Consistency of Fracture Risk Reduction in Japanese and Caucasian Osteoporosis Patients Treated with Teriparatide: a Meta-analysis

In the global Fracture Prevention Trial, teriparatide reduced the risk of vertebral and non-vertebral fractures and significantly increased BMD. Recently, a 12-month, phase 3, randomized, multicenter, double-blind, placebo-controlled trial with BMD as a primary endpoint was conducted to assess the effects of teriparatide in Japanese subjects at high risk of fracture. Although BMD was significantly increased in the Japanese study, the study was not statistically powered to assess the anti-fracture efficacy with teriparatide treatment. A meta-analysis was carried out testing whether teriparatide had consistent anti-fracture efficacy in Japanese patients compared to that observed in the global fracture trial. Three studies in which fracture data were available from prospectively scheduled spinal radiographs were included in the analysis. A systematic review of the literature (Medline, Embase) confirmed that no studies with teriparatide had been excluded from this analysis. There was no significant heterogeneity for vertebral and non-vertebral fractures among the studies included in the meta-analysis. Odds ratio estimates (95% CI) were 0.29 (0.20, 0.43) for vertebral fracture and 0.53 (0.32, 0.86) for non-vertebral fracture. There was also a consistent effect of teriparatide to increase BMD across all studies. Furthermore, our analysis demonstrated that teriparatide-mediated increases in spine BMD accounted for 25-32% of the reduction in vertebral fracture risk in the combined population including Caucasian and Japanese patients, which was similar to that derived from Caucasian patients. These results provide evidence for the consistency of anti-fracture efficacy with teriparatide treatment in Japanese patients compared to those observed in Caucasian patients.