Talazoparib Plus Enzalutamide After Progression to Abiraterone in Metastatic Prostate Cancer: (TEAM PC)

The purpose of this clinical trial is to determine the anti-tumor activity of talazoparib plus enzalutamide as first line treatment for metastatic castration resistant prostate cancer (mCRPC) in participants whose disease has progressed on abiraterone. The main questions it aims to answer are: * Does talazoparib plus enzalutamide improve efficacy in metastatic castration resistant prostate cancer (mCRPC) compared to enzalutamide alone? * What is the time to disease progression \[radiographic, Prostate Specific Antigen (PSA), clinical\] in participants treated with talazoparib plus enzalutamide after progression on abiraterone? * What medical problems do participants have when receiving talazoparib plus enzalutamide? Researchers will compare the combination of talazoparib and enzalutamide as a first-line treatment for mCRPC to see if the combination improves the PSA response rate and delays progression compared to enzalutamide alone. The safety and tolerability of the combination (talazoparib and enzalutamide) will also be studied