Radium-223 Dichloride, otherwise known as Xofigo, is the first alpha-emitting radiopharmaceutical used to treat prostate-cancer-related bone metastasis. The FDA approved Xofigo in May of 2013. The clinical trial that led to the FDA approval was called the ALSYMPCA trial. Eligible patients were randomized in a 2:1 fashion to either receive six monthly intravenous injections of radium-223 or best standard of care, such as antiandrogen hormonal therapy, local external beam radiation, corticosteroids, estramustine, or ketoconazole. The men who received radium-223 had improvement in bone pain and also experienced an increased survival.

Radium-223 (or Alpharadin) is a new targeted alpha-emitting agent which has shown a prolongation of survival in castrate-resistant prostate cancer patients with bone-metastatic disease (5).