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US-12617852-B2 - PVRIG binding protein and its medical uses

US12617852B2US 12617852 B2US12617852 B2US 12617852B2US-12617852-B2

Abstract

A PVRIG binding protein and its medical uses. Specifically, an anti-PVRIG single-domain antibody and an anti-PVRIG and -TIGIT bispecific antibody, pharmaceutical compositions comprising the antibodies, a method for treating cancer, and pharmaceutical uses.

Inventors

  • Yuan Lin
  • Kan Lin
  • Xinsheng JIN
  • Man Zhang
  • Cheng Liao

Assignees

  • JIANGSU HENGRUI PHARMACEUTICALS CO., LTD.
  • SHANGHAI SHENGDI PHARMACEUTICAL CO., LTD.

Dates

Publication Date
20260505
Application Date
20210312
Priority Date
20200313

Claims (20)

  1. 1 . A Poliovirus Receptor-Related Immunoglobulin Domain-Containing Protein (PVRIG) binding protein, comprising at least one immunoglobulin single variable domain comprising: a CDR1, a CDR2 and a CDR3 having the amino acid sequences of the CDR1, the CDR2, and the CDR3, respectively, of the heavy chain variable region having the amino acid sequence selected from the group consisting of SEQ ID NOs: 3 and 80-84; or a CDR1, a CDR2 and a CDR3 having the amino acid sequences of the CDR1, the CDR2, and the CDR3, respectively, of the heavy chain variable region having the amino acid sequence selected from the group consisting of SEQ ID NOs: 2 and 75-79; or a CDR1, a CDR2 and a CDR3 having the amino acid sequences of the CDR1, the CDR2, and the CDR3, respectively, of the heavy chain variable region having the amino acid sequence selected from the group consisting of SEQ ID NOs: 4 and 86-90; or a CDR1, a CDR2 and a CDR3 having the amino acid sequences of the CDR1, the CDR2, and the CDR3, respectively, of the heavy chain variable region having the amino acid sequence selected from the group consisting of SEQ ID NOs: 5 and 91-95; or a CDR1, a CDR2 and a CDR3 having the amino acid sequences of the CDR1, the CDR2, and the CDR3, respectively, of the heavy chain variable region having the amino acid sequence selected from the group consisting of SEQ ID NOS: 6 and 96-100; wherein the CDR1, the CDR2 and the CDR3 are defined according to Kabat, IMGT, Chothia, AbM or Contact numbering scheme.
  2. 2 . The PVRIG binding protein according to claim 1 , wherein the immunoglobulin single variable domain is a heavy chain single-domain antibody (VHH).
  3. 3 . The PVRIG binding protein according to claim 1 wherein the immunoglobulin single variable domain comprises the amino acid sequence of: any one of SEQ ID NOs: 3 and 80-84; or any one of SEQ ID NOs: 2 and 75-79; or any one of SEQ ID NOs: 4 and 86-90; or any one of SEQ ID NOs: 5 and 91-95; or any one of SEQ ID NOs: 6 and 96-100; or has at least 90% sequence identity to any one of the aforementioned sequences.
  4. 4 . The PVRIG binding protein according to claim 1 , further comprising a human immunoglobulin Fc region, wherein the Fc region is an Fc region of human IgG1 or IgG4.
  5. 5 . A PVRIG/TIGIT binding protein, comprising a first antigen-binding domain specifically binding to PVRIG and a second antigen-binding domain specifically binding to T Cell Immunoreceptor with Ig and ITIM Domains (TIGIT), wherein the first antigen-binding domain comprises the PVRIG binding protein according to claim 1 .
  6. 6 . The PVRIG/TIGIT binding protein according to claim 5 , wherein the immunoglobulin single variable domain in the first antigen-binding domain comprises the amino acid sequence of: any one of SEQ ID NOs: 3 and 80-84; or any one of SEQ ID NOs: 2 and 75-79; or any one of SEQ ID NOs: 4 and 86-90; or any one of SEQ ID NOs: 5 and 91-95; or any one of SEQ ID NOs: 6 and 96-100; or has at least 90% sequence identity to any one of the aforementioned sequences.
  7. 7 . The PVRIG/TIGIT binding protein according to claim 5 , wherein the second antigen-binding domain specifically binding to TIGIT comprises a heavy chain variable region (VH) and a light chain variable region (VL), wherein: the heavy chain variable region comprises an HCDR1, an HCDR2 and an HCDR3 comprising the amino acid sequences of SEQ ID NOs: 121, 122 and 123, respectively, and the light chain variable region comprises an LCDR1, an LCDR2 and an LCDR3 comprising the amino acid sequences of SEQ ID NOs: 124, 125 and 126, respectively; or the heavy chain variable region comprises an HCDR1, an HCDR2 and an HCDR3 comprising the amino acid sequences of SEQ ID NOs: 115, 116 and 117, respectively, and the light chain variable region comprises an LCDR1, an LCDR2 and an LCDR3 comprising the amino acid sequences of SEQ ID NOs: 118, 119 and 120, respectively; or the heavy chain variable region comprises an HCDR1, an HCDR2 and an HCDR3 comprising the amino acid sequences of SEQ ID NOs: 127, 128 and 129, respectively, and the light chain variable region comprises an LCDR1, an LCDR2 and an LCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131 and 132, respectively; or the heavy chain variable region comprises an HCDR1, an HCDR2 and an HCDR3 comprising the amino acid sequences of SEQ ID NOs: 133, 134 and 135, respectively, and the light chain variable region comprises an LCDR1, an LCDR2 and an LCDR3 comprising the amino acid sequences of SEQ ID NOs: 136, 137 and 138, respectively; or the heavy chain variable region comprises an HCDR1, an HCDR2 and an HCDR3 comprising the amino acid sequences of SEQ ID NOs: 139, 140 and 141, respectively, and the light chain variable region comprises an LCDR1, an LCDR2 and an LCDR3 comprising the amino acid sequences of SEQ ID NOs: 142, 143 and 144, respectively.
  8. 8 . The PVRIG/TIGIT binding protein according to claim 7 , wherein the heavy chain variable region of the second antigen-binding domain specifically binding to TIGIT comprises the amino acid sequence of any one of SEQ ID NOs: 145-147 or an amino acid sequence having at least 90% sequence identity thereto, and the light chain variable region comprises the amino acid sequence of any one of SEQ ID NOs: 148-149 or an amino acid sequence having at least 90%-sequence identity thereto.
  9. 9 . The PVRIG/TIGIT binding protein according to claim 8 , wherein the second antigen-binding domain specifically binding to TIGIT comprises a heavy chain comprising an amino acid sequence at least 90% identical to the amino acid sequence of SEQ ID NO: 102; and a light chain comprising an amino acid sequence at least 90% identical to the amino acid sequence of SEQ ID NO: 103.
  10. 10 . The PVRIG/TIGIT binding protein according to claim 7 wherein: the immunoglobulin single variable domain of the first antigen-binding domain specifically binding to PVRIG is located at N-terminal of the heavy chain variable region of the second antigen-binding domain specifically binding to TIGIT; the immunoglobulin single variable domain of the first antigen-binding domain specifically binding to PVRIG is located at C-terminal of the heavy chain variable region of the second antigen-binding domain specifically binding to TIGIT; the immunoglobulin single variable domain of the first antigen-binding domain specifically binding to PVRIG is located at N-terminal of the light chain variable region of the second antigen-binding domain specifically binding to TIGIT; or the immunoglobulin single variable domain of the first antigen-binding domain specifically binding to PVRIG is located at C-terminal of the light chain variable region of the second antigen-binding domain specifically binding to TIGIT.
  11. 11 . The PVRIG/TIGIT binding protein according to claim 10 , wherein the immunoglobulin single variable domain of the first antigen-binding domain is linked, directly or via a linker, to the second antigen-binding domain.
  12. 12 . The PVRIG/TIGIT binding protein according to claim 5 , comprising a first polypeptide chain and a second polypeptide chain, wherein: the first polypeptide chain comprises the amino acid sequence of any one of SEQ ID NOs: 108-112 and 114, and the second polypeptide chain comprises the amino acid sequence of SEQ ID NO: 103; or the first polypeptide chain comprises the amino acid sequence of SEQ ID NO: 104 or 105, and the second polypeptide chain comprises the amino acid sequence of SEQ ID NO: 103; or the first polypeptide chain comprises the amino acid sequence of SEQ ID NO: 102, and the second polypeptide chain comprises the amino acid sequence of SEQ ID NO: 106 or 107.
  13. 13 . An anti-PVRIG antibody or an antigen-binding fragment thereof, comprising the immunoglobulin single variable domain according to claim 1 .
  14. 14 . A polynucleotide encoding the PVRIG binding protein according to claim 1 .
  15. 15 . A host cell comprising the polynucleotide according to claim 14 .
  16. 16 . A method for preparing a PVRIG binding protein-comprising expressing the polynucleotide according to claim 14 in a host cell and isolating the expressed PVRIG binding protein from the host cell.
  17. 17 . A pharmaceutical composition comprising the PVRIG binding protein according to claim 1 , and a pharmaceutically acceptable excipient, diluent or carrier.
  18. 18 . A method for treating a cancer or delaying progression of the cancer, comprising administering to a subject in need thereof, an effective amount of the PVRIG binding protein according to claim 1 , wherein the amount is effective to treat or delay the cancer.
  19. 19 . A method for activating NK cells, γδT cells or Th1 cells, comprising administering to a subject in need thereof, an effective amount of the PVRIG binding protein according claim 1 .
  20. 20 . A method for increasing generation of interferon-γ or secretion of pro-inflammatory cytokine, comprising administering to a subject in need thereof, an effective amount of the PVRIG binding protein according to claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Section 371 of International Application No. PCT/CN2021/080470, filed on Mar. 12, 2021, which published in the Chinese language on Sep. 16, 2021, under International Publication No. WO 2021/180205 A1, which claims priority to Chinese Patent Application No. CN 202010174835.4 filed on Mar. 13, 2020. Each disclosure is incorporated herein by reference in its entirety. REFERENCE TO SEQUENCE LISTING SUBMITTED ELECTRONICALLY This application contains a sequence listing that is submitted electronically via EFS-Web as an ASCII formatted sequence listing with a file name “065827-6US1 Update ST25-v2” and a creation date of Nov. 18, 2025 and having a size of 147,726 bytes. The sequence listing, submitted via EFS-Web, is part of the specification and is herein incorporated by reference in its entirety. TECHNICAL FIELD The present disclosure relates to a PVRIG binding protein, e.g., an anti-PVRIG antibody and a bispecific antibody formed thereby together with anti-TIGIT antibody, and use thereof as a medicament for treating cancer. BACKGROUND Cancer is the greatest health challenge facing human society for a long term today. Traditional therapies such as surgery, chemotherapy and radiotherapy have shown little efficacy in treating disseminated solid tumors. Tumor immunotherapy is a hot spot in the field of tumor treatment, where tumor immunotherapy of T cells is in its central position. The tumor immunotherapy features fully utilizing and mobilizing killer T cells in a tumor patient to kill the tumor, and it is probably the most effective and the safest way to treat tumors. Tumor immunotherapy currently exhibits great promise for the treatment of several different types of cancers, including disseminated metastatic tumors. The activation of T cells in humans adopts a system of two signaling pathways. In addition to providing the first signal to T cells by presenting MHC-antigen peptides via antigen presenting cells (APCs), a series of co-stimulatory molecules are also needed to provide the second signal, thereby enabling the T cells to generate normal immune response. This dual-signaling pathway system plays a crucial role in the balance of the immune system in vivo, and it strictly regulates the body's generation of different immune responses to self and non-self antigens. If the second signal provided by the co-stimulatory molecules is absent, there will be T cell non-response or sustained specific immune response, resulting in tolerance. Thus, the second signaling pathway plays a very critical regulatory role throughout the body's immune response. PVRIG, also known as CD112R, is a protein expressed on the cell surface and belongs to the B7/CD28 superfamily, just like TIGIT, CD96, CD226, etc., and it plays an important role in the immune system. It comprises an extracellular region, a transmembrane region and an intracellular region. When its ligand PVRL2 (also known as CD112) binds to PVRIG, the ITIM domain of PVRIG intracellular region will be activated, thus enabling PVRIG to play the role of immunosuppression. PVRIG is mainly expressed on the surface of CD4+ T cells, CD8+ T cells and NK cells. PVRIG and its ligand PVRL2 are highly expressed in many solid tumors, including lung cancer, breast cancer, ovarian cancer, renal cancer, gastric cancer, endometrial cancer, head and neck cancer, and the like. The expression of PVRIG in these cancers is highly correlated with TIGIT and PD-1. Similar to PD-1 and TIGIT, PVRIG-positive T cells are also Eomes-positive and Tbet-negative, indicating that PVRIG is associated with T cell depletion. Thus, PVRIG may represent a new immune checkpoint in addition to PD-1 and TIGIT and plays a redundancy role. In vitro cell experiments and mouse models show that the knockout or inhibition of mouse PVRIG can effectively inhibit the growth of tumors and generate coordination action with PD-1 and TIGIT inhibitors. Another target of interest, TIGIT, is highly expressed on lymphocytes, including tumor infiltrating lymphocytes (TILs) and Treg infiltrating different types of tumors. It has been proved that engagement of TIGIT signaling to its cognate ligand PVR (also known as CD155) directly suppresses NK cell cytotoxicity through its cytoplasmic ITIM domain. PVR is also widely expressed in tumors, suggesting that the TIGIT-PVR signaling axis may be a dominant immune escape mechanism for cancer. However, no PVRIG/TIGIT bispecific antibody drug has entered the clinic trial phase at present. COM701 by Compugen is the first humanized hybridoma antibody against PVRIG in the world approved by FDA to enter the clinic trial phase, and it is currently in phase I clinical stage and used for treating cancer. Surface Oncology is also developing an anti-PVRIG antibody, SRF-813. Anti-TIGIT antibodies include tiragolumab by Genentech, BMS-986207 developed by Ono Pharmaceutical in cooperation with BMS, MK-7684 by MSD, EOS-884448 by iTeos Therapeuti