Ivonescimab plus chemotherapy versus durvalumab plus chemotherapy as first-line treatment for advanced biliary tract cancer: A randomized, controlled, double-blinded, phase 3 trial (HARMONi-GI1)

HARMONi-GI1

Patient / Population Intervention / Exposure Comparison Outcome

In patients with advanced biliary tract cancer, ivonescimab plus chemotherapy improved overall survival compared with durvalumab plus chemotherapy.

N

682patients

Design

Phase 3, randomised 1:1, double-blinded trial in China of ivonescimab vs durvalumab, each with gemcitabine and cisplatin and then as maintenance, as first-line treatment for unresectable locally advanced or metastatic biliary tract cancer, stratified by disease status and primary tumour location (NCT06591520).

Endpoint

Overall survival.

ResultMedian OS with ivonescimab plus chemotherapy 14.9 vs 12.1 months with durvalumab plus chemotherapy (HR 0.75, 95% CI 0.61-0.92, P = 0.0031). Median PFS 8.4 vs 5.8 months (HR 0.61, 95% CI 0.51-0.72, P <0.0001). ORR 53.8% vs 32.5% (P <0.0001). The most common treatment-emergent adverse events were haematological toxicity, and no new safety signals were identified for ivonescimab.

Zhou J, Zheng T, Fan J, et al. Presented at ESMO Congress 2026, abstract LBA8, 25 October. Not yet published.

Discussion & critique

This double-blinded phase 3 trial met its hard primary endpoint of overall survival against durvalumab plus chemotherapy, which the abstract describes as the standard first-line treatment. The data come from a preplanned interim analysis with a median follow-up of 14.3 months, so the survival curves are still immature and the size of the benefit may shift with longer follow-up. The trial enrolled patients only in China, and the abstract reports no results by primary tumour location, although randomisation was stratified by it. Safety is described only in qualitative terms, with no rates of grade 3 or higher events or discontinuations, and the study was funded by Akeso Biopharma, Inc.