BL-B16D1 (Chengdu Bailidote Biological Pharmaceutical Company Limited)

BL-B16D1 is a bispecific antibody-drug conjugate (ADC) developed by Chengdu Bailidote Biopharmaceutical, a subsidiary of Sichuan Biokin Pharmaceutical (Baili Tianheng) and SystImmune. The molecule is designed to simultaneously target Claudin-18.2 (CLDN18.2) and Human Epidermal Growth Factor Receptor 2 (HER2), two antigens frequently overexpressed in various solid tumors, including gastric and gastroesophageal junction cancers. BL-B16D1 utilizes the company's proprietary ADC platform, featuring a topoisomerase I inhibitor payload (a camptothecin derivative designated as 'D1') conjugated to the bispecific antibody via a cleavable linker. This dual-targeting strategy aims to improve therapeutic efficacy and selectivity while minimizing off-target toxicity. It is currently undergoing Phase I clinical evaluation for the treatment of locally advanced or metastatic solid tumors.