A Study of Talazoparib With or Without Enzalutamide in People With Prostate Cancer Who Have Previously Received Abiraterone Acetate

This study is comparing two treatment approaches for men with prostate cancer that has stopped responding to a hormone-blocking therapy called abiraterone acetate: one group receives a PARP inhibitor called talazoparib plus enzalutamide (a hormone therapy), and the other receives talazoparib alone. **You may be eligible if...** - You are 18 or older with a diagnosis of prostate cancer - Your cancer previously received treatment with abiraterone acetate - Your cancer has progressed (worsened) despite that treatment **You may NOT be eligible if...** - You have had certain prior cancer therapies that conflict with the study drugs - You have significant heart problems or uncontrolled other medical conditions - You have bone fracture risks that are unmanaged - Your cancer has spread to the brain Talk to your doctor to see if this trial is right for you.