Evenity is a prescription injection used to treat osteoporosis in postmenopausal women at high risk for bone fractures. Its generic name is romosozumab, and it works differently from most osteoporosis drugs by actively building new bone rather than simply slowing bone loss. The treatment is given as two shots once a month for 12 months, after which patients typically switch to a different type of osteoporosis medication to maintain the gains.
How Evenity Works
Most osteoporosis treatments focus on slowing the breakdown of existing bone. Evenity takes a different approach. It targets a protein called sclerostin, which your bone cells naturally produce. Sclerostin acts like a brake on bone building: it blocks the signaling pathway that tells your body to form new bone, and it also accelerates bone breakdown. Evenity blocks sclerostin, effectively releasing that brake.
The result is a dual effect. Your body ramps up the creation of new bone tissue while simultaneously slowing the rate at which old bone is broken down. This combination leads to meaningful increases in bone density over a relatively short period. The bone-building effect is strongest in the first few months of treatment and gradually tapers by the end of the 12-month course, which is why treatment is capped at one year.
Who Is It For
The FDA approved Evenity specifically for postmenopausal women at high risk for fracture. “High risk” means one of three things: you’ve already had an osteoporotic fracture, you have multiple risk factors for fracture, or you’ve tried other osteoporosis treatments that either didn’t work or caused side effects you couldn’t tolerate. It is not a first-line treatment for mild bone loss. It’s reserved for situations where the fracture risk is serious enough to justify its cost, monitoring requirements, and cardiovascular considerations.
Dosing and What to Expect
Each monthly dose is 210 mg, split into two separate 105 mg subcutaneous injections given at the same appointment. A healthcare provider administers both shots, typically in the abdomen, thigh, or upper arm, rotating the injection site each visit. You cannot give yourself Evenity at home.
The full course is 12 monthly doses. Appointments are quick since the injections themselves take only a few minutes, but you’ll need to commit to showing up every month for a full year. Some soreness at the injection site is common. Other frequently reported side effects include joint pain and headache.
The Cardiovascular Warning
Evenity carries a boxed warning, the most serious type of safety alert the FDA issues, related to cardiovascular risk. The concern centers on heart attack and stroke. Patients who have had a heart attack or stroke within the past year should not take Evenity. For patients with other cardiovascular risk factors, the decision involves weighing the bone-building benefits against the potential heart-related risks.
This warning emerged from clinical trial data comparing Evenity to another osteoporosis drug, where a small but notable difference in cardiovascular events was observed. It doesn’t mean everyone on Evenity faces heart problems, but it does mean your doctor will evaluate your cardiovascular health before prescribing it.
Other Safety Considerations
Your blood calcium levels need to be normal before starting treatment. Low calcium (hypocalcemia) is a contraindication, meaning Evenity should not be used until calcium levels are corrected. You’ll also need adequate calcium and vitamin D intake throughout the treatment course.
Evenity should not be used at the same time as bisphosphonates, denosumab, or parathyroid hormone-based osteoporosis drugs. It’s designed as a standalone bone-building phase, not a combination therapy.
What Happens After 12 Months
This is one of the most important things to understand about Evenity: the bone density gains don’t last on their own. Once you stop the injections, the bone-building stimulus disappears and bone resorption can rebound, sometimes rising above the rate you started with. Without follow-up treatment, the density you gained can be lost relatively quickly.
That’s why the standard approach is to transition to an anti-resorptive medication after completing the 12-month Evenity course. Anti-resorptive drugs slow bone breakdown and help lock in the new bone that Evenity built. Think of it as a two-phase strategy: Evenity builds the bone, and the follow-up drug protects it. Skipping the second phase largely defeats the purpose of the first.
How Effective Is It
Evenity produces some of the largest bone density increases seen with any osteoporosis treatment. In clinical trials, patients gained significant bone mineral density at the spine and hip over the 12-month treatment period. These gains translated into meaningful reductions in fracture risk, particularly for vertebral (spinal) fractures, which are the most common type of osteoporotic fracture.
The strongest effects are seen at the lumbar spine, where Evenity improves both bone mass and bone strength. The hip also benefits, though the gains there tend to be somewhat smaller. When followed by an anti-resorptive drug, the fracture protection continues well beyond the initial 12 months.
Cost and Access
Evenity is expensive. Without insurance, the list price runs into thousands of dollars per month. Many insurance plans and Medicare Part B do cover it, but often with prior authorization requirements. Your provider will typically need to document that you meet the high-risk criteria and, in some cases, that you’ve tried other treatments first. The manufacturer offers a patient assistance program for those who qualify financially.
Because it requires monthly in-office injections, you’ll also need to factor in the time and logistics of regular healthcare visits for a full year. For patients who live far from their provider or have mobility challenges, this can be a practical consideration worth discussing upfront.