Moderna and Merck reveal their personalized mRNA cancer vaccine slashes death and recurrence rates by 42%

A new trial shows that personalized mRNA vaccines against melanoma reduce the risk of death or recurrence by 42% compared to standard treatment. Moderna and Merck announced Thursday that their personalized mRNA vaccines against melanoma, the deadliest form of skin cancer, have shown significant results in reducing the risk of death or recurrence by 42% compared to standard treatment. The results are a significant advance in melanoma treatment; Merck and Moderna are already engaging with regulatory authorities to get the vaccine approved. More broadly, the vaccine’s success bolsters hope that mRNA vaccines and individualized cancer-targeting medicines offer a new paradigm for cancer therapies.

Moderna CEO Stéphane Bancel said in a statement that from the beginning, we believed mRNA technology could make it possible to develop cancer treatments uniquely matched to each patient’s tumor. The trial results mark a defining moment for that vision and show what’s possible when we rethink how medicines are made. They also reinforce our conviction that mRNA has the potential to fundamentally change how we treat cancer, he said.

In August, Moderna and Merck reported that the vaccine has succeeded in the trial, but held off reporting details until the data could be presented at an upcoming scientific conference. That conference is the European Society of Medical Oncology, starting now in Madrid, Spain. The data was scheduled for presentation on Saturday, but after an oncology news site reported the results early, breaking the embargo, the companies released the top-line results. The full data has been accepted for publication in the New England Journal of Medicine.

As Ars reported earlier, the Phase 3 trial included 1,137 patients who had stage IIB, IV melanoma that had been surgically removed prior to entering the trial. Patients were randomized 2-1 to receive either a combination treatment including the personalized mRNA vaccine with a standard treatment, or the standard treatment alone. The standard treatment was Merck’s established monoclonal antibody cancer treatment Keytruda.