Bazedoxifene acetate (WAY-140424; TSE-424) is an oral, nonsteroidal, indole-based selective estrogen-receptor modulator developed by Ligand Pharmaceuticals in collaboration with Wyeth Pharmaceuticals (NJ, USA) (now Pfizer) . It was developed using raloxifene as a template with the benzothiophene core substituted by an indole ring in order to obtain favorable effects on the skeleton and lipid metabolism with the additional improvement of a neutral effect on hot flushes and without stimulating the uterus or the breast. The drug is approved as a monotherapy for the prevention and treatment of osteoporosis and in combination with conjugated estrogens for the treatment of menopausal symptoms and prevention of osteoporosis. Bazedoxifene binds to both ERalpha and ERbeta with high affinity. Bazedoxifene acts as both a receptor agonist and/or antagonist, depending upon the cell and tissue type and target genes. Bazedoxifene decreases bone resorption and reduces biochemical markers of bone turnover to the premenopausal range. These effects on bone remodeling lead to an increase in bone mineral density (BMD), which in turn contributes to a reduction in the risk of fractures. Bazedoxifene functions primarily as an estrogen-receptor antagonist in uterine and breast tissues.