Immunome (NASDAQ:IMNM) shares soared about 30% after the biotech group reported encouraging topline findings from its Phase 3 RINGSIDE study evaluating varegacestat in patients with desmoid tumors.
The pivotal trial achieved its primary endpoint, showing a statistically meaningful improvement in progression-free survival versus placebo. Results indicated an 84% reduction in the risk of disease progression or death, with a hazard ratio of 0.16 and a p-value below 0.0001.
All major secondary endpoints were also met. Varegacestat delivered an objective response rate of 56%, which the company said is the highest response rate recorded to date in a randomized clinical trial for this patient group.
The treatment, an investigational oral gamma secretase inhibitor taken once daily, was generally well tolerated and showed a manageable safety profile. The most frequently reported side effects were diarrhea (82%), fatigue (44%), rash (43%), nausea (35%) and cough (34%), with the majority classified as mild to moderate in severity.
“The progression-free survival benefit, high response rate and reduction in tumor volume with varegacestat in the RINGSIDE trial are striking. These findings elevate the role of GSIs and confirm varegacestat could become standard of care in the treatment of desmoid tumors,” said Mrinal M. Gounder, sarcoma medical oncologist at Memorial Sloan Kettering Cancer Center and RINGSIDE primary investigator.
Following the positive readout, Immunome said it plans to file a New Drug Application with the U.S. Food and Drug Administration in the second quarter of 2026. The company also expects to present further data from the RINGSIDE trial at a forthcoming major medical conference.