Raloxifene: Conclusions

Conclusions
Among more recently developed options, certain SERMs may be unique in that they hold promise for protective effects in the skeleton and the cardiovascular system, while at the same time demonstrating antiproliferative actions in reproductive tissues.

Raloxifene, a new SERM, has undergone extensive clinical investigation. At present it is the only SERM approved for treating and preventing osteoporosis in postmenopausal women, as studies have found that it prevents bone resorption and maintains bone mass in women in early postmenopause, and reduces the risk for osteoporotic vertebral fractures by as much as 50% in women who already have osteoporosis.

At the same time, raloxifene has few side effects. Because of its estrogen antagonist action in the endometrium and breast, in clinical trials it produced no more vaginal bleeding or breast pain than did placebo.

Although raloxifene is currently indicated only for treating and preventing osteoporosis, it also shows some effects that may eventually make it useful in preventing cardiovascular disease and breast cancer. It changes lipid levels in directions that should reduce cardiovascular risk, and its effect on clinical cardiovascular outcomes is being evaluated. In a trial in osteoporotic, postmenopausal women, raloxifene reduced the incidence of new cases of breast cancer by approximately 75% after 3 years (60)

Further research is needed to clarify its role in the prevention of cardiovascular disease and breast cancer. These effects may eventually prove to be the desired combination for many postmenopausal women, which could then result in good long-term compliance with this regimen.

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Address: Angelo A. Licata, MD, PhD, Department of Endocrinology, A30, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, e-mail licataa@ccf.org.