Utility of novel androgen receptor therapies in the real world: A nuanced approach

• Abiraterone and enzalutamide have great efficacy in metastatic castrate-resistant prostate cancer.
• Only radiographic progression or drug intolerance should guide when to stop abiraterone or enzalutamide.
• Given cross-resistance between abiraterone and enzalutamide, docetaxel should remain a standard consideration after progression.
• Resistance mechanisms to abiraterone and enzalutamide are outlined here.

Abiraterone and enzalutamide are in widespread clinical use because of their favorable safety and efficacy. Nonetheless, even with newer agents, resistance develops overtime. In this review, we discuss mechanisms of resistance to these newer agents as well as novel therapeutic agents. We also review the literature to help clinicians decide which agent to begin with and when to stop or switch androgen receptor agents.