Dr. Maughan on Enzalutamide Plus Radium-223 in mCRPC

Benjamin Maughan, MD, PharmD, instructor, Division of Medical Oncology, Huntsman Cancer Institute, discusses enzalutamide (Xtandi) plus radium-223 (Xofigo) in metastatic castration-resistant prostate cancer (mCRPC).

Safety data from the phase II randomized trial of radium-223 dichloride plus enzalutamide versus enzalutamide alone in mCRPC were presented at the 2018 ASCO Annual Meeting. These results showed that the combination is safe and active, particularly in patients with progressive mCRPC. There was no difference in serious adverse events between the combination and single-agent enzalutamide.

The primary safety analysis was based on the increase of cytopenias, and although the combination had a higher rate of cytopenias, Maughan said that was not unexpected. However, the incidence of cytopenias in this study was less than what was seen in ALSYMPCA, which was a phase III study of single-agent radium-223 in patients with symptomatic hormone-refractory prostate cancer with skeletal metastases.