Products
Radium-223 is commercially available as a solution for injection (Xofigo). It was approved in many countries in 2014 and in the United States and EU as early as 2013.
Structure and properties
Radium-223 is present in the drug as radium-223 dichloride (223RaCl2, Mr = 293.9 g/mol). It decays via a six-step process to lead-207 (Pb-207).
Effects
Radium-223 (ATC V10XX03) has antitumor and cytotoxic properties. The effects are due to the emission of alpha particles, causing breaks in the DNA double strands of tumor cells. The range of the particles is no more than 100 micrometers, which makes the drug effective only locally and results in fewer side effects. Radium-223 behaves like calcium in the body and is preferentially deposited in bone in the area of metastases. This imparts some selectivity for bone derivatives of the carcinoma. Radium-223 has a half-life of 11.4 days. In clinical trials, the drug has been shown to prolong median survival by more than three months compared with placebo.
Indications
For the treatment of patients with castration-resistant prostate cancer and symptomatic bone metastases without known visceral metastases.
Dosage
According to the SmPC. The drug is administered as a slow intravenous injection.
Contraindications
Radium-223 is contraindicated during pregnancy, in women who may be pregnant, and during lactation. For complete precautions, see the drug label.
Interactions
Combination in combination with chemotherapy has not been studied.
Adverse effects
The most common possible adverse effects include diarrhea, nausea, vomiting, and thrombocytopenia.
