Efficacy, safety, and compliance of ibandronate treatment for 3 years in postmenopausal Japanese women with primary osteoporosis

OBJECTIVES: The aim of this study was to examine the efficacy, safety, and adherence of ibandronate (IBN) treatment with or without vitamin D supplementation for 3 years in Japanese women with postmenopausal osteoporosis. METHODS: This prospective investigation included 27 patients treated with IBN alone (monotherapy group) and 29 patients receiving IBN and alfacalcidol (ALF) (combination group). Bone metabolism and bone mineral density (BMD) were measured before and at 18, 24, 30, and 36 months of therapy. Treatment discontinuation and fracture occurrence were assessed as well. RESULTS: Lumbar 1–4 BMD (L-BMD) was significantly increased in the monotherapy and combination groups by 3.9% and 7.2%, respectively, at 36 months, with significant gains in total hip BMD (H-BMD) of 3.7% and 4.9%, respectively. There were significant differences in L-BMD improvement between the groups at 18, 24, and 30 months (P < 0.05) and at 36 months (P < 0.01). Compared with pretreatment levels, the percentage changes of L-BMD and H-BMD were significant at all time points in the combination group and at all points apart from L-BMD at 36 months in the monotherapy group. In the monotherapy group, 14 patients dropped out during 3 years and 2 vertebral fractures occurred during the first year. In the combination group, 16 cases dropped out during 3 years and 1 nonvertebral fracture was noted during the first year. CONCLUSIONS: Our findings suggest that combination therapy of IBN and vitamin D is superior to monotherapy with regard to L-BMD improvements for 3 years, with both groups showing comparable safety and adherence to treatment.