Overview : BSI-501 is a novel, highly differentiated, bispecific antibody targeting two key driver targets in auto-immune diseases. It targets TH2-mediated disorders through the inhibition of IL4/13 axis, which has been validated in several diseases. It also targets mast cells (MCs, also a strong mediator of TH2 responses) which are known to be activated and in higher numbers in many inflammatory indications, thus brings additional benefit. BSI-501 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 : Pre-clinical development, Celldex plans to file an IND in 2024.