Summit Therapeutics has released updated overall survival data from its phase 3 HARMONi trial as the FDA moves toward a landmark decision on ivonescimab.
The new analysis, based on a data cut-off in June 2026, shows the overall survival hazard ratio in a Western subgroup of 165 patients improved to 0.76.
That figure marks a meaningful shift from a hazard ratio of 0.84 recorded at a September 2025 data cut-off and 0.98 at the trial’s primary analysis in April 2025.
The latest readout indicates a 24% reduction in the risk of death for ivonescimab plus chemotherapy versus chemotherapy alone in patients with previously treated EGFR-mutated nonsquamous non-small cell lung cancer.
Summit noted the results do not carry statistical significance, though the trend across successive analyses points in a consistently positive direction.
The updated Western subgroup hazard ratio now matches that of the entire trial population of 438 patients, a detail Summit highlighted in its announcement to investors and regulators.
The FDA is currently reviewing Summit’s application for ivonescimab, which would be the first approval in the United States for both the drug and the PD-1xVEGF bispecific antibody class.
The agency has set a target decision date of November 14, 2026, though the updated analysis may constitute a major amendment that could trigger a three-month extension to the review period.
“The HARMONi results we announced today are a new analysis that was just recently made available to the FDA,” a Summit spokesperson said. “We think it’s important context for our submission.”
Shares in Summit Therapeutics (SMMT) rose approximately 3.1% on Wednesday morning following the announcement, reflecting cautious optimism among investors watching the regulatory process closely.
The update comes as investor attention remains fixed on the broader HARMONi-3 trial, which is evaluating ivonescimab as a first-line treatment for non-small cell lung cancer on a global basis.
Summit shares experienced a sharp selloff in May after HARMONi-3 surprisingly missed statistical significance on progression-free survival during an interim analysis, rattling market confidence in the drug’s wider commercial prospects.
The company has said it expects final progression-free survival and interim overall survival readouts from HARMONi-3 during the current year, though a Summit spokesperson confirmed there is no timing update on that front at this stage.