Study of 177Lu-PSMA-617 In Metastatic Castrate-Resistant Prostate Cancer in Japan

This study is an open label, multicenter, single arm, phase II study to evaluate the efficacy, tolerability, safety, PK and dosimetry of 177Lu-PSMA-617 in participants with progressive PSMA-positive mCRPC in Japan. Furthermore, the safety, PK, and dosimetry of 68Ga-PSMA-11 (PSMA imaging agent) are also evaluated in this study. This study consists of two populations: 1. Post-taxane population: The post-taxane population will include men with PSMA-positive mCRPC who received at least one ARDT (for example enzalutamide, abiraterone etc.) and were previously treated with at least one, but no more than two taxane regimens. Participants treated with only 1 prior taxane regimen are eligible if the participant's physician deems the participants unsuitable to receive a second taxane regimen. 2. Pre-taxane population; The pre-taxane population will include men with PSMA-positive mCRPC who were previously treated with one ARDT as last treatment and have not been exposed to a taxane-containing regimen in the CRPC or HSPC settings and for whom it is considered appropriate to delay taxane-based chemotherapy. This is a 4-part study: Part 1 (a safety run-in part), Part 2 (post-taxane part), Part 3 (pre-taxane part) and Part 4 (expanded trial part). 1. Part 1 (safety run-in part) will confirm the tolerability and safety of recommended regimen, once every 6-weeks, 7.4 GBq of the 177Lu-PSMA-617. Minimum of 3 participants as 177Lu-PSMA-617 tolerability evaluable participants will be enrolled. Dosimetry and PK assessments of 177Lu-PSMA-617 are mandatory for participants enrolled in this part. 2. Part 2 (post-taxane part) will evaluate the efficacy, safety, PK and dosimetry of 177Lu-PSMA-617 plus BSC/BSoC, as well as safety, PK, and dosimetry of 68Ga-PSMA-11 in post-taxane participants with PSMA-positive mCRPC. 3. Part 3 (pre-taxane part) will evaluate the efficacy, safety, PK and dosimetry of 177Lu-PSMA-617, as well as safety, PK, and dosimetry of 68Ga-PSMA-11 in taxane naïve participants with PSMA-positive mCRPC 4. Part 4 (expanded trial part) will provide humanistic perspective access of study treatment (68Ga-PSMA-11 and 177Lu-PSMA-617) for the Japanese post-taxane participants with PSMA-positive mCRPC until marketed products are available in Japan. Additional safety and efficacy of 68Ga-PSMA-11 and of 177Lu-PSMA-617 will be evaluated. Additionally, PK and dose rate will be evaluated (PK is optional and dose rate is mandatory in Part 4). Approximately 80 eligible participants will be enrolled in Part 4 and approximately 10 evaluable participants PK data will be collected. This study will consist of 3 periods: screening period, treatment period, and long term follow up. The long-term follow-up ends after participant transitions to a post marketing trial.