Dr. Plimack Discusses Trials Investigating Apalutamide, Enzalutamide in M0 CRPC

Elizabeth Plimack, MD, director of Genitourinary Clinical Research at Fox Chase Cancer Center, discusses 2 studies reported at the 2018 Genitourinary Cancers Symposium in patients with nonmetastatic M0 castration-resistant prostate cancer (CRPC).

These patients show no evidence of metastatic disease on conventional imaging, but their PSA continues to rise, despite receiving androgen deprivation therapy, Plimack explains.

The phase III randomized, double-blind PROSPER study investigated enzalutamide (Xtandi) in these patients, and the phase III randomized, double-blind SPARTAN study looked at apalutamide (ARN-509).

Both trials showed a robust effect in terms of delay in time to metastases, but overall survival data have not yet shown a difference in treating early versus treating later. The question that remains is whether there is ultimately a long-term benefit in treating these patients earlier, in the M0 space, versus later, at M1, Plimack says.