Checkpoint Inhibitors and SBRT for MCRPC

The participants receive treatment for 52 weeks, including four cycles of ipilimumab and nivolumab with or without concomitant SBRT (24 Gray in three fractions) to a single soft tissue or bone metastasis, followed by 10 cycles of nivolumab. Participants are followed until progression, death, or for 12 months after the end of treatment. Biopsies from metastatic sites are collected at baseline, before the third treatment, and at the end of treatment. Blood sampling for immune monitoring and circulating tumor DNA is performed consecutively at baseline and every radiographic assessment.