Aromasin Approved to Treat Breast Cancer

The FDA recently approved Pfizer's Aromasin to treat postmenopausalwomen with estrogen-receptor-positive earlybreast cancer as a part of the 5-year treatment begun withtamoxifen. The FDA based its decision on results of the IntergroupExemestane Study (IES), in which patients whoswitched to Aromasin after 2 to 3 years of tamoxifen therapy,for a total of 5 years, demonstrated a 31% greater protectionfrom cancer recurrence than those who remained on tamoxifenfor the entire 5-year period. This study was published inthe New England Journal of Medicine, and, soon after, theAmerican Society of Clinical Oncologists and the NationalComprehensive Cancer Network revised their treatmentguidelines to promote the use of Aromasin. The IES studyincluded more than 4700 postmenopausal women withestrogen-receptor-positive breast cancer who were followedfor an average of 35 months. Those patients receiving Aromasinhad a significantly reduced occurrence of the cancer,compared with those receiving tamoxifen alone—thisreduced recurrence included fewer local and distance tumorsas well as new tumors in the other breast. Common sideeffects of Aromasin are mild-to-moderate hot flashes, fatigue,and arthralgia/bone pain. Aromasin should not be used inpremenopausal women.

Ms. Farley is a freelance medical writer based in Wakefield, RI.