Abstract
Oral daily ibandronate was investigated for the prevention of bone loss in postmenopausal women without osteoporosis (n = 653). BMD at the lumbar spine and hip were significantly increased (3.1% and 1.8%, respectively; p ≤ 0.0001 versus placebo) with 2.5 mg ibandronate after 24 months. Oral ibandronate is a promising option for the prevention of postmenopausal bone loss. Introduction: Further strategies to manage patients most at risk from developing postmenopausal osteoporosis are required. The objectives of this multicenter, double-blind, randomized, placebo-controlled study were to examine the efficacy, tolerability, and optimal dose of oral daily ibandronate in the prevention of bone loss in postmenopausal women. Materials and Methods: In total, 653 women (mean bone mineral density [BMD] T-score > -2.5 at the lumbar spine), who had been postmenopausal for at least 1 year, were allocated to one of four strata based on time since menopause and baseline lumbar spine BMD. Women were randomized to receive calcium (500 mg daily) plus either placebo (n = 162) or ibandronate 0.5 mg (n = 162), 1 mg (n = 166), or 2.5 mg (n = 163) as once-daily oral treatment for 2 years. The primary endpoint was the mean percent change in lumbar spine BMD with ibandronate versus placebo. Results and Conclusions: After 2 years, oral daily ibandronate produced a dose-related and sustained maintenance or increase in BMD at the lumbar spine and hip (total hip, femoral neck, trochanter), together with a dose-related reduction in the rate of bone turnover. The greatest nominal increases in spinal and hip BMD were observed with the 2.5-mg dose, which produced statistically significant BMD gains compared with placebo at 6 months and all subsequent time-points at the spine and hip (3.1% and 1.8% increase in lumbar spine and total hip BMD, respectively, versus placebo; p ≤ 0.0001 after 24 months). Oral daily ibandronate was well tolerated with an incidence of upper gastrointestinal adverse events similar to placebo. No safety concerns were identified. In summary, oral daily ibandronate 2.5 mg decreases bone turnover, preserves or increases BMD in the spine and proximal femur, and is well tolerated. Oral ibandronate provides a promising option for the prevention of bone loss in postmenopausal women.