Merck/Moderna cancer vaccine cuts risk of death or recurrence from melanoma by over 40%

Oct 22 (Reuters) - An mRNA cancer vaccine developed by Moderna MRNA.O and Merck MRK.N in combination with a widely used immunotherapy cut the risk of death or recurrence of melanoma by 42% and disease spread by 38%, according to data from a large trial, potentially paving the way for a new era of personalized treatment.

The trial of more than 1,100 patients is the first to show that the combination of a vaccine based on mutations unique to each patient's tumor plus a drug that helps the immune system fight cancer can keep the disease at bay. The vaccine was tested along with Merck's blockbuster immunotherapy Keytruda, among the world's biggest-selling medicines.

Moderna and Merck announced in August that the treatment had succeeded in the trial but did not provide details.

The results, based on patient data for the first two years after treatment, are scheduled to be presented on Saturday at the European Society for Medical Oncology meeting in Madrid.

Several Wall Street analysts said before the meeting that investors were looking for the combination to cut the risk of recurrence by 40% or more.