Evista (raloxifene hydrochloride, 60 mg) has been approved for the prevention of osteoporosis in postmenopausal women. Evista, the first in a class of new drugs called selective estrogen receptor modulators (SERMs) to be approved by the FDA for marketing for the prevention of osteoporosis, is being studied for its selective ability to act like estrogen in some tissues but not in others.

The FDA reviewed data from 50 studies conducted in 28 countries to establish the safety and efficacy of Evista for the prevention of postmenopausal osteoporosis. More than 12,000 women have participated in the clinical program to date.

A total of 1,764 postmenopausal women participated in pivotal phase III osteoporosis prevention studies. In two studies, women were randomly assigned to take Evista or placebo. In the third study, women took Evista, placebo, or estrogen replacement therapy. All the women took calcium supplements. In each study, Evista was superior when compared with placebo in preventing bone loss in the lumbar spine and hip. These pivotal clinical trials also showed that Evista builds bone, although to a lesser extent than estrogen.

As with most drugs, Evista was associated with some side effects, the majority of which were reported as mild. A rare but serious side effect associated with Evista was an increase in venous thromboembolic events. The most-commonly observed side effect was hot flashes. Women taking Evista also reported a higher rate of leg cramps than women taking placebo. The leg cramps, generally reported as mild, did not cause women to discontinue Evista therapy.