Personalized mRNA Cancer Vaccine Reduces Melanoma Recurrence by 42% in Landmark Trial

A world-first international trial has shown that adding a personalized therapeutic cancer vaccine, intismeran, to pembrolizumab immunotherapy after surgery for high-risk melanoma reduced the risk of recurrence or death by 42% compared to pembrolizumab alone. This mRNA-based individualized neoantigen therapy is designed to train the immune system to recognize and fight cancer cells. The results were updated with ESMO images on October 25, 2026.