Romosozumab

Romosozumab is a monoclonal antibody that increases bone formation and BMD by inhibiting sclerostin, a protein that reduces osteoblast function and bone formation. Romosozumab reduces the risk of fractures, particularly vertebral and hip fractures, in postmenopausal women. It increases spine and hip BMD in men with osteoporosis.

Romosozumab's use is limited by strict eligibility criteria for PBS subsidy—therapy must be started by a specialist, the patient must have a T-score of –3 or less and they must have experienced at least one symptomatic new fracture after at least 12 months of therapy with an antiresorptive drug. Patients previously treated with PBS-subsidised teriparatide are not eligible for PBS-subsidised romosozumab.

Romosozumab has been associated with serious cardiovascular adverse events and is therefore not recommended for use in patients that have had a myocardial infarction or stroke.

If romosozumab is indicated, the recommended regimen is:

At the time of writing, romosozumab is available on the PBS for a total lifetime duration of 12 months. Romosozumab treatment should be followed by antiresorptive therapy (ie a bisphosphonate or denosumab) to preserve bone mass. See the PBS website for current information.

Serious skeletal adverse effects such as osteonecrosis of the jaw and atypical fractures of the femur have been rarely reported with romosozumab.