Oct. 20, 2022

It's increasingly clear that the future of cancer care includes highly individualized treatment options. From emerging immunotherapies to next-generation genetic sequencing, learning more about each patient's unique tumor makeup has provided a host of personalized, effective treatment options.

Researchers at Mayo Clinic are maximizing the body's own immune response with advancements in the areas of cancer vaccines.

"We know that human cancers are widely different," says Keith L. Knutson, Ph.D., a cancer vaccine researcher focused on breast and ovarian cancers at Mayo Clinic Comprehensive Cancer Center in Jacksonville, Florida. "We can target multiple antigens, and some of those do overlap. Our challenge is in developing vaccines across the notable differences among varying cancer types."

Much progress has been made in preventing cancer by vaccinating against cancer-causing infections such as HPV and hepatitis B. Dr. Knutson and his colleagues, however, are taking the concept further by developing vaccinations specifically targeting cancerous cells.

Vaccinating across the cancer journey

Dr. Knutson explains that there are three main uses of vaccines in treating and preventing cancer, with various stages of active research across each use.

Vaccines can be applied alongside other treatment strategies to help treat a patient's cancer. A few such vaccines exist, and one is approved by the Food and Drug Administration for patients with prostate cancer. In many cases, these vaccines are used alongside an immunotherapy to maximize the overall therapeutic effect.

Cancer vaccines also can be used to prevent cancer in both a primary and secondary manner. Research on using vaccines for secondary prevention in patients with early-stage disease that has not yet distantly metastasized is underway. Following some form of therapy to bring the cancer into remission, researchers aim to use vaccines to build up a patient's immunity to cancer, therefore preventing recurrence.

Researchers also are studying how cancer vaccines might be used as a primary prevention strategy. In this method, a patient's genetic predisposition will play a central role. Once a predisposition is recognized, the vaccine aims to stimulate the patient's immune response to prevent cancer before it emerges. Primary prevention using cancer vaccines is designed much like vaccinations for infectious disease.

"We have research activity in all three of these areas," says Dr. Knutson. "While cancer vaccines are still in a mostly investigational stage, we are making real advancements toward clinically relevant vaccines."

The future of cancer vaccination

Cancer vaccines are in varying stages of research from treatment through both primary and secondary prevention. In Dr. Knutson's research, the most active advancements are happening in secondary prevention of breast cancer. This research currently includes phase 1 and phase 2 trials funded by the U.S. Department of Defense and the National Cancer Institute (NCI).

Dr. Knutson and his colleagues also have very active research around primary prevention of breast cancer using a vaccine. In collaboration with the NCI and the National Breast Cancer Coalition, this research is expected to move into clinical trials in the next couple of years.

"Sometimes cancer recurs in patients right away, and sometimes recurrence happens after several years," says Dr. Knutson. "It can take quite a lot of time to follow the patients we have on trial."

In most early phase 2 trials, results are evaluated against the relapse rates of a historical control group and statistically analyzed to illustrate the impact of the vaccine.

Using vaccines to treat cancer can be a little easier to evaluate because the impact on the tumor can be seen visually and monitored using advanced imaging tools. Broadly, cancer vaccines are showing promise as a therapeutic option for several cancer types. With the advent of modern genetic sequencing and other genomic technologies, personalized vaccines based on a patient's genetic makeup and the genetic makeup of the tumor involved are on the horizon.

For more information

Refer a patient to Mayo Clinic.