“Treatment data show that only one in five women who have experienced an osteoporotic fracture are started on treatment for the disease1, despite the fact that patients who experience an osteoporotic fracture are twice as likely to suffer a future fracture2,” said study lead author Felicia Cosman, M.D., medical director of the Clinical Research Center at Helen Hayes Hospital and professor of medicine at Columbia University College of Physician and Surgeons in New York. “The FRAME results demonstrate that romosozumab, with its dual effect of increasing bone formation and decreasing bone resorption, has the potential to reduce the risk of new vertebral and clinical fractures within 12 months, in addition to showing improvements in bone mass, with sustained benefits upon transition to denosumab thereby addressing a critical treatment need for patients at increased risk of fracture.”
FRAME (FRActure study in postmenopausal woMen with ostEoporosis), which enrolled 7,180 women, showed that those randomly assigned to receive a monthly subcutaneous 210 mg dose of romosozumab experienced a statistically significant 73 percent reduction in the relative risk of a new vertebral (spine) fracture through 12 months, the first co-primary endpoint, compared to those receiving placebo (fracture incidence 0.5 percent vs. 1.8 percent, respectively [p<0.001]). Of interest, the data showed that by six months, new vertebral fractures occurred in 14 romosozumab and 26 placebo patients, and between six to 12 months, fractures occurred in two additional romosozumab vs. 33 additional placebo patients.
In those patients who received romosozumab in year one, fracture risk reduction persisted through month 24 after both groups transitioned to denosumab treatment in the second year of the study; there was a statistically significant 75 percent reduction in the risk of vertebral fracture at month 24 (the other co-primary endpoint) in patients who received romosozumab followed by denosumab vs. placebo followed by denosumab (fracture incidence 0.6 percent vs. 2.5 percent, respectively [p<0.001]). In the second year of the study, new vertebral fractures occurred in five patients who transitioned from romosozumab to denosumab and 25 patients who transitioned from placebo to denosumab.
When looking at clinical fractures, which encompass all symptomatic fractures (both non-vertebral and painful vertebral fractures), patients receiving romosozumab experienced a statistically significant 36 percent reduction in the relative risk of a clinical fracture, a secondary endpoint, through 12 months compared to those receiving placebo (fracture incidence 1.6 percent vs. 2.5 percent, respectively [p=0.008]). A 33 percent reduction in relative risk of clinical fracture was observed through 24 months after patients transitioned from romosozumab to denosumab compared to patients transitioning from placebo to denosumab (nominal p=0.002, adjusted p=0.096).
Romosozumab resulted in a 25 percent reduction compared to placebo in the relative risk of non-vertebral fractures through month 12, another secondary endpoint, but the reduced risk was not statistically significant (fracture incidence 1.6 percent vs. 2.1 percent, respectively, [p=0.096]). For the non-vertebral fracture endpoint, the overall fracture incidence in the study was lower than expected (2.1 percent in the placebo group in year one vs.an expected rate of 3.5 percent).
In a substudy of 126 subjects, romosozumab increased bone mineral density with gains of 9.7 percent and 4.7 percent from baseline by six months at the lumbar spine and total hip, respectively, and gains of 13.3 percent and 6.8 percent at 12 months (all comparisons vs.placebo [p<0.001]). Bone mineral density continued to increase in the romosozumab group after transitioning to denosumab, reaching a 17.6 percent and 8.8 percent increase from baseline at the lumbar spine and total hip, respectively, at 24 months ([p<0.001] compared to placebo-to-denosumab group for all comparisons).
“Osteoporotic fractures are common, resulting in far-reaching consequences for individuals and their families, as well as for society as a whole,” said Dr. Pascale Richetta, head of bone and executive vice president, UCB. “To reduce the growing global burden of this prevalent chronic disease more decisive steps need to be taken now for identifying, diagnosing and appropriately treating people with osteoporosis at an increased risk of fracture.”
“We are pleased to see nearly 15 years of sclerostin antibody research reinforced with these Phase 3 data. Romosozumab with its dual effect as a bone builder and anti-resorptive has the potential to play a distinct and important role in the treatment of women with postmenopausal osteoporosis at increased risk of fracture,” said Sean E. Harper, M.D., executive vice president of Research and Development at Amgen. “These positive FRAME study results are the basis of our Biologics Licensing Agreement that we submitted to the FDA in July, and we look forward to working with regulatory authorities to help make this potential treatment option available to patients.”
The percentage of patients with adverse events and serious adverse events in the 12-month double-blind period and 24-month study period were balanced overall between the treatment groups. Injection site reactions, mostly mild in severity, were reported in 5.2 percent of patients in the romosozumab treatment group and 2.9 percent in the placebo group during the 12-month period. There were two positively adjudicated events of osteonecrosis of the jaw in the romosozumab treatment group, one after completing romosozumab dosing and the other after completing romosozumab treatment and receiving the initial dose of denosumab. There was one positively adjudicated event of atypical femoral fracture after three months of romosozumab treatment. Adjudicated serious cardiovascular events and cardiovascular deaths were balanced between treatment groups.
- Wilk A et al. Post-fracture pharmacotherapy for women with osteoporotic fracture: analysis of a managed care population in the USA. Osteoporosis Int. 2014;25(12):2777-2786.
- International Osteoporosis Foundation. Stop at One. One Fracture Leads to Another. http://share.iofbonehealth.org/WOD/2012/patient_brochure/WOD12-patient_brochure.pdf. Accessed August 29, 2016.