The PROSPER study (NCT02003924) is a Phase III, randomized trial of enzalutamide in nonmetastatic castration-resistant prostate cancer (nmCRPC). The primary analysis of the study confirmed a clinically significant improvement in metastasis-free survival (MFS) in nmCRPC patients with the agent being trialled. Here, Ugo De Giorgi, MD, PhD, of the IRCCS, Meldola, Italy, discusses results from the post-hoc analysis of the study by prior therapy. This video was recorded at the 2019 Genitourinary Cancers Symposium, held in San Francisco, CA.