Hutchmed launches development programme for next-gen therapy platform

(Sharecast News) - Hutchmed said on Wednesday that it has initiated a global phase one clinical development programme for HMPL-A251, marking the first clinical-stage candidate from its next-generation Antibody-Targeted Therapy Conjugate platform. The AIM-traded firm said the first-in-human phase one/2a, open-label, multicentre study was evaluating HMPL-A251 as a monotherapy in adult patients with unresectable, advanced or metastatic HER2-expressing solid tumours.

Study sites are located in the United States and China, with the first patient having received the initial dose on 16 December in China.

The trial comprises a phase one dose-escalation stage and a phase 2a dose-expansion and optimisation stage, with the initial focus on assessing safety, tolerability and defining the maximum tolerated and recommended doses.

HMPL-A251 is a first-in-class PI3K/PIKK-HER2 ATTC, combining a highly selective PI3K/PIKK inhibitor payload with a humanised anti-HER2 IgG1 antibody via a cleavable linker.

Hutchmed said the design was intended to deliver targeted pathway inhibition directly to HER2-expressing tumour cells, potentially overcoming the systemic toxicity and narrow therapeutic index that have historically limited PI3K/PIKK inhibitors.

Secondary endpoints of the study include preliminary anti-tumour activity, pharmacokinetics and immunogenicity.

Hutchmed said preclinical data for HMPL-A251, presented earlier this year, supported the translational potential of the ATTC platform and its broader application across a family of future drug candidates.

The company said the ATTC platform represented a next-generation approach to precision oncology, combining monoclonal antibodies with proprietary small-molecule inhibitor payloads to deliver dual mechanisms of action while aiming to reduce off-tumour toxicity and improve long-term tolerability.

At the close on Wednesday, shares in Hutchmed China were up 1% at 202p.

Reporting by Josh White for Sharecast.com.