE2 receptor binding motif 97 SARS-CoV-RBD RVVPSGDVVRFPNITNLCPFGEVFNATKFPSVYAWDYSVLYNSTFFSTFKCYGVSATKLNDLCFSNVYADSFVVKGDDVRQIAPGQTGVIADYNYKLPDDFMGCVLAWNTRNIDATSTGNYNYKYRYLRHGKQLRPFERDISNVPFSPDGKKPCTPPALNCYWNAPPLN 98 SARS-CoV-2-chRBD SIVRFPNITNLCPFGEVFNATRFASVYAWNRKRISNCVADYSVLYNSASFSTFKCYGVSPTKLNDLCFTNVYADSFVIRGDEVRQIAPGQTGKIADYNYKLPDDFTGCVIAWNTRNIDATSTGNYNYKYRYLRHGKLRPFERDISNVPFSPDPGKPCTPPYTTIGELLHAPLNDYGPYTTIGKW 99

7A and 7B, the developed antibodies (R1, R3, R4, and R15) bind to the RBD site of the S protein of SARS-CoV-2, which directly binds to humanACE2, thereby forming a gap between the S protein and the ACE2 protein. It was confirmed that by inhibiting the binding of SARS-CoV-2 shows neutralizing ability to the virus.

Claims (10)

An antibody of an anti-SARS-CoV S protein or antigen-binding fragment thereof selected from: (a) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 1, HCDR2 of SEQ ID NO: 2, and HCDR3 of SEQ ID NO: 3; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 4, LCDR2 of SEQ ID NO: 5, and LCDR3 of SEQ ID NO: 6; (b) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 17, HCDR2 of SEQ ID NO: 18, and HCDR3 of SEQ ID NO: 19; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 20, LCDR2 of SEQ ID NO: 21, and LCDR3 of SEQ ID NO: 22; (c) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 36, LCDR2 of SEQ ID NO: 37, and LCDR3 of SEQ ID NO: 38; (d) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 49, HCDR2 of SEQ ID NO: 50, and HCDR3 of SEQ ID NO: 51; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 52, LCDR2 of SEQ ID NO: 53, and LCDR3 of SEQ ID NO: 54; (e) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 65, HCDR2 of SEQ ID NO: 66, and HCDR3 of SEQ ID NO: 67; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70; or (f) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 81, HCDR2 of SEQ ID NO: 82, and HCDR3 of SEQ ID NO: 83; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 84, LCDR2 of SEQ ID NO: 85, and LCDR3 of SEQ ID NO: 86. The antibody or antigen-binding fragment thereof according to claim 1, wherein the antibody or antigen-binding fragment has neutralizing ability for SARS-CoV-2 of S, V, or G clade. The antibody or antigen-binding fragment thereof according to claim 2, wherein the SARS-CoV-2 of the S clade is hCoV_19/South Korea/KCDC03/2020. The antibody or antigen-binding fragment thereof according to claim 2, wherein the SARS-CoV-2 of the V clade is hCoV_19/South Korea/KUMC15/2020. The antibody or antigen-binding fragment thereof according to claim 2, wherein the SARS-CoV-2 of the G clade is hCoV_19/South Korea/KUMC17/2020. A nucleic acid molecule comprising a nucleotide sequence encoding the antibody of claim 1 or an antigen-binding fragment thereof. A recombinant vector comprising the nucleic acid molecule of claim 6. A host cell transformed with the recombinant vector of claim 7. A pharmaceutical composition for preventing or treating SARS-CoV-2 infection, comprising the following antibody or antigen-binding fragment thereof and a pharmaceutically acceptable carrier: (a) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 1, HCDR2 of SEQ ID NO: 2, and HCDR3 of SEQ ID NO: 3; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 4, LCDR2 of SEQ ID NO: 5, and LCDR3 of SEQ ID NO: 6; (b) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 17, HCDR2 of SEQ ID NO: 18, and HCDR3 of SEQ ID NO: 19; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 20, LCDR2 of SEQ ID NO: 21, and LCDR3 of SEQ ID NO: 22; (c) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 36, LCDR2 of SEQ ID NO: 37, and LCDR3 of SEQ ID NO: 38; (d) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 49, HCDR2 of SEQ ID NO: 50, and HCDR3 of SEQ ID NO: 51; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 52, LCDR2 of SEQ ID NO: 53, and LCDR3 of SEQ ID NO: 54; (e) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 65, HCDR2 of SEQ ID NO: 66, and HCDR3 of SEQ ID NO: 67; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70; or (f) a heavy chain variable region comprising HCDR1 of SEQ ID NO: 81, HCDR2 of SEQ ID NO: 82, and HCDR3 of SEQ ID NO: 83; and an antibody or antigen-binding fragment thereof comprising a light chain variable region of LCDR1 of SEQ ID NO: 84, LCDR2 of SEQ ID NO: 85, and LCDR3 of SEQ ID NO: 86. The pharmaceutical composition of claim 9, wherein the SARS-CoV-2 is SARS-CoV-2 of S, V, or G clade.

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