Treatment of postmenopausal osteoporosis with delayed-release risedronate 35 mg weekly for 2 years

Summary: Bone mineral density response to once weekly delayed-release formulation of risedronate, given before or following breakfast, was non-inferior to that seen with traditional immediate-release risedronate given daily before breakfast. Delayed-release risedronate is a convenient dosing regimen for oral bisphosphonate therapy that might avoid poor compliance. Introduction: This 2-year, randomized, controlled, non-inferiority study assessed the efficacy and safety of a delayed-release (DR) 35-mg weekly oral formulation of risedronate that allows subjects to take their weekly risedronate dose before or immediately after breakfast. Results from the first year of the study were published previously (McClung et al. Osteoporos Int 23(1):267-276, 2012); we now report the final results after 2 years. Methods: Women with postmenopausal osteoporosis were randomly assigned to receive risedronate 5 mg immediate-release (IR) daily (n = 307) at least 30 min before breakfast, or risedronate 35 mg DR weekly, either immediately following breakfast (FB, n = 307) or at least 30 min before breakfast (BB, n = 308). Bone mineral density (BMD), bone turnover markers (BTMs), fractures, adverse events, and bone histomorphometry were evaluated. Results: A total of 248 subjects (80.8 %) in the IR daily group, 234 subjects (76.2 %) in the DR FB weekly group, and 240 subjects (77.9 %) in the DR BB weekly group completed the 2-year study. After 2 years of treatment, BMD increases at the lumbar spine and total hip with the weekly DR doses similar to or greater than that with the IR daily dose. Decreases in BTMs were similar or significantly lower in the DR groups. Bone histomorphometry results did not differ among the DR weekly and the IR daily formulations. The three regimens were similarly well tolerated. Conclusions: Risedronate 35 mg DR weekly is as effective and as well tolerated as risedronate 5 mg IR daily, and will allow subjects to take their weekly risedronate dose immediately after breakfast

A novel monthly dosing regimen of risedronate for the treatment of postmenopausal Osteoporosis: 2-year data

This 2-year trial evaluated the efficacy and tolerability of a monthly oral regimen of risedronate. Postmenopausal women with osteoporosis were randomly assigned to double-blind treatment with risedronate 75 mg on 2 consecutive days each month (2CDM) or 5 mg daily. The primary end point was the percentage change from baseline in lumbar spine bone mineral density (BMD) at 12 months. Secondary end points included the change in BMD of the lumbar spine and proximal femur and in bone turnover markers as well as the number of subjects with at least one new vertebral fracture over 24 months. Among 1,229 patients who were randomized and received at least one dose of risedronate, lumbar spine BMD was increased in both treatment groups: mean percentage change from baseline was 4.2 ± 0.19 and 4.3 ± 0.19 % in the 75 mg 2CDM and 5 mg daily groups, respectively, at month 24. The treatment difference was 0.17 (95 % confidence interval −0.35 to 0.68). There were no statistically significant differences between treatment groups on any secondary efficacy parameters. Both treatment regimens were well tolerated. Risedronate 75 mg 2CDM was noninferior in BMD efficacy and did not show a difference in tolerability compared to 5 mg daily after 24 months of treatment in women with postmenopausal osteoporosis. This monthly regimen may provide a more convenient dosing schedule to some patients with postmenopausal osteoporosis