Chi-Med announced that the company will launch a global Phase I clinical development program for HMPL-A251. HMPL-A251 is the world's first PI3K/PIKK-HER2 antibody-targeted conjugation drug. It consists of a highly selective and potent PI3K/PIKK inhibitor as a payload and a humanized anti-HER2 IgG1 antibody conjugated through a lyzable ligator. The study will be conducted in the US and China, and the first patient received the first dose of medication in China on December 16, 2025. This trial aims to evaluate the safety and tolerability of HMPL-A251 monotherapy for adult patients with unresectable advanced or metastatic solid tumors with HER2 expression.

Chi-Med announced that the company will launch a global Phase I clinical development program for HMPL-A251. HMPL-A251 is the world's first PI3K/PIKK-HER2 antibody-targeted conjugation drug. It consists of a highly selective and potent PI3K/PIKK inhibitor as a payload and a humanized anti-HER2 IgG1 antibody conjugated through a lyzable ligator. The study will be conducted in the US and China, and the first patient received the first dose of medication in China on December 16, 2025. This trial aims to evaluate the safety and tolerability of HMPL-A251 monotherapy for adult patients with unresectable advanced or metastatic solid tumors with HER2 expression.