Efficacy of strontium ranelate on bone mineral density in men with osteoporosis

In an open-label, prospective, controlled, 12-month study the effects of strontium ranelate (SR, CAS 135459-87-9) or alendronate (CAS 129318-43-0) on bone mineral density (BMD) were compared in 152 men with primary osteoporosis. Patients were randomized to SR 2 g/day (n = 76) or alendronate 70 mg/week (n = 76) supplemented daily with 1200 mg calcium and 800 IU vitamin D. The main outcome measure was percent change in lumbar spine and total hip BMD from baseline. Mean BMD (+/- SD) increased by 5.8 +/- 3.7% at the lumbar spine and 3.5 +/- 2.8% at the total hip with SR compared to increases of 4.5 +/- 3.4% and 2.7 +/- 3.2%, respectively, with alendronate. Increases in BMD in the SR group are consistent with 1-year results from two pivotal fracture studies in postmenopausal women with osteoporosis. SR was associated with a 22% greater increase in BMD at the lumbar spine (p = 0.033) and 23% greater increase at the total hip (p = 0.002) than alendronate. New fractures were observed in 7 SR and 10 alendronate patients. Height loss (-0.1 +/- 0.7 cm) was less with SR compared with alendronate (-0.5 +/- 0.8 cm) (p = 0.026). SR was also associated with significantly greater reductions in back pain and analgesic use scores. Adverse events were experienced by 28 (37%) patients in the SR group and 38 (50%) patients in the alendronate group, none of which were serious. In men with osteoporosis, SR produced significantly greater mean increases in BMD over 12 months compared with alendronate, an agent already approved for male osteoporosis. Mean increases in BMD with SR in men were similar to those previously documented for this agent in postmenopausal women, suggesting that similar benefits on anti-fracture efficacy may be expected.