Treatment with denosumab restored cortical bone loss at the radius, which was associated with decreased wrist fracture rates, in women with postmenopausal osteoporosis, according to an analysis of data from the FREEDOM and FREEDOM Extension trials.
These data were presented at the American Society for Bone and Mineral Research (ASBMR) 2014 Annual Meeting in Houston, Texas.
In this analysis, John P. Bilezikian, MD, of the Columbia University College of Physicians & Surgeons in New York, and colleagues evaluated the cross-over group of participants in the FREEDOM and FREEDOM Extension trials.
The 2,207 women included in this analysis received placebo for 3 years during FREEDOM and then switched to denosumab 60 mg every 6 months for 5 years of the Extension trial. Participants received daily calcium and vitamin D, according to the researchers.
Mean 1/3 radius T-score was –2.53 at FREEDOM baseline, the researchers reported, with bone mineral density (BMD) decreasing progressively and significantly (–1.2%) with the administration of daily calcium and vitamin D alone.
Conversely, bone loss stopped and was even reversed after denosumab treatment during the Extension trial. After 5 years of treatment, BMD had significantly increased (1.5%) vs. Extension baseline levels, according to the data.
Wrist fracture rate during the first 3 years of denosumab treatment (0.96 per 100 subject-years) was similar to what was observed during the FREEDOM placebo period (1.02 per 100 subject-years). The researchers noted BMD was returning to original baseline levels during this time.
Two more years of treatment with denosumab, however, yielded additional increases in BMD, which paralleled a decline in wrist fracture rate (0.58 per 100 subject-years) that was significantly lower than that observed during the FREEDOM placebo period (rate ratio=0.57; 95% CI, 0.34-0.95), according to the study results.
“These data provide evidence, for the first time, of the clinical importance of reversing cortical bone loss,” the researchers wrote in their abstract.
- Bilezikian JP et al. Abstract 1047. Presented at: American Society for Bone and Mineral Research 2014 Annual Meeting; Sept. 12-15, 2014; Houston, Texas.