Moderna-Merck mRNA melanoma vaccine cuts relapse risk 42% in trial
A personalised mRNA vaccine from Moderna and Merck cut the risk of melanoma relapse or death by 42% in the Interpath-001 phase 3 trial of 1,137 patients.
Livefeed News DeskUpdated · 3 min read
Quick answer
A personalised mRNA cancer vaccine developed by Moderna with Merck cut the risk of relapse or death by 42% in patients with high-risk advanced melanoma. The phase 3 Interpath-001 trial, presented at ESMO in Madrid in late October 2026, enrolled 1,137 patients. After two years, 82% of vaccinated patients were relapse-free, against 70% on standard therapy.
Key facts
- The Interpath-001 trial was presented at the ESMO congress in Madrid in late October 2026.
- 1,137 patients took part in the international phase 3 trial.
- Two-year recurrence-free survival was 82% with the vaccine added, against 70% with standard therapy alone.
- Each dose is made for one patient, based on the mutations in their tumour.
- Separately, the UCPVax telomerase vaccine developed in Besançon is preparing for a phase III trial.
What the trial found
A personalised mRNA cancer vaccine developed by Moderna in partnership with Merck significantly reduced the risk of relapse in patients with high-risk advanced melanoma, according to results of the international Interpath-001 trial. The data were presented at the European Society for Medical Oncology (ESMO) congress in Madrid at the end of October 2026.
The phase 3 study enrolled 1,137 patients. The vaccine was given alongside immunotherapy after surgery. After two years of follow-up, recurrence-free survival was 70% among patients on standard therapy alone and 82% among those who also received the vaccine, which works out to a 42% lower risk of recurrence or death.
Phase 3 is the most rigorous stage of testing before a treatment can be considered for marketing approval, and the source does not report that any approval has been granted.
How a made-to-measure vaccine works
Unlike a conventional vaccine given in the same form to everyone, each dose here is manufactured for a single patient, based on the mutations found in their tumour. The mRNA instructs the patient’s cells to produce proteins specific to that tumour, training the immune system, in particular lymphocytes, to find and destroy cancer cells left behind after surgery.
French science site Futura credited the approach to advances that came out of Covid-19 vaccine research.
What oncologists are saying
Fabrice André, director of research at the Gustave Roussy institute in Villejuif, said the results exceed what oncologists regard as a clinically relevant impact. He described it as the first time the real benefit of a personalised cancer vaccine has been demonstrated, and noted that new kinds of treatment do not come along every day.
In France, around 3,000 to 3,500 new patients a year have the type of advanced melanoma concerned, according to Futura.
A separate French effort: UCPVax
Researchers at the Besançon university hospital have also announced progress on UCPVax, a therapeutic cancer vaccine that is not mRNA-based, according to the Bourgogne-Franche-Comté regional council, which has backed the project. It is given to patients who already have cancer and targets telomerase, an enzyme present in the large majority of cancers, by activating CD4 T cells that help coordinate the immune response.
Professor Olivier Adotevi, who works at the hospital’s regional cancer institute, compared the immune system to an army and said the vaccine stimulates the officers so that they order the soldiers to attack the tumour. UCPVax has been developed over more than ten years by the UMR Right research unit with the French blood service EFS, Université Marie et Louis Pasteur and Inserm.
Phase I and II trials produced promising results, notably in glioblastoma, an aggressive brain cancer. The programme is preparing to launch phase III, which the council said would be a first in France for a therapeutic vaccine targeting telomerase.
Frequently asked questions
What is the Interpath-001 trial?
An international phase 3 trial of a personalised mRNA vaccine from Moderna and Merck in 1,137 patients with high-risk advanced melanoma.
How effective was the mRNA melanoma vaccine?
Added to immunotherapy after surgery, it reduced the risk of recurrence or death by 42%. Two-year recurrence-free survival was 82%, against 70% with standard therapy.
Is the mRNA cancer vaccine personalised?
Yes. Each dose is made for one patient based on the mutations in their tumour.
What is UCPVax?
A therapeutic vaccine developed in Besançon that targets telomerase in patients who already have cancer. It is preparing for a phase III trial.
