Radium-223 (Xofigo)

General information

Class/mechanism: Radioactive pharmaceutical agent (radium-223) that mimics some biologic behaviors of calcium and is incorporated into areas with increased bone turnover, such as bone metastases, by forming complexes with hydroxyapatite. Radium-223 emits alpha radiation at the site of bone metastases, which causes double-strand DNA breaks in nearby cells. The limited penetration of alpha radiation (less than 100 micrometers/uM, less than 10 cell diameters) is believed to limit the risk of adverse side effects. Radium-223's half-life is 11.4 days. Its specific activity is 1.9 MBq (51.4 microcurie)/ng; molecular weight of ²²³RaCl₂: 293.9 g/mol.

Route: IV
Extravasation: no information

For conciseness and simplicity, HemOnc.org currently will focus on treatment regimens and not list information such as: renal/hepatic dose adjustments, metabolism (including CYP450), excretion, monitoring parameters (although this will be considered for checklists), or manufacturer. Instead, for the most current information, please refer to your preferred pharmacopeias such as Micromedex, Lexicomp, UpToDate (courtesy of Lexicomp), or the prescribing information.

Diseases for which it is used

• Prostate cancer

Patient drug information

• Radium-223 (Xofigo) patient drug information (Chemocare)
• Brief patient counseling information can be found in the Radium-223 (Xofigo) package insert

History of changes in FDA indication

• 2013-05-15: FDA approved for the treatment of patients with castration-resistant prostate cancer, symptomatic bone metastases and no known visceral metastatic disease. (Based on ALSYMPCA)

History of changes in EMA indication

• 2013-11-13: Initial marketing authorization as Xofigo. Xofigo is indicated for the treatment of adults with castration-resistant prostate cancer, symptomatic bone metastases and no known visceral metastases. (Based on ALSYMPCA)

History of changes in Health Canada indication

• 2013-12-12: Initial notice of compliance (details unavailable)

History of changes in PMDA indication

• 2016-03-28: Initial approval for the treatment of castration-resistant prostate cancer with bone metastases.

Also known as

• Generic names: Ra-223, Radium Ra 223 dichloride, Radium-223 chloride
• Brand names: Alpharadin, Xofigo