Vaccines for Cancer? Scientists Are Making Progress

In Furneaux’s case, researchers biopsied the tumors in his lungs and genetically sequenced his cancer cells. Then they formulated a vaccine that targeted his unique tumor protein mutations.  

Furneaux got two injections at each of four appointments in fall 2021. He also received immunotherapy — the standard treatment for his type of melanoma that helps the immune system fight it.

Now, almost two years later, Furneaux says his cancer has not only not progressed, it has actually receded.

Data from another vaccine being tested for the treatment of melanoma produced similarly promising results.

In an intermediate-stage study, Moderna and Merck released data showing that their mRNA melanoma cancer vaccine, when paired with Merck’s immunotherapy treatment, reduced the risk of cancer recurrence or death by more than 44 percent compared to immunotherapy alone.

It was the first randomized study showing that a cancer vaccine added to typical treatment could substantially increase survival. Based on those results, the Food and Drug Administration granted breakthrough designation, a sign that the agency believes the therapy is a significant improvement over existing treatments.

Another promising personalized vaccine that recently made headlines targets pancreatic cancer. In May, researchers at Memorial Sloan Kettering Cancer Center published a study in the journal Nature that showed an mRNA vaccine they had developed with BioNTech prevented a deadly form of pancreatic cancer from returning in about half of trial participants.

Other personalized vaccines in development target different types of cancer including cervical, colorectal, prostate and lung.

“This is all very exciting,” says William Dahut, M.D., chief scientific officer for the American Cancer Society. “The small trials are being transformed into big trials, and if they have positive results, at least in those cancers, I think this could be just a couple of years away.”

Some vaccines target specific subsets of cancers

Other cancer vaccines in the pipeline are designed to work for more than just one patient.

At the University of Washington School of Medicine, for example, researchers are testing a vaccine that targets a protein, called HER2, that is expressed at abnormally high levels in some 30 percent of breast cancers, causing the cancer to grow rapidly.

In a phase 1 study of 66 women with advanced-stage HER2-positive breast cancer, the vaccine elicited a strong immune response, according to published results. And although the study was not designed to test the vaccine’s effectiveness, the researchers noted that the participants did better than would be expected for having such an advanced stage of the disease.

“If you look at patients at that stage, you would have expected that only half would be alive in five years. But 80 percent of our participants are still alive today,” says Kiran Dhillon, executive director of the UW Cancer Vaccine Institute. “That’s pretty powerful.”

The vaccine institute is now testing new vaccine formulations that target multiple proteins instead of just one, Dhillon says, as well as vaccines for ovarian cancer, lung cancer, prostate cancer, bladder cancer and colon cancer.

The holy grail: More preventive cancer vaccines

While much of the momentum has been on vaccines for people who have already have cancer, scientists are still working to develop more vaccines that can effectively prevent cancer.  

Take, for instance, New York’s Weill Cornell Medicine, which received a $5.7 million federal grant to work on preventive cancer vaccines in 2022.

Steven Lipkin, M.D., a medical geneticist who is leading the effort, says the team is focusing first on developing vaccines for at-risk groups, such as people with inherited genetic mutations that predispose them to certain cancers.

The vaccines target common mutations shared by individuals in those groups who develop cancer. For example, his center is developing a vaccine for people with Lynch syndrome, a genetic condition that greatly increases the risk of developing colon and other cancers before the age of 50. The vaccine targets common proteins that often appear on tumors in patients who have the syndrome.  

The center is also working to develop preventive vaccines for children who have a rare genetic condition that predisposes them to cancer and for patients who develop precancerous lung lesions that increase their risk of lung cancer.

Focusing on those high-risk groups will allow the team to know sooner how effective a vaccine is at preventing a tumor, he says.

“It’s a practical thing — we want to run trials and be able to do it quickly, within a few years,” Lipkin says. “It gives us a chance to see if the vaccine can intervene and slow it down or get rid of it.”

The good news, he says, is that the risk of dying from cancer in the United States is down about 27 percent in the last 20 years, but “the next thing to really move the needle in a meaningful way is vaccines.

“We’re hopeful that this is really going to make meaningful progress against cancer in the next decade or so,” Lipkin says. “Prevention is really the best cure for cancer.”