COVID mRNA Shots May Boost Cancer Immunotherapy

A surprising benefit of mRNA COVID-19 vaccines may reach beyond protection from infection. Researchers at MD Anderson Cancer Center found that cancer patients who received an mRNA COVID-19 vaccine shortly before starting immunotherapy lived significantly longer than those who did not.

The retrospective study, now published in Nature and presented at the European Society for Medical Oncology (ESMO) 2025 Congress, analyzed data from more than 1,000 patients with advanced melanoma or lung cancer. Among those treated with checkpoint inhibitors, three-year survival was nearly twice as high in vaccinated patients. Laboratory experiments in mice supported these findings, showing that mRNA vaccination strengthens immune signaling and helps immune cells better recognize and attack tumors.

The COVID-19 vaccines were not designed to target cancer, but their ability to activate type I interferon and other immune pathways appears to “prime” the body for a stronger response to therapy.

The effect was most pronounced in patients whose tumors usually respond poorly to immunotherapy, and similar benefits were not seen with flu vaccination.

If confirmed in upcoming clinical trials, a widely available vaccine could become a low-cost and straightforward way to improve outcomes for people receiving immune-based cancer treatments, while offering new insight into how immune activation and regulation intersect across diseases.

Citations

Jacobs, P. (2025). COVID-19 vaccines may boost cancer immunotherapy. Science (New York, N.Y.), 390(6771), 321–322. https://doi.org/10.1126/science.aed2823

Grippin, A. J., et al. (2025). SARS-CoV-2 mRNA vaccines sensitize tumours to immune checkpoint blockade. Nature, 10.1038/s41586-025-09655-y. Advance online publication. https://doi.org/10.1038/s41586-025-09655-y

European Society for Medical Oncology: Grippin AJ, et al “SARS-CoV-2 mRNA vaccines sensitize tumors to immune checkpoint blockade” ESMO 2025; Abstract LBA54.