Radium-223 dichloride for the treatment of metastatic prostate cancer.

INTRODUCTION: Bone metastases are a frequent complication of many malignancies and are particularly common in metastatic prostate cancer, where they are associated with a high degree of morbidity. Until recently, treatments relied on palliative bone targeting measures with no proven survival-prolonging action or on systemic agents with general anti-prostate cancer activity but significant toxicities. Radium-223 dichloride is a bone-seeking, α-emitting, radionuclide that has recently been licensed in the US and Europe for the treatment of men with castration-resistant prostate cancer, bone metastases and no known visceral metastases. Radium-223 is the first bone-seeking radionuclide therapy proven to result in increased overall survival versus placebo. AREAS COVERED: The existing market of bone-targeted agents is reviewed before considering what radium-223 adds by examining its pharmacology, pharmacokinetics and clinical efficacy and safety data. Initial relevant papers were identified by searching PubMed using combinations of the terms, 'Radium', 'Prostatic neoplasms', 'Bone', 'Neoplasm metastasis'. EXPERT OPINION: Consideration is given to further preclinical work needed into the mechanism of action of radium-223 and future clinical directions of the drug including combinations with other agents.