
HUTCHMED (NASDAQ:HCM) announced the initiation of global Phase I/IIa clinical trials for HMPL-A251, the first clinical candidate from its next-generation Antibody-Targeted Therapy Conjugate (ATTC) platform.
The first patient was dosed in China on Dec. 16, 2025, marking the beginning of the study, which will include sites in both the U.S. and China.
The clinical trial is registered under NCT07228247.
HMPL-A251 is a HER2-targeted antibody-drug conjugate that carries a selective PI3K/PIKK inhibitor payload via a cleavable linker, designed to deliver potent, targeted therapeutic action against HER2-expressing solid tumors.
The open-label trial aims to evaluate the safety, tolerability, maximum tolerated dose (MTD), recommended dose for expansion (RDE), as well as preliminary efficacy, pharmacokinetics, and immunogenicity.
Preclinical data for HMPL-A251 were presented at the 2025 AACR-NCI-EORTC conference, generating excitement around the potential of this novel therapy.
The trial's results are closely watched as they could pave the way for a new treatment option in the field of solid tumor oncology.