Cancer patients who got a COVID vaccine lived much longer

Scientists from the University of Florida and the University of Texas MD Anderson Cancer Center describe this as a milestone in more than a decade of work developing mRNA-based treatments that activate the body's immune defenses against cancer. Building on an earlier UF study, the results represent an important step toward creating a universal cancer vaccine capable of enhancing the effects of immunotherapy.

The analysis, which examined medical records from over 1,000 MD Anderson patients, is still preliminary. However, if upcoming randomized clinical trials confirm these results, the impact on cancer care could be profound.

"The implications are extraordinary -- this could revolutionize the entire field of oncologic care," said senior researcher Elias Sayour, M.D., Ph.D., a UF Health pediatric oncologist and the Stop Children's Cancer/Bonnie R. Freeman Professor for Pediatric Oncology Research. "We could design an even better nonspecific vaccine to mobilize and reset the immune response, in a way that could essentially be a universal, off-the-shelf cancer vaccine for all cancer patients."

Jeff Coller, Ph.D., a leading mRNA expert at Johns Hopkins University, noted that the findings highlight yet another way Operation Warp Speed (the U.S. government's rapid COVID-19 vaccine initiative) continues to benefit lives in "unique and unexpected ways."

"The results from this study demonstrate how powerful mRNA medicines truly are and that they are revolutionizing our treatment of cancer," Coller said.

Presented today (October 19) at the 2025 European Society for Medical Oncology Congress in Berlin, the study builds on eight years of Sayour's research combining lipid nanoparticles with mRNA. Messenger RNA, or mRNA, is present in every cell and carries the instructions for making proteins.

In July, Sayour's laboratory made an unexpected discovery: to trigger a strong immune attack on cancer, it was not necessary to target a specific tumor protein. Instead, they could simply stimulate the immune system to respond as if it were fighting a viral infection.

By pairing their experimental "nonspecific" mRNA vaccine with immune checkpoint inhibitors -- common cancer drugs that help the immune system recognize and destroy tumors -- the researchers observed a powerful antitumor response in mice. This experimental vaccine was not specific to COVID or any other virus or cancer but used similar technology to COVID-19 vaccines.

That breakthrough inspired former UF researcher and current MD Anderson scientist Adam Grippin, M.D., Ph.D., to ask a key question: Could the COVID-19 mRNA vaccine have a similar immune-boosting effect in cancer patients?

To explore that idea, the team analyzed data from patients with Stage 3 and 4 non-small cell lung cancer and metastatic melanoma treated at MD Anderson between 2019 and 2023.

Their findings showed that patients who received a COVID mRNA vaccine within 100 days of starting immunotherapy survived significantly longer than those who did not.

According to Sayour, the most striking improvements occurred in patients who, based on tumor biology and other factors, were not expected to respond strongly to immunotherapy.

Although these results are from an observational study and require confirmation through a randomized clinical trial, researchers emphasize their potential importance.

Despite the need for further validation, Sayour described the discovery as pivotal for the future of cancer treatment.

"Although not yet proven to be causal, this is the type of treatment benefit that we strive for and hope to see with therapeutic interventions -- but rarely do," said Duane Mitchell, M.D., Ph.D., Grippin's doctoral mentor and director of the UF Clinical and Translational Science Institute. "I think the urgency and importance of doing the confirmatory work can't be overstated."

In lung and skin cancers, doctors commonly engage the immune system with drugs designed to "release the brakes" and recognize and attack cancer cells more effectively. In advanced disease stages, however, most patients don't respond well and often have exhausted other treatment options like radiation, surgery and chemotherapy.

The new study involved records of 180 advanced lung cancer patients who received a COVID vaccine within a 100-day period before or after starting immunotherapy drugs and 704 treated with the same drugs who did not receive the vaccine. Getting the vaccine was associated with a near doubling of median survival, from 20.6 months to 37.3 months.

Of the metastatic melanoma patients, 43 received a vaccine within 100 days of initiating immunotherapy, while 167 patients did not receive a vaccine. With the vaccine, median survival increased from 26.7 months to a range of 30 to 40 months; at the time the data were collected, some patients were still alive, meaning the vaccine effect could be even stronger.

Receiving non-mRNA pneumonia or flu vaccines resulted in no changes in longevity.

To back their findings, UF researchers then used mouse models to pair immunotherapy drugs with an mRNA vaccine targeted specifically at COVID spike protein. Those experiments showed they could turn unresponsive cancers into responsive ones, thwarting tumor growth.

"One of the mechanisms for how this works is when you give an mRNA vaccine, that acts as a flare that starts moving all of these immune cells from bad areas like the tumor to good areas like the lymph nodes," Sayour said.

The next step is to launch a large clinical trial through the UF-led OneFlorida+ Clinical Research Network, a consortium of hospitals, health centers and clinics in Florida, Alabama, Georgia, Arkansas, California and Minnesota.

"One of our key motivations at OneFlorida is to move discoveries from academic settings out into the real world and the places where patients get care," said Betsy Shenkman, Ph.D., who leads the consortium.

If confirmed, the new findings unlock numerous possibilities, and the researchers said an even better nonspecific universal vaccine could be designed. For patients with advanced cancers, the increased survival from such a universal vaccine could provide a priceless benefit: more time.

"If this can double what we're achieving currently, or even incrementally -- 5%, 10% -- that means a lot to those patients, especially if this can be leveraged across different cancers for different patients," said Sayour, an investigator with UF's McKnight Brain Institute.

The study was funded by the National Cancer Institute and multiple foundations.

Sayour, Grippin and Mitchell hold patents related to UF-developed mRNA vaccines that are licensed by iOncologi Inc., a biotech company born as a "spinout" from UF in which Mitchell holds interest.