The B cell activating factor receptor BAFF-R (B cell activating factor of the TNF-family receptor) is a member of the TNF receptor superfamily, which is primarily involved in the development of B lymphocytes and the survival of mature B cells.

ESG401 is Escugen's first ADC in the clinical stage of development. It features an innovative stable and degradable linker that significantly reduces off-target toxicity. Clinical data suggest that ESG401 has a higher tolerable dose than other ADCs targeting the same antigen, with lower incidence and severity of off-target and on-target toxicities, demonstrating a clear safety advantage.