COVID-19 vaccines, credited with saving millions of lives during the pandemic, set off a powerful alarm that rallies the human immune system against cancer and nearly doubles the median survival length of patients, according to a new retrospective study by researchers at the University of Texas MD Anderson Cancer Center and the University of Florida.
The study examined the records of more than 1,000 MD Anderson patients who had already started approved immunotherapy for advanced non-small-cell lung cancer and melanoma, a type of skin cancer, comparing those who received coronavirus mRNA vaccines with those who had not.
“This data is incredibly exciting, but it needs to be confirmed in a Phase III clinical trial,” said Adam Grippin, lead author of the study published Wednesday in the journal Nature.
Grippin, who worked on the project while at the University of Florida and is now a radiation oncologist at MD Anderson, said planning for a Phase III clinical trial is underway and organizers hope to begin enrolling patients by the end of the year.
While the findings raise hope that scientists may be able to develop a universal, off-the-shelf vaccine for patients with different cancers, they come at a difficult time for research into vaccines that use messenger RNA.
In August, Health and Human Services Secretary Robert F. Kennedy Jr. announced that the U.S. government was ending almost $500 million in mRNA vaccine development, “because the data show these vaccines fail to protect effectively against upper respiratory infections like COVID and flu.” Scientists have vigorously disputed Kennedy’s contention.
Vaccines that use messenger RNA, a single-stranded molecule, instruct our immune system without actually infecting the body, teaching cells to make a harmless piece of virus protein. Under President Donald Trump’s Operation Warp Speed program to fight the COVID-19 pandemic, scientists were able to use the mRNA platform to develop vaccines less than a year after the virus was detected. Vaccine development often takes 10 to 15 years.
But mRNA vaccines were by no means a new idea. For more than two decades, scientists had been investigating their use against influenza and cancer.
In the latest study, scientists looked back at almost 900 patients with advanced lung cancer treated at MD Anderson and found that those given COVID-19 vaccines within 100 days of starting cancer immunotherapy experienced median survival of 37.3 months compared with 20.6 months for those who were not vaccinated. Patients with melanoma that had spread also showed improved median survival when they were vaccinated.
The immunotherapy — called immune checkpoint treatment — works by releasing a brake that prevents an excessive immune response from killing healthy cells. Releasing that brake allows white blood cells called T cells to attack cancer.
Asked for response to the new study, the Department of Health and Human Services released a statement saying: “The risk-benefit of Covid vaccination in people under age 65 is most favorable for those who are at an increased risk for severe COVID-19, including groups like the advanced cancer patients analyzed in this hypothesis. We terminated 22 mRNA vaccine development investments because the data showed they failed to protect effectively against upper respiratory infections like COVID.”
Precisely why the mRNA vaccines proved so effective in awakening the body’s immune system to the presence of cancer isn’t yet clear, but it may have something to do with RNA’s fundamental role in the evolution of life.
“RNA preceded DNA evolutionarily, so cells don’t like RNA from the outside world coming in,” said Elias Sayour, one of the authors of the new paper and a pediatric oncologist at University of Florida Health. “So when that happens, that sets off all the alarms of the human body. The 911 signals we’re in trouble.”
Grippin had worked in Sayour’s University of Florida lab until 2019; he joined MD Anderson in July 2021.
Scientists at both institutions followed up the examination of the MD Anderson patient records by experimenting in the lab with mouse models, and they found that when immunotherapy treatment was used with mRNA vaccination, the combination slowed tumor growth.
“It is not unexpected. You can expect that more data will come out,” said Katalin Karikó, the University of Pennsylvania researcher who shared the 2023 Nobel Prize in medicine with Drew Weissman for work that led to the development of the coronavirus vaccines.
Kariko, who was not involved in the new study, said that in May she was in Europe speaking with other scientists “and they mentioned that the COVID vaccine has an effect on cancer growth.” There are about 150 clinical trials of mRNA vaccines ongoing around the world, Kariko said, almost half for treatment of infectious diseases and many of the others for cancers.
“People are trying and they can see it is easy. It is cheap and very quickly you can proceed,” she said. “It will advance and it will benefit the patient.”
Jeff Coller, a professor of RNA biology and therapeutics at Johns Hopkins University who was also not involved in the Nature paper, said mRNA has been viewed as a promising cancer treatment because “it’s a natural product of the human body. Your mRNA is made by the body millions of times per day, and it’s incredibly adaptable.”
He added that mRNA “is very easy to work with, develop, manufacture and change as needed. No other medical therapeutic is this adaptable.” As an example, he pointed out that the day after scientists determined the genomic sequence of the virus SARS-CoV-2, researchers were able to design an mRNA vaccine against it, though it took months longer before vaccines were approved and put into use.
Grippin said the path toward the latest discovery began in 2016 when he and other scientists were experimenting with a vaccine specifically tailored for the brain tumors of individual patients.
“We ran an experiment designed to show how important it was that we make a new vaccine” to match the specific makeup of each tumor. The shock came when they examined the response of the control vaccines.
Although the control vaccines were completely unrelated to the tumor’s composition, they showed a remarkable immune response.
“It was the exact opposite of what we had expected to happen,” Grippin said. “But it opened the door to the possibility that we could design a universal vaccine that could be used to train any patient’s immune system to kill their cancer.”
No comments:
Post a Comment