Akeso ivonescimab meets OS endpoint in 682-patient biliary tract trial

Akeso's ivonescimab plus chemotherapy met the primary overall survival endpoint in a 682-patient Phase III trial for advanced biliary tract cancer, beating durvalumab plus chemotherapy.

"This is a major breakthrough for the treatment of biliary tract cancer," Dr. Michelle Xia, founder, chairwoman, president and CEO of Akeso, said.

The randomized, controlled, double-blinded, multicenter registrational study (AK112-309/HARMONi-GI1) evaluated ivonescimab (Yidafang), a PD-1/VEGF bispecific antibody, plus chemotherapy versus durvalumab, a PD-L1 monoclonal antibody, plus chemotherapy as first-line treatment for advanced biliary tract cancer. A pre-specified interim analysis assessed by the Independent Data Monitoring Committee showed the study met its primary endpoint of overall survival with clinically meaningful and statistically significant results. All key secondary endpoints of progression-free survival and objective response rate were also met.

Durvalumab plus chemotherapy is the preferred first-line immunotherapy regimen recommended by international guidelines for advanced biliary tract cancer. HARMONi-GI1 is the first Phase III study in this disease to demonstrate a statistically significant OS benefit versus the global gold standard PD-L1 plus chemotherapy regimen. The study enrolled 682 subjects with baseline characteristics consistent with real-world distribution and balanced between treatment and control groups.

The positive result marks ivonescimab's first successful Phase III readout in gastrointestinal tumors, following four positive Phase III results in lung cancer. Akeso shares rose 3.5 percent on the announcement, with short selling at HK$133.51 million, an 18.2 percent ratio.

Ivonescimab is approved and commercially available in China for non-small cell lung cancer indications. Summit Therapeutics (NASDAQ: SMMT), which holds license rights to the drug in North America, South America, Europe, the Middle East, Africa and Japan, noted the results in a separate statement. Summit has a Biologics License Application under FDA review for ivonescimab in EGFR-mutated NSCLC, with a PDUFA date of Nov. 14, 2026.

More than 4,000 patients have been treated with ivonescimab in clinical studies globally, and over 70,000 in commercial settings in China. Akeso is running additional Phase III studies in colorectal cancer, pancreatic cancer, triple-negative breast cancer, head and neck squamous cell carcinoma and small cell lung cancer.

Detailed results from HARMONi-GI1 will be presented at an upcoming international academic conference and published in a peer-reviewed journal. The outcome expands ivonescimab's addressable market beyond lung cancer into gastrointestinal solid tumors, where the drug now has a positive Phase III readout in two tumor types. Investors will watch for the full data presentation and potential regulatory filings in China.

This article is for informational purposes only and does not constitute investment advice.