BSI-082

BSI-082 is a fully human, antagonistic monoclonal antibody targeting signal regulatory protein alpha (SIRPα). It is designed to block the interaction between SIRPα and CD47, thereby enabling tumor-associated macrophages and dendritic cells to resume their phagocytic activity against tumor cells. This mechanism aims to overcome the "don't eat me" signal that many tumors use for immune evasion. BSI-082 demonstrates strong binding affinity to multiple human SIRPα variants (V1/V2/V8), covering over 90% of the human population. Unlike some other agents in this space, it does not bind SIRPγ but does bind SIRPβ. Preclinical studies have shown potent antitumor efficacy—especially in combination with other monoclonal antibodies or immunotherapies—and favorable pharmacokinetic and safety profiles. The drug was discovered by Biosion using its H³ antibody discovery platform and has received FDA IND clearance for clinical development in hematologic and solid tumors[1][2][3][4][6].