Abstract
Objective: Oral ibandronate 150 mg is the first bisphosphonate approved for once-monthly treatment of postmenopausal osteoporosis. To investigate whether once-monthly ibandronate 150 mg increases lumbar spine and total hip bone mineral density (BMD) to the same degree as weekly alendronate 70 mg.
Research design and methods: This was a 12-month, randomised, multinational, multicentre, double-blind, double-dummy, parallel-group, non-inferiority trial, conducted in 65 centres in North America, Latin America, Europe and South Africa. The study included postmenopausal women, mean lumbar spine (L2-L4) BMD T-score <-2.5 and >= -5.0. Patients received either ibandronate 150 mg once monthly or alendronate 70 mg once weekly.
Main outcome measures: Co-primary efficacy endpoints were 12-month change (%) from baseline in mean lumbar spine and total hip BMD. Changes (%) from baseline in trochanter and femoral neck BMD were also evaluated. Adverse events were monitored throughout. Once-monthly ibandronate was considered non-inferior to weekly alendronate if the lower boundary of the one-sided 97.5% confidence interval (CI) (or two-sided 95% C11) was >= -1.41 % for lumbar spine and >= -0.87% for total hip.
Results: Mean relative 12-month changes were 5.1% and 5.8% (95% CI for difference, -1.13, -0.23) in lumbar spine and 2.9% and 3.0% (95% CI for difference, -0.38, 0.18) in total hip BMD with once-monthly ibandronate and weekly alendronate, respectively; meeting the non-inferiority criteria at both sites. Gains in trochanter and femoral neck BMD were similar with both treatments. Both regimens were well tolerated. Trial registration: The MOTION study is registered with the International Federation of Pharmaceutical Manufacturers and Associations trial portal, under the ID number MM17385.
Conclusions: Once-monthly ibandronate was shown to be clinically comparable to weekly alendronate at increasing BMD after 12 months in both the lumbar spine and total hip.