Radium-223 chloride: Extending life in prostate cancer patients by treating bone metastases.
The treatment scope for patients with metastatic castrate-resistant prostate cancer (mCRPC) is rapidly expanding. On May 15, 2013, the U.S. Food and Drug Administration (FDA) approved radium-223 chloride ((223)RaCl2) for the treatment of mCRPC patients whose metastases are limited to the bones. Radium-223 is an α-emitting alkaline earth metal ion, which, similar to calcium ions, accumulates in the bone. In a phase III study (ALSYMPCA), mCRPC patients with bone metastases received best standard-of-care treatment with placebo or (223)RaCl2. At a prespecified interim analysis, the primary endpoint of median overall survival was significantly extended by 3.6 months in patients treated with radium-223 compared with placebo (P < 0.001). The radioisotope was well tolerated and gave limited bone marrow suppression. (223)RaCl2 is the first bone-targeting antitumor therapy that received FDA approval based on a significant extended median overall survival. Further studies are required to optimize its dosing and to confirm its efficacy and safety in cancer patients.
Authors' Affiliations: Departments of Clinical Oncology, Radiology, and Urology, Leiden University Medical Centre, Leiden, the Netherlands.
Michel D
MD
Wissing
Fijs W B
FW
van Leeuwen
Gabri
G
van der Pluijm
Hans
H
Gelderblom
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000556:secondary*; D002986:Clinical Trials as Topic; D017277:Drug Approval; D004353:Drug Evaluation, Preclinical; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D011868:Radioisotopes / Q000494:pharmacology / Q000627:therapeutic use; D011883:Radium / Q000494:pharmacology / Q000627:therapeutic use*
D000970:Antineoplastic Agents; D011868:Radioisotopes; C581106:radium Ra 223 dichloride; D011883:Radium