Effect of monthly intravenous ibandronate injections on vertebral or non-vertebral fracture risk in Japanese patients with high-risk osteoporosis in the MOVER study

We examined the efficacy of intravenous (IV) ibandronate 1 mg/month in patient subgroups in the phase III MOVER study. Here we present results of analyses on the incidence of fractures in patients with prevalent vertebral fractures (1 or ≥2, and ≥3) at screening and femoral neck (FN) bone mineral density (BMD) T scores ≥−2.5 or <−2.5, and <−3.0 at baseline. The per-protocol set comprised 1134 patients (ibandronate 0.5 mg/month n = 376; ibandronate 1 mg/month n = 382; risedronate oral 2.5 mg/day n = 376). The incidence of vertebral fractures in patients with 1 or ≥2 prevalent vertebral fractures was 11.2 and 20.4 %, respectively, with ibandronate 1 mg/month, and 12.6 and 22.1 %, respectively, with risedronate. In patients with FN BMD T scores ≥−2.5 or <−2.5, the vertebral fracture incidence was 13.7 and 16.4 %, respectively, with ibandronate 1 mg/month, and 17.3 and 19.1 %, respectively, with risedronate. The incidence of non-vertebral fractures in patients with ≥2 prevalent vertebral fractures or FN BMD T score <−2.5 was 7.6 and 7.6 %, respectively, with ibandronate 1 mg/month, and 9.5 and 9.4 %, respectively, with risedronate. Fracture incidence was consistently lower, but not significant, with ibandronate 1 mg/month than with risedronate in patients with ≥2 prevalent vertebral fractures and FN BMD T score <−2.5. The efficacy of the fracture reduction of monthly IV ibandronate appears consistent and seemingly independent of the number of prevalent vertebral fractures or baseline BMD values.