Drugmakers Merck and Moderna announced Thursday that their personalized mRNA vaccine for melanoma, the deadliest form of skin cancer, lowered the risk of death or recurrence by 42 percent compared with standard treatment in a late-stage clinical trial.
The companies describe the result as a significant step forward in treating the disease, and they are already in discussions with regulators about securing approval for the vaccine. The outcome also strengthens hopes that mRNA vaccines and other individualized, cancer-targeting medicines could open a new approach to cancer therapy more broadly.
Moderna CEO Stéphane Bancel said in a statement that the company had believed from the outset that mRNA technology could be used to create cancer treatments "uniquely matched to each patient's tumor." He called the trial results "a defining moment for that vision" and said they show "what's possible when we rethink how medicines are made." The findings, he added, "reinforce our conviction that mRNA has the potential to fundamentally change how we treat cancer."
The announcement follows an earlier disclosure in August, when Moderna and Merck said the vaccine had succeeded in the trial but withheld the details until they could be presented at a scientific meeting. That meeting is the European Society of Medical Oncology congress, which is getting under way in Madrid, Spain.
The data had been scheduled for presentation on Saturday. After an oncology news site reported the results ahead of time and broke the embargo, the companies put out the top-line findings themselves. The complete data set has been accepted for publication in the New England Journal of Medicine.
The Phase 3 trial enrolled 1,137 patients with stage IIB to stage IV melanoma. All of them had undergone surgery to remove the cancer before joining the study.
Participants were randomly assigned in a 2-to-1 ratio to one of two groups. The larger group received the personalized mRNA vaccine together with a standard treatment, while the smaller group received the standard treatment alone. That standard therapy was Keytruda, Merck's established monoclonal antibody cancer drug.
