Merck and Moderna say their individualized mRNA therapy plus Keytruda cut melanoma recurrence or death risk by 42%

As of 8:40 a.m. ET, Friday, Oct. 23, 2026

Merck and Moderna said Thursday, Oct. 22, that their investigational individualized mRNA therapy, intismeran autogene, combined with Merck's Keytruda reduced the risk of recurrence or death by 42% compared with Keytruda alone in patients with completely resected stage IIB-IV melanoma in a Phase 3 trial.

At the primary analysis, after a median follow-up of 24.6 months, the hazard ratio for recurrence-free survival was 0.58 (95% CI, 0.45-0.75), the companies said. The combination also reduced the risk of distant metastasis or death by 38% (hazard ratio 0.62), they said.

The two-year recurrence-free survival rate was 82.2% with the combination and 70.0% with Keytruda alone, according to the release. Overall survival data are not yet mature, the companies said, and the study is continuing.

The INTerpath-001 trial enrolled 1,137 patients who were randomized 2:1 after surgery to receive intismeran plus Keytruda or placebo plus Keytruda, the companies said. Intismeran is designed using a sample of each patient's tumor to target its unique mutations, according to the release.

Safety

Grade 3 to 5 treatment-related adverse events occurred in 14.2% of patients receiving the combination and 13.4% of those receiving Keytruda alone, the companies said. The most common adverse events in the combination arm were fever, injection site pain and fatigue.

Presentation

The companies said the results will be presented during Presidential Symposium I at the European Society for Medical Oncology Congress 2026 (presentation LBA1) and have been accepted for publication in The New England Journal of Medicine.

"The transformative INTerpath-001 results have the potential to make a foundational shift in how we treat patients with earlier-stage melanoma in the adjuvant setting," said Professor Georgina Long, the study's principal investigator and medical director of Melanoma Institute Australia.

"These results reinforce our conviction that mRNA has the potential to fundamentally change how we treat cancer," said Stéphane Bancel, Moderna's chief executive.

What is not known

Whether the combination improves overall survival is not yet known; the companies said those data are not mature.