Bisphosphonate therapy associated with fewer vertebral fractures in men

Two annual injections of zoledronic acid reduced risk of vertebral fracture among men with osteoporosis, according to a study supported by the drug's manufacturer.

Researchers conducted a multicenter, double-blind, placebo-controlled trial that randomly assigned nearly 1,200 men ages 50 to 85 with osteoporosis to receive an intravenous infusion of zoledronic acid (5 mg) or placebo at the initiation of the study and a repeat infusion at 12 months into the study.

Men were eligible to participate if they had a bone mineral density T score of –1.5 or less at the total hip or femoral neck and one to three prevalent vertebral fractures of mild or moderate grade. Men without fractures were eligible if they had a bone mineral density T score of –2.5 or less at the total hip, femoral neck or lumbar spine.

The study was designed and supported by Novartis. Results appeared online Nov. 1 at the New England Journal of Medicine.

New morphometric vertebral fractures occurred in 1.6% of the treatment group and 4.9% of the placebo group (relative risk, 0.33; 95% CI, 0.16 to 0.70; P=0.002). Men in the treatment group also had fewer moderate-to-severe vertebral fractures (P=0.03) and less height loss (P=0.002) compared to those on placebo. Men in the active treatment group also had higher bone mineral density and lower bone-turnover markers (P<0.05 for both comparisons).

The trial supports the idea that antiresorptive treatments are effective in both men and women, researchers wrote. “Despite the fact that current public health efforts to detect osteoporosis and prevent fractures in men are inadequate, the ability to establish detection and treatment recommendations has been limited because of the absence of unambiguous evidence of effective antifracture therapies in men,” researchers wrote. “Although our findings with zoledronic acid do not imply that all data on drugs for osteoporosis in women can be extrapolated to men, our study should provide the confidence to proceed.”