Romosozumab: A Review in Postmenopausal Osteoporosis

Romosozumab (Evenity^®), a humanized monoclonal antibody, promotes bone formation and inhibits bone resorption by inhibiting sclerostin, a protein involved in the regulation of bone formation. Subcutaneous romosozumab is approved in several countries, including those of the EU for treating severe osteoporosis as well as in the USA for osteoporosis in postmenopausal women at high risk of fracture. In pivotal phase III trials (FRAME and ARCH), 12 months' once-monthly romosozumab 210 mg significantly reduced vertebral and clinical fracture risk versus placebo and oral alendronate in postmenopausal women with osteoporosis. After patients transitioned from romosozumab to 12-24 months of subcutaneous denosumab or oral alendronate, fracture risks were significantly improved versus placebo-to-denosumab and alendronate-only treatment. In these trials and a phase IIIb trial, romosozumab significantly increased bone mineral density (BMD) relative to placebo, alendronate and subcutaneous teriparatide at 12 months, with these benefits maintained 12-24 months after patients transitioned from romosozumab to alendronate or denosumab in pivotal trials. Romosozumab had a generally manageable tolerability profile. While further clinical experience is needed to more definitively establish its efficacy and safety, including its CV safety, romosozumab extends the treatment options in postmenopausal women with osteoporosis who have a high risk of fracture and in those who have failed or are intolerant to other available osteoporosis therapy.