Moderna, Merck report melanoma vaccine trial results

Moderna and Merck said a personalized mRNA vaccine, added to Keytruda after surgery for high-risk melanoma, reduced the relative risk of recurrence or death by 42% over the first two years in a Phase 3 trial involving more than 1,100 patients. The companies reported that 82.2% of patients who received intismeran with Keytruda were cancer-free at two years, compared with 70% of those treated with Keytruda alone. The reported combination also reduced the relative risk of melanoma spreading to distant organs or tissues by 38% versus Keytruda alone. The findings are from a randomized trial of patients whose melanoma had been surgically removed. All participants received Keytruda, Merck’s immunotherapy; they were assigned to receive either the personalized vaccine or a placebo alongside it. The vaccine, called intismeran, was given in nine doses, according to the trial descriptions. Intismeran is designed around mutations identified in an individual patient’s tumor. The resulting vaccine is intended to train the immune system to recognize tumor-related proteins and attack cancer cells if they return. The approach differs from vaccines that prevent infections linked to cancer, such...