A head-to-head study comparing alendronate, a commonly prescribed osteoporosis medication, to a newer bone loss drug called romosozumab found that romosozumab better reduced fracture risk in postmenopausal women with osteoporosis.
The study was published in the New England Journal of Medicine in September 2017, and it shows promise for an innovative new medication to prevent potentially life-threatening fractures. However, the therapy is not yet approved by the U.S. Food and Drug Administration (FDA), as it bears concerning cardiovascular risk.
This study compared 2 bone loss drugs: The first is alendronate (common brand names include Fosamax, Binosto, and Fosamax Plus D), which is a typical first-line treatment for osteoporosis. This drug belongs to a large class of osteoporosis medications called bisphosphonates. Alendronate slows bone loss, thereby improving bone mineral density (BMD), and decreasing the risk of fractures in your spine, hip, and other bones.
The second drug studied is called romosozumab (brand name Evenity). This is a newer therapy than alendronate. Romosozumab promotes the formation of new bone by blocking a substance called sclerostin, which inhibits the growth of new bone.
The research team studied 4,093 women (an average age of 74 years) who had osteoporosis and a history of fracture. The women were split into 1 of 2 groups: Either they would have 12 months of alendronate therapy or 12 months of romosozumab therapy. After the first year of treatment, all the patients received alendronate for the next 12 months.
At the end of the 24-month study period, the researchers found that the women who took romosozumab had a 48% reduced risk of vertebral fracture (6.2% of the romosozumab group suffered a fracture, while 11.9% of the alendronate group reported a fracture).
The romosozumab group also fared better regarding clinical fracture risk (such as an arm or leg fracture)—9.7% in that group had a clinical fracture compared to 13.0% in the group that only took alendronate.
“In our trial, the effect of romosozumab on the risk of fracture was rapid: The risks of new vertebral fracture and clinical fracture were significantly lower with romosozumab than with alendronate at 12 months,” wrote the study authors.
Concerns About Heart Risk
While romosozumab performed better at reducing fractures, the authors noted that it was also associated with serious cardiovascular events, such as heart attack or stroke. Cardiovascular events occurred in 2.5% of the romosozumab group compared with 1.9% in the alendronate-only group. Outside of cardiovascular events, the authors found no difference in adverse events between the 2 groups.
In July 2017, the FDA rejected the approval of romosozumab because of its risk of serious adverse cardiovascular events compared alendronate based on a previous study.
What this Research Means for You
Osteoporosis increases your risk for fracture, and injuries impacting the bones of your spine and hip are particularly serious. Fortunately, drug therapies are advancing at a rapid rate—and many, including the 2 drugs noted in this study—are extremely effective at preventing fractures and promoting bone growth.
While the overall safety of romosozumab needs further study before the drug earns FDA approval, you may consider speaking to your doctor about whether any newly approved osteoporosis medications are worth exploring. You can also use the opportunity with your doctor to review your current medication regimen and discuss whether you should pursue other therapies (such as exercise) to strengthen your bone health.