Breast Cancer Vaccine Boosts Immune Response, Slows Disease Progression in Small Study
Although the study was small, the findings suggest that the vaccine may also boost a patient's immune response and help slow disease progression. "I don't want to oversell this," cautioned study coauthor William Gillanders, MD, of the Washington University School of Medicine in St. Louis. "This is a small clinical trial. But we can say confidently that the vaccine was safe," he told HealthDay. "We can also say with confidence that we were able to generate an immune response in almost all the patients who were vaccinated," he added. "And there is preliminary evidence that the vaccine may have an impact on breast cancer progression. But that needs to be studied further to be confirmed."
Fourteen women with advanced breast cancer were injected with a vaccine that targets the protein mammaglobin-A, found in high amounts in breast tumors. The study authors noted that overexpression of mammaglobin-A is found in up to 80% of breast cancer patients. The vaccine prompts CD8 T-cells to track and eliminate the protein. The team found that side effects from the vaccine after one year were minimal, and included rashes, tenderness, and mild flu-like symptoms. By the one-year mark roughly 50% of the patients showed no sign of disease progression. By comparison, only 20% of a similar group of 12 patients showed no signs of disease progression one year out.
Even though the researchers stressed the need for a larger, longer study, they theorized that if the vaccine were given to newly diagnosed breast cancer patients who had not yet been exposed to chemotherapy, the vaccine might prove even more effective at halting disease. "This trial wasn't really designed to look at this question, which makes it difficult to interpret the results so far," Gillanders noted. "But there's been a lot of interest in the development of a prevention vaccine for breast cancer and other cancers. And this work confirms the promise of such a strategy."