Summit Therapeutics falls after mixed data from late-stage study of Ivonescimab plus chemotherapy cancer trial in EGFR-mutated Lung Cancer (NSCLC): Update

Summit Therapeutics Inc. (NASDAQ: SMMT) (“Summit,” “we,” or the “Company”) announced (May 30, 2025) topline results from the Phase III clinical trial, HARMONi, the first global Phase III study evaluating ivonescimab, successfully met the progression-free survival (PFS) primary endpoint and showed a positive trend in the other primary endpoint, overall survival (OS). HARMONi is a multiregional, double-blinded, placebo-controlled, Phase III study sponsored by Summit evaluating ivonescimab plus platinum-doublet chemotherapy 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) who have progressed after treatment with a 3rd generation EGFR tyrosine kinase inhibitor (TKI). This is a clinical setting with a patient population where PD-1 monoclonal antibodies have previously been unsuccessful in Phase III global clinical trials in showing either a P...