Effectiveness of bazedoxifene in preventing glucocorticoid-induced bone loss in rheumatoid arthritis patients

OBJECTIVE: To evaluate the effectiveness of bazedoxifene in preventing bone loss in patients with rheumatoid arthritis (RA) receiving low-dose glucocorticoids (GCs). METHODS: In this randomized, controlled, open-label study, we assigned postmenopausal women with osteopenia who had been receiving low-dose GCs for RA to two groups: a group receiving bazedoxifene (20 mg/day) with elemental calcium 1200 mg and vitamin D 800 IU daily (bazedoxifene group) and a group receiving the same doses of calcium and vitamin D only (control group). As primary outcome, bone mineral density (BMD) change in the lumbar spine (L-spine) from baseline to 48 weeks was assessed. Changes in BMD in the femur, trabecular bone score, bone turnover markers, and development of fracture were assessed as secondary outcomes. For intention-to-treat analysis, 20 completed data sets were created by applying multiple imputations by chained equations. RESULTS: A total of 114 patients (57 patients in each group) were recruited. A significant increase in L-spine BMD (0.015 g/cm(2), P = 0.007) was observed in the bazedoxifene group, and the increase was significantly higher than in the control group (0.013, 95% CI 0.0003–0.026, P = 0.047). Reductions in bone turnover markers in the bazedoxifene group were significantly greater than in the control group. Only one fracture was observed in the bazedoxifene group, while four fractures developed in the control group. CONCLUSION: In postmenopausal patients with RA receiving low-dose GCs, bazedoxifene improved BMD and reduced bone turnover markers. However, the change in BMD did not exceed the least significant change. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02602704. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13075-021-02564-1.