Researchers at the Cleveland Clinic in the United States launched a new vaccine study aimed at eventually preventing triple negative breast cancer, a highly invasive and deadly form of cancer. The vaccine has the potential to become the first vaccine ever to prevent breast cancer.
The phase I clinical trial aims to determine the maximum tolerated dose of the vaccine in patients with early triple negative breast cancer and to characterize and optimize the immune response of the body. The US Food and Drug Administration (FDA) recently approved an application for a new research drug for the vaccine.
Dr G.Thomas Budd, lead researcher at the Cleveland Clinic’s Taussig Cancer Institute, said “we hope that this study will lead to more advanced trials to determine the effectiveness of the vaccine against this highly invasive breast cancer. In the long run, we hope this will become a real preventive vaccine for healthy women to prevent them from developing triple negative breast cancer. At present, we have the worst treatment for this kind of cancer.
Triple negative breast cancer does not have the biological characteristics that usually respond to hormone or targeted therapy, so there is an urgent need to improve its treatment. Although it accounts for only 12-15% of all breast cancer, it has a higher proportion of breast cancer deaths and a higher recurrence rate. About 70% to 80% of breast cancer patients with BRCA1 mutations are triple negative.
“This vaccine represents a potential way to control breast cancer,” said Dr. Vincent Tuohy, an immunologist at the Cleveland Clinic’s Lerner Institute and the lead developer of the breast cancer vaccine. “The long-term goal is to determine whether the vaccine can prevent breast cancer before it occurs, especially for the more aggressive triple negative breast cancer.”
The vaccine targets breast-specific lactation protein (α-whey protein), which no longer exists in normal aging tissues after lactation, but exists in most triple negative breast cancers. Activating the immune system against this “retired” protein provides pre-emptive immune protection against breast tumors that express α-whey protein. The vaccine also contains an adjuvant that activates an innate immune response that causes the immune system to respond to emerging tumors and prevent them from growing.
The new study is based on a previous preclinical study led by Tuohy, which showed that activating the immune system targeting α-whey protein is safe and effective in preventing breast tumor in mice. The study also found that a single vaccination can prevent breast tumors in mouse models and inhibit the growth of existing breast tumor.
This new study will involve 18 to 24 patients who have completed early triple negative breast cancer treatment in the past three years and are currently tumor-free but at high risk of recurrence. In process, subjects will receive three vaccinations at intervals of two weeks, and the researchers will closely monitor side effects and immune responses. The study is expected to be completed in September 2022.
The researchers expect a subsequent trial to recruit healthy, cancer-free women at high risk of breast cancer who decide to voluntarily undergo bilateral mastectomy to reduce their risk. Usually, these women carry mutations in the BRCA1 or BRCA2 gene and therefore have a higher risk of developing triple negative breast cancer or other forms of breast cancer.
“This vaccine strategy has the potential to be applied to other types of tumors,” Tuohy added. “Our transformation research program focuses on vaccine development to prevent diseases we face with age, such as breast, ovarian, and endometrial cancer. If successful, the vaccine has the potential to change the way we control cancer in adults and increase life expectancy in a manner similar to that of children.”