NIH -- New research indicates that giving patients a continuous low dose of an immune system booster, a method known as metronomic dosing, as part of a therapeutic prostate cancer vaccine strategy is safe and produces similar immune responses and fewer side effects than the more common dosing method, which is not well tolerated by many patients. This study, led by researchers at that National Cancer Institute (NCI), part of the National Institutes of Health, was published in the Aug. 15, 2008, issue of Clinical Cancer Research.