BsAb5003

BsAb5003 is a novel humanized bispecific monoclonal antibody (BsAb) designed for the treatment of multiple myeloma. It simultaneously targets the G-protein-coupled receptor class 5 member D (GPRC5D), which is highly expressed on malignant plasma cells, and the CD3 epsilon subunit of the T-cell receptor complex. By binding both targets, BsAb5003 acts as a T-cell engager, redirecting cytotoxic T cells to recognize and eliminate GPRC5D-positive myeloma cells. This interaction triggers T-cell activation, the release of proinflammatory cytokines, and specific tumor cell lysis. Preclinical studies have demonstrated that BsAb5003 is effective against both newly diagnosed and relapsed/refractory multiple myeloma samples and exhibits synergistic antitumor activity when combined with immunomodulatory drugs (IMiDs).