First Immunotherapy-Based Regimen to Show Statistically Significant and Clinically Meaningful PFS Benefit in a Global Phase III Study of EGFR-Mutated NSCLC after Third-Generation EGFR TKI Progression

Updated OS Data to Be Presented at WCLC 2026

Summit Therapeutics Inc. (NASDAQ:SMMT) today announced the publication of primary analysis results from the global Phase III HARMONi clinical trial in The Lancet Oncology. In HARMONi, ivonescimab in combination with platinum-doublet chemotherapy demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to placebo plus platinum-doublet chemotherapy in patients with epidermal growth factor receptor (EGFR)-mutated, locally advanced or metastatic non-squamous non-small cell lung cancer (NSCLC) whose disease progressed following treatment with a third-generation EGFR tyrosine kinase inhibitor (TKI).

The manuscript, titled "Ivonescimab plus chemotherapy versus placebo plus chemotherapy in patients with advanced EGFR-mutated non-small cell lung cancer after EGFR-TKI progression (HARMONi): a randomised, double-blind, multi-centre phase 3 trial," reports primary efficacy and safety results from the study conducted at 114 cancer centers and hospitals across Asia, Europe, and North America. The study was designed to evaluate whether ivonescimab plus chemotherapy could improve clinical outcomes in a setting where treatment options remain limited after progression on EGFR-directed therapy.