New survival data supports ivonescimab treatment
Summit Therapeutics Inc. (NASDAQ:SMMT) shares gained 3% on Wednesday after the company released updated overall survival data from its global Phase III HARMONi trial evaluating ivonescimab in combination with chemotherapy for advanced lung cancer.
The study enrolled patients with EGFR-mutated, locally advanced or metastatic non-squamous non-small cell lung cancer whose disease had progressed after treatment with a third-generation EGFR tyrosine kinase inhibitor.
Updated results showed that patients treated in Western countries achieved an overall survival hazard ratio of 0.76, matching the outcome previously reported in the Asian patient population.
Longer follow-up reinforces earlier findings
The latest analysis, based on data collected through June 2026, included a median follow-up period of 23.2 months for Western patients, significantly longer than the 9.2 months available at the time of the primary analysis in April 2025.
The hazard ratio of 0.76 was consistent across both the overall intention-to-treat population and the subgroup of Western participants.
Asian patients in the trial had a median follow-up period of 32.7 months.
FDA review continues ahead of November decision
The primary overall survival analysis, completed in April 2025, showed that ivonescimab combined with chemotherapy produced a favourable trend, with a hazard ratio of 0.79. However, the result narrowly missed statistical significance, recording a p-value of 0.057.
Median overall survival reached 16.8 months for patients receiving ivonescimab plus chemotherapy, compared with 14.0 months for those treated with placebo alongside chemotherapy.
Summit said the updated survival analysis has been submitted to the U.S. Food and Drug Administration as part of its ongoing review of the company’s Biologics License Application.
The BLA currently has a PDUFA target action date of November 14, 2026.
Safety profile remains consistent
The company also noted that the HARMONi study had previously met one of its two primary endpoints by demonstrating a statistically significant improvement in progression-free survival.
According to Summit, ivonescimab continued to exhibit an acceptable and manageable safety profile that remained consistent with earlier Phase III findings, with no new safety concerns identified in the latest data review.