IND Application for PSMA Theranostics Gets FDA Okay

The US Food and Drug Administration (FDA) has cleared Clarity Pharmaceuticals’ Investigational New Drug (IND) application for a study of Prostate-Specific Membrane Antigen (PSMA) positive prostate cancers using the company’s 64Cu-SAR- bisPSMA and 67Cu-SAR-bisPSMA.

The SECuRE trial (Systemic Cu theranostics in prostate cancer) is a Phase I/IIa study for identification and treatment of PSMA-expressing metastatic castrate resistant prostate cancer (mCRPC), which will be conducted in the U.S. (NCT04868604)[1]. It is a theranostic multi-center, single arm, dose escalation study with a cohort expansion planned for up to 44 patients. The trial employs diagnostic Positron Emission Tomography imaging with 64Cu-SAR-bisPSMA for selection of patients suitable for therapy cycles with 67Cu-SAR-bis-PSMA.

Clarity's SAR-bisPSMA product utilizes two isotopes of copper, and is therefore not constrained by production of therapeutic isotopes from nuclear reactors. The therapeutic product utilizes copper-67, which is being produced domestically in the USA on electron accelerators, avoiding the issues commonly associated with the production of isotopes on nuclear reactors. The diagnostic product utilizes copper-64, which is regularly produced in significant volumes on cyclotrons in the US, and has a half-life of 12.7 hours, avoiding the short half- life issues of other diagnostic isotopes. Both the diagnostic and therapeutic products can be centrally manufactured and shipped as finished product direct to the treatment centers, which removes the need for dedicated radiopharmacy facilities at treatment centers.

Dr Alan Taylor, Clarity's Executive Chairman, commented on the IND approval, "The FDA response suggests not only the importance of developing novel treatments for men with late- stage prostate cancer, whose prognosis is currently very poor, but also validates Clarity's copper pairing paradigm and the centralised manufacturing concept, which differentiates it from the competitor products and enables product supply to the levels suitable for use in large patient indications.

"We are very excited to commence the SECuRE trial in mCRCP patients and have engaged a world class group of key opinion leaders in the prostate cancer space to support the development of 64/67Cu SAR-bisPSMA. Clarity's Global Clinical Development Group has unrivalled experience in the commercialization of the only currently approved radiotherapeutic for prostate cancer. The FDA response is a crucial milestone in the development of SAR- bisPSMA theranostics and we are looking forward to progressing this trial at some of the leading cancer centers in the US as part of our ultimate goal of developing better treatments for children and adults with cancer," said Dr Taylor.