ATG-125

**ATG-125** is an investigational, preclinical B7-H3 × PD-L1 bispecific antibody-drug conjugate developed by Antengene for solid tumors. It comprises a human IgG1 anti-B7-H3 antibody with a C-terminal PD-L1-directed single-chain variable fragment and is conjugated through a cleavable GGFG linker to a DXd DNA topoisomerase I inhibitor payload at an approximate drug-to-antibody ratio of 4. Dual binding promotes tumor-cell targeting and internalization, intracellular payload release and cytotoxicity, while PD-L1 blockade is intended to restore antitumor T-cell activity. ([aacrjournals.org](https://aacrjournals.org/cancerres/article/86/7_Supplement/5599/780839/Abstract-5599-ATG-125-a-novel-B7H3-PD-L1))