An experimental personalized cancer vaccine developed by Merck and Moderna delivered positive results in its first late-stage trial, bringing the companies closer to potential regulatory submissions for the treatment. The mRNA-based vaccine, used alongside Merck’s Keytruda immunotherapy, met key goals in a Phase 3 trial involving more than 1,100 patients with higher-risk or advanced melanoma.
The treatment combination significantly extended the time patients lived without their melanoma returning compared with Keytruda alone and also reduced the risk of the cancer spreading to distant parts of the body. The results build on earlier Phase 2 data for the same treatment approach.
Investors reacted strongly to the announcement, with Merck shares rising more than 12% and Moderna shares surging about 177%. The move reflected the companies’ different market sizes, with Merck entering the session with a market capitalization of around $333 billion and Moderna at approximately $25 billion.
A New Personalized Approach to Cancer Treatment
The vaccine is designed to target the unique mutations found in each patient’s tumor rather than using a one-size-fits-all approach. By training the immune system to recognize specific cancer markers and combining that response with Keytruda, researchers aim to help the body attack cancer more effectively.
The Phase 3 trial will continue evaluating additional outcomes, including overall survival benefits. Merck and Moderna plan to present the data at an upcoming international medical meeting, while discussions with regulatory agencies are expected to begin in the coming months.
The companies are also studying the personalized vaccine approach across additional cancers, including non-small cell lung cancer, bladder cancer and renal cell carcinoma.
