Effectiveness of Bazedoxifene for Prevention of Glucocorticoid-induced Bone Loss in RA Patients

* The purpose of this study is to study the effectiveness of bazedoxifene in preventing loss of bone mineral density (BMD) and trabecular bone score (TBS), and any fractures in postmenopausal rheumatoid arthritis (RA) patients receiving long-term GCs. * This is a randomized, controlled, open-label extension study for 48 or 56 weeks. At study entry, all patients will receive elemental calcium (1200 mg daily) and vitamin D (800 IU daily) and will be randomized by blocks of two to receive either bazedoxifene (20 mg/day) or none.