Objective: Phase 3 studies of postmenopausal women with or at risk for osteoporosis reported that, compared with placebo, bazedoxifene increased the incidence of hot flushes. The current study evaluated the vasomotor effects of bazedoxifene in healthy nonflushing postmenopausal women.
Methods: In this phase 2 study, nonflushing postmenopausal women (n = 494) were randomized to daily treatment with bazedoxifene 5, 10, or 20 mg; raloxifene 60 mg; or placebo for 12 weeks. The primary endpoint was the percentage of women reporting hot flushes at any time during the study; secondary endpoints included the mean number and severity of hot flushes and the mean number of days with hot flushes. Effects on bone turnover markers and lipid parameters were also evaluated.
Results: Over the 12-week study, 25.5% of placebo-treated women reported hot flushes. The incidence of hot flushes with bazedoxifene 5, 10, and 20 mg and raloxifene 60 mg was 26.0%, 33.7%, 27.6%, and 21.4%, respectively, with no significant differences from that with placebo. The active treatment groups showed no significant differences from placebo in the mean number or severity of hot flushes during week 12 or any 4-week period. Bazedoxifene and raloxifene showed beneficial effects on lipid parameters and markers of bone turnover. All doses of bazedoxifene were generally well tolerated and did not increase endometrial thickness, vaginal bleeding, or breast pain compared with placebo over 12 weeks of therapy.
Conclusions: Data from this phase 2 clinical trial suggest that bazedoxifene does not increase the incidence of hot flushes relative to placebo in nonflushing postmenopausal women.