Humanized Anti-SIRPα Antibody BSI-050 used for the treatment of solid tumors

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

Field: Treatment of solid tumors, such as Non-Small Cell Lung Carcinoma, Breast Cancer etc

Technology and MOA
MOA: Highly specific Anti-SIRPα antagonistic antibody with minimum binding to SIRPb or SIRPg, acts as a SIRPα/CD47 inhibitor

SIRPα is expressed on myeloid cells known as myeloid derived suppressor cells (MDSC) and some macrophage cells known as tumor associated macrophages (TAM), key immune suppressor cells in cancer tumor growth. Interaction of SIRPα (on macrophages) with CD47 (on tumor cells) prevents the elimination by macrophages of tumors cells.

The drug candidate by specifically targeting SIRPα, it transforms MDSC and TAM suppressor cells into non-suppressor cells. As a result, the immune system is reactivated and inhibits tumor growth.

Marketing opportunity
Cancer immunotherapy utilizes the power and specificity of the host’s immune system to eliminate malignant diseases and has become one of the most promising therapeutic interventions in the field. Tumor cells frequently develop resistance to chemotherapy and immunotherapy, which leads to incomplete tumor regression, dissemination, and metastasis of drug-resistant cancer cell clones. One example of how tumor cells escape myeloid cell-dependent killing is to up-regulate the antiphagocytic “don’t eat me” signal CD47. Whereas CD47 is expressed on tumors and normal tissues, its ligand, signal regulatory protein-α (SIRPα), has a limited expression pattern, with high levels of expression on macrophages, dendritic cells, neutrophils, and neurons.

Global market for Non-Small Cell Lung Cancer should reach $117.05bn in 2025 from $33.16 bn in 2018 at a compound annual growth rate (CAGR) of 19.8%, from 2018 to 2025

Differentiable treatment with potential to be first/ best in class
BSI050 exhibits Potent SIRPα/CD47 blocking activity than benchmark – BI-765063 (Boehringer Ingelheim International GmbH) – currently in Phase-I clinical trial. Different from BI-765063, BSI050 has high-affinity and is highly specific to SIRPα with no binding or minimum binding to SIRPb and SIRPg.

Indications
• Non-Small Cell Lung Carcinoma
• Breast Cancer
• Ovarian Cancer
• Renal Cell Carcinoma
• Colorectal Cancer
• Pancreatic Cancer

Data
Key parameters of fully human anti-SIRPa antibody BSI050 as compared to BI-765063:

• BSI050 binds huSIRPa with high affinity at 10 nM scale;
• Binds to huSIRPa isoform v2/v8 and cynomolgus SIRPa with high affinity;
• No binding to SIRPb or SIRPg, differentiated from BI-765063 which also binds to SIRPb;
• Comparable SIRPa/CD47 antagonist activity;

Development Stage
Preclinical, and is expected to file IND in Q3/2022

Mode of Administration
Injectable

Intellectual property
For discussion under CDA.