Haverhill Financial Research · News · Biotech · October 23, 2026
What happened
Moderna and Merck presented Phase 3 results for intismeran autogene, a personalized mRNA cancer vaccine, in the Presidential Symposium at the ESMO 2026 congress. The study, INTerpath-001, enrolled 1,137 patients with high-risk melanoma that had been removed by surgery. Adding the vaccine to Keytruda reduced the risk of the cancer returning, or of death, by 42% compared with Keytruda alone. The results were also published in the New England Journal of Medicine.
Share of patients, two-year estimates. Source: Merck and Moderna, October 22, 2026.
The numbers
| Measure | Vaccine + Keytruda | Keytruda alone | Hazard ratio |
|---|---|---|---|
| Recurrence-free survival, two years | 82.2% | 70.0% | 0.58 |
| Distant metastasis-free survival, two years | 88.5% | 80.2% | 0.62 |
| Grade 3 to 5 adverse eventsShare of patients | 14.2% | 13.4% | — |
Two details matter. The curves did not separate in the first six months (hazard ratio 0.99), which fits a vaccine that takes time to train the immune system. And serious side effects were only slightly more common with the combination, 14.2% against 13.4%. Overall survival data are not yet mature.
Why it matters
This is among the first Phase 3 results for an individualized mRNA cancer treatment, and it comes from a large, randomized trial rather than an early study. For Moderna, whose revenue has fallen sharply since the pandemic, it is the clearest evidence so far that its technology can work outside infectious disease.
What comes next
We would watch for three things: regulatory filings, the overall survival readout once the data mature, and results in the other cancers where the vaccine is being tested.
Sources and disclosures
Details come from the Merck and Moderna announcement of October 22, 2026.
Disclosures. Haverhill Financial Research is a publisher of general financial commentary. This article is not personalized investment advice and does not consider any reader's financial situation; readers should do their own research. Nothing here is a recommendation to buy or sell any security. Company figures and guidance can change. The author of this post does not hold positions in Moderna or the other companies named. Data as of October 23, 2026.
