30th ASBMR 2008
[M360] Continued Evidence for Safety and Efficacy of Risedronate in Men with Osteoporosis: Outcome of the 2-year Open-Label Extension Study of MASTER
S Boonen, ES Orwoll, D Wenderoth, KJ Stoner, R Eusebio, PD Delmas.. University Hospital, Leuven; Oregon Health Sciences University; P & G Pharmaceuticals; INSERM Research Unit 403.
The objective of this 2-year open-label extension to the 2-year, double-blind, placebo-controlled study (MASTER) was to continue to assess the safety of 35 mg once-a-week (OAW) risedronate in men with osteoporosis. 218 of the 284 men (67 of 93 placebo group [Pla/Ris]; 151 of 191 risedronate group [Ris/Ris]) from the initial blinded study were enrolled in this extension study. Safety variables included adverse events (AEs), laboratory data, vital signs, physical examinations, and changes in lumbar spine, total proximal femur, femoral neck, and femoral trochanter BMD and bone turnover markers (BTMs) including type I collagen C-telopeptide (CTX), type I collagen N-telopeptide/creatinine (NTX/Cr), and bone-specific alkaline phosphatase (BAP). BMD was measured at Months 36 and 48 of the 2-year extension; BTMs were measured at Months 27, 30, 36 and 48 of the 2-year extension.
The mean increase from baseline at Year 4 in lumbar spine BMD for patients receiving risedronate 35 mg OAW for all 4 years (Ris/Ris group) was 7.9% (6.6-9.1, 95% CI, n=128). These Ris/Ris patients also continued to show BMD response at other skeletal sites. The mean increase from baseline at Year 4 in lumbar spine BMD for the placebo patients that received risedronate 35 mg OAW for the 2 years of the open-label extension study (Pla/Ris group) was 6.2% (4.6-7.9, 95% CI, n=54), which is similar to the response observed in risedronate-treated patients during the initial 2-year, double-blind study period (5.98% [5.22-6.73, 95% CI], n=172). Similar patterns were observed in the Pla/Ris group at other skeletal sites.
Similar reductions in NTX/Cr, CTX, and BAP were found at Years 3 & 4 between the 2 groups. In general, greater decreases in BTMs were observed in the Pla/Ris group during the open-label extension study while taking risedronate 35 mg OAW than during the double-blind study while taking placebo.
The 2 groups were similar in overall percentages of patients with AEs (68.7% Pla/Ris, 66.9% Ris/Ris), serious AEs (11.9% Pla/Ris, 13.9% Ris/Ris), upper GI AEs (10.4% Pla/Ris, 8.6% Ris/Ris), and overall musculoskeletal AEs (11.9% Pla/Ris, 13.9% Ris/Ris).
In conclusion, the Pla/Ris group in the 2-year open-label extension study showed similar safety and efficacy results compared to the Ris/Ris group in the first 2 years of the study. Patients who received risedronate for 4 years in total showed similar safety and efficacy to that observed in women with postmenopausal osteoporosis treated with risedronate for 4 years.
S. Boonen, P&G 2.
The Alliance for Better Bone Health (Procter & Gamble Pharmaceuticals and sanofi-aventis)
Date: Monday, September 15, 2008
Session Info: Poster: Osteoporosis Treatment (Clinical): Bisphosphonates (11:30 AM-2:30 PM)
Presentation Time: 11:30 AM