RALOXIFENE

Raloxifene is a selective estrogen receptor modulator which mimics the effects of estrogens on bone and blood lipid levels without stimulato ry effects on the breast or uterus. Raloxifene inhibits estrogen-depen dent proliferation of human breast cancer cells in vitro and developme nt of induced mammary tumours in rats in vivo. Raloxifene inhibits bon e resorption induced by estrogen deficiency in murine and human studie s and lowers serum cholesterol levels. In clinical studies in postmeno pausal women, raloxifene 60 mg/day for 2 years significantly increased bone mineral density compared with placebo. In comparative clinical s tudies, raloxifene 60 mg/day had more modest effects than conjugated e strogens 0.625 mg/day on bone resorption and formation parameters and appeared to be less effective in increasing bone mineral density. In o lder postmenopausal women with existing bone fractures, raloxifene 60 or 120 mg/day for 1 year produced modest increases in bone mineral den sity. The most common treatment-related adverse events in raloxifene r ecipients were hot flushes and leg cramps. The risk of venous thromboe mbolic events is increased during raloxifene therapy. In contrast with conjugated estrogens 0.625 mg/day, raloxifene 200 or 600 mg/day for 8 weeks or 150 mg/day for 1 year did not produce endometrial proliferat ion.