Clarity Pharmaceuticals to Begin Phase 3 Trial for New PSMA PET Agent for Prostate Cancer

Following a positive end of phase meeting with the Food and Drug Administration (FDA), Clarity Pharmaceuticals will proceed to a phase 3 prospective multicenter trial for further assessment of the prostate-specific membrane antigen (PSMA) positron emission tomography (PET) diagnostic agent ⁶⁴Cu SAR-bisPSMA to diagnose prostate cancer.

Clarity Pharmaceuticals said the goal of the prospective, open-label, non-randomized trial is to evaluate 64Cu SAR-bisPSMA for detecting prostate cancer in pelvic lymph nodes. Slated to begin patient enrollment in late 2023, the phase 3 CLARIFY trial is expected to involve 383 people with high-risk prostate cancer who will be having a radical prostatectomy with pelvic lymph node dissection, according to Clarity Pharmaceuticals.

Alan Taylor, Ph.D., said “compelling” pre-clinical and clinical trial results warranted further phase 3 trial exploration of ⁶⁴Cu SAR-bisPSMA PET, which may provide a viable alternative to the “low uptake and washout” of first-generation PSMA agents.

“The positive results from our completed PROPELLER trial showed that ⁶⁴Cu SAR-bisPSMA is safe, and its uptake in PSMA-expressing cancer lesions was significantly higher compared to the approved standard-of-care PSMA imaging agent for (prostate cancer) in Australia and the (United States),” said Dr. Taylor, the executive chairperson of Clarity Pharmaceuticals. “This may enable diagnosis of additional and smaller lesions, especially when coupled with the opportunity for delayed imaging, a characteristic not available to the first generation of PSMA imaging agents that exhibit high specificity but low sensitivity in diagnosing metastases outside of the prostate.”