United States of America -The manufacturer of conjugated estrogens/medroxyprogesterone acetate (Prempro™) (Premphase®), and conjugated estrogens tablets (Premarin®) has informed health care professionals of new labelling changes. These state that estrogens and estrogens plus progestin therapies should not be used for the prevention of cardiovascular disease. The boxed warning for estrogen-only therapies includes this same language as well as the long-recognized advisory that estrogens increase the risk of endometrial cancer when used without a progestin.

The boxed warning also includes risk information that previously appeared in other sections of the labelling. Specifically, it states that because the Women's Health Initiative (WHI) study reported an increased risk of myocardial infarction, stroke, invasive breast cancer, and venous thromboembolism (VTE), estrogens and estrogens plus progestin therapies should be prescribed for the shortest duration consistent with treatment goals. The boxed warning also states that because other combinations of estrogens and progestins were not studied in the WHI, in the absence of comparable data, the risks identified in the study should be assumed to be similar for all postmenopausal hormone therapy (HT) products.

The FDA is contacting other manufacturers of HT products to urge them to implement similar revisions to the prescribing information for their products.

Conjugated estrogens/medroxyprogesterone acetate and conjugated estrogens are indicated for:

• Relief of moderate to severe vasomotor symptoms associated with menopause (the primary reason women seek treatment);

• Relief of moderate to severe symptoms of vulvovaginal atrophy associated with menopause;

• Prevention of postmenopausal osteoporosis inappropriately selected patients.

When used in women without menopausal symptoms for the prevention of postmenopausal osteoporosis, HT should be used only in women at significant risk for osteoporosis in whom non-estrogen therapies have been carefully considered.

Reference: Food and Drug Administration on http://www.fda.gov and http://www.premarin.com and http://www.prempro.com. 6 January 2003