Study Comparing 177Lu-PSMA-617 and 225Ac-PSMA-617 Radioligand Therapies in High-Risk Prostate Cancer Patients Undergoing Prostatectomy

What this Trial Is About

Researchers are studying men with high or very high-risk localized or locoregional prostate cancer who plan to undergo prostatectomy. The trial compares two types of radioligand therapies Actinium-225 Prostate-Specific Membrane Antigen 225Ac-PSMA and Lutetium-177 Prostate-Specific Membrane Antigen 177Lu-PSMA. The goal is to evaluate differences in how these treatments work and their effects on the tumor and immune response before surgery. Participants will be assigned to one of two groups receiving 177Lu-PSMA-617 or 225Ac-PSMA-617. Each group includes subgroups receiving treatments intravenously or intra-arterially, with some receiving one dose and others two doses over six weeks. All participants in these groups will have prostatectomy about four weeks after completing radioligand therapy. A control group will undergo prostatectomy without prior radioligand treatment. Those receiving therapy will be monitored for safety six weeks after surgery and followed for up to 60 months control group participants will be followed for 24 months. During the study, participants will undergo blood sample collection, imaging scans including PSMA PET and SPECTCT, and prostate tissue collection at surgery for research comparisons. Researchers will measure tumor absorbed radiation dose, immune cell infiltration, prostate specific antigen PSA response, and pathologic response. Safety, side effects, quality of life related to dry mouth, and long-term outcomes will be assessed. The study includes detailed follow-up visits to monitor health and changes over time.

Comparison of 177Lu-PSMA-617 and 225Ac-PSMA-617