KJ015

KJ015 is an **anti-HER2 biparatopic bispecific antibody** independently developed by Shanghai BaoPharma (Shanghai Bao Pharmaceutical). It is engineered using common light chain technology to bind two non-overlapping epitopes of the HER2 (ERBB2) receptor, enabling high-affinity clustering interactions on the cell membrane. This unique design allows KJ015 to exert enhanced anti-tumor effects compared to the combination of trastuzumab and pertuzumab, especially in HER2-positive tumors. KJ015 maintains antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC) similar to current anti-HER2 therapies, but with improved efficacy in preclinical models and robust expression/stability for subcutaneous administration. It is being developed as a subcutaneous injection for the treatment of HER2-positive solid tumors, with lead indications including gastroesophageal adenocarcinoma, breast cancer, colorectal cancer, bile duct cancer, and others. KJ015 is currently undergoing Phase 1 clinical trials for safety, pharmacokinetics, and preliminary efficacy in a range of HER2-expressing cancers[1][2][3][5][7][8][9][10].