Long-term administration of quarterly IV ibandronate is effective and well tolerated in postmenopausal osteoporosis: 5-year data from the DIVA study long-term extension.

UNLABELLED: Long-term bone mineral density (BMD) gains, bone marker levels, and safety of 3 mg quarterly intravenous (IV) ibandronate were studied in this 3-year extension to the Dosing IntraVenous Administration (DIVA) trial. Quarterly IV ibandronate consistently increased lumbar spine bone mineral density measured with dual-energy X-ray absorptiometry (DXA-BMD) over 5 years (8.1%) and was well tolerated in women with postmenopausal osteoporosis.

INTRODUCTION: Treatment with IV ibandronate regimens, 2 mg bimonthly and 3 mg quarterly, has been studied for up to 5 years in a long-term extension (LTE) to the 2-year DIVA trial.

METHODS: DIVA LTE is an open-label extension to a 2-year randomized, double-blind, double-dummy, noninferiority, phase III study (DIVA core). DIVA LTE involved postmenopausal women who had completed 2 years of DIVA core, comparing daily oral and IV ibandronate (≥75% adherence with IV ibandronate in year 2 of DIVA). Patients previously treated with 2 mg bimonthly or 3 mg quarterly IV ibandronate continued on the same regimen; patients who had received 2.5 mg daily oral ibandronate and placebo IV in DIVA core were switched to IV ibandronate.

RESULTS: Pooled analysis of 497 intent-to-treat (ITT) patients receiving IV ibandronate from DIVA core baseline showed consistent increases over 5 years in lumbar spine DXA-BMD (8.4% [95% confidence interval (CI) = 7.5, 9.3] with 2 mg bimonthly and 8.1% [95% CI = 7.2, 8.9] with 3 mg quarterly). Three-year data relative to DIVA LTE baseline in the full ITT population (756 patients randomized or reallocated from DIVA, including those previously on daily treatment) showed maintenance of DXA-BMD gains from DIVA core with further gains in lumbar spine DXA-BMD. These benefits are supported by sustained reductions in markers of bone metabolism. No tolerability concerns or new safety signals were observed.

CONCLUSIONS: Treatment with IV ibandronate 2 mg bimonthly or 3 mg quarterly is effective and well tolerated for up to 5 years in women with postmenopausal osteoporosis.