Moderna and Merck reported on Oct. 22 that a customized cancer vaccine for people with late-stage melanoma can reduce the risk of cancer recurrence or death over two years by 42% compared to current treatment.

The results will be presented at the European Society of Medical Oncology meeting in Madrid on Oct. 24.

The study involved more than 1,130 people with Stage 2B to Stage 4 melanoma, all of whom had their tumors surgically removed. Some were then randomly assigned to have a cancer vaccine custom-made after their tumors had been genetically sequenced. They received that vaccine, called intismeran, once every three weeks for up to nine doses, along with Keytruda, a checkpoint inhibitor, every six weeks for up to nine cycles, for about a year. Others were randomly assigned to receive a placebo vaccine and Keytruda.

Intismeran, developed jointly by Moderna and Merck, represents a new way to harness the immune system in cancer, by training immune cells to recognize 34 specific proteins on tumor cells.…