Clinical stage radiopharmaceutical company Clarity Pharmaceuticals (ASX: CU6) is preparing to commence a pivotal Phase III trial of its 64Cu SAR-bisPSMA diagnostic in prostate cancer (PC) following a successful end of phase meeting with the US Food and Drug Administration (FDA).
The trial will be named CLARIFY (Positron Emission Tomography using 64Cu SAR-bisPSMA in participants with high-risk PC prior to radical prostatectomy: A prospective, single-arm, multi-centre, blinded-review, Phase III diagnostic performance study) and is expected to begin patient recruitment in late 2023.
The FDA is supportive of a prospective, non-randomised, single-arm, open-label, multi-center, Phase III diagnostic clinical trial of 64Cu SAR-bisPSMA PET in 383 participants with untreated, histopathology-confirmed PC, with high-risk features, who are proceeding to radical prostatectomy with pelvic lymph node dissection.
As a pivotal trial, the final study results are intended to provide sufficient evidence to support an application to the FDA for approval of 64Cu SAR- bisPSMA as a new diagnostic imaging agent in PC.
The aim of the Phase III trial is to assess the diagnostic performance of 64Cu SAR-bisPSMA PET to detect PC within the pelvic lymph nodes. Evaluation will be across 2 imaging timepoints, Day 1 (day of administration) and Day 2 (approximately 24 hours post administration).
We are very excited to progress our Phase III trial and are appreciative of the time and valuable guidance the FDA has provided in relation to our 64Cu SAR-bisPSMA program during the end of phase meeting,” Clarity’s Executive Chairperson, Dr Alan Taylor, said.
“The initiation of the CLARIFY trial is supported by compelling preclinical and clinical trial data. We would like to thank everyone who contributed to this exciting milestone, from our scientific collaborators at the University of Melbourne, who helped us overcome the low uptake and washout of first generation PSMA agents by assisting us in making an optimised PSMA agent for imaging and therapy, to the patients who participate in our clinical trials and to our incredible team and collaborators who work tirelessly towards our mutual goal of improving treatment outcomes for patients with PC.
“With this product, in both our diagnostic and therapy trials, we are now getting very close to achieving this goal.
“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 PC in Australia and the US.
“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.
“Furthermore, we believe that the additional shelf-life of up to 48 hours could not only allow clinics greater flexibility in scheduling of the scans, but also improve patients’ access to care in clinics and geographic areas where the short half-life of current PSMA PET tracers restricts the use of radiopharmaceuticals.
“We look forward to opening our Phase III trial later this year to confirm and build on the positive data we have seen on the 64Cu SAR-bisPSMA product to date. Our hope is that better diagnostic tools will help clinicians determine the best course of treatment for their patients, informing a potential life-changing decision between the surgical removal of the prostate and other treatment options that may support a better quality of life post-treatment.
“We are excited about further exploring these clinical benefits as well as the logistical and manufacturing advantages of our Targeted Copper Theranostics (TCTs) platform and bringing this next generation PSMA diagnostic to PC patients around the world.”
