Summit Touts Updated HARMONi Data Showing Consistent Survival Benefit for Ivonescimab in Western NSCLC Patients

Summit Therapeutics has highlighted updated data from its global Phase III HARMONi trial for ivonescimab, a first-in-class PD-1/VEGF bispecific antibody, in patients with EGFR-mutated advanced non-squamous non-small cell lung cancer treated with prior third-generation EGFR TKIs.

The latest analysis, with a June 2026 data cutoff, shows a consistent overall survival benefit for Western patients treated with ivonescimab plus platinum-doublet chemotherapy versus chemotherapy alone, with a hazard ratio of 0.76 in both the full intention-to-treat population and the Western subgroup.

Western patients had a median follow-up of 23.2 months in this updated analysis, bringing their survival performance into alignment with the previously reported OS benefit in Asian patients, who had longer follow-up at earlier analyses.

Median overall survival was 16.8 months for ivonescimab plus chemotherapy versus 14.0 months for placebo plus chemotherapy at the primary analysis, a trend that tightened and stabilized in the new readout, with the Western OS HR improving from 0.84 (September 2025) and 0.98 (primary analysis) to 0.76 while remaining numerically rather than statistically significant.

The updated OS, combined with statistically significant progression-free survival benefit (HR 0.52) and favorable safety profile, supports Summit’s positioning of ivonescimab as a global, region‑consistent therapy ahead of U.S. regulatory review.