Moderna and Merck’s Personalized Cancer Vaccine Cuts Melanoma Recurrence Risk by 42% in Pivotal Trial

NEW YORK, Oct. 22 (TodayViralUSA) — A personalized mRNA cancer vaccine developed by Moderna and Merck cut the risk of melanoma returning or patients dying by 42% when added to Merck’s immunotherapy Keytruda, according to detailed late-stage trial results the companies released Thursday.

The data, from the Phase 3 INTerpath-001 trial of more than 1,100 patients, are the first large-scale evidence that a vaccine tailored to the mutations in each patient’s own tumor, combined with a drug that unleashes the immune system, can help keep cancer at bay, Reuters reported.

The key numbers

Patients in the trial had high-risk stage IIB to IV melanoma that had been surgically removed. After a median follow-up of about two years, those who received the vaccine, known as intismeran autogene, plus Keytruda had a 42% lower risk of recurrence or death than those given Keytruda alone, the companies said. The combination also reduced the risk of the cancer spreading to distant organs, or death, by 38%.

• At two years, 82.2% of patients on the combination were alive without recurrence, compared with 70.0% on Keytruda alone.
• Distant metastasis-free survival at two years was 88.5% versus 80.2%.
• Overall survival data are not yet mature, though the companies reported a “favorable trend.”

The benefit appeared after the vaccination course was complete. In the first six months, outcomes in the two groups were comparable, but in a pre-specified analysis from six months onward the combination reduced the risk of recurrence or death by 58%. No new safety signals were observed, and the companies said they are engaging with regulators.

Leak forces early release

The results had been scheduled for a presidential symposium at the European Society for Medical Oncology congress in Madrid on Saturday and have been accepted by The New England Journal of Medicine. The companies released them early after partial data leaked on an oncology website Thursday.

Despite the positive findings, Moderna’s stock had its steepest one-day percentage fall on record, sliding as much as 25% and wiping out about $24 billion in market value, according to Reuters. The shares had risen more than 500% this year on expectations for the vaccine. Analysts at UBS and William Blair called the data solid and described the drop as a “sell-the-news” reaction. Merck shares slipped about 1.8%.