Overview
- Moderna and Merck reported an interim Phase 3 readout on Wednesday that met the trial’s primary endpoint of recurrence‑free survival and a key secondary endpoint of distant metastasis‑free survival in patients with completely resected stage IIB–IV melanoma.
- The vaccine, called intismeran, is a personalized 'neoantigen' mRNA shot made from mutations found in each patient’s removed tumor and given alongside Merck’s immunotherapy Keytruda; individualized doses are manufactured in a multi‑week process.
- Companies said no new safety signals emerged in the interim analysis and that the combination was generally well tolerated in the trial of 1,137 high‑risk patients.
- Moderna and Merck will present full numerical and subgroup data at an upcoming medical meeting, continue to follow patients for overall survival, and are engaging regulators to discuss possible filings.
- The result is the first positive late‑stage readout for an individualized mRNA cancer vaccine and could shift attention and investment to mRNA oncology, though questions remain about long‑term survival, commercial manufacturing scale, cost, and applicability to other cancers.