Radium-223 RA-223; Alpharadin is an α-emitting radiopharmaceutical that delivers high energy, short range irradiation that induces dsDNA breaks with lower penetration to surrounding tissues compared with the β-emitting (strontium-89 and samarium-153). In the study (ALSYMPCA), a Phase III trial tested radium in symptomatic patients who had previously received docetaxel or were otherwise unsuitable to receive chemotherapy. Patients were randomized 2:1 in favor of RA-223. The study treatment consisted of up to six intravenous administrations of RA-223 or placebo, each separated by an interval of 4 weeks. The primary end point of the study was overall survival. Secondary end points included time to occurrence of SREs and changes and time to progression in key bone markers associated with disease status (including serum levels of PSA and total alkaline phosphatase. At an updated analysis presented at the 2012 ASCO annual meeting the median OS benefit for RA-223 increased from 2.8 to 3.6 months, with a hazard ratio of 0.695 (i.e., 30.5% reduction in risk of death). RA-223 is an effective therapy that improves OS and time to first SRE with a highly favorable safety profile, and may provide a new standard of care for CRPC patients with bone metastasis.