A landmark phase 3 clinical trial presented at the European Society for Medical Oncology Congress shows a personalized mRNA cancer vaccine reduces melanoma recurrence or death by 42 percent. Developed by Moderna and Merck, the treatment was tested alongside Keytruda in over 1,100 post-surgery patients across 157 international sites, marking a major breakthrough in targeted cancer therapy.
How does the personalized treatment work?
The personalized mRNA cancer vaccine works by sequencing a patient's surgically removed tumor to identify its distinct genetic fingerprint. Scientists then design an individualized mRNA sequence that instructs the patient's own immune system to spot and destroy remaining malignant cells. When administered alongside the immunotherapy drug Keytruda, this targeted profile prevents cancer cells from hiding from normal immune defenses, sharply lowering recurrence risks.
Global trial results and regulatory steps
Global study lead Georgina Long described the trial as a foundational shift in oncology, noting that individual neoantigen therapy could transform future cancer care. The phase 3 trial demonstrated sustained protection, with earlier phase data showing even greater risk reductions over time. While the treatment is not yet publicly available, the therapy has entered formal regulatory review in both the United States and Australia.
