Silverman SL et al. (2008) Efficacy of bazedoxifene in reducing new vertebral fracture risk in postmenopausal women with osteoporosis: results from a 3-year, randomized, placebo- and active-controlled clinical trial. J Bone Miner Res [doi: 10.1359/jbmr.080710]

Pharmacologic agents for postmenopausal osteoporosis aim to prevent the incidence of fractures by maintaining or increasing bone mineral density (BMD) and decreasing the rate of bone turnover. The novel selective estrogen receptor modulator bazedoxifene has been shown to achieve these goals in clinical studies of healthy postmenopausal women with normal or low BMD; Silverman and colleagues have now reported that bazedoxifene is safe and effective in postmenopausal women with osteoporosis.

The study enrolled women aged 55–85 years with osteoporosis who were randomly allocated to receive bazedoxifene 20 mg (n = 1,886), bazedoxifene 40 mg (n = 1,872), raloxifene 60 mg (n = 1,849) or placebo (n = 1,885) once daily. After 36 months, the incidence of new vertebral fracture was lower in all treatment groups compared with placebo (P <0.05). No significant differences in the incidence of new vertebral fractures or nonvertebral osteoporosis-related fractures were observed among the treatment groups. Compared with placebo, both dosages of bazedoxifene resulted in significant increases in BMD of the hip and spine (P <0.001) and reduced serum levels of the bone turnover markers osteocalcin and type-1 collagen C-telopeptide (P <0.001). These effects were similar to those seen with raloxifene treatment; however, in a subgroup of patients at higher risk of fracture, bazedoxifene 20 mg reduced the risk of nonvertebral fracture by 50% and 44% relative to placebo (P = 0.02) and raloxifene (P = 0.05), respectively.

Overall, bazedoxifene was well tolerated over the study period, and could represent a promising therapeutic option in women with postmenopausal osteoporosis.