Positive Study Results for Potential Breast and Ovarian Cancer Vaccine

Researchers have reported that PANVAC, a potential breast and ovarian cancer vaccine, has shown promise in a small-scale study, as it elongated the overall survival time in some patients. In fact, researchers found that the progression of the cancer was halted in some breast cancer patients.

Researchers from the National Cancer Institute studied the effects of the vaccine on 26 patients, all of whom were diagnosed with either breast cancer or ovarian cancer that had spread to other organs. All participants had already been pretreated. Of the 26 patients, 21 of them had previously received at least three chemotherapy regimens. The participants were given monthly vaccinations of PANVAC. The potential vaccine works by attempting to train the body to attack tumor cells; it contains transgenes for MUC-1, CEA, and three T cell costimulatory molecules.

Of the 12 breast cancer patients, the median time to progression was 2.5 months. The median overall survival was 13.7 months. Four of the patients had stable disease. Of the 14 patients with ovarian cancer, the median time to progression was two months. The median overall survival was 15 months.

The researchers reported that the side effects of the vaccine were rather mild and consisted for the most part of reactions at the area of injection. "With this vaccine, we can clearly generate immune responses that lead to clinical responses in some patients," reported lead researcher James Gulley, MD, PhD, director and deputy chief of the clinical trials group at the Laboratory of Tumor Immunology and Biology at the National Cancer Institute.

Gulley went on to state that attention paid to cancer vaccines is increasing, and more studies are necessary in order to find out which vaccines will benefit certain patients. "The sustained benefit seen in some patients in this study underscores the potential for therapeutic vaccines to impact clinical outcomes without toxicity," he stated. "However, more studies in the appropriate patient populations are required to adequately assess efficacy."