Fully human Anti-SIGLEC15 Antibody BSI-060T used for solid tumors population groups

Partnering objectives
Seeking a collaboration opportunity with a company that has a strategic interest in the treatment of solid tumors

Field: Treatment of solid tumors, including metastatic head and neck squamous cell carcinoma (HNSCC), non-small cell lung cancer (NSCLC), ovarian cancer, melanoma, triple-negative breast cancer, endometrial cancer, squamous cell carcinoma, colorectal cancer

Technology and MOA
MOA: blocks the immunosuppressive effect of Siglec-15
Siglec-15 is an immunomodulatory target expressed on a restricted set of myeloid cells in the tumor microenvironment. The drug candidate prevents immune suppression caused by S15 which is done by targeting M2 macrophages, S15-induced myeloid cells and S15-positive tumors. The drug candidate elicits the therapeutic intervention by decreasing inflammatory cytokines associated with enhanced tumor growth, promote T cell proliferation and restore T cell function.

Marketing opportunity
At present, the clinical application of tumor immunotherapy is very effective, which can significantly alleviate and improve the condition of cancer patients. However, for the current mainstream PD-(L)1 antibodies, a considerable part of patients still fail to achieve the expected therapeutic effect. Data from Siglec15’s laboratory studies show that Siglec-15 can regulate immune suppression in a manner independent of the PD-1 / PD-L1 pathway, sustainably inhibit T cell activity, and may meet the main characteristics of normalized immunotherapy. This indicates that anti-siglec15 antibody may have potential for use in patients who do not express PD-L1, and is a relatively safe anti-cancer pathway.

Differentiable treatment with potential to be first/ best in class
BSI-060T is a high-affinity fully human anti-Siglec15 monoclonal antibody with superior bioactivity to the benchmark.

Indications
• Colorectal Cancer
• Endometrial Cancer
• Head And Neck Cancer Squamous Cell Carcinoma;
• Melanoma
• Merkel Cell Carcinoma
• Non-Small Cell Lung Cancer
• Ovarian Cancer
• Squamous Cell Carcinoma
• Triple-Negative Breast Cancer (TNBC)

Data
Key parameters of fully human anti-Siglec15 (S15) antibody BSI-060T as compared to NC318:
• Exhibits 6-fold higher affinity to huS15 and cyno-S15 than NC318
• Shows superior cellular bioactivity than NC318 (on reversing T cell proliferation inhibition by S15 ex vivo assay)
• In vivo efficacy and PK/PD studies are on-going…

Intellectual property
For discussion under CDA.