San Antonio – The San Antonio Breast Cancer Symposium (Twitter #SABCS14) is underway, and one of the key questions everyone is asking is do checkpoint inhibitors work in Triple Negative Breast Cancer (TNBC)?
TNBC is defined as the absence of estrogen receptor (ER), progesterone receptor (PR) and HER2 protein expression. This means that treatments aimed at these targets such as aromatase inhibitors and Herceptin are unlikely to work in TNBC.
TNBC represents approximately 15% of breast cancer patients in the U.S, and to put this number into perspective, around 200,000 women have the disease, with 40,000 deaths each year. Globally, there are an estimated 1 million cases of breast cancer, of which 170,000 are triple-negative (ER-/PR-/HER2-).
The only currently available treatment for TNBC is chemotherapy, but sadly patients often do not live long, and rapidly progress. Progression-free survival (PFS) is estimated to be around 4 months in TNBC. This means there is a real unmet medical need for effective new treatments.
Checkpoint inhibition of the programmed-death 1 receptor (PD-1) such as pembrolizumab (Merck) and the ligand (PD-L1) e.g. MPDL3280A (Genentech/Roche) can increase the effectiveness of a body’s T cells to fight cancer. Are checkpoint inhibitors the future in TNBC and will they offer hope to patients?
Some early preliminary clinical data is being presented this week at SABCS. Subscribers can login below or you can purchase access to read more about what this data signals about the potential of checkpoint inhibition in TNBC.