Merck and Moderna report 99% manufacturing success and 42% lower recurrence risk for personalized melanoma vaccine in Phase 3 trial

Merck and Moderna announced that their personalized mRNA cancer vaccine, combined with Keytruda, was successfully manufactured for 99% of patients enrolled in a large Phase 3 study. The trial, called INTerpath-001, involved more than 1,100 participants with resected stage 2b to 4 melanoma.

The data presented at the European Society of Medical Oncology Congress showed the vaccine reduced the risk of recurrence or death by 42%, corresponding to a hazard ratio of 0.58. This represents a significant improvement over standard treatment for this high‑risk population.

Company officials highlighted that the ability to produce custom‑made vaccines at scale is critical for bringing this therapy to patients worldwide. The results suggest the approach could become a new option for melanoma care pending regulatory review.