New Vaccine Shows Promise for Treating Prostate Cancer Patients

Layne Lowery

A new method for administering a prostate cancer vaccine may provide a safe—and possibly more effective—treatment for prostate disease.

A study led by researchers at the National Institutes of Health’s National Cancer Institute (NCI) found the method known as metronomic dosing provides continuous low doses of an immune system booster.

According to an NCI statement, this dosing method could decrease the side effects associated with other prostate disease treatments.

Cancer vaccines help your immune system attack tumor cells without harming normal cells. The vaccine in this study is designed to trigger this response against prostate-specific antigen (PSA). This protein often occurs at higher levels in men who have prostate cancer and some non-cancerous prostate conditions.

The NCI researchers studied the side effects and immune responses of patients treated with a three-pronged approach: the vaccine, radiation therapy and doses of the immune system booster—interleukin-2 (IL-2).

IL-2 can boost your body’s natural defenses; but it often produces side effects such as fatigue and high blood sugar. As a result, patients often reduce the amount of IL-2 they take—or stop taking it altogether.

The researchers’ goal was to decrease the side effects associated with IL-2. They administered the same total amount of IL-2 as used in traditional prostate cancer treatment—but in smaller daily doses over a longer period of time.

The results? Fewer than a quarter of the patients had side effects that required their dose of IL-2 to be reduced!

“Developing an alternative method of administering vaccine therapy that is well tolerated by most patients and produces similar immune responses to standard methods may help further the development of vaccine therapies for prostate cancer,” said James L. Gulley, M.D., Ph.D., of NCI’s Center for Cancer Research.

Gulley said the new dosing method appears to be a superior way to treat prostate cancer.