Safety and effectiveness of monthly intravenous ibandronate injections in a prospective, postmarketing, and observational study in Japanese patients with osteoporosis

OBJECTIVES: This postmarketing, observational study evaluated the safety and effectiveness of monthly intravenous (IV) ibandronate in Japanese patients with osteoporosis. METHODS: Eligible patients received monthly IV ibandronate 1 mg for 12 months. Adverse drug reactions (ADRs) were evaluated. Changes in bone mineral density (BMD) and bone turnover markers (BTMs) were assessed using matched t-test analysis. Cumulative fracture rates were analyzed by Kaplan-Meier methodology. RESULTS: In total, 1062 patients were enrolled, of whom 1025 (n = 887 women, n = 138 men) were treated. Mean patient age was 77 years. Seventy-five ADRs were reported in 54 patients (5.26%). Four patients (0.39%) experienced serious ADRs, including one case of osteonecrosis of the jaw. Acute-phase reactions occurred in 21 patients (2.04%), and half of them arose after the first ibandronate injection. No new safety concerns were identified. Significant increases in BMD at 12 months relative to baseline were observed at the lumbar spine (4.84%, n = 187; 95% confidence interval [CI], 3.47%–6.21%), femoral neck (2.73%, n = 166; 95% CI, 1.46%–4.01%), and total hip (1.93%, n = 133; 95% CI, 0.80%–3.07%). Significant reductions were observed in all BTMs at 12 months (n = 174 in tartrate-resistant acid phosphatase-5b, n = 101 in procollagen type 1 N-terminal propeptide at baseline). The cumulative incidence of nontraumatic, new vertebral and nonvertebral fractures was 3.16% (95% CI, 2.12%–4.70%). Analyses in women only showed similar results to the overall population. CONCLUSIONS: These findings confirm the favorable safety and consistent effectiveness of ibandronate, and indicate that monthly IV ibandronate would be beneficial in daily practice for the treatment of Japanese patients with osteoporosis.