radium-223 dichloride: clinical use

Prescribing considerations

• Confirm symptomatic osteoblastic bone metastases, absence of known visceral metastases and suitability under the licensed prior-treatment criteria.
• Benefit is unestablished for asymptomatic bone metastases and may be reduced with low osteoblastic disease burden.
• Complete clinically indicated management of imminent or established spinal-cord compression before starting or resuming treatment.
• Use caution with compromised marrow reserve, extensive bone infiltration or acute inflammatory bowel disease.
• Assess baseline fracture risk and consider appropriate bone-protective measures.
• Use only through authorised radiopharmaceutical services with radiation-protection procedures.

Contraindications and cautions

• Concomitant abiraterone acetate and prednisone or prednisolone.
• Not recommended with systemic anticancer therapy other than an LHRH analogue.
• Do not use in women who are or may be pregnant or breastfeeding.

Monitoring

• Full blood count at baseline and before every administration; apply the product-specific haematological criteria.
• Assess bone status and fracture risk before treatment, during treatment and for at least 24 months after discontinuation.
• Monitor hydration and investigate severe or persistent diarrhoea, nausea or vomiting.
• Monitor for fracture, infection, bleeding and jaw symptoms.

Clinical pharmacology

Radium-223 is a calcium mimetic that complexes with hydroxyapatite in areas of increased bone turnover. Its short-range, high-linear-energy-transfer alpha emissions produce double-strand DNA breaks. It is not metabolised; elimination is predominantly faecal, with minimal urinary excretion.

Formulation and product differences

• The selected product is a clear, colourless, isotonic, ready-to-use solution for intravenous injection in a single-use vial.
• It must not be diluted or mixed with other medicinal products.