Merck and Moderna Announce Promising Phase 3 Results for Personalized mRNA Cancer Vaccine
Merck and Moderna reveal positive Phase 3 trial outcomes for a personalized mRNA vaccine that lowers melanoma recurrence and metastasis risk.
By John Mtongoi Newsroom
August 19, 2026
2 min read
US pharmaceutical giants Merck and Moderna have unveiled encouraging Phase 3 trial results for intismeran autogene, a personalized mRNA cancer vaccine targeting melanoma.
The vaccine was tested in combination with Merck's immunotherapy drug Keytruda among 1,137 patients diagnosed with stage IIB to IV melanoma. Participants were randomly assigned to receive either the vaccine plus Keytruda or Keytruda alone.
Trial Outcomes
- The combination therapy significantly reduced the risk of melanoma recurrence after surgical removal.
- It also lowered the chance of the cancer spreading to other parts of the body.
- No new safety concerns were reported compared to earlier studies.
The vaccine is tailored to each patient by identifying unique genetic mutations in their tumor, enabling the immune system to specifically target cancer cells carrying those mutations.
Future Prospects
Moderna's president, Stephen Hoge, indicated that if regulatory approvals are granted, the treatment could be available as soon as next year. The companies plan to present full trial data at an upcoming medical conference and are engaged in discussions with regulators.
Beyond melanoma, Merck and Moderna are exploring the use of personalized mRNA vaccines for other cancers including lung, kidney, and bladder cancers.
Context
Melanoma remains a deadly skin cancer globally, with over 330,000 new cases reported in 2022 according to the World Health Organization. This breakthrough marks the first positive late-stage trial for an mRNA-based cancer vaccine, representing a significant advancement in personalized cancer treatment.
