WO2023111796A1 - Anticorps sars-cov-2 pan-spécifiques et leurs utilisations - Google Patents

Anticorps sars-cov-2 pan-spécifiques et leurs utilisations Download PDF

Info

Publication number
WO2023111796A1
WO2023111796A1 PCT/IB2022/062007 IB2022062007W WO2023111796A1 WO 2023111796 A1 WO2023111796 A1 WO 2023111796A1 IB 2022062007 W IB2022062007 W IB 2022062007W WO 2023111796 A1 WO2023111796 A1 WO 2023111796A1
Authority
WO
WIPO (PCT)
Prior art keywords
seq
antibody
antibody fragment
purified
cov
Prior art date
Application number
PCT/IB2022/062007
Other languages
English (en)
Inventor
Traian Sulea
Jason Baardsnes
Matthew Stuible
Yves Durocher
Original Assignee
National Research Council Of Canada
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by National Research Council Of Canada filed Critical National Research Council Of Canada
Publication of WO2023111796A1 publication Critical patent/WO2023111796A1/fr

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P31/00—Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
    • A61P31/12—Antivirals
    • A61P31/14—Antivirals for RNA viruses
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/08—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from viruses
    • C07K16/10—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from viruses from RNA viruses
    • C07K16/1002—Coronaviridae
    • C07K16/1003—Severe acute respiratory syndrome coronavirus 2 [SARS‐CoV‐2 or Covid-19]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00—Medicinal preparations containing antigens or antibodies
    • A61K2039/505—Medicinal preparations containing antigens or antibodies comprising antibodies
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00—Medicinal preparations containing antigens or antibodies
    • A61K2039/545—Medicinal preparations containing antigens or antibodies characterised by the dose, timing or administration schedule
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/30—Immunoglobulins specific features characterized by aspects of specificity or valency
    • C07K2317/33—Crossreactivity, e.g. for species or epitope, or lack of said crossreactivity
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
    • C07K2317/56—Immunoglobulins specific features characterized by immunoglobulin fragments variable (Fv) region, i.e. VH and/or VL
    • C07K2317/565—Complementarity determining region [CDR]
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
    • C07K2317/56—Immunoglobulins specific features characterized by immunoglobulin fragments variable (Fv) region, i.e. VH and/or VL
    • C07K2317/569—Single domain, e.g. dAb, sdAb, VHH, VNAR or nanobody®
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/70—Immunoglobulins specific features characterized by effect upon binding to a cell or to an antigen
    • C07K2317/76—Antagonist effect on antigen, e.g. neutralization or inhibition of binding
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/90—Immunoglobulins specific features characterized by (pharmaco)kinetic aspects or by stability of the immunoglobulin
    • C07K2317/92—Affinity (KD), association rate (Ka), dissociation rate (Kd) or EC50 value
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/90—Immunoglobulins specific features characterized by (pharmaco)kinetic aspects or by stability of the immunoglobulin
    • C07K2317/94—Stability, e.g. half-life, pH, temperature or enzyme-resistance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2333/00—Assays involving biological materials from specific organisms or of a specific nature
    • G01N2333/005—Assays involving biological materials from specific organisms or of a specific nature from viruses
    • G01N2333/08—RNA viruses
    • G01N2333/165—Coronaviridae, e.g. avian infectious bronchitis virus
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2469/00—Immunoassays for the detection of microorganisms
    • G01N2469/10—Detection of antigens from microorganism in sample from host

Definitions

  • the present invention relates to anti-SARS-CoV-2 specific antibodies and uses thereof. More specifically, the present invention relates to recombinant fusions of antibody fragments that are able to bind and neutralize multiple variants of the SARS-CoV-2 spike protein, and uses thereof in treating human SARS-CoV-2 infections.
  • SARS-CoV-2 severe acute respiratory syndrome coronavirus 2
  • COVID-19 coronavirus disease
  • SARS-CoV-1 clade is distinct from the SARS-CoV-2 clade (Starr et al. 2020).
  • VHH-72 Structural analysis of VHH-72 bound to SARS-CoV-1 RBD suggested that VHH-72 is able to cross-react with SARS-CoV-1 and SARS-CoV-2 due to its binding to a relatively conserved epitope on the RBD. This epitope does not, however, appear to overlap with the ACE2 binding site on the RBD. Rather, ACE2 would clash with the framework region of VHH-72, as opposed to classical receptor blocking in which the complementarity determining region (CDR) would occupy the ACE2 binding interface.
  • VHH-72 binds to the SARS-CoV-1 RBD through an H-bonding network involving CDR loops 2 and 3, in which backbone groups participate extensively (Wrapp et al. 2020). Although this network is likely to be conserved in the case of SARS-CoV-2 RBD binding, VHH-72 exhibited faster dissociation kinetics and reduced affinity in this case (Wrapp et al. 2020).
  • the present invention relates to anti-SARS-CoV-2 specific antibodies, and specifically to single domain antibodies, and uses thereof. More specifically, the present invention relates to recombinant fusions of antibody fragments that are able to bind and neutralize multiple variants of the SARS-CoV-2 spike protein, and uses thereof in treating human SARS-CoV-2 infections.
  • the present invention provides an isolated, purified or recombinant antibody or antibody fragment that is specific for the spike protein of a SARS-CoV-2 variant, wherein the antibody or antibody fragment comprises a CDR1 sequence of GRTFSEYAMG (SEQ ID NO:1); a CDR2 sequence of TISWSGGXiTYYTDSVKG (SEQ ID NO:2); and a CDR3 sequence of AGX2GX3VVSEWDYDYDY (SEQ ID NO: 3); wherein: Xi is S or M; X 2 is L or W; and X3 is T or V; including any combinations thereof; with the proviso that when the CDR2 sequence is TISWSGGSTYYTDSVKG (SEQ ID NO:4), then the CDR3 sequence is not AGLGTVVSEWDYDYDY (SEQ ID NO:5), and when the CDR3 sequence is
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention binds the spike protein of a SARS-CoV-2 variant with greater affinity and/or slower dissociation constant than a comparable antibody or antibody fragment comprising a CDR1 sequence of SEQ ID NO:1 , a CDR2 sequence of SEQ ID NO:4, and a CDR3 sequence of SEQ ID NO:5.
  • the isolated, purified or recombinant antibody or antibody fragment comprises: a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO:9; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO:5; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO:7; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO:8; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO:7; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention is specific for a spike protein of a SARS-CoV-2 variant and comprises a sequence selected from the group consisting of: QVQLQESGGGLVQAGGSLRLSCAASGRTFSEYAMGWFRQAPGKEREFVATISWSGGXiTYYT DSVKGRFTISRDNAKNTVYLQMNSLKPDDTAVYYCAAAGX2GX3VVSEWDYDYDYWGQGTQV TVSS (SEQ ID NO: 10), wherein: Xi is S or M; X2 is L or W; and X3 is T or V; including any combinations thereof; with the proviso that when Xi is S, X2 is not L and X3 is not T ; and when X2 is L and X3 is T, Xi is not S.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention comprises an amino acid sequence selected from the group consisting of:
  • VSS (SEQ ID NO: 12); QVQLQESGGGLVQAGGSLRLSCAASGRTFSEYAMGWFRQAPGKEREFVATISWSGGSTYYT DSVKGRFTISRDNAKNTVYLQMNSLKPDDTAVYYCAAAGWGTVVSEWDYDYDYWGQGTQVT VSS (SEQ ID NO: 13);
  • the antibody or antibody fragment comprises an amino acid sequence having at least 65%, at least 70%, at least 75%, least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to the amino acid sequence set forth in SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, or SEQ ID NO: 18.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention is a single-domain antibody (sdAb).
  • the antibody or antibody fragment is in a multivalent display format.
  • the antibody or antibody fragment is linked to an Fc fragment, or comprised within a polypeptide wherein the antibody or antibody fragment is comprised within an Fc fusion.
  • the antibody or antibody fragment is linked to a human Fc fragment from human I gG 1 , I gG2 , lgG3 or lgG4.
  • the antibody or antibody fragment of the present invention is linked to a human Fc fragment from human I gG 1 with the D270G mutation.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention comprises an amino acid sequence selected from the group consisting of:
  • the antibody or antibody fragment comprises an amino acid sequence having at least 65%, at least 70%, at least 75%, least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to the amino acid sequence set forth in SEQ ID NO: 21 , SEQ ID NO: 22, SEQ ID NO: 23, SEQ ID NO: 24, SEQ ID NO: 25, SEQ ID NO: 26, or SEQ ID NO: 27.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention neutralizes a cellular infection mediated by a SARS-CoV-2 variant with an IC50 below the concentration of 100 ng/mL.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention comprises an amino acid sequence selected from the group consisting of SEQ ID NO:25, SEQ ID NO:26, and SEQ ID NO:27 and neutralizes the cellular infection mediated by the SARS-CoV-2 variant more potently than an antibody or antibody fragment comprising SEQ ID NQ:20.
  • the antibody or antibody fragment neutralizes the cellular infection with an IC50 below the concentration of 20 ng/mL.
  • the present invention provides a nucleic acid molecule encoding the isolated, purified or recombinant antibody or antibody fragment of the present invention or encoding a polypeptide fusion as described herein, specifically an Fc fusion comprising any of the antibody or antibody fragments provided herein.
  • the present invention also provides a vector comprising a nucleic acid molecule encoding the isolated, purified or recombinant antibody or antibody fragment of the present invention or a polypeptide fusion as described herein, specifically an antibody Fc fusion.
  • the isolated, purified or recombinant antibody or antibody fragment is immobilized onto a surface.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention may be linked to a cargo molecule, wherein the cargo molecule is a detectable agent, a therapeutic, a drug, a peptide, a carbohydrate moiety, an enzyme, a cytotoxic agent; one or more liposomes loaded with a detectable agent, a therapeutic, a drug, a peptide, an enzyme, or a cytotoxic agent; or one or more nanoparticles, nanowires, nanotubes, or quantum dots.
  • the cargo molecule is a detectable agent, a therapeutic, a drug, a peptide, a carbohydrate moiety, an enzyme, a cytotoxic agent; one or more liposomes loaded with a detectable agent, a therapeutic, a drug, a peptide, an enzyme, or a cytotoxic agent; or one or more nanoparticles, nanowires, nanotubes, or quantum dots.
  • composition comprising one or more than one isolated, purified or recombinant antibody or antibody fragment of the present invention and a pharmaceutically- acceptable carrier, diluent, or excipient.
  • the present invention provides a method of treating a SARS-CoV-2 infection, comprising administering the isolated, purified or recombinant antibody or antibody fragment to a subject in need thereof.
  • a method of capturing the spike protein of a SARS- CoV-2 variant comprising contacting a sample with one or more than one isolated, purified or recombinant antibody or antibody fragment and allowing the spike protein of the SARS-CoV-2 variant to bind to the antibody or antibody fragment.
  • a method of detecting a spike protein of a SARS- CoV-2 variant comprising contacting a sample with one or more than one isolated, purified or recombinant antibody or antibody fragment, allowing the antibody or antibody fragment to bind the spike protein, and detecting the bound antibody or antibody fragment using a suitable detection and/or imaging technology.
  • the isolated, purified or recombinant antibody or antibody fragment is for use to treat a SARS-CoV-2 infection.
  • the present invention provides an isolated, purified or recombinant antibody or antibody fragment that is specific to the spike protein of SARS-CoV-2 and comprises a CDR1 sequence of GRTFSEYAMG (SEQ ID NO:1), a CDR2 sequence of TISWSGGX1TYYTDSVKG (SEQ ID NO:2), and a CDR3 sequence of AGX2GX3WSEWDYDYDY (SEQ ID NO: 3); wherein: Xi is S or M; X 2 is L or W; and X3 is T or V; and combinations thereof; with the proviso that when CDR2 is TISWSGGSTYYTDSVKG (SEQ ID NO:4) then CDR3 is not AGLGTVVSEWDYDYDY (SEQ ID NO: 5), and vice-versa (i.e.
  • the antibody or antibody fragment of the present invention may bind to the spike protein of a SARS-CoV-2 variant with greater affinity and/or a slower dissociation constant than an antibody or antibody fragment comprising a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO:5.
  • the isolated, purified or recombinant antibody or antibody fragment may comprise: a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO: 5; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO: 7; a CDR1 of SEQ ID NO:1 ; a CDR2 of SEQ ID NO:4; and a CDR3 of SEQ ID NO: 8; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO: 7; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO: 8; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention may be selected from the group consisting of: an isolated, purified or recombinant antibody or antibody fragment comprising CDR1 , CDR2 and CDR3 sequences as provided below:
  • the present invention also provides an isolated, purified or recombinant antibody or antibody fragment having an amino acid sequence selected from the group consisting of:
  • DSVKGRFTISRDNAKNTVYLQMNSLKPDDTAVYYCAAAGX2GX3VVSEWDYDYDYWGQGTQV TVSS (SEQ ID NO: 10); wherein: Xi is S or M; X2 is L or W; and X3 is T or V; and combinations thereof; but excluding SEQ ID NO: 11.
  • the present invention provides an isolated, purified or recombinant antibody or antibody fragment having an amino acid sequence selected from the group consisting of: SEQ ID NOS: 12 to 18; or a sequence substantially identical thereto, for example a sequence having at least 99% sequence identity to any of SEQ ID NOS: 12 to 18.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention may be a single-domain antibody (sdAb); the sdAb may be of camelid origin.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention may be in a multivalent display format. Furthermore, an isolated, purified or recombinant antibody or antibody fragment of the present invention may be linked to an Fc fragment, which may from human lgG1 , lgG2, lgG3 or lgG4. In certain non-limiting examples, an isolated, purified or recombinant antibody or antibody fragment of the present invention may be linked to an engineered human IgG 1 Fc fragment, for example carrying the D270G mutation, for attenuating immune effector functions or other mutations for other purposes including mutations that modulate circulating half-life via FcRn recycling.
  • the present invention also provides an isolated, purified or recombinant antibody or antibody fragment having an amino acid sequence selected from the group consisting of SEQ ID NOS: 21 to 27; or any sequence substantially identical thereto.
  • the isolated, purified or recombinant antibodies or antibody fragments provided by the present invention neutralize the cellular infection mediated by a SARS-CoV-2 variant with an IC50 below the concentration of 100 ng/mL.
  • the isolated, purified or recombinant antibody or antibody fragment can have an amino acid sequence selected from the group consisting of SEQ ID NO:25, SEQ ID NO:26, and SEQ ID NO:27, and neutralize the cellular infection caused by a SARS-CoV-2 variant more potently than an antibody or antibody fragment comprising the amino acid sequence of SEQ ID NO:20.
  • the antibody or antibody fragment neutralizes the cellular infection with an IC50 below the concentration of 20 ng/mL.
  • the isolated or purified antibody or antibody fragment of the present invention may be immobilized onto a surface.
  • the isolated, purified, or recombinant antibody or antibody fragment of the present invention may be linked to a cargo molecule; the cargo molecule may be a detectable agent, a therapeutic, a drug, a peptide, a protease, an enzyme, a carbohydrate moiety, or a cytotoxic agent; one or more liposomes loaded with a detectable agent, a therapeutic, a drug, a peptide, an enzyme, or a cytotoxic agent; or one or more nanoparticles, nanowires, nanotubes, or quantum dots.
  • the present invention further encompasses a nucleic acid molecule encoding the isolated, purified, or recombinant antibody or antibody fragment as provided in the present invention.
  • the present invention also includes a vector comprising the nucleic acid molecule encoding an antibody or antibody fragment of the present invention.
  • composition comprising one or more than one isolated, purified, or recombinant antibody or antibody fragment of the present invention and a pharmaceutically- acceptable carrier, diluent, or excipient.
  • the present invention provides engineered agents capable of binding, detecting, capturing, and/or neutralizing SARS-CoV-2. Accordingly, fusion proteins described in this invention and targeting the SARS-CoV-2 spike protein’s receptor binding domain (RBD) may block the SARS-CoV-2 spike protein interaction with the ACE2 receptor on the host cell, thereby preventing virus entry into the host cell; a critical initial step in viral infection and subsequent replication inside the host cell.
  • RBD receptor binding domain
  • the present invention further provides a method of treating a SARS-CoV-2 infection, comprising administering the isolated, purified, or recombinant antibody or antibody fragment of the present invention or the composition described above to a subject in need thereof.
  • a method of capturing a SARS-CoV-2 spike protein comprising contacting a sample with one or more than one isolated, purified, or recombinant antibody or antibody fragment of the present invention immobilized onto a surface, and allowing the SARS-CoV-2 spike protein to bind the antibody or antibody fragment.
  • the method just described may further comprise identifying the captured SARS-CoV-2 spike protein, for example by mass spectrometric methods and/or eluting the SARS-CoV-2 spike protein.
  • the present invention additionally provides a method of detecting a SARS-CoV-2 spike protein, comprising contacting a sample with one or more than one isolated, purified, or recombinant antibody or antibody fragment linked to a cargo molecule, allowing the one or more than one isolated, purified, or recombinant antibody or antibody fragment linked to the cargo molecule to bind the SARS-CoV-2 spike protein, and detecting the bound antibody or antibody fragment using a suitable imaging or detection technology.
  • the cargo molecule may be a detectable agent.
  • FIGURE 1 Amino-acid sequence of VHH-72 with point mutations designed for optimization of SARS-CoV-2 spike protein binding affinity shown in bold. Kabat numbering is shown on top.
  • FIGURES 2A and 2B Characterization of Protein A-purified lead mutants of VHH- 72-Fc by analytical UPLC-SEC (FIG. 2A) and SDS-PAGE staining (FIG. 2B).
  • lane 2 is S56M.L97W (SEQ ID NO: 24)
  • lane 3 is S56M.T99V (SEQ ID NO: 25)
  • lane 4 is L97W.T99V (SEQ ID NO: 26)
  • lane 5 is S56M,L97W,T99V (SEQ ID NO: 27).
  • FIGURES 3A, 3B, 3C, and 3D Biophysical testing of VHH-72-Fc mutant hits.
  • FIG. 3A Dissociation rates (fa) determined by SPR for the three single-mutant hits and resulting multiple mutants, for binding to immobilized spike RBDs from SARS-CoV-1 , SARS-CoV-2 Wuhan, SARS- CoV-2 Beta B.1.351 variant and SARS-CoV-2 Delta B.1.617.2 variant.
  • FIG. 3B Overlaid SPR sensorgrams for the parental variant and the four multiple mutants for binding to immobilized spike RBD from SARS-CoV-2 Wuhan.
  • FIG. 3C Overlaid SPR sensorgrams for the parental variant and the triple mutant for binding to immobilized spike RBD from SARS-CoV-2 B.1.1.529 (Omicron).
  • FIG. 3D Overlaid DSC thermograms for the parental variant and the four multiple mutants.
  • FIGURES 4A and 4B Viral neutralization efficacy by VHH-72-Fc mutant leads.
  • FIG. 4A Neutralization of VLPs expressing the SARS-CoV-2 Wuhan spike protein for infecting HEK293T cells co-expressing human ACE2 and TMPRSS2.
  • FIG. 4B Neutralization of VLPs expressing the SARS-CoV-2 Delta variant B.1.617.2 spike protein for infecting HEK293T cells co-expressing human ACE2 and TMPRSS2.
  • FIGURE 5 Neutralization of live SARS-CoV-2 Wuhan virus for infecting VERO-E6 cells by VHH-72-Fc mutant leads.
  • FIGURES 6A and 6B In vivo therapeutic efficacy of VHH-72-Fc mutant leads in SARS- CoV-2 infected hamsters. Male hamsters were challenged intranasally with 10 4 PFU of SARS- CoV-2 Wuhan isolate. Four hours later they were administered test articles intraperitoneally at a dose of 10 mg/kg.
  • FIG. 6A Body weight changes during the time course of the experiment.
  • FIG. 6B Live virus titers in lung tissues at day 5 post-infection determined with the plaque assay. Data plotted as mean +/- standard error.
  • FIGURES 7A and 7B Structural details of designed VHH-72 mutations.
  • FIG. 7A Structural context of the mutations corresponding to the 3 single-mutant hits (black Ca spheres labeled) of the VHH-72 (black cartoon).
  • Current SARS-CoV-2 mutations of concern are indicated and labeled on the spike RBD (gray surface).
  • the relative position of the ACE2 receptor ectodomain (light-gray Ca trace) bound to the SARS-CoV-2 spike RBD is taken form the PDB entry 6M17.
  • FIG 7B Detailed interactions at the three designed mutation sites.
  • the VHH-72 rendering is in dark-gray cartoon
  • the spike RBD rendering is in light-gray cartoon.
  • the present invention relates to anti-SARS-CoV-2 specific antibodies and uses thereof. More specifically, the present invention relates to recombinant fusions of antibody fragments that bind and neutralize multiple variants of the SARS-CoV-2 spike protein, and uses thereof in treating human SARS-CoV-2 infection.
  • COVID-19 refers to coronavirus disease 2019, a disease caused by the SARS-CoV-2 virus.
  • Symptoms of COVID include respiratory tract infections such as lower respiratory tract infections, high fever, dry cough, shortness of breath, pneumonia; gastro-intestinal symptoms, such as diarrhea; organ failure (kidney failure and renal dysfunction); septic shock and death in severe cases.
  • SARS-CoV-2 refers to severe acute respiratory syndrome virus 2 (SARS-CoV-2), and variants thereof, which was identified as the cause of a serious outbreak starting in Wuhan, China, and which has rapidly spread to other areas of the globe.
  • variant refers to a strain of the SARS-CoV-2 virus having one or more mutations, whether naturally occurring or engineered, relative to another variant of the SARS- CoV-2 virus. For example, a variant may have one or more mutations in the spike protein relative to the spike protein of the originally identified SARS-CoV-2 virus (the Wuhan strain).
  • Non limiting examples of SARS-CoV-2 variants include the alpha (B.1.1.7), beta (B.1.351 , B.1.351.1 ,B.1.351.2, B.1.351.3, B.1.351.4), delta (B.1.617.2, AY.1 , AY.2, AY.3, AY.3.1), gamma (P.1 , P.1.1 , P.1.2), and omicron (B.1.1.529) variants.
  • isolated when used in reference to an antibody or antibody fragment, means that the antibody or antibody fragment has been removed from the genetic environment in which it was generated or expressed.
  • an “isolated” antibody or antibody fragment may be removed from an organism or host cell in which the antibody or antibody fragment was expressed.
  • the term “purified” when used in reference to an antibody or antibody fragment relates to enrichment of the antibody or antibody fragment relative to other components present at the time of antibody production or expression.
  • the antibody or antibody fragment may be enriched relative to cellular components, other proteins, and/or other molecules that were present when the antibody or antibody fragment was generated or expressed. Absolute purity is not required for an antibody or antibody fragment to be considered “purified”. Some impurities may still be present.
  • an antibody or antibody fragment may be considered to be “purified” if it has a purity of 60% or greater.
  • the term “recombinant”, when used in relation to an antibody or antibody fragment, means that the antibody or antibody fragment has been produced by recombinant techniques, wherein generally DNA or RNA encoding the expressed antibody or antibody fragment is inserted into a suitable expression vector that is in turn introduced into a host cell to allow expression of the recombinant antibody or antibody fragment.
  • a recombinant antibody or antibody fragment may include amino acid sequences from two or more sources, such as different proteins or different species.
  • a recombinant antibody or antibody fragment may also include one or more synthetic amino acid sequences.
  • the term “comparable”, when used in reference to an antibody or antibody fragment, means that the antibody or antibody fragment is the same as the reference antibody or antibody fragment, except at the specified amino acid positions. Put another way, the only difference between the “comparable” antibody or antibody fragment and the reference antibody or antibody fragment is the presence of amino acid substitution(s) in the comparable antibody or antibody fragment relative to the reference antibody or antibody fragment, at one or more of the given amino acid positions.
  • the term “about” means plus or minus 0.1 % to 50%, 5% to 50%, 10% to 40%, 10% to 20%, or 10% to 15%, preferably 5% to 10%, most preferably about 5% of the number to which reference is being made.
  • the term “about” may also be used to mean within the error margin for a method or instrument used to collect a measurement, within technical tolerance for manufacturing, or allowing a certain degree of variation around a given value, provided the functionality is still present.
  • the term “about” also allows for rounding to the nearest significant figure.
  • the present inventors optimized VHH-72 by applying ADAPT (Assisted Design of Antibody and Protein Therapeutics), a platform that interleaves structure-based computational predictions with experimental testing in order to optimize the binding affinity of a biologic for its target (Vivcharuk et al. 2017).
  • ADAPT Assisted Design of Antibody and Protein Therapeutics
  • New in this work is the dual-affinity optimization, also known as selectivity optimization, between antibody bonding to multiple targets.
  • ADAPT affinity maturation have led to 10-100-fold binding affinity improvements of several antibody Fab and VH fragments (Vivcharuk et al.
  • ADAPT was also applied for optimizing antibody binding selectivity towards the acidic environment of solid tumors relative to the physiological pH around normal cells (Sulea et al. 2020). ADAPT achieves these levels of affinity and selectivity optimization by significant focusing of the vast mutation space available. Depending on the size of the system, only a few dozen protein variants typically need to be produced, purified and tested. Lead designed mutants of VHH-72 were formatted as fusions with a human lgG1-Fc fragment. These mutants demonstrated improved binding to the SARS-CoV-2 spike protein due to decreased dissociation rates.
  • the terms “variant” and “SARS-CoV-2 variant” refer to a strain of the SARS-CoV-2 virus that has one or more mutations in its spike protein relative to the spike protein of the Wuhan strain of SARS-CoV-2 (GenBank accession no. YP_009724390.1 , as described in Wu et al, 2020).
  • the variant may be, but need not be, a variant of SARS-CoV-2 that has been designated by the World Health Organization as a variant of interest or a variant of concern.
  • the present invention provides engineered single-domain antibodies (VHHS) capable of binding to the SARS-CoV-2 spike protein and neutralizing the virus.
  • VHHS engineered single-domain antibodies
  • fusion proteins described in this invention are capable of targeting the SARS-CoV-2 spike protein’s receptor binding domain (RBD) and consequently blocking the SARS-CoV-2 spike protein interaction with the human ACE2 receptor on the host cell, thereby preventing virus entry into the host cell; a critical initial step in viral infection and subsequent replication inside the host cell.
  • RBD receptor binding domain
  • the term “specific for”, when used in relation to binding by an antibody or antibody fragment, relates to the ability of the antibody or antibody fragment to discriminate between the desired target (e.g. SARS-CoV-2 spike protein) and an unrelated target, such as a host cell protein.
  • An antibody or antibody fragment specific for the spike protein of a SARS-CoV- 2 variant may specifically bind the SARS-CoV-2 spike protein of multiple SARS-CoV-2 variants, including the spike protein of the first-identified (Wuhan) strain of SARS-CoV-2. It may further specifically bind related spike proteins, such as the spike protein of SARS-CoV-1.
  • an antibody or antibody fragment may be considered to be specific for its target if it binds the target with greater affinity than it binds unrelated proteins, allowing the target protein to be detected above background levels of binding. Binding specificity is a relative property and can be determined, for example, using a technique such as surface plasmon resonance (SPR), western blotting, or enzyme-linked immunosorbent assay (ELISA).
  • an antibody or antibody fragment as described herein may be considered to be specific for a spike protein of a SARS-CoV-2 variant if it binds the spike protein with a dissociation constant (KD) or a dissociation rate (fa), that is equal to (i.e. , no statistically significant difference from, using a p- value of 0.05) or lower than that of VHH-72 when assayed under the same, or substantially the same, conditions.
  • KD dissociation constant
  • fa dissociation rate
  • the present invention provides an isolated, purified or recombinant antibody or fragment comprising a CDR1 sequence of GRTFSEYAMG (SEQ ID NO:1); a CDR2 sequence of TISWSGGXiTYYTDSVKG (SEQ ID NO:2); and a CDR3 sequence of AGX2GX3VVSEWDYDYDY (SEQ ID NO: 3); wherein: Xi is S or M; X2 is L or W; and X3 is T or V; and combinations thereof; and with the proviso that when CDR2 is TISWSGGSTYYTDSVKG (SEQ ID NO:4) then CDR3 is not AGLGTVVSEWDYDYDY (SEQ ID NO: 5), and vice-versa (i.e.
  • CDR2 is not TISWSGGSTYYTDSVKG (SEQ ID NO:4) when CDR3 is AGLGTVVSEWDYDYDY (SEQ ID NO: 5); and wherein the antibody or antibody fragment is specific to the spike protein of SARS-CoV- 2.
  • the antibody or antibody fragment of the present invention binds to SARS-CoV-2 spike protein with greater affinity than an antibody or antibody fragment comprising a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO:5.
  • the isolated, purified or recombinant antibody or antibody fragment may comprise: a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO: 9; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO: 5; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO: 7; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:4, and a CDR3 of SEQ ID NO: 8; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID NO: 7; a CDR1 of SEQ ID NO:1 , a CDR2 of SEQ ID NO:6, and a CDR3 of SEQ ID
  • immunoglobulin refers to a protein constructed from paired heavy and light polypeptide chains; various Ig isotypes exist, including IgA, IgD, IgE, IgG, and IgM.
  • VL variable
  • CL constant
  • CH2 constant
  • Fv antigen binding region
  • the light and heavy chain variable regions are responsible for binding the target antigen and can therefore show significant sequence diversity between antibodies.
  • the constant regions show less sequence diversity, and are responsible for binding a number of natural proteins to elicit important biochemical events.
  • the variable region of an antibody contains the antigen binding determinants of the molecule, and thus determines the specificity of an antibody for its target antigen.
  • the majority of sequence variability occurs in six hypervariable regions, three each per variable heavy (VH) and light (VL) chain; the hypervariable regions combine to form the antigen-binding site, and contribute to binding and recognition of an antigenic determinant.
  • the specificity and affinity of an antibody for its antigen is determined by the structure of the hypervariable regions, as well as their size, shape and chemistry of the surface they present to the antigen.
  • Various schemes exist for identification of the regions of hypervariability the two most common being those of Kabat and of Chothia and Lesk.
  • the Kabat definition of the “complementarity-determining regions” (CDR) is based on sequence variability at the antigenbinding regions of the VH and VL domains (Kabat and Wu 1991).
  • the Chothia definition of the “hypervariable loops” (H or L) is based on the location of the structural loop regions in the VH and VL domains (Chothia and Lesk 1987).
  • CDR and hypervariable loop regions that are adjacent or overlapping
  • those of skill in the antibody art often utilize the terms “CDR” and “hypervariable loop” interchangeably, and they may be so used herein.
  • the regions forming the antigen-binding site are presently referred to herein as CDR L1, CDR L2, CDR L3, CDR H1 , CDR H2, CDR H3 in the case of antibodies comprising a VH and a VL domain; or as CDR1 , CDR2, CDR3 in the case of the antigen-binding regions of either a heavy chain or a light chain.
  • the CDR/loops can also be referred to according to the IMGT numbering system (Lefranc et al. 2003), which was developed to facilitate comparison of variable domains. Additionally, a standardized delimitation of the framework regions and of the CDR is provided.
  • an “antibody fragment” as referred to herein may include any suitable antigen-binding antibody fragment known in the art.
  • the antibody fragment may be a naturally-occurring antibody fragment, or may be obtained by manipulation of a naturally-occurring antibody or by using recombinant methods.
  • an antibody fragment may include, but is not limited to a Fv, single-chain Fv (scFv; a molecule consisting of VL and H connected with a peptide linker), Fab, F(ab’)2, single domain antibody (sdAb; a fragment composed of a single VL or VH), and multivalent presentations of any of these.
  • the antibody fragment may be an sdAb derived from a naturally-occurring source.
  • Heavy chain antibodies of camelid origin (Hamers-Casterman et al. 1993) lack light chains and thus their antigen binding sites consist of one domain, termed VHH.
  • sdAbs have also been observed in shark and are termed VNAR (Nuttall et al. 2003).
  • Other sdAbs may be engineered based on human Ig heavy and light chain sequences (Jespers et al. 2004).
  • sdAb includes those sdAbs directly isolated from VH, VHH, VL, or VNAR reservoir of any origin through phage display or other technologies, sdAbs derived from the aforementioned sdAbs, recombinantly produced sdAbs, as well as those sdAbs generated through further modification of such sdAbs by humanization, affinity maturation, stabilization, solubilization, e.g., camelization, or other methods of antibody engineering. Also encompassed by the present invention are sdAb homologues, derivatives, or fragments that retain the antigenbinding function and specificity of the sdAb.
  • An sdAb comprises a single immunoglobulin domain that retains the immunoglobulin fold; most notably, only three CDR/hypervariable loops form the antigen-binding site.
  • not all CDR may be required for binding the antigen.
  • one, two, or three of the CDRs may contribute to binding and recognition of the antigen by the sdAb of the present invention.
  • CDR1 , CDR2, and CDR3 The CDRs of the sdAb or variable domain are referred to herein as CDR1 , CDR2, and CDR3, and delineated according to the Kabat definition for CDR2 and CDR3, and by the union of Kabat and Chothia definitions for CDR1 (Chothia and Lesk 1987; Kabat and Wu 1991). Also, the Kabat numbering system is used throughout (FIG. 1).
  • an antibody or antibody fragment of the invention may be an sdAb.
  • the sdAb may be of camelid origin or derived from a camelid VHH, and thus may be based on camelid framework regions; alternatively, the CDR described above may be grafted onto VNAR, VHH, H or L framework regions.
  • the hypervariable loops described above may be grafted onto the framework regions of other types of antibody fragments (Fv, scFv, Fab).
  • the present embodiment further encompasses an antibody fragment that is “humanized” using any suitable method known in the art including, for example but not limited to, CDR grafting and veneering.
  • Humanization of an antibody or antibody fragment comprises replacing one or more amino acids in the sequence with its/their human counterpart(s), as found in the human consensus sequence, without loss of antigen-binding ability or specificity; this approach reduces immunogenicity of the antibody or antibody fragment when introduced into human subjects.
  • one or more than one heavy chain CDR as defined herein may be fused or grafted to a human variable region ( H, or VL), or to other human antibody fragment framework regions (Fv, scFv, Fab).
  • H, or VL human variable region
  • Fv, scFv, Fab human antibody fragment framework regions
  • the conformation of said one or more than one hypervariable loop is preserved, and the affinity and specificity of the sdAb for its target (i.e., SARS-CoV-2 spike protein) is also preserved.
  • CDR grafting is known in the art and is described in at least the following: US Patent No. 6180370, US Patent No. 5693761 , US Patent No. 6054297, US Patent No. 5859205, and European Patent No. 626390.
  • Veneering also referred to in the art as “variable region resurfacing”, involves humanizing solvent-exposed positions of the antibody or antibody fragment; thus, buried non-humanized residues, which may be important for CDR conformation, are preserved while the potential for immunological reaction against solvent- exposed regions is minimized.
  • Veneering is known in the art and is described in at least the following: US Patent No. 5869619, US Patent No. 5766886, US Patent No. 5821123, and European Patent No. 519596. Persons of skill in the art would also be amply familiar with methods of preparing such humanized antibody fragments and humanizing amino acid positions.
  • the antibody or antibody fragment provided herein is a pan-specific anti-SARS-CoV-2 antibody capable of binding the spike protein of a plurality of SARS-CoV-2 variants and may comprise an amino acid sequence selected from the group consisting of:
  • the present invention accordingly provides an isolated, purified or recombinant antibody or antibody fragment having an amino acid sequence selected from the group consisting of:
  • a sequence substantially identical thereto may have at least 65%, at least 70%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to the reference sequence, or have any percent identity or fractional percent sequence identity between 65% and 100% (e.g., 84%, 67.7% or 96.85%) to the reference sequence.
  • a substantially identical sequence may comprise one or more conservative amino acid mutations relative to the reference sequence.
  • a conservative amino acid mutation may include addition, deletion, or substitution of an amino acid; a conservative amino acid substitution is defined herein as the substitution of an amino acid residue for another amino acid residue with similar chemical properties (e.g. size, charge, or polarity).
  • a conservative mutation may be an amino acid substitution.
  • Such a conservative amino acid substitution may substitute a basic, neutral, hydrophobic, or acidic amino acid for another of the same group.
  • basic amino acid it is meant hydrophilic amino acids having a side chain pKa value of greater than 7, which are typically positively charged at physiological pH.
  • Basic amino acids include arginine (Arg or R) and lysine (Lys or K).
  • neutral amino acid also “polar amino acid”
  • Polar amino acids include serine (Ser or S), threonine (Thr or T), cysteine (Cys or C), tyrosine (Tyr or Y), asparagine (Asn or N), glutamine (Gin or Q) and histidine (His or H).
  • hydrophobic amino acid also “non-polar amino acid” is meant to include amino acids exhibiting a hydrophobicity of greater than zero according to the normalized consensus hydrophobicity scale (Eisenberg et al. 1984).
  • Hydrophobic amino acids include proline (Pro or P), isoleucine (lie or I), phenylalanine (Phe or F), valine (Vai or V), leucine (Leu or L), tryptophan (Trp or W), methionine (Met or M), alanine (Ala or A), and glycine (Gly or G).
  • “Acidic amino acid” refers to hydrophilic amino acids having a side chain pKa value of less than 7, which are typically negatively charged at physiological pH. Acidic amino acids include glutamate (Glu or E), and aspartate (Asp or D).
  • Sequence identity is used to evaluate the similarity of two sequences; it is determined by calculating the percent of residues that are the same when the two sequences are aligned for maximum correspondence between residue positions. Any known method may be used to calculate sequence identity; for example, computer software is available to calculate sequence identity. Without wishing to be limiting, sequence identity can be calculated by software such as NCBI BLAST2 service maintained by the Swiss Institute of Bioinformatics (and as found at http://ca.expasy.org/tools/blast/), BLAST-P, Blast-N, or FASTA-N, or any other appropriate software that is known in the art.
  • the substantially identical sequences of the present invention may have at least 65% sequence identity to the reference sequence; in another example, the substantially identical sequences may have at least 65%, at least 70%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity, or any percentage or fractional percentage therebetween, at the amino acid level or at the nucleotide sequence level to one or more sequences described herein.
  • the substantially identical sequence retains the activity and specificity of the reference sequence.
  • the difference in sequence identity at the amino acid level may be due to conservative amino acid mutation(s).
  • the present invention may be directed to an antibody or antibody fragment comprising a sequence having at least 98% or at least 99% sequence identity to that of a VHH described herein.
  • An isolated, purified or recombinant antibody or antibody fragment of the present invention may bind to a conformational or linear epitope.
  • a conformational epitope is formed by amino acid residues that are discontinuous in sequence, but proximal in the three-dimensional structure of the antigen.
  • a linear epitope also referred to in the art as a “sequential epitope” is recognized by its linear amino acid sequence, or primary structure.
  • the conformational and linear epitopes of the antibodies or antibody fragments of the present invention recognize conformational and linear epitopes located in the region of TcdA responsible for cell-receptor binding.
  • the antibody or antibody fragment of the present invention may also comprise one or more additional sequences to aid in expression, detection or purification of a recombinant antibody or antibody fragment. Any such sequences or tags known to those of skill in the art may be used.
  • the antibody or antibody fragment may comprise a targeting or signal sequence (for example, but not limited to ompA), a detection/purification tag (for example, but not limited to c-Myc or a Hiss or Hise), or a combination of any two or more thereof.
  • the one or more additional sequences may comprise a biotin recognition site such as that described by Cronan et al in WO 95/04069 or Voges et al in WO/2004/076670.
  • one or more linker sequences may be used in conjunction with the one or more additional sequences or tags, or may serve as a detection/purification tags.
  • the antibody or antibody fragment of the present invention may also be in a multivalent display format, also referred to herein as multivalent presentation.
  • Multimerization may be achieved by any suitable method known in the art. For example, and without wishing to be limiting in any manner, multimerization may be achieved using self-assembly molecules as described in Zhang, Li, et al. 2004; Zhang, Tanha, et al. 2004; and W02003/046560.
  • the described method produces pentabodies by expressing a fusion protein comprising the antibody or antibody fragment of the present invention and the pentamerization domain of the B-subunit of an AB5 toxin family (Merritt and Hol 1995); the pentamerization domain assembles into a pentamer, through which a multivalent display of the antibody or antibody fragment is formed.
  • Each subunit of the pentamer may be the same or different, and may have the same or different specificity.
  • the pentamerization domain may be linked to the antibody or antibody fragment using a linker; such a linker should be of sufficient length and appropriate composition to provide flexible attachment of the two molecules, but should not hamper the antigen-binding properties of the antibody.
  • the antibody or antibody fragment may be presented as a dimer, a trimer, or any other suitable oligomer. This may be achieved by methods known in the art, for example direct linking connection, c-jun/Fos interaction (de Kruif and Logtenberg 1996) or “knobs-into-holes” interaction (Ridgway, Presta, and Carter 1996).
  • Another method known in the art for multimerization is to dimerize the antibody or antibody fragment using an Fc domain, e.g., human Fc domains.
  • the Fc domains may be selected from various classes including, but not limited to, IgG, IgM, or various subclasses including, but not limited to lgG1 , lgG2, etc.
  • the Fc gene in inserted into a vector along with the sdAb gene to generate a sdAb-Fc fusion protein (Bell et al. 2010; Iqbal et al. 2010); the fusion protein is recombinantly expressed then purified.
  • multivalent display formats may encompass chimeric formats of VHHS linked to an Fc domain, or bi- or tri-specific antibody fusions with two or three VHHS recognizing unique epitopes.
  • Enhanced viral neutralizing efficacy may also be obtained using various techniques, including PEGylation, fusion to serum albumin, or fusion to serum albumin-specific antibody fragments; these approaches increase their blood circulation half-lives, size and avidity.
  • Certain non-limiting embodiments of the present invention may incorporate a human lgG1-Fc fragment including a one-residue (alanine) linker, followed by the P226-P243 hinge region and the A244-G477 CH2 and CH3 domains (Kabat numbering was used throughout).
  • the C233 in the hinge region normally used to link to the light chain of a conventional human lgG1 antibody, can be optionally mutated to serine in order to prevent formation of undesired covalent disulfide-bonded adducts.
  • We introduced a D270G mutation in the CH2 domain in order to attenuate immune receptor functions by reducing binding to human Fey receptors (Shields et al. 2001).
  • Attenuation rather than complete abrogation of immune receptor functions, would reduce antibody-dependent enhancement (ADE) (Bournazos, Gupta, and Ravetch 2020), as well as reduce the risk exacerbating the hyperinflammatory response often associated with severe COVID-19 development (Manson et al. 2020) while still benefitting from the natural pathogen clearance mechanism of macrophages.
  • AD antibody-dependent enhancement
  • the present invention provides fusion proteins, specifically Fc fusion proteins, comprising an isolated, purified or recombinant antibody or antibody fragment of the present invention, wherein the fusion protein provided may comprise an amino acid sequence selected from the group consisting of:
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention possesses the ability to neutralize a cellular infection by a SARS-CoV-2 variant. Preferably, this inhibition of infection is achieved at low concentrations which preferably correspond to IC50 values below 100 ng/mL.
  • the isolated, purified or recombinant antibody or antibody fragment may have an amino acid sequence selected from the group consisting of SEQ ID NO:25, SEQ ID NO:26, and SEQ ID NO:27 and neutralizes the cellular infection caused by SARS-CoV-2 more potently than an antibody or antibody fragment comprising SEQ ID NQ:20, and preferably with an IC50 below the concentration of 20 ng/mL.
  • the isolated, purified or recombinant antibody or antibody fragment of the present invention is advantageously pan-specific, that is to say capable of neutralizing multiple variants of the SARS-CoV-2, for example, and not limited to, Wuhan, Beta (B.1.351), Delta (B.1.617.2) and Omicron (B.1.1.529) virus variants.
  • This broad-spectrum neutralization is achievable due to a similarly broad-spectrum capacity of the antibody or antibody fragment of the present invention to bind to the spike protein of various SARS-CoV-2 variants.
  • the present invention also encompasses nucleic acid sequences encoding the molecules as described herein.
  • the nucleic acid sequence may be codon-optimized for expression in various micro-organisms or host cells.
  • the present invention also encompasses vectors comprising the nucleic acids as just described.
  • the invention encompasses cells comprising the nucleic acid and/or vector as described.
  • the present invention further encompasses the isolated, purified or recombinant antibody or antibody fragment immobilized onto a surface using various methodologies; for example, and without wishing to be limiting, the antibody or antibody fragment may be linked or coupled to the surface via His-tag coupling, biotin binding, covalent binding, adsorption, and the like.
  • Immobilization of the antibody or antibody fragment of the present invention may be useful in various applications for capturing, purifying or isolating proteins.
  • the solid surface may be any suitable surface, for example, but not limited to the well surface of a microtiter plate, channels of surface plasmon resonance (SPR) sensorchips, membranes, beads (such as magnetic-based or sepharose-based beads or other chromatography resin), glass, plastic, stainless steel, a film, or any other useful surface such as nanoparticles, nanowires and cantilever surfaces.
  • SPR surface plasmon resonance
  • the present invention also provides a method of capturing and detecting the presence of the spike protein of a SARS-CoV-2 variant, comprising contacting a sample (such as, but not limited to SARS-CoV-2 infected human/animal organ or tissue sample fluid, or any other suitable sample) with one or more than one isolated, purified or recombinant antibody or antibody fragment of the present invention.
  • a sample such as, but not limited to SARS-CoV-2 infected human/animal organ or tissue sample fluid, or any other suitable sample
  • the isolated, purified or recombinant antibody or antibody fragment may be immobilized onto a surface.
  • the SARS-CoV-2 spike protein then binds to the isolated, purified, or recombinant antibody or antibody fragment and is thus captured.
  • the SARS-CoV-2 spike protein may then optionally be identified by mass spectrometric methods and/or released or eluted from its interaction with the antibody or antibody fragment.
  • Methods for releasing or eluting bound molecules are well-known to those of skill in the art (for example but not limited to heat elution steps), as are spectrometric methods capable of detecting and identifying the SARS-CoV-2 spike protein.
  • the isolated, purified, or recombinant antibody or antibody fragment of the present invention allows for the use of particularly robust affinity purification reagents due to its resistance to acidic and heat elution steps.
  • the invention also encompasses the antibody or antibody fragment as described above linked to a cargo molecule.
  • the cargo molecule may be a detectable agent, a therapeutic agent, a drug, a peptide, an enzyme, a protease, a carbohydrate moiety, a cytotoxic agent, one or more liposomes loaded with any of the previously recited types of cargo molecules, or one or more nanoparticles, nanowires, nanotubes, or quantum dots or any suitable molecule or any biological or chemical moiety.
  • the cargo molecule may be a protease that may digest the SARS-CoV-2 spike protein; in a further nonlimiting example, the protease may be linked to a VHH such as a mutant VHH that is protease resistant.
  • the cargo molecule may be a cytotoxic agent that may be antiviral or toxic towards host cells “infected” with SARS-CoV-2.
  • the cargo molecule is a liposome, which makes the construct well-suited as a delivery agent for mucosal vaccines.
  • the cargo molecule may be linked to the antibody or antibody fragment by any suitable method known in the art.
  • the cargo molecule may be linked to the peptide by a covalent bond or ionic interaction.
  • the linkage may be achieved through a chemical cross-linking reaction, or through fusion using recombinant DNA methodology combined with any peptide expression system, such as bacteria, yeast or mammalian cell-based systems.
  • Methods for linking an antibody or antibody fragment to a therapeutic agent or detectable agent would be well-known to a person of skill in the art.
  • the present invention also encompasses an antibody or antibody fragment linked to a detectable agent.
  • the SARS-CoV-2 spike protein-specific antibody or antibody fragment may be linked to a radioisotope, a paramagnetic label, a fluorophore, an affinity label (for example biotin, avidin, etc), fused to a detectable protein-based molecule, nucleotide, quantum dot, nanoparticle, nanowire, or nanotube or any other suitable agent that may be detected by imaging methods.
  • the antibody or antibody fragment may be linked to a fluorescent agent such as FITC or may genetically be fused to the Enhanced Green Fluorescent Protein (EGFP).
  • the antibody or antibody fragment may be linked to the detectable agent using any method known in the art (recombinant technology, chemical conjugation, etc.).
  • the present invention further provides a method of detecting a SARS-CoV-2 spike protein, comprising contacting a sample (such as, but not limited to a SARS-CoV-2 infected human/animal organ or tissue, sample fluid, or any other suitable sample) with one or more than one isolated, purified or recombinant antibody or antibody fragment of the present invention.
  • a sample such as, but not limited to a SARS-CoV-2 infected human/animal organ or tissue, sample fluid, or any other suitable sample
  • the isolated, purified or recombinant antibody or antibody fragment may be linked to a detectable agent.
  • the SARS-CoV-2 spike protein can then be detected using detection and/or imaging technologies known in the art, such as, but not limited to mass spectrometric or immunoassay methods.
  • the isolated, purified or recombinant antibody or antibody fragment linked to a detectable agent may be used in immunoassays (IA) including, but not limited to enzyme IA (EIA), ELISA, “rapid antigen capture”, “rapid chromatographic IA”, and “rapid EIA”.
  • IA immunoassays
  • the present invention also encompasses a composition comprising one or more than one isolated, purified or recombinant antibody or antibody fragment as described herein.
  • the composition may comprise a single antibody or antibody fragment as described above, or it may comprise a mixture of antibodies or antibody fragments.
  • the composition may also comprise a pharmaceutically acceptable diluent, excipient, or carrier.
  • the diluent, excipient, or carrier may be any suitable diluent, excipient, or carrier known in the art, and must be compatible with other ingredients in the composition, be compatible with the method of delivery of the composition, and not be deleterious to the recipient of the composition.
  • the composition may be in any suitable form; for example, the composition may be provided in suspension form, powder form (for example, but limited to lyophilised or encapsulated), capsule or tablet form.
  • the carrier may comprise water, saline, a suitable buffer, or additives to improve solubility and/or stability; reconstitution to produce the suspension is effected in a buffer at a suitable pH to ensure the viability of the antibody or antibody fragment.
  • Dry powders may also include additives to improve stability and/or carriers to increase bulk/volume; for example, and without wishing to be limiting, the dry powder composition may comprise sucrose or trehalose.
  • the composition may be so formulated as to deliver the antibody or antibody fragment to the gastrointestinal tract of the subject.
  • the composition may comprise encapsulation, time-release, or other suitable technologies for delivery of the antibody or antibody fragment. It would be within the competency of a person of skill in the art to prepare suitable compositions comprising the present compounds.
  • the present invention also comprises a method of treating a SARS-CoV-2 infection, comprising administering the isolated, purified or recombinant antibody or antibody fragment of the present invention, or a composition comprising the antibody or antibody fragment, to a subject in need thereof.
  • Any suitable method of delivery may be used.
  • the antibody or antibody fragment, or the composition may be delivered systemically (orally, nasally, intravenously, intraperitoneally, intramuscularly, etc.) or may be delivered to the gastrointestinal tract. Those of skill in the art would be familiar with such methods of delivery.
  • the 2.2-A crystal structure of the VHH-72 sdAb bound to the RBD of the SARS-CoV-1 spike protein was downloaded from the Protein Data Bank (PDB ID: 6WAQ) (Wrapp et al. 2020), and was used as template to building a homology model of the VHH-72 sdAb bound to the RBD of the SARS-CoV-2 spike protein (Wuhan sequence). Both complexes were refined by constrained energy minimization using the AMBER force field (Hornak et al. 2006; Cornell et al. 1995), with a distance-dependent dielectric and an infinite distance cutoff for non-bonded interactions.
  • Non-hydrogen atoms were restrained at their crystallographic positions with harmonic force constants of 40 and 10 kcal/(mol A 2 ) for the backbone and side-chain atoms, respectively, except for the amino-acid residues mutated in the SARS-CoV-2 homology model that were allowed to move freely. Resulting structures of the two complexes were used as starting points for tandem affinity maturation of the VHH-72. The ADAPT platform was then used for affinity maturation by single-point scanning mutagenesis simulations carried out at several positions within the CDR loops of VHH-72, as described previously for other systems (Vivcharuk et al. 2017; Sulea et al. 2018).
  • Scoring of binding affinity was mainly based on the average Z-score and also on the average rank score over the scores calculated with the three component energy functions, SIE (Naim et al. 2007; Sulea and Purisima 2012), FoldX-FOLDEF (Guerois, Nielsen, and Serrano 2002), and Rosetta- Interface (O Conchuir et al. 2015). Further technical and implementation details of this consensus approach and its component methods can be found in Sulea et al (Sulea et al. 2016). Prior to binding affinity predictions, the FoldX-FOLDEF energy function (Guerois, Nielsen, and Serrano 2002) was used to estimate the effect of substitutions on the internal stability of the VHH structure.
  • mutations predicted to be destabilizing by introducing folding free energy changes larger than 2.71 kcal/mol (i.e. , 100-fold increase of unfolding equilibrium constant) relative to the parental molecule were discarded from further evaluation.
  • Selection of designed mutants for experimental testing took into account the consensus Z-scores obtained in both complexes undergoing optimization.
  • Preferred criteria for selecting a particular mutation required an improvement in binding to SARS-CoV-2 RBD with a consensus Z-score below -1 together with an improvement in binding to SARS-CoV-1 RBD with a consensus Z-score below 0.
  • 476 single-point mutations to all natural amino acids except Cys and Pro were computationally evaluated in the CDRs of VHH-72.
  • the scanned region covered 28 positions (S30-E31 from CDR1 , S52-K64 from CDR2, and G96-D100g from CDR3) that when substituted have the potential to alter the antigen-binding affinity.
  • a second selection step was then applied to retain some of the best scoring mutations at each position, in addition to reducing redundancy in the physico-chemical nature of the mutation for cases where multiple mutants were proposed at a given position.
  • Visual inspection of structural model was involved to prune mutations with apparent poor steric and electrostatic complementarity, as in the case of mutations at position T57, and selection of the lower scoring mutation at position T99.
  • the final list proposed for experimental testing in the first round included a 13 single mutations at 8 positions, which were well balanced between CDR loops 2 (6 mutations at 4 positions) and 3 (7 mutations at 4 positions). This is a desired attribute in the set of single mutants that will increase the likelihood of additive contributions of mutation effects in the subsequent round of combining successful mutations.
  • Transfected DNA consisted of a 8.5:1 .0:0.5 ratio of VHH-72-Fc, Bcl-XL (anti-apoptotic) and GFP (transfection marker) expression vectors, respectively.
  • DNA PEI polyplexes
  • cell cultures were incubated for 24 h on an orbital shaking platform at an agitation rate of 120 rpm at 37°C in a humidified 5% CO2 atmosphere. Cultures were then fed with Feed 4 (Fujifilm Irvine Scientific, Santa Ana CA) at 2.5% v/v and anti-clumping supplement (Fujifilm Irvine Scientific) at 1 :500, and transferred to 32°C.
  • Cell cultures were harvested by centrifugation at 20 minutes at 4,000 rpm and supernatants were then filtered using 0.2 urn StericupTM or SteriflipTM vacuum filtration units (MilliporeSigma, Burlington MA). Purifications from cell-culture supernatants were performed by protein-A affinity chromatography, using 1-, 5- or 10-mL MabSelectTM SuReTM columns (Cytiva Life Sciences) depending on production scale. Columns were equilibrated in HyCloneTM Dulbecco's phosphate-buffered saline (DPBS; Cytiva Life Sciences). Supernatants were loaded at a residence time > 3 min.
  • DPBS HyCloneTM Dulbecco's phosphate-buffered saline
  • Variants used for in vivo studies were concentrated at approximately 1.3 mg/mL or 6.7 mg/mL by ultrafiltration using Vivaspin® Turbo turbo centrifugal concentrator with a membrane molecular weight cut off of 10 kDa (Sartorius) at room temperature following the manufacturer’s instructions.
  • the protein concentration was monitored on a NanoDropTM 2000 spectrophotometer (ThermoFisher Scientific) using absorbance at 280 nm and the calculated specific extinction coefficient of each variant. All the formulated samples for in vivo studies have an estimated homodimer percentage higher than 98.5% and endotoxin levels below 0.1 EU/mg.
  • the lead mutants had excellent developability profiles, including: (1) production yields by transient transfection at 25-mL scale in CHO cells ranging between 350-500 mg/L with cell viabilities over 91 % at day 7 post transfection; and (2) single-step purification by Protein-A affinity chromatography that afforded >99% pure material (by analytical UPLC-SEC and SDS-PAGE/CoomassieTM staining, FIG. 2).
  • VHH-72-Fc variants were analyzed for binding to the spike-RBD domains of SARS-CoV-1, SARS-CoV-2 Wuhan, SARS-CoV-2 B.1.351 , SARS-CoV-2 B.1.617.2 and SARS- CoV-2 B.1.1.529 using a BiacoreTM T200 surface plasmon resonance (SPR) instrument (Cytiva, Marlborough, MA). Production and purification of these RBDs were carried out as described elsewhere (Colwill et al. 2021). The S-RBD of SARS-CoV-2 B.1.1.529 residues R319-N542 was produced and purified following the same protocols.
  • SPR surface plasmon resonance
  • Samples were assayed at 25°C using PBS containing 0.05% Tween® 20 (Teknova, Hollister, CA) with added 3.4 mM ethylenediaminetetraacetic acid (EDTA) and 0.05% Tween 20 as running buffer.
  • Spike-RBD samples from SARS-CoV2 (Wuhan and B.1.351 variants) and SARS-CoV-1 were diluted to 10 pg/mL in 10 mM NaOAc immobilization buffer pH 4.5 (Cytiva, Marlborough, MA) and immobilized to approximately 350 Rlls using the Immobilization Wizard for NHS/EDC amine coupling within the BiaControl software.
  • the spike-RBD interactions were assessed using single cycle kinetics analysis for each variant with three concentrations using a 10-fold dilution from the top concentration of 100 nM.
  • the VHH-72-Fc samples were injected at 50 pL/min with a contact time of 60 s and a 600-s dissociation.
  • Sensorgrams were double referenced to the mock-activated blank sensor surface and analyzed for kinetic determination using a 1 :1 binding model in BiaEvaluation software v3.1 (GE Healthcare). All VHH-72-Fc variants were run in triplicate. Due to avidity effects from the bivalent nature of the VHH-72-Fc variants, only dissociation rates ( d ) are reported.
  • the best variant was the triple mutant S56M,L97W,T99V with ka improved over 30-fold for the Wuhan CoV-2 spike RBD, over 70-fold for Beta B.1.351 CoV-2 spike RBD and over 20-fold for Delta B.1.617.2 CoV-2 spike RBD relative to the parent.
  • These dissociation rates which are in the single-digit 10' 4 s -1 range, approached that measured against the CoV-1 spike RBD which was maintained between the triple mutant and the parent.
  • the double mutant L97W.T99V closely followed the triple mutant with a similar binding strength against the two CoV-2 virus variants, while also affording a 4-fold improved d from the CoV-1 relative to the parent.
  • DSC Differential scanning calorimetry
  • Pseudotyped SARS-CoV2 spike lentiviral particles were produced using either the pHDM-SARS-CoV-2 Wuhan-Hu-1 expressing the SARS-CoV-2 Wuhan-Hu-1 spike protein (GenBank # NC_045512) or pcDNA3.3-SARS2-B.1 .617.2 expressing the SARS-CoV-2 B.1 .617.2 (Delta variant) spike protein, a gift from David Nemazee (Addgene plasmid # 172320) under a CMV promoter and packaged into lentiviral vectors obtained through BEI Resources, NIAID, NIH: SARS-Related Coronavirus 2, Wuhan-Hu-1 Spike-Pseudotyped Lentiviral Kit, NR-52948 and according to the protocols and reagents described by the Bloom lab (Crawford et al.
  • HEK293SF-3F6 cells (Cote et al. 1998) were used for large-scale production of lentiviral particles in 300 mL; (2) post-transfection HEK293SF-3F6 cells were incubated at 33°C for improved yield; (3) 72 h post-infection lentiviral particles were harvested and subjected to concentration by sucrose cushion centrifugation. Briefly, the supernatant was placed on 20% sucrose cushion and spun for 3 h at 37,000xg at 4°C. The pellet containing the concentrated pseudo typed VLP was then resuspended in DMEM with 10% FBS and aliquoted.
  • HEK293T cells overexpressing human ACE2 and TMPRSS2 obtained from BEI Resources repository of ATCC and the NIH (NR-55293).
  • Pseudovirus neutralization assay was performed according to the previously described protocol (Crawford et al. 2020) and was adapted for 384-well plate. Briefly, 3-fold serial dilutions of the VHH-72-Fc samples were incubated with diluted virus at a 1 :1 ratio for 1 h at 37°C before addition to HEK293- ACE2/TMPRSS2 cells. Infectivity was then measured by luminescence readout per well.
  • VLP pseudo typed virus like particle
  • the first set of experiments employed a non-replicating pseudovirus neutralization assay (Crawford et al. 2020). In this assay, two different VLPs were produced and tested, containing SARS-CoV-2 spike protein from either the Wuhan or Delta B.1.617.2 strains packaged, a luciferase reporter and the minimal set of lentiviral proteins required to assemble the VLPs. A monolayer of HEK293T cells co-expressing human ACE2 and human TMPRSS2 were exposed to the VLPs.
  • the ability to block entry of these particles into cells was detected by loss of signal of the luciferase reporter.
  • the advantageous and unexpected benefits of the antibodies provided in the present invention as shown in FIG. 4AB and listed in Table 3, the three multiple mutants of VHH-72-Fc blocked cellular infection against the two VLPs more potently than the parental compound.
  • the best neutralization potencies were obtained with the triple mutant S56M,L97W,T99V, which displayed IC50 values of 9 ng/mL and 4 ng/mL against Wuhan and Delta B.1.617.2 spike protein pseudotyped VLPs, respectively, which represent 11-fold and 18- fold improvements, respectively, relative to the parent compound.
  • the double mutant L97W.T99V also showed strong neutralization potencies, amounting to 6-fold and 4-fold improvements, respectively, relative to the parental compound.
  • Example 6 In vivo hamster infection model
  • VHH-72 interacts with the 17-amino-acid contiguous sequence region 368-LYNSASFSTFKCYGVSP-384 (SEQ ID NO: 32) of the SARS-CoV-2 spike protein RBD. These positions are far away from mutations present in currently-circulating SARS- CoV-2 variants of concern (FIG. 7A), suggesting cross-reactivity with these variants. As virus mutations tend to occur at the interface with the ACE2 host receptor, which is distinct from the VHH-72 binding interface (FIG. 7A), it is likely that mutating any of these three positions of VHH- 72 alone or in combination would also retain binding to emerging virus variants in the future.
  • the S56M mutation (from the CDR2 loop) introduces new hydrophobic contacts with the side-chains of F374 and F377.
  • this hydrophobic mutation is also on close proximity of polar backbone atoms of other residues in the region L367-F374, and eliminates an H-bond anchor to the backbone carbonyl of N370. Since all three mutations interact with a contiguous linear epitope and two of the mutations are adjacent within the CDR3 loop, we expected a less-than-optimal additivity of single mutation effects upon combining them into multiple-point mutants, as it was in fact observed experimental (see next section, vide infra).

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Virology (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Medicinal Chemistry (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Oncology (AREA)
  • Biophysics (AREA)
  • Biochemistry (AREA)
  • Immunology (AREA)
  • Pulmonology (AREA)
  • Communicable Diseases (AREA)
  • Genetics & Genomics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Peptides Or Proteins (AREA)

Abstract

La présente invention concerne des anticorps spécifiques de la protéine Spike du SARS-CoV-2 et des fragments d'anticorps, des compositions comprenant les anticorps ou les fragments d'anticorps, et leurs utilisations. Les anticorps anti-protéine anti-Spike et les fragments d'anticorps peuvent être spécifiques du SARS-CoV-2 comprenant des variants de virus courants et émergents. L'invention concerne également des procédés de traitement d'une infection par le SARS-CoV-2, des procédés de capture de protéines Spike du SARS-CoV-2, et des procédés de détection de protéines Spike du SARS-CoV-2 à l'aide des anticorps ou des fragments d'anticorps.
PCT/IB2022/062007 2021-12-17 2022-12-09 Anticorps sars-cov-2 pan-spécifiques et leurs utilisations WO2023111796A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US202163290701P 2021-12-17 2021-12-17
US63/290,701 2021-12-17
US202263318687P 2022-03-10 2022-03-10
US63/318,687 2022-03-10

Publications (1)

Publication Number Publication Date
WO2023111796A1 true WO2023111796A1 (fr) 2023-06-22

Family

ID=86773701

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2022/062007 WO2023111796A1 (fr) 2021-12-17 2022-12-09 Anticorps sars-cov-2 pan-spécifiques et leurs utilisations

Country Status (1)

Country Link
WO (1) WO2023111796A1 (fr)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021156490A2 (fr) * 2020-02-06 2021-08-12 Vib Vzw Liants du coronavirus
WO2022238550A1 (fr) * 2021-05-12 2022-11-17 Vib Vzw Liants de coronavirus pan-spécifiques

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021156490A2 (fr) * 2020-02-06 2021-08-12 Vib Vzw Liants du coronavirus
WO2022238550A1 (fr) * 2021-05-12 2022-11-17 Vib Vzw Liants de coronavirus pan-spécifiques

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DANIEL WRAPP, DE VLIEGER DORIEN, CORBETT KIZZMEKIA S., TORRES GRETEL M., WANG NIANSHUANG, VAN BREEDAM WANDER, ROOSE KENNY, VAN SCH: "Structural Basis for Potent Neutralization of Betacoronaviruses by Single-Domain Camelid Antibodies", CELL, vol. 181, no. 5, 28 May 2020 (2020-05-28), Amsterdam NL , pages 1004 - 1015.e15, XP055764639, ISSN: 0092-8674, DOI: 10.1016/j.cell.2020.04.031 *

Similar Documents

Publication Publication Date Title
CN111718411B (zh) 一种抗SARS-CoV-2的单克隆抗体1F2
JP4992068B2 (ja) 超高親和性中和抗体
TWI700295B (zh) 對會感染人類之腸病毒具有專一性之抗體
JP6050747B2 (ja) インフルエンザ受動免疫化に有用な抗体
WO2013173348A1 (fr) Anticorps à réaction croisée dirigés contre le virus de la dengue et leurs utilisations
JP2024506315A (ja) コロナウイルスのスパイクタンパク質を標的とする抗体
KR102017217B1 (ko) 중동호흡기증후군 코로나바이러스에 대한 항체 및 이를 이용한 항체역가 측정방법
CA3197642A1 (fr) Polypeptides ciblant sars-cov-2, compositions et methodes associees
CN113527473A (zh) 一种全人源单克隆抗体及其应用
WO2022216223A1 (fr) Vaccin et/ou anticorps pour infection virale
WO2023154824A1 (fr) Anticorps monoclonaux humains ciblant largement les coronavirus
EP3310816B1 (fr) Immunoglobulines conjuguées cys80
EP4353744A1 (fr) Anticorps contre le virus respiratoire syncytial et son utilisation
CN115087667B (zh) 特异性结合SARS-CoV-2的抗原结合蛋白
CN118103395A (zh) 泛特异性冠状病毒结合剂
WO2023111796A1 (fr) Anticorps sars-cov-2 pan-spécifiques et leurs utilisations
CN115260306A (zh) 靶向SARS-CoV-2受体结合基序的单克隆抗体及其识别抗原表位和应用
CN113651884A (zh) 人源化抗SARS-CoV-2单克隆抗体及其应用
US20210171613A1 (en) Clostridium difficile-specific antibodies and uses thereof
CN111606992A (zh) 一种抗呼吸道合胞病毒的全人源抗体
EP4230650A1 (fr) Anticorps capables de se lier à la protéine spike du coronavirus sars-cov-2
US20240228596A1 (en) Pan-specific corona virus binders
US20240101645A1 (en) Monoclonal antibodies against coronaviruses and uses thereof
Ying et al. Fully human single-domain antibody targeting a highly conserved cryptic epitope on the Nipah virus G protein
WO2024150074A2 (fr) Anticorps contre le coronavirus et leurs utilisations thérapeutiques

Legal Events

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

Ref document number: 22906770

Country of ref document: EP

Kind code of ref document: A1