The FDA has just approved a new drug for osteoporosis that works differently than existing medications. Romosozumab will be sold under the brand name Evenity. This injectable monoclonal antibody actually builds bone unlike many prior medications that work primarily by slowing bone breakdown. The FDA has only approved Evenity for postmenopausal women who are at very high risk of bone fracture because of osteoporosis. There are some potentially serious side effects.
The Pros and Cons of Bisphosphonates:
To date there have been no perfect osteoporosis drugs. Although osteoporosis is common, we do not have a magic wand to prevent fractures in older people. When someone breaks a hip it can lead to disability or death. That’s why building strong bones is important for healthy aging. You may find our radio show/podcast on this topic of interest:
For years, doctors relied upon a class of drugs called bisphosphonates. They work by slowing bone breakdown (aka resorption). These are drugs such as:
Zoledronic acid (Reclast)
Some experts describe bisphosphonates as brakes on the bone remodeling system. That is not a bad way to think of these drugs. It is not very physiological, though. Bone is constantly being broken down and rebuilt. Bisphosphonates throw a monkey wrench into the breakdown system.
Side effects of bisphosphonates include heartburn, abdominal pain and/or severe digestive tract upset. Fatigue is another possible complication. Less well recognized are symptoms of joint pain. You can read about this and other serious side effects at this link:
Other osteoporosis drugs include raloxifene (Evista), denosumnab (Prolia), teriparatide (Forteo) and abaloparatide (Tymlos). We will be expanding our Guide to Osteoporosis over the next few months and provide additional information on these and nondrug options to building bones.
The Pros and Cons of Evenity:
Some of the drug commentators have called Evenity a breakthrough. Others describe it as “an extraordinarily important drug” (New York Times, April 9, 2019). That’s because Evenity actually builds bone. According to Gina Kolata:
“In one study, spinal fractures occurred in 127 of 2,046 patients taking the new drug, compared with 243 of 2,047 taking aldendronate, an older drug.”
Here at The People’s Pharmacy we like to give you absolute numbers so you can see the research up close and personal. A study published in the New England Journal of Medicine (Oct. 20, 2016) reports that after one year of Evenity injections, 16 people out of 3,321 (0.5%) experienced a back fracture (vertebral fracture). In the placebo group, 59 out of 3,322 (1.8%) had a vertebral fracture.
Nonvertebral fractures (such as a hip fracture) occurred in “56 of 3,589 patients (1.6%) in the romosozumab group.” In the placebo group, 75 out of 3,591 people had a nonvertebral fracture (2.1%). That is an absolute risk reduction of 0.5%.
That’s the good news. The bad news is that Evenity almost did not get approved by the FDA. During its first review at the agency in 2017 the drug was rejected. That’s because it did not protect against non-vertebral fractures. We interpret that to mean that Evenity did not reduce the likelihood of hip fractures. The drug also appeared to have some disturbing cardiovascular complications.
Approval by the FDA now comes with some distinct cautions. It will only be appropriate for women who have experienced fractures because of osteoporosis. If a woman has several risk factors for developing a fracture, the drug would also be appropriate. And people who cannot tolerate older osteoporosis drugs or have not benefited from such drugs could also be prescribed Evenity.
Beware the Black Box Warning:
There will be a black box warning that the drug can increase the risk for cardiovascular events such as heart attacks and strokes. Anyone who has had a heart attack or a stroke or is at especially high risk for such events should probably be considered a poor candidate for Evenity.
Less worrisome side effects include injection site reactions, joint pain and headaches. Evenity is injected once a month for 12 months. After that, patients will likely need to switch to a different osteoporosis drug to maintain bone density. One analyst predicts the cost will be approximately $600 a month.