HutchMed partners with GSK to develop HMPL-A830

HONG KONG and FLORHAM PARK, N.J., HutchMed, a leading biopharmaceutical company, has announced a significant collaboration with GlaxoSmithKline (GSK) to develop and commercialize HMPL-A830, a first-in-class KRAS-EGFR Antibody-Targeted Therapy Conjugate (ATTC). This strategic partnership is set to accelerate the clinical development of HMPL-A830, which is expected to enter phase I trials later this year.

The licensing agreement, signed on September 3, 2026, grants GSK worldwide rights (excluding Mainland China, Hong Kong, Macau, and Taiwan) to develop and commercialize HMPL-A830. The therapy is designed to target colorectal, pancreatic, and lung cancers, which are known to have high incidences of KRAS-altered tumors.

Under the terms of the deal, GSK will pay HutchMed an upfront payment of $110 million. Additionally, GSK is eligible for development, regulatory, and commercial milestone payments, which could total up to $1.295 billion. Furthermore, GSK will pay royalties on its net sales of the drug, with HutchMed retaining full development and commercialization rights in the specified regions.

"HutchMed is proud to partner with GSK, a global leader in biopharmaceuticals, to advance innovative cancer treatments," said Johnny Cheng, Acting CEO and CFO of HutchMed. "Our ATTCs combine the precision of monoclonal antibodies with our proprietary small-molecule inhibitor payloads, offering dual mechanisms of action. HMPL-A830 is our third drug candidate from these novel platforms and the first to be licensed to a global partner, marking a significant step in our mission to provide safer and more effective treatment options."

Dr. Hesham Abdullah, Senior Vice President and Global Head of Oncology R&D at GSK, expressed enthusiasm for the collaboration. "This agreement reflects GSK's commitment to advancing innovative oncology therapies. The dual KRAS-EGFR mechanism of HMPL-A830 has the potential to significantly improve current treatment options. We look forward to working with HutchMed to progress this innovative asset through development."

HMPL-A830 is designed to deliver a KRAS inhibitor directly to EGFR-expressing tumors while simultaneously blocking EGFR and KRAS signaling. This dual mechanism aims to enhance efficacy, durability, and tolerability in patients with KRAS-altered tumors, a significant unmet need in oncology.

HutchMed will oversee the initial global phase I development program, set to commence in the second half of 2026. GSK will be responsible for all subsequent clinical development and commercialization activities outside of Mainland China, Hong Kong, Macau, and Taiwan.

The collaboration is expected to bring significant advancements in the treatment of KRAS-driven cancers. "This partnership underscores HutchMed's commitment to innovation and its ability to deliver cutting-edge therapies to patients," added Cheng.

HutchMed will host webcasts to provide more details on the collaboration today, September 3, 2026. The webcasts will be available in Chinese (Putonghua) and English, with registration details accessible at www.hutch-med.com/event.

BofA Securities is acting as exclusive financial advisor to HutchMed in this transaction.

HutchMed's ATTCs represent a next-generation approach to precision oncology, combining targeted therapies to achieve synergistic anti-tumor activity. Unlike traditional antibody-drug conjugates, ATTCs leverage antibody-guided delivery and tumor-specific payload release, enhancing accessibility to tumors and reducing off-tumor toxicity.

KRAS mutations, driving multiple solid tumors, are a significant focus in cancer research. Approximately 44% of colorectal cancer, 34% of lung adenocarcinoma, and up to 89% of pancreatic ductal adenocarcinoma patients have KRAS alterations. These mutations regulate key downstream pathways, contributing to cell differentiation, proliferation, and survival.

EGFR, a receptor tyrosine kinase, plays a crucial role in tumor cell proliferation, survival, and disease progression across various solid tumors. Signaling through EGFR activates the downstream RAS/MAPK and PI3K/AKT/mTOR pathways, providing a rationale for targeting both EGFR and KRAS to improve therapeutic outcomes.

Forward-looking statements in this announcement reflect HutchMed's expectations and are subject to various risks and uncertainties, including the success of clinical trials, regulatory approvals, and market acceptance. HutchMed encourages readers to consider these factors in evaluating its forward-looking statements.

For further discussion, please visit www.hutch-med.com or follow us on LinkedIn.

End of Announcement.

*Note: The forward-looking statements are subject to various risks and uncertainties, and readers are advised to consider these carefully. HutchMed cannot guarantee the accuracy or reliability of the statements. For detailed information, please refer to the company's official disclosures and filings. *

*Disclaimer: This announcement is for informational purposes only and does not constitute an offer to sell or a solicitation of an offer to buy any securities.*

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