For women with osteoporosis, long-term treatment with denosumab is associated with further reductions in nonvertebral fracture rates, according to results published in The Journal of Clinical Endocrinology & Metabolism.
The study included women aged 60 to 90 years with a bone mineral density T-score lower than -2.5 but ≥-4.0 at the lumbar spine or total hip. Participants were randomly assigned 1:1 to either subcutaneous denosumab 60 mg every 6 months (long-term group) or placebo for 3 years (crossover group) as part of the FREEDOM trial (Clinicaltrials.gov identifier: NCT00089791).
Eligible participants could then enroll in the open-label Extension trial (Clinicaltrials.gov identifier: NCT00523341). These participants received subcutaneous denosumab 60 mg every 6 months for 7 years.
The main outcomes were exposure-adjusted subject incidence per 100 subject-years of nonvertebral fracture during denosumab treatment years 1 to 3 and 4 to 7 for all subjects and for years 4 to 10 for the long-term group only. The researchers also measured rate ratios for years 4 to 7 or 4 to 10 compared with 1 to 3.
Among 4074 participants in the Extension study, 2343 were long-term and 1731 were crossover.
For all participants, the rate of nonvertebral fracture was 2.15 (95% CI, 1.90-2.43) during years 1 to 3 compared with 1.53 (95% CI, 1.34-1.74) during years 4 to 7 of denosumab treatment (rate ratio, 0.72; 95% CI, 0.61-0.86; P <.001).
Among participants in the long-term group, the rate of nonvertebral fracture was 1.98 (95% CI, 1.67-2.34) during years 1 to 3 compared with 1.44 (95% CI, 1.24-1.66) during years 4 to 10 (rate ratio, 0.74; 95% CI, 0.60-0.93; P =.008).
“These data further support the long-term administration of denosumab, a potent antiresorptive therapy, in postmenopausal women with osteoporosis and a hip [bone mineral density] T-score ≤-1.5 to improve bone strength and minimize the risk of fragility fractures,” the researchers wrote.
Disclosure: This study was sponsored by Amgen Inc. Multiple authors disclosed affiliations with pharmaceutical companies. Please see the original reference for complete disclosure information.
Ferrari S, Butler PW, Kendler DL, et al. Further nonvertebral fracture reduction beyond 3 years for up to 10 years of denosumab treatment [published online May 24, 2019]. J Clin Endocrinol Metab. doi:10.1210/jc.2019-00271