Lutetium-177 (Lu177) Prostate-Specific Antigen (PSMA)-Directed EndoRadiotherapy

Upon inclusion patients were randomized in a 1:1 ratio into two treatment doses. Radioligand therapy (RLT) were performed by repeated intravenous (i.v.) injection of 6.0 gigabecquerel (GBq) (+/- 10%) or 7.4 GBq (+/- 10%) 177Lu-PSMA-617 every 8+/- 1 weeks until reaching four cycles or threshold maximum dose to the kidneys of 23 Gray (Gy). All doses after labeling were presented in buffered solution for i.v. injection. In the initial plan for the study design a total of 200 patients with histologically proven prostate cancer and metastatic castration-resistant prostate cancer (mCRPC) were to be enrolled, however due to early stopping of enrollment only 71 patients were enrolled at time of data base lock. Each patient underwent a screening visit within 14 days prior to receiving study drug. Treatment was continued until either of the following conditions applied: * Prostate-specific antigen (PSA)/radiographic progression at \>= 12 weeks * Completion of four RLT cycles * 23 Gy kidney dose would be exceeded by the next cycle as estimated by dosimetry * Patient withdrawal (e.g. appearance of intolerable adverse events).