AT-65474

AT-65474 is an antibody-drug conjugate (ADC) developed by Axcynsis Therapeutics. It targets Claudin 6 (CLDN6), a tight junction protein that is aberrantly expressed in several solid tumors, including ovarian cancer. The drug functions as a CLDN6 inhibitor, aiming to deliver cytotoxic agents specifically to CLDN6-positive tumor cells while sparing normal tissues. Preclinical studies have shown that AT-65474 exhibits strong binding affinity, high internalization rates, superior in vitro cytotoxicity, and robust bystander killing effects compared to benchmark ADCs. In xenograft models of ovarian cancer, it demonstrated significantly higher efficacy than comparator ADCs[1][2][5]. As of early 2025, the highest development phase for AT-65474 is Phase 1 clinical trials for advanced malignant solid neoplasms and CLDN6-positive solid tumors[1][2].