ATG-125 (Antengene)

**ATG-125** is an Antengene preclinical B7-H3 × PD-L1 bispecific antibody-drug conjugate for solid tumors. The molecule combines a human IgG1 anti-B7-H3 antibody with a C-terminal PD-L1-targeting single-chain variable fragment and delivers a cleavable-linker topoisomerase I inhibitor payload. It is designed to promote tumor-selective internalization and intracellular payload release while blocking B7-H3- and PD-L1-associated immunosuppressive signaling, thereby combining direct cytotoxic activity with immune activation. Antengene reported preclinical binding, internalization, cytotoxicity, T-cell activation, and xenograft antitumor activity. ([antengene.com](https://www.antengene.com/static/upload/sofa/20260318/b3a206cf006defad520f0cb32b41834c.pdf))