Patients with advanced non-small cell lung cancer and metastatic melanoma lived longer when they received a COVID-19 mRNA vaccine within 100 days of starting immune-checkpoint therapy, according to researchers from MD Anderson Cancer Center and the University of Florida. The retrospective analysis of more than 1,000 patient records found median survival nearly doubled for vaccinated lung cancer patients (37.3 months vs 20.6 months).
The work, published in Nature in October 2025 and presented around the ESMO 2025 congress, suggests standard COVID mRNA vaccines may “prime” the immune system to help checkpoint inhibitors work better. Scientists say the effect appears specific to mRNA technology; flu and pneumonia vaccines did not show similar benefits in the dataset.
Implications and Next Steps
Experts emphasize that these are observational, retrospective results requiring prospective validation. “This general immune signal might be very important in helping our immune therapies work better,” said Dr. Joshua Veatch of Fred Hutchinson Cancer Center, an independent commentator. He highlighted the need to optimize timing and dosing in future trials.
king5.comThe benefits were especially pronounced in “cold” tumors with low PD-L1, where three-year survival improved nearly fivefold. If confirmed, off-the-shelf mRNA COVID vaccines could offer a low-cost, widely available boost to immunotherapy response rates across cancers—potentially transforming standard care.
Response and Ongoing Research
MD Anderson researchers have initiated planning for a multicenter, randomized Phase III trial to test whether timed mRNA COVID vaccination should become routine alongside checkpoint therapy. Coverage in Nature, Reuters, and Medscape echoes the promise but stresses caution until randomized data confirm causality and safety.
