Personalized mRNA vaccine cuts melanoma recurrence risk by 42% in trial
A trial of the mRNA-based vaccine intismeran showed a 42% reduction in melanoma recurrence two years after surgery when added to standard therapy.
A late-stage study involving more than 1,100 high-risk melanoma patients found that adding the personalized mRNA vaccine intismeran to standard post-surgery treatment reduced the risk of cancer returning by 42% after two years. Participants received the vaccine in nine doses spaced three weeks apart, while all patients continued on Merck’s immunotherapy Keytruda. Two years later, 82% of those who received the vaccine remained free of recurrence compared with 70% of those who received Keytruda alone.
The vaccine is custom-made for each patient by identifying unique tumour mutations and targeting the resulting neoantigens, prompting the immune system to recognize and attack any re-emerging cancer cells. Researchers said the approach represents a new direction for cancer immunotherapy.
"The field has been looking for a win and I think this one is a big one," said Dr. Hussein Tawbi of MD Anderson Cancer Center, one of the study investigators.
The trial’s safety profile was similar to that of mRNA COVID-19 vaccines, with most side effects limited to sore arms and fatigue. Moderna and Merck are consulting regulatory agencies about potential approval, though pricing details have not been disclosed.
Shares of Moderna fell 18% after the full results were released, but remained well above levels seen before the initial announcement in August.