Cabazitaxel Versus the Switch to Alternative AR-targeted Agent (Enzalutamide or Abiraterone) in Metastatic Castration-resistant Prostate Cancer (mCRPC) Patients Previously Treated With Docetaxel and Who Rapidly Failed a Prior AR-targeted Agent

Primary Objective: To compare the radiographic progression-free survival (rPFS) (using Response Evaluation Criteria in Solid Tumors \[RECIST\] 1.1 for tumor lesions and Prostate Cancer Working Group 2 (PCWG2) criteria for bone scan lesions or death due to any cause) with chemotherapy (cabazitaxel plus prednisone, Arm A) versus Androgen Receptor (AR)-targeted therapy (enzalutamide or abiraterone acetate plus prednisone, Arm B) in mCRPC participants who have been treated with docetaxel and who had disease progression while receiving AR-targeted therapy within 12 months of AR treatment initiation (less than or equal to \[\<=\]12 months, either before or after docetaxel). Secondary Objective: * To compare efficacy for: * Prostate-specific antigen (PSA) response rate and time to PSA progression (TTPP). * Progression-free survival (PFS). * Overall survival (OS). * Tumor response rate and duration of tumor response. * Pain response and time to pain progression. * Symptomatic skeletal event (SSE) rate and time to occurrence of any SSE. * Health status and Health-related Quality of Life (HRQOL). * To evaluate the correlation of a signature of resistance to AR-targeted agents with clinical outcome via the analysis of circulating tumor cell (CTC) phenotypes as well as expression and localization of proteins including AR isoforms in CTCs. * To evaluate safety in the 2 treatment arms.

The duration of the study per participant was approximately 2 years. Each participant was treated until radiographic disease progression, unacceptable toxicity, or participant's refusal of further study treatment, and each participant was followed after completion of study treatment until death, study cut-off date, or withdrawal of participant consent.