Effects of Bazedoxifene/Vitamin D Combination Therapy on Serum Vitamin D Levels and Bone Turnover Markers in Postmenopausal Women with Osteopenia: A Randomized Controlled Trial

Abstract

Background: This study aimed to evaluate the effectiveness of bazedoxifene/vitamin D combination therapy in preventing osteoporosis in postmenopausal women with osteopenia.Methods: This was an open-label, multicenter randomized-controlled, phase 4 clinical trial. Women between ages of 55 and 70 years in 9 medical tertiary centers in Korea were enrolled and assigned into 2 groups: an experiment group and a control group. The experimental group received bazedoxifene 20 mg/vitamin D 800 IU tablets for 6 months, and the control group received calcium 100 mg/vitamin D 1,000 IU tablets for 6 months.Results: A total of 142 patients (70 in the experimental group and 72 in the control group) were included. The least-square mean±standard error of change in propeptide of type I collagen after 3 months was -6.87±2.56% in the experimental group and 1.22±2.54% in the control group. After 6 months, it was -21.07±2.75% in the experimental group and 1.26±2.71% in the control group. The difference between the 2 groups was -22.33% (<i>p</i><0.01). The change of C-terminal telopeptide was -12.55±4.05% in the experimental group and 11.02±4.03% in the control group after 3 months. It was -22.0±3.95% and 10.20±3.89, respectively, after 6 months. The difference between the 2 groups was -32.21% (<i>p</i><0.01) after 6 months. There was no significant difference in adverse events between the 2 groups.Conclusions: The osteoporosis preventive effect and safety of administering bazedoxifene/vitamin D combination pill were confirmed in postmenopausal women who needed osteoporosis prevention.

Molecular and Cellular Mechanisms of Osteoporosis

“…The most studied preparations of the group of selective estrogen receptor modulators (SERMs) are raloxifene and bazedoxifene. These preparations bind to estrogen receptors and act as receptor antagonists in the uterus and mammary gland, and at the same time as agonists, regulating bone and lipid metabolism [168]. The beneficial effects of raloxifene in osteoporosis treatment are an increase in bone mass and mineral density due to a decrease in bone resorption [143].…”