Summit reports ivonescimab trial data

• Summit Therapeutics reported updated overall survival results from the Phase III HARMONi trial for ivonescimab plus chemotherapy.
• The study showed an overall survival hazard ratio of 0.76 in the global intention-to-treat population.
• The company is evaluating ivonescimab as a treatment option for EGFR-mutated non-small cell lung cancer patients after prior EGFR therapy.

Summit Therapeutics (NASDAQ:SMMT) reported updated overall survival results from the global Phase III HARMONi clinical trial showing ivonescimab plus chemotherapy continued to demonstrate survival results in patients with EGFR-mutated advanced non-small cell lung cancer.

The updated analysis included data from patients previously treated with third-generation EGFR tyrosine kinase inhibitors and showed an overall survival hazard ratio of 0.76 in the global intention-to-treat population.

“Updated results from the global Phase III HARMONi study show that ivonescimab combined with chemotherapy continued to demonstrate a consistent overall survival improvement compared with placebo plus chemotherapy in patients with EGFR-mutated non-small cell lung cancer following prior treatment with a third-generation EGFR TKI,” said Antonio Passaro, M.D., Ph.D., Director of the Division of Thoracic Oncology at the European Institute of Oncology.

The June 2026 analysis showed a median follow-up of 23.2 months for western patients and 32.7 months for Asian patients, with the global overall survival hazard ratio reported at 0.76 (95% CI: 0.61–0.95; nominal p=0.0151).

Summit Therapeutics said the updated HARMONi results support continued evaluation of ivonescimab combined with chemotherapy for patients requiring additional treatment options after progression on EGFR-targeted therapies.

The HARMONi study is evaluating ivonescimab plus chemotherapy compared with placebo plus chemotherapy in patients with EGFR-mutated locally advanced or metastatic non-squamous non-small cell lung cancer.

Earlier analysis in April 2025 showed a positive overall survival trend but did not reach statistical significance, with a hazard ratio of 0.79, a median overall survival of 16.8 months for ivonescimab plus chemotherapy and 14 months for placebo plus chemotherapy.