Highlights
IND approval received for SAR-Bombesin product, enabling a Phase II "SABRE" imaging trial to detect prostate cancer in up to 50 PSMA-negative participants in the US
Approximately 20% of prostate cancer patients with biochemical recurrence (BCR) are PSMA-PET negative and therefore unsuitable for the currently approved PSMA targeting agents, presenting an opportunity to target these cancers with Clarity's SAR-Bombesin product
SYDNEY, June 6, 2022 /PRNewswire/ -- Clarity Pharmaceuticals (ASX: CU6) ("Clarity"), a clinical-stage radiopharmaceutical company developing next-generation products to address growing medical needs in oncology, announces the approval of its Investigational New Drug (IND) application by the United States Food and Drug Administration (US FDA) to evaluate its SAR-Bombesin product as an imaging agent in prostate cancer patients that are Prostate-Specific Membrane Antigen (PSMA)-negative.
Clarity's Executive Chairman, Dr Alan Taylor, commented, "Receiving clearance from the FDA on the imaging trial with SAR-Bombesin is yet another significant milestone for Clarity. It shows our ability to develop cutting-edge theranostics from the lab, through preclinical studies and into clinical trials, with SAR-Bombesin being Clarity's fourth IND across five products which are clear for investigation in the US."
This IND gives Clarity clearance to proceed with a US-based Phase II 64Cu SAR-Bombesin Positron Emission Tomography (PET) imaging trial in participants with PSMA-negative biochemical recurrence (BCR) of prostate cancer following definitive therapy (such as surgery or radiation).
SABRE, which derives from "Copper-64
SAR-Bombesin in
Biochemical
REcurrence of Prostate Cancer trial", is a multi-center, single arm, non-randomised, open-label trial in up to 50 PSMA-negative patients with known or suspected prostate cancer. The primary objectives of the trial are to investigate the safety and tolerability of 64Cu SAR-Bombesin, as well as its ability to correctly detect the recurrence of prostate cancer.
The SABRE trial builds upon the promising clinical data from the pilot trial assessment of 64Cu SAR-Bombesin in breast cancer led by Prof Louise Emmett of St Vincent's Hospital Sydney. The data from this trial was recently presented at the prestigious American Society of Clinical Oncology (ASCO) 2022 Annual Meeting. The SABRE trial was developed in response to the strong demand for this product from clinicians with prostate cancer patients whose cancer was not visible with currently approved PSMA diagnostic agents or conventional imaging (such as CT and/or MRI). Their patients were successfully imaged with 64Cu SAR-Bombesin under a Special Access Scheme.
Approximately 20% of prostate cancers with BCR are PSMA-PET negative1-4. These patients are therefore unlikely to respond to therapeutic PSMA-targeted products and currently have few treatment options available to them. Given the prostate cancer indication is one of the largest in oncology, there is a significant unmet medical need in this segment. The SAR-Bombesin product targets the Gastrin Releasing Peptide receptor (GRPr) found on prostate and many other cancers. As such, the product could offer valuable imaging and therapeutic options for not only PSMA negative patients, but also the large number of patients that have the target receptor on their cancers.
"We look forward to further progressing the development of SAR-Bombesin and hope it will provide a new and effective diagnostic option for prostate cancer patients. Building on the promising clinical and preclinical data acquired to date, we are also planning an IND submission for a theranostic trial in prostate cancer participants, using 67Cu SAR-Bombesin therapy paired with the imaging agent, 64Cu SAR-Bombesin. Combined with the clinical, environmental and logistical benefits enabled by the copper isotope pairing, SAR-Bombesin has potential to provide this large patient population with accurate and precise detection and treatment of prostate cancer. We anticipate the SABRE trial to commence shortly and the theranostic trial to commence in 2023," Dr Taylor added.
This announcement has been authorised for release by the Executive Chairman.
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About Clarity Pharmaceuticals
Clarity is a clinical stage radiopharmaceutical company focused on the treatment of serious disease. The Company is a leader in innovative radiopharmaceuticals, developing targeted copper theranostics based on its SAR Technology Platform for the treatment of cancer in children and adults.
About SAR-Bombesin
SAR-Bombesin is a highly targeted pan-cancer radiopharmaceutical with broad cancer application. It targets the gastrin-releasing peptide receptor (GRPr) present on cells of a range of cancers, including but not limited to prostate, breast and ovarian cancers. GRPr is found in approximately 75-100% of prostate cancers, including prostate cancers that don't express PSMA (PSMA-negative)5-9. The product utilises Clarity's proprietary sarcophagine (SAR) technology that securely holds copper isotopes inside a cage-like structure, called a chelator. Unlike other commercially available chelators, the SAR technology prevents copper leakage into the body. SAR-Bombesin is a Targeted Copper Theranostic (TCT) that can be used with isotopes of copper-64 (Cu-64 or 64Cu) for imaging and copper-67 (Cu-67 or 67Cu for therapy).
About Prostate Cancer
Prostate cancer is the second most common cancer diagnosed in men globally and the fifth leading cause of cancer death worldwide10. The National Cancer Institute estimates in 2022 there will be 268,490 new cases of prostate cancer in the US and around 34,500 deaths from the disease11.
References
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Reubi JC, Wenger S, Schmuckli-Maurer J, Schaer JC, Gugger M. Bombesin receptor subtypes in human cancers: detection with the universal radioligand (125)I-[D-TYR(6), beta-ALA(11), PHE(13), NLE(14)] bombesin(6-14). Clin Cancer Res. 2002;8(4):1139-1146.
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Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries
American Cancer Society, Cancer Statistics Center,
SOURCE Clarity Pharmaceuticals
