Personalized mRNA Cancer Vaccine Clears a Major Test—but Key Data Are Still Missing

Personalized mRNA Cancer Vaccine Clears a Major Test—but Key Data Are Still Missing
A personalized cancer vaccine has delivered its biggest result yet, raising hopes that mRNA technology can move from pandemic prevention into precision oncology. But Moderna and Merck’s announcement leaves the medical community waiting for the numbers that will show how large that benefit really is.

Investor enthusiasm was immediate: one report said Moderna shares doubled on the skin-cancer vaccine success.

The result follows encouraging earlier-stage evidence. Five-year Phase 2 data presented in June showed the vaccine regimen cut the risk of recurrence or death by 49% and the risk of distant metastasis or death by 59%, according to the report.

On Wednesday, the companies said their Phase 3 study met its primary goals in 1,137 patients with surgically removed stage IIB–IV melanoma. Patients received either the personalized treatment, intismeran—also known as mRNA-4157—plus Merck’s Keytruda, or Keytruda alone, in a double-blind, placebo-controlled trial. The combination extended recurrence-free survival and distant metastasis-free survival, the partners said.

The treatment is built around up to 34 mutations unique to each patient’s tumor. It uses synthetic mRNA to train the immune system to recognize those cancer-specific targets—a personalized “neoantigen therapy” built on the same platform Moderna used for its COVID-19 vaccine.

Trial leader Georgina Long called the findings “a landmark moment” with the potential to establish “a new treatment paradigm.” Merck’s research chief Dean Li said the outcome reinforced “the promise of a more personalized approach to cancer treatment.”

Outside scientists shared the excitement, but not the urge to declare victory early. Oxford cancer specialist Lennard Lee called it “the first positive Phase III trial of an individualized neoantigen therapy and an mRNA-based cancer treatment,” while stressing that overall-survival results, subgroup findings and quality-of-life data remain unavailable. Those details, due at a future medical meeting, will determine whether a striking trial announcement becomes a routine melanoma treatment.

Continue reading https://foxvector.com/stories/01a020dd-1d03-09a5-703f-01513648608e