Akeso, Inc. reported longer median overall survival with its investigational ivonescimab combination than with durvalumab in first-line advanced biliary tract cancer, based on a Phase III interim analysis.
In the intent-to-treat population, median overall survival was 14.9 months with ivonescimab plus chemotherapy and 12.1 months with durvalumab plus chemotherapy. Akeso reported a hazard ratio of 0.75 (95% confidence interval, 0.61 to 0.92; P=0.0031), which the company described as a 25% reduction in the risk of death. Akeso said an independent data monitoring committee reviewed the interim analysis.
The company also reported positive findings for progression-free survival, which measures how long patients live before their cancer worsens or they die, and objective response rate, the share of patients whose tumors shrink. In separate accounts of the European Society for Medical Oncology (ESMO) abstract, Xueqiu and Sina Finance reported median progression-free survival of 8.4 months with ivonescimab and 5.8 months with durvalumab, response rates of 53.8% and 32.5%, and median follow-up of 14.3 months. Xueqiu reported a progression-free-survival hazard ratio of 0.61 (95% confidence interval, 0.51 to 0.72; P<0.0001).
The results were presented at the ESMO 2026 Presidential Symposium in Madrid on Oct. 25. The disease category includes cancers of the bile ducts and gallbladder. ClinicalTrials.gov lists actual enrollment of 682 participants; its trial description says both groups received gemcitabine and cisplatin, alongside either AK112 (ivonescimab) or durvalumab. Summit Therapeutics has described the China-based study as sponsored by Akeso and said Akeso generated, managed and analyzed the data.
Durvalumab with gemcitabine and cisplatin is an established first-line treatment. In the planned interim analysis of the separate TOPAZ-1 trial, median overall survival was 12.8 months with that combination and 11.5 months with chemotherapy alone; ESMO described the regimen as a standard of care.
Summit says ivonescimab remains investigational in its U.S. and European license territories. Summit and the ECOG-ACRIN Cancer Research Group expect to start opening U.S. sites in the fourth quarter of 2026 for EA2251, a separate Phase II/III study comparing ivonescimab plus gemcitabine and cisplatin with either pembrolizumab or durvalumab plus the same chemotherapy.
