SERMs are a class of drugs with mixed
estrogen agonist/antagonist effects that have great potential at targeting changes seen in the postmenopausal period.
Raloxifene is effective in preventing bone loss and may prevent fractures in
postmenopausal osteoporosis. It induces changes in
lipoprotein concentrations that should be cardioprotective. It has no stimulatory effect on the uterus and is well tolerated.
Raloxifene is an attractive alternative to HRT in preventing
postmenopausal bone loss, especially for women that are more concerned about the risk of
breast cancer or
vaginal bleeding. Unanswered questions include
raloxifene's effect on fracture incidence,
cardiac events, and
dementia; long-term safety data are also needed. Its potential role in the primary prevention of
breast cancer also needs large, long-term studies.
Tamoxifen has been used traditionally as adjuvant
therapy for
breast cancer, but new data indicate that it is effective in the primary prevention of
breast cancer in women at increased risk. Its effects on bone and
lipoproteins are attractive complementary effects when used in the subset of women at increased risk for
breast cancer. New generations of
SERMs are being developed that may have more potent
estrogen agonist effects on bone and
cardiovascular disease, or more potent
antiestrogen effects, especially at the breast. There will likely be a selection of
SERMs available, and the choice of
SERM for a woman will be tailored to her specific issues and risk profile.