These findings are preliminary, but if they are validated in a larger, more conclusive clinical trial, the result could be “a new paradigm” for cancer care, says study coauthor Elias Sayour, MD, PhD, an associate professor of neurosurgery and the principal investigator of the RNA Engineering Laboratory at University of Florida College of Medicine in Gainesville.
“This is really exciting,” says Tanya Evans, MD, a dermatologist and the medical director of the skin cancer program at the melanoma clinic at MemorialCare Saddleback Medical Center in Laguna Hills, California, who was not involved in the research.
How Much Longer Did People Live?
Researchers analyzed records from more than 1,000 patients with advanced lung or skin cancer who were receiving immunotherapy at the University of Texas MD Anderson Cancer Center in Houston. In basic terms, immunotherapy medications work by teaching a patient’s immune system how to recognize and attack cancer cells.
The analysis of lung cancer patients compared two groups: a group of 180 people with advanced lung cancer who received a COVID-19 mRNA vaccine within 100 days of starting immunotherapy, and a group of 704 patients who received the same immunotherapy drugs but didn’t get the vaccine.
The researchers discovered that people with advanced lung cancer who received the vaccine nearly doubled their survival time, from 20.6 months (on average) to 37.3 months.
In patients with advanced melanoma, the most deadly form of skin cancer, 43 received the COVID-19 vaccine within 100 days of starting immunotherapy, while 167 did not get the vaccine. The researchers discovered that those who received the vaccine saw their survival time increase from 26.7 months to up to 40 months. Some melanoma patients were still alive when researchers collected the data, which suggests the impact of the vaccine could be even greater.
“These findings are important because they suggest that widely available mRNA vaccines designed to target COVID-19 might help patients’ immune systems kill their cancer,” says Adam Grippin, MD, PhD, the lead study author and a senior resident in radiation oncology at the University of Texas MD Anderson Cancer Center.
How Do mRNA Vaccines Work?
It’s important to note that, when researchers looked back at the medical records, they observed no changes in survival times when patients received pneumonia or flu vaccines, which are not mRNA vaccines.
That suggests there is something special about mRNA vaccines, says Nilesh Vora, MD, a medical oncologist and the medical director of the Todd Cancer Institute at Long Beach Medical Center in Long Beach, California.
Why Does Vaccination Help Cancer Patients Live Longer?
Scientists are still investigating why COVID-19 mRNA vaccines might fight cancer. But there is a theory. “The mRNA vaccines increase the likelihood of conventional immunotherapy working,” Dr. Sayour says. “This is through the release of cellular alarms that mobilize immune cells to recognize the tumor as foreign.”
Dr. Vora calls this response an “enhancement” of the body’s immune system. “When you give immunotherapy for lung cancer on top of that, you get even more of a response,” he says.
Dr. Grippin describes the mRNA COVID-19 vaccine as a “siren” that activates the immune system and empowers it to kill cancer cells. “Tumor cells counter this immune attack by expressing [making] ‘immune checkpoints’ — proteins that turn off the immune system,” he says. “When we combine mRNA vaccines with immune checkpoint inhibitors, we block these proteins and unleash the power of the immune system to kill cancer.”
Dr. Evans expands on that idea. “In a sense, the vaccine expands the tumor cells and the immune therapy keeps it going for a stronger reaction,” she says. “This is great news for melanoma and lung cancer, as well as other cancers.”
Why the Findings Matter
This study was focused on patients with certain types of cancer who used the mRNA COVID-19 vaccine, but oncologists say the findings have even bigger implications. “This adds fuel to the thought that the immune system plays a tremendous role in cancer outcomes,” Vora says. “It seems that an mRNA vaccine given around the same time as immunotherapy can enhance immune response.”
The results also support the development of universal cancer vaccines to “wake up” the immune system before people undergo immunotherapy, Sayour says.
Additionally, the findings suggest that future mRNA vaccines could be tailored to target specific cancers, Evans says. “Instead of presenting instructions to make a spike protein, you can make instructions to make antigens to the cancer,” she explains. (Antigens are any substance that provokes the immune system to make antibodies.) “Then, the body can make antibodies that attack the cancer directly.”
What Happens Next?
The study was observational (meaning researchers looked back at existing data not initially collected for this purpose) and will require a randomized, controlled trial to see if the findings can be replicated. But the research team is already planning a phase 3 clinical trial that is expected to start before the end of the year.
“Our hope is that RNA therapeutics could not only help patients who are already planning to receive immune therapy, but also extend the benefits of immune therapy to patients with immune-resistant tumors,” Grippin says.
Ultimately, Vora says this is a big step in the right direction. “This is very exciting,” he says.
