Personalized mRNA Cancer Vaccine Plus Immunotherapy Reduces Melanoma Recurrence Risk by 42%

Melanoma is a type of skin cancer that can spread to other parts of the body. Even after surgery removes a tumour, some patients remain at risk of recurrence because microscopic cancer cells may persist. Treatments given after surgery aim to reduce this risk.

The personalised mRNA vaccine is designed using information about mutations in an individual patient's tumour. It aims to train the immune system to recognise tumour-specific targets, while pembrolizumab helps immune cells mount an attack against cancer. The two treatments therefore work through different but potentially complementary mechanisms.

In the reported Phase 3 trial, the combination reduced the risk of recurrence or death by 42% compared with pembrolizumab alone. The companies also reported a reduction in the risk of cancer spreading. These results are promising, but relative risk reductions should not be confused with the absolute probability that an individual patient will benefit.

The findings were announced by the companies, and detailed results require careful review of the full trial data, adverse effects and duration of follow-up. The companies were preparing regulatory submissions, so the combination should not be described as newly approved on the basis of this announcement alone.

Patients should discuss established melanoma treatment options with their oncology team and should not delay recommended care while waiting for an investigational vaccine.