Also called Aromasin, a drug used to treat advanced breast cancer and to prevent recurrent breast cancer in postmenopausal women who have already been treated with tamoxifen. It is also being studied in the treatment of other types of cancer. Exemestane causes a decrease in the amount of estrogen made by the body. It is a type of aromatase inhibitor.

The latest studies found the estrogen-blocker Aromasin reduce the risk of developing breast cancer by 65 percent in post-menopausal women at high risk for breast cancer.