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 is used to treat bone metastases, a common problem for men living with metastatic hormone resistant prostate cancer (MHRPC), affecting up to 90% of these patients. The development of a drug called radium-223 (brand name: Xofigo) is a substantial innovation, not only because it causes less toxicity compared to its predecessors, but also because it prolongs life.