ESMO 2021: PSMAfore: A Phase 3 Study to Compare 177Lu-PSMA-617 Treatment with a Change in Androgen Receptor Pathway Inhibitor in Taxane-Naïve Patients with mCRPC

( Lutetium-177 is a radioligand that when bound to a prostate-specific membrane antigen (PSMA) targeting molecule delivers beta-particle radiation to PSMA-expressing cells and their local microenvironment. This therapy depends on prostate cancer cell surface expression of PSMA. The phase 3 VISION trial demonstrated overall survival benefit with this treatment modality in mCRPC patients who had progressed on taxane chemotherapy as well as androgen pathway inhibition. In this abstract, Dr. Morris and colleagues present the PSMAfore trial (NCT04689828), testing Lutetium-177 in mCRPC prior to taxane chemotherapy.

Approximately 450 patients with mCRPC who (1) have progressed on at least 1 androgen pathway inhibitor and (2) have PSMA positive tumors as assessed by Gallium-68 PSMA PET scan will be randomized 1:1 to receive 177Lu-PSMA-617 (7.4 GBq i.v. every 6 weeks for 6 cycles) or a change in ARPI to either abiraterone or enzalutamide. Best supportive care is allowed in both arms. Patients will be stratified by prior androgen pathway inhibition in castration-resistant vs hormone-sensitive prostate cancer settings and pain symptomatology. The primary endpoint is radiographic progression-free survival according to PCWG3-modified RECIST v1.1 criteria. Cross-over from the control arm to the Lutetium-177 arm is allowed upon progression.

Presented by: Michael J. Morris, MD, Memorial Sloan Kettering Cancer Center

Written by: Alok Tewari, MD, PhD – Genitourinary Medical Oncologist, Instructor in Medicine, Dana-Farber Cancer Institute, Harvard Medical School, Twitter: @aloktewar during the 2021 European Society for Medical Oncology (ESMO) Annual Congress 2021, Thursday, Sep 16, 2021 – Tuesday, Sep 21, 2021.