Dr. Robert Dreicer on Overcoming Resistance Pathways in mCRPC

Robert Dreicer, MD, associate director for Clinical Research and deputy director of the University of Virginia Cancer Center, discusses next-generation antiandrogen therapies in metastatic castration-resistant prostate cancer (mCRPC).

Antiandrogen therapies have been around for several years, and one of the striking findings that all clinicians deal with is the cross-resistance to both enzalutamide and abiraterone, says Dreicer.

This is a major clinical dilemma, and while multiple resistance pathways have been recognized, nothing has been able to predict cross-resistance using any of the assays available—including AR-V7, probably the most well-defined resistance pathway, says Dreicer.

Oncologists must then make clinical judgments about when a patient might go from one drug to another, and that might depend on prior response, clinical setting, or whether the patient is symptomatic. Predictive biomarkers need to be identified to really give us data-driven ways to make decisions.

It was disappointing earlier this year when the trial of galeterone—which was an agent that was hoped to be able to overcome AR-V7 resistance—was stopped prematurely, says Dreicer. However, there are other next-generation compounds in development, and the AR-V7 assay is moving its way to commercialization. This is an area that has active research ongoing.