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EP-4739353-A2 - ANTI-GRP78 ANTIBODIES AND THEIR USES

EP4739353A2EP 4739353 A2EP4739353 A2EP 4739353A2EP-4739353-A2

Abstract

The present disclosure relates to an anti-glucose-regulated protein 78 (GRP78) antibody or an antigen-binding fragment thereof. The present disclosure also relates to a method for treating and/or preventing a disease and/or disorder caused by or related to GRP78 activity or signaling, and a method or kit for detecting GRP78 or a cancer in a sample.

Inventors

  • WU, CHIA-CHENG
  • TSAI, YA-WEI
  • LIN, TZU-YIN
  • LO, Chia-Hsiang

Assignees

  • UCT Bioscience Co., Ltd.

Dates

Publication Date
20260513
Application Date
20240703

Claims (20)

  1. 1. An isolated antibody or antigen-binding fragment thereof that is specific for an epitope in glucose- regulated protein 78 (GRP78); wherein the isolated antibody or antigen-binding fragment thereof comprises complementarity determining regions (CDRs) of a heavy chain variable region or CDRs of a light chain variable region, wherein the CDRs of the heavy chain variable region comprise: CDRH1 having the amino acid sequence of SEQ ID NO: 1, CDRH2 having the amino acid sequence of SEQ ID NO: 2, and CDRH3 having the amino acid sequence of SEQ ID NO: 3; and wherein the CDRs of the light chain variable region comprise: CDRL1 having the amino acid sequence of SEQ ID NO: 4, CDRL2 having the amino acid sequence of SEQ ID NO: 5, and CDRL3 having the amino acid sequence of SEQ ID NO: 6.
  2. 2. The isolated antibody or antigen-binding fragment thereof of claim 1, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 7 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 7, and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 8 orthe amino acid sequence with at least about 95% identity to SEQ ID NO: 8.
  3. 3. The isolated antibody or antigen-binding fragment thereof of claim 1, which is an Fab fragment, an Ffab' fragment, an ScFv fragment, a monoclonal antibody, a chimeric antibody, a humanized antibody or a human antibody.
  4. 4. The isolated antibody or antigen-binding fragment thereof of claim 3, which is an ScFv fragment comprising the heavy chain variable region having the amino acid sequence of SEQ ID NO: 7 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 7, the light chain variable region having the amino acid sequence of SEQ ID NO: 8 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 8, and a linker linking the heaving chain variable region and the light chain variable region, wherein the linker comprises the amino acid sequence of SEQ ID NO: 21 or 12, orthe amino acid sequence with at least about 95% identity to SEQ ID NO: 21 or 12.
  5. 5. The isolated antibody or antigen-binding fragment thereof of claim 1, which is linked to a second specific binding domain for a second target, wherein the second specific binding domain comprises a T-cell targeting domain.
  6. 6. The isolated antibody or antigen-binding fragment thereof of claim 5, wherein the T-cell targeting domain is specific for CD3.
  7. 7. The isolated antibody or antigen-binding fragment thereof of claim 5, wherein the T-cell targeting domain comprises CDRs of a heavy chain variable region and CDRs of a light chain variable region, wherein the heavy-chain variable region comprises HCDR1 having the amino acid sequence of SEQ ID NO: 13, HCDR2 having the amino acid sequence of SEQ ID NO: 14, and HCDR3 having the amino acid sequence of SEQ ID NO: 15; and the light-chain variable region comprises LCDR1 having the amino acid sequence of SEQ ID NO: 16, LCDR2 having the amino acid sequence of SEQ ID NO: 17, and LCDR3 having the amino acid sequence of SEQ ID NO: 18.
  8. 8. The isolated antibody or antigen-binding fragment thereof of claim 5, wherein the T-cell targeting domain comprises the amino acid sequence of SEQ ID NO: 19 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 19.
  9. 9. The isolated antibody or antigen-binding fragment thereof of claim 5, which comprises a first heavy chain having the amino acid sequence of SEQ ID NO: 9 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 9, a second heavy chain having the amino acid sequence of SEQ ID NO: 10 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 10, and a light chain having the amino acid sequence of SEQ ID NO: 11 or the amino acid sequence with at least about 95% identity to SEQ ID NO: 11.
  10. 10. The isolated antibody or antigen-binding fragment thereof of claim 5, which comprises the amino acid sequence of SEQ ID NO: 22 or 20, or the amino acid sequence with at least about 95% identity to SEQ ID NO: 22 or 20.
  11. 11. The isolated antibody or antigen-binding fragment thereof of claim 1, which is expressed on a surface of a cell.
  12. 12. The isolated antibody or antigen-binding fragment thereof of claim 1, which is conjugated with a therapeutic agent.
  13. 13. A vector encoding the isolated antibody or antigen-binding fragment thereof of claim 1.
  14. 14. A genetically engineered cell expressing the isolated antibody or antigen-binding fragment thereof of claim 1.
  15. 15. The genetically engineered cell of claim 14, which is an immune cell or a stem cell.
  16. 16. The genetically engineered cell of claim 15, which is a T cell.
  17. 17. Use of a pharmaceutical composition in the manufacture of a medicament for treating, prophylactic treating and/or preventing a disease and/or disorder caused by or related to GRP78 activity or signaling in a subject in need thereof, wherein the pharmaceutical composition comprises an effective amount of the isolated antibody or antigen-binding fragment thereof of any one of claims 1 to 12 or the genetically engineered cell of claim 14, and optionally a pharmaceutically acceptable carrier.
  18. 18. The use of claim 17, wherein the disease is a cancer selected from the group consisting of lung cancer, breast cancer, prostate cancer, colorectal cancer, gastric cancer, pancreatic cancer, ovarian cancer, hepatocellular carcinoma, renal cell carcinoma, testicular cancer, melanoma, leukemia, and papillary thyroid cancer.
  19. 19. A method for detecting expression of GRP78 or a cancer, comprising contacting the sample with the isolated antibody or antigen-binding fragment thereof of any of claims 1 to 12.
  20. 20. A kit for detecting GRP78 or a cancer in a sample, comprising the isolated antibody or antigenbinding fragment thereof of any of claims 1 to 12.

Description

ANTI-GRP78 ANTIBODIES AND THEIR USES PRIORITY INFORMATION [0001] The subject application claims priority to and benefit of U.S. Provisional Patent Application No. 63/511,711, filed July 3, 2023, the content of which is incorporated herein by reference in its entirety. SEQUENCE LISTING [0002] The instant application contains a Sequence Listing which is submitted electronically in .xml format and is hereby incorporated by reference in its entirety. FIELD OF THE INVENTION [0003] The present disclosure relates to novel antibodies, particularly to antibodies which is specific for glucose-regulated protein 78 (GRP78). The present disclosure also relates to uses of such antibodies for suppressing tumor growth and metastasis. BACKGROUND OF THE INVENTION [0004] Cancer is a leading cause of death and an important barrier to increasing life expectancy worldwide. Cancer targeted drug delivery and therapeutic approaches aimed at tumors hold promise in diminishing or halting tumor progression in living organisms, enabling them to enjoy extended and healthier lifespans. Nevertheless, numerous anti-tumor medications also exhibit toxicity towards non-tumor cells, leading to challenging and undesirable side effects. Consequently, there exists a requirement within the field for a method to selectively deliver antitumor agents exclusively to tumor cells, with the objective of minimizing tumor cell proliferation. [0005] Glucose-regulated protein 78 (GRP78) is primarily a chaperone protein located within the endoplasmic reticulum (ER), assisting in the proper folding of proteins by aiding misfolded protein targeting and facilitating protein assembly. However, under cellular stress, GRP78 is transported to the cell surface (csGRP78), where it interacts with various ligands and initiates diverse intracellular pathways. Consequently, the expression of csGRP78 is associated with cancer and contributes to the maintenance and progression of the disease. Notably, the external exposure of csGRP78 prompts the production of autoantibodies, as observed in patients with prostate or ovarian cancer, indicating that the ability to target csGRP78 has an impact on tumor development. Given that csGRP78 is present on the surface of cancer cells but not normal cells in vivo, it represents a promising target for therapeutic antibody approaches. [0006] However, the production of antibodies specific to GRP78 can be challenging. GRP78 is expressed on the cell surface of embryonic stem cells and homozygote knockout of GRP78 leads to embryonic lethality which means that high affinity GRP78 specific antibody producing B cells would be subject to clonal deletion or clonal anergy during normal B cell development. In addition, GRP78 is highly conserved among vertebrate species. Human GRP78 is 99% identical to primate GRP78 and 98% identical to rodent GRP78. This makes it more difficult to generate high affinity human GRP78 specific antibodies by animal immunization. Overall, the production of antibodies specific to GRP78 requires careful consideration to ensure the generation of reliable and specific antibodies for research or therapeutic applications. SUMMARY OF THE INVENTION [0007] Embodiments of the disclosure relate to anti-GRP78 antibodies that is specific for GRP78, as well as methods of using such antibodies in treatment of cancers. By specifically binding GRP78, antibodies as disclosed herein are able to be used to treat cancers that is caused by or related to GRP78 activity or signaling, including lung cancer, breast cancer, prostate cancer, colorectal cancer, gastric cancer, pancreatic cancer, and ovarian cancer. [0008] Accordingly, the present disclosure provides an isolated antibody or antigen-binding fragment thereof that is specific for an epitope in GRP78; wherein the isolated antibody or antigen-binding fragment thereof comprises complementarity determining regions (CDRs) of a heavy chain variable region or CDRs of a light chain variable region, wherein the CDRs of the heavy chain variable region comprise: CDRH1 having the amino acid sequence of SEQ ID NO: 1 or the amino acid sequence with at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to SEQ ID NO: 1, CDRH2 having the amino acid sequence of SEQ ID NO: 2 or the amino acid sequence with at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to SEQ ID NO: 2, and CDRH3 having the amino acid sequence of SEQ ID NO: 3 or the amino acid sequence with at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to SEQ ID NO: 3; or wherein the CDRs of the light chain variable region comprise: CDRL1 having the amino acid sequence of SEQ ID NO: 4 or the amino acid sequence with at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to SEQ ID NO: 4, CDRL2 having the amino acid sequence of SEQ ID NO: 5 or the amino acid sequence with at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to SEQ