Radium-223 Safety, Efficacy, and Concurrent Use with Abiraterone or Enzalutamide: First U.S. Experience from an Expanded Access Program

In this phase II U.S. expanded access program, radium-223 was well tolerated, with a median overall survival of 17 months in metastatic castration-resistant prostate cancer patients. In post hoc analyses, radium-223 was safe regardless of concurrent abiraterone or enzalutamide, and median overall survival appeared longer when radium-223 was used earlier in patients with less prior treatment. Patients with more advanced disease were less likely to benefit from radium-223. Clinicians should consider baseline clinical characteristics and therapy sequence to provide the greatest clinical value to patients.