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 (<100 micrometers/uM, <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

Clinical trials

• Nilsson S, Strang P, Aksnes AK, Franzèn L, Olivier P, Pecking A, Staffurth J, Vasanthan S, Andersson C, Bruland OS. A randomized, dose-response, multicenter phase II study of radium-223 chloride for the palliation of painful bone metastases in patients with castration-resistant prostate cancer. Eur J Cancer. 2012 Mar;48(5):678-86. Epub 2012 Feb 15. PubMed
• Overall Survival Benefit of Radium-223 Chloride (Alpharadin) in the Treatment of Patients With Symptomatic Bone Metastases in Castration-Resistant Prostate Cancer (CRPC): A Phase III Randomised Trial (ALSYMPCA)
  • A Phase III Study of Alpharadin (Radium-223)in Patients With Symptomatic Hormone Refractory Prostate Cancer With Skeletal Metastases (ALSYMPCA)
• Study of Radium-223 for the Palliation of Painful Bone Metastases in Hormone Refractory Prostate Cancer (HRPC) Patients
• A Study of Alpharadin® With Docetaxel in Patients With Bone Metastasis From Castration-Resistant Prostate Cancer (CRPC)
• Radium-223 Chloride (Alpharadin) in Castration-Resistant (Hormone-Refractory) Prostate Cancer Patients With Bone Metastases
• A Study of Alpharadin® in Breast Cancer Patients With Bone Dominant Disease no Longer Considered Suitable for Hormone Therapy

Patient drug information

• Brief patient counseling information can be found on page 14 of the package insert

History of changes in FDA indication

• 5/15/2013: FDA approved "for the treatment of patients with castration-resistant prostate cancer, symptomatic bone metastases and no known visceral metastatic disease."

Also known as

Alpharadin, Ra-223, Radium Ra 223 dichloride, Radium-223 chloride.