Study of Abiraterone Acetate or Enzalutamide, Atezolizumab, GnRH Analog and Radiation Therapy in Men With Newly Diagnosed Hormone-sensitive Prostate Cancer

This study is to find out whether adding the study drug atezolizumab and stereotactic body radiotherapy (SBRT) to standard treatment with abiraterone acetate, prednisone, and Lupron® (leuprolide) is a safe and effective way to treat previously untreated metastatic prostate cancer, and to see whether the study treatment works better than the standard treatment.