Overview : BSI-585 is a novel bispecific antibody that blocks both PD-1 and ILT4 signaling which relieves the inhibition of tumor microenvironment on T cells and myeloid cells in tumors and enhances the immune response​. Potent in vivo anti-tumor efficacy was observed in mouse xenografts. BSI-585 was co-discovered by Biosion and Celldex under a collaboration in Mar 2021. Biosion owns Greater China rights for development and commercialization while Celldex owns ex-Greater China rights and is responsible for all the development cost from PCC to IND stage.

Development status : Celldex plans to file an IND in the US and Biosion plans to file an IND in China in 2H 2022.