Dr. Vogelzang on Sequencing Abiraterone and Enzalutamide

Nicholas J. Vogelzang, MD, member of the US Oncology Network, site research leader for Comprehensive Cancer Centers of Nevada, professor of medicine at the University of Nevada School of Medicine, discusses sequencing abiraterone acetate (Zytiga) and enzalutamide (Xtandi) in the treatment of men with metastatic castration-resistant prostate cancer (CRPC).

Overall, Vogelzang remarks that very little data is available on the optimal sequence for newer agents approved to treat CRPC. Particularly since the clinical trials investigating these agents were completed in a very quick timeframe.

In the post-chemotherapy setting, as abiraterone gained approval, the trial examining enzalutamide finished accrual. Also, in the pre-chemotherapy space, abiraterone was approved and available to treat patients who were enrolling on the trial investigating enzalutamide in this setting.

The administration of abiraterone directly before treatment with enzalutamide may have an affect on outcomes, Vogelzang postulates. Without adequate data, at this point, it is currently unknown if abiraterone is cross resistant with enzalutamide. In general, these agents should work synergistically, based on their mechanism of actions, but biology tends to be more complicated, Vogelzang adds.