ER+ Breast Cancer

Estrogen Receptor-positive (ER+) breast cancer accounts for nearly three-quarters of the more than 2 million cases of breast cancer each year in the US.1,2

Hormonal therapy is a mainstay of treatment but is associated with side effects; nearly one-third of patients discontinue hormonal therapy because of toxicity.3

More than half of cases will relapse on therapy and the 5-year survival rate for metastatic ER+ breast cancer is only 27%, highlighting the significant need for effective therapies.4


1. United States Census Bureau. 2. American Cancer Society® Breast Cancer Facts & Figures 2019-2020. 3. Berkowitz MJ, et al.. J Cancer Surviv. Published online August 17, 2020. doi:10.1007/s11764-020-00908-5. 4. Rozeboom B, et al. Am J Cancer Res. 2009; 9(12):2821-2831.