Denosumab

How it works

It binds and neutralises RANK ligand, preventing activation of RANK on osteoclasts, thereby inhibiting osteoclast formation and function and reducing bone resorption.

Prescribing in practice

• Correct hypocalcaemia before each dose and ensure adequate calcium and vitamin D, as denosumab can cause significant hypocalcaemia, particularly in renal impairment.
• Stopping denosumab causes a rapid rebound increase in bone turnover with risk of multiple vertebral fractures, so doses must be given on schedule and a plan for alternative antiresorptive cover is needed if it is discontinued.
• It is associated with osteonecrosis of the jaw and atypical femoral fractures — encourage dental health before and during treatment and review the SPC, noting the osteoporosis and oncology products differ in strength and frequency.

Monitoring

Check calcium (and renal function) before dosing and after starting, and remain alert for jaw symptoms and new thigh or groin pain during treatment.

Counselling the patient

• Take your calcium and vitamin D as advised and do not miss your scheduled injections.
• Tell your clinician before stopping treatment, as missing doses can lead to spinal fractures.
• Maintain good dental hygiene and report jaw pain or non-healing mouth sores, and any new thigh or groin pain.

Evidence & guidelines

NICE recommends denosumab as an option for osteoporosis in selected patients, and the MHRA has warned about rebound vertebral fractures after stopping and the risk of osteonecrosis of the jaw.