New Drug for Triple Negative Breast Cancer in Clinical Trials
A new drug dubbed BSI-201 is the subject of a major clinical trial as a potential treatment for triple negative breast cancer. Approximately 15 percent of breast cancer cases are the triple negative form, a type that does not respond to traditional breast cancer drug treatment.
Triple negative breast cancer is hard to treat
The term “breast cancer” refers to not one type of cancer but to many different subtypes of the disease. These subtypes are usually diagnosed based upon the presence (or lack) of three receptors that are known to fuel and promote most breast cancers: estrogen receptors, progesterone receptors, and human epidermal growth factor receptor 2 (HER2).
Breast cancer treatments that are most successful target these receptors, according to the Triple Negative Breast Cancer Foundation. Women who have triple negative breast cancer, however, do not have any of these three receptors, which means these women generally do not respond to treatments proven to be effective, including tamoxifen and Herceptin.
Depending on the stage of disease at diagnosis, triple negative breast cancer can be very aggressive, and it is more likely to recur than other subtypes of breast cancer. The good news is that women who have the triple negative form do respond to chemotherapy.
Now a new drug specifically for treatment of triple negative breast cancer is being tested in a clinical trial in the United States, according to the UK Telegraph. Results from previous lab studies and early trials indicate that BSI-201 can be effective when used along with other chemotherapy drugs.
Women who have triple negative breast cancer have defects in BRCA1 and BRCA2, two genes that have a major role in repairing DNA in cells. Scientists discovered that cells with these defects are especially sensitive to breast cancer treatments called poly-ADP-ribose polymerase (PARP) inhibitors. BSI-201 is such a drug and has been shown to cause the death of cancer cells that have these defective genes.
In phase II trials, BSI-201, when used with other chemotherapy drugs, helped to reduce tumors. Sixty-two percent of women who were given BSI-201 along with chemotherapy had clinical benefits compared to only 21 percent who were given chemotherapy alone. Overall survival among women who received both BSI-201 and chemotherapy increased from 5.7 months to 9.2 months when compared to women who received chemotherapy alone.
Women who have triple negative breast cancer may eventually have access to a new drug to fight this less common form of the disease. For more information about this form of breast cancer, you can access the Guide to Understanding Triple Negative Breast Cancer online. The guide was created as a partnership between the Triple Negative Breast Cancer Foundation and Living Beyond Breast Cancer.
Triple Negative Breast Cancer Foundation