U.S. FDA Approves 64Cu-SAR-bisPSMA Phase III Trial for Recurrent Prostate Cancer

The United States Food and Drug Administration (U.S. FDA) has given positive feedback on Clarity Pharmaceuticals' pivotal Phase III trial for the 64Cu-SAR-bisPSMA diagnostic, aimed at prostate cancer patients with biochemical recurrence (BCR). This study, named AMPLIFY, follows successful outcomes from earlier COBRA and PROPELLER trials. These earlier trials demonstrated significantly higher uptake and retention in lesions compared to standard-of-care (SOC) imaging. The trials also showed that next-day imaging detected a greater number of lesions than same-day imaging.

The AMPLIFY trial is set to involve around 220 prostate cancer patients in a non-randomised, single-arm, open-label, multi-centre Phase III trial. This is part of Clarity’s efforts to secure FDA approval for 64Cu-SAR-bisPSMA, targeting patients with confirmed prostate cancer pre-prostatectomy/pre-definitive treatment and those with BCR of prostate cancer. Recruitment for the AMPLIFY trial is expected to start in early 2025.

Clarity Pharmaceuticals, based in Sydney, is a clinical-stage company developing next-generation radiopharmaceutical products to improve treatment outcomes for cancer patients. The company's mission is to develop innovative products that enhance the detection and treatment of cancer in children and adults. Clarity announced the commencement of the AMPLIFY trial following a successful end-of-phase meeting with the U.S. FDA.

The AMPLIFY trial will use 64Cu-SAR-bisPSMA Positron Emission Tomography (PET) to detect prostate cancer recurrence in about 220 participants with rising or detectable PSA levels post-treatment. As a pivotal trial, the results are intended to support FDA approval for 64Cu-SAR-bisPSMA as a new diagnostic imaging agent for prostate cancer. The trial will evaluate the imaging capabilities of 64Cu-SAR-bisPSMA PET across two timepoints: same-day imaging on the day of administration and next-day imaging approximately 24 hours post-administration.

The launch of the AMPLIFY trial is backed by compelling data from previous studies, including the Phase I/II COBRA trial and the Phase I PROPELLER trial. These studies have been presented at major medical conferences like the Society of Nuclear Medicine and Molecular Imaging (SNMMI) Annual Meeting, the European Association of Nuclear Medicine (EANM) Congress, and the American Society of Clinical Oncology (ASCO) Annual Meeting. The data indicated that 64Cu-SAR-bisPSMA is safe and has higher uptake in PSMA-expressing cancer lesions compared to SOC PSMA imaging agents. Additionally, the COBRA trial data revealed that 64Cu-SAR-bisPSMA could detect smaller lesions than expected, including those less than 2 mm in diameter, and identify lesions months before they were detectable by SOC PSMA agents.

Dr. Alan Taylor, Clarity's Executive Chairperson, expressed excitement about the progress of their second Phase III trial with 64Cu-SAR-bisPSMA. He acknowledged the FDA's guidance and highlighted the favorable data seen so far for this product. Dr. Taylor believes that the 64Cu-SAR-bisPSMA offers clinical benefits and, with a shelf-life of up to 48 hours, could improve patient access to diagnostic tools, extending the use of radiopharmaceuticals to more clinical sites.

The AMPLIFY trial marks a significant milestone in Clarity's efforts, made possible through the hard work of their team and collaborators. The company expressed gratitude to the clinicians and patients involved in their clinical trials. Clarity looks forward to commencing recruitment for the AMPLIFY trial and continuing to build on the exceptional data seen to date. The company is committed to developing better diagnostic tools to help clinicians determine optimal treatment courses for prostate cancer patients, aiming to bring this next-generation PSMA diagnostic to patients globally.

64Cu-SAR-bisPSMA is a novel diagnostic agent derived from Clarity’s SAR technology, which securely holds copper isotopes inside a chelator structure. This technology prevents copper leakage into the body, enhancing the safety and efficacy of the diagnostic agent. Clarity is currently conducting a clinical development program to assess the efficacy and safety of 64Cu-SAR-bisPSMA, with the goal of making it commercially available in the future.