Orteronel as Monotherapy in Patients With Metastatic Breast Cancer (MBC) That Expresses the Androgen Receptor (AR)

The androgen receptor (AR) is expressed in 70-90 percent of primary breast tumors and in 75 percent of breast metastases. There is evidence to suggest that Androgen Receptor (AR) may be a target in patients with advanced breast cancer. Breast cancer patients whose tumors do not express the ER, PR or HER2 (triple negative) have very few options for treatment. Orteronel is being developed as an endocrine therapy for relevant hormone-sensitive cancers such as prostrate cancer and breast cancer. Triple-negative metastatic breast cancer patients with AR expression could potentially benefit from anti-androgen therapy like orteronel.