Merck and Moderna’s postoperative melanoma vaccine strategy landed a major ESMO-style late-breaking update, with the combination reducing risk of death or recurrence by 42% versus Keytruda alone after a median follow-up of about two years. The reported landmark metric was recurrence-free survival, building on earlier interim Phase 3 signals. The companies reported that 82.2% of patients receiving the combination were relapse-free at two years versus 70% in the Keytruda-only arm, while overall survival is still maturing. The result keeps the focus on adding immunotherapy benefit in the adjuvant setting after surgery. Industry impact: the update intensifies competition in adjuvant melanoma and raises the bar for next-generation combinations targeting minimal residual disease and recurrence risk reduction. Editorial note: details are based on the provided report text describing the ESMO leak-driven press release.