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# Moderna/Merck Report Positive Data on Melanoma Vaccine
- URL: https://www.fdaweb.com/moderna-merck-report-positive-data-on-melanoma-vaccine/
- Published: 2026-01-20T12:00:00.000Z
- Updated: 2026-09-14T15:31:05.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5160518

Moderna and Merck say that updated five-year follow-up data show that their personalized mRNA cancer vaccine candidate, intismeran autogene, significantly reduced the risk of melanoma recurrence or death when used in combination with Merck’s immunotherapy Keytruda (pembrolizumab), compared with Keytruda alone, according to the companies. In a pre-planned analysis of the Phase 2b KEYNOTE-942/mRNA-4157-P201 trial, adjuvant treatment with intismeran autogene plus Keytruda cut the risk of recurrence or death by 49% in patients with completely resected, high-risk stage III or IV melanoma.

The results extend earlier findings from the same trial, which previously showed improved recurrence-free survival at roughly two and three years of follow-up. According to the companies, the safety profile of the combination therapy remains consistent with what has already been reported.

The trial evaluated intismeran autogene — also known as mRNA-4157 or V940 — an investigational individualized neoantigen therapy designed for each patient based on the genetic mutations in their tumor. The therapy was administered alongside Keytruda, Merck’s anti-PD-1 antibody, in patients who had undergone complete surgical resection of melanoma but remained at high risk of relapse.

Executives from both companies said the durability of the benefit is particularly notable given the substantial risk of recurrence in patients with Stage III or IV melanoma after surgery. They described the five-year data as an important validation of the potential for individualized mRNA-based therapies to enhance long-term outcomes when combined with established immuno-oncology agents.