New phase 3 results for Moderna and Merck’s personalized mRNA melanoma vaccine support earlier findings showing a 49% lower risk of recurrence or death.

Today, Aug. 19, 2026, Moderna's personalized cancer vaccine met its late-stage goal, with the company and Merck planning an FDA submission.

Moderna and Merck are developing a treatment using an mRNA-based cancer vaccine called intismeran that is designed to be tailored to individual patients based on unique mutations within their tumors. In current studies, they are pairing it with Keytruda, a immunotherapy drug made by Merck.

The late-stage melanoma trial with Merck’s Keytruda shows both lower recurrence and less spread, with no new safety signals—this is the clearest proof yet that Moderna’s personalized mRNA can work as an add-on to a major checkpoint therapy.

Merck (NYSE: MRK), known as MSD outside of the United States and Canada, and Moderna, Inc. (NASDAQ: MRNA) today announced positive topline results from the Phase 3 INTerpath-001 trial evaluating adjuvant treatment with intismeran autogene (intismeran;

Moderna shares more than doubled Wednesday after it announced initial results from a study of an experimental cancer treatment that would be the first of its kind if approved by regulators.