Ivonescimab plus platinum-doublet chemotherapy - (HARMONi)

July 22, 2026: Summit Therapeutics Inc. (NASDAQ: SMMT) reported an updated overall survival (OS) analysis from the global Phase III HARMONi trial of ivonescimab plus platinum-doublet chemotherapy vs placebo plus chemotherapy in previously treated (post third-generation EGFR TKI) EGFR-mutated, locally advanced/metastatic non-squamous NSCLC. The trial previously met the PFS primary endpoint; OS is co-primary.

OS updates by data cut:

• Apr 2025 (primary OS analysis): HR 0.79 (95% CI 0.62–1.01; p=0.057); median OS 16.8 vs 14.0 months (ivonescimab+chemo vs placebo+chemo).
• Sept 2025: HR 0.78 (95% CI 0.62–0.98; nominal p=0.0332); median OS unchanged vs Apr 2025.
• June 2026: HR 0.76 in the ITT population and HR 0.76 in western patients; western median follow-up 23.2 months. Detailed data are intended for an upcoming medical meeting and have been provided to FDA.

Regulatory: Summit’s BLA (based on HARMONi) was submitted and accepted for filing in Jan 2026; FDA PDUFA goal action date is Nov 14, 2026. Safety in the latest cut was described as acceptable/manageable with no new signals.