64Cu-SAR-bisPSMA Detects 2.6x More Lesions, Gains Spotlight at ASCO GU and AUA 2025

Clarity’s Diagnostic Innovation Gains Global Recognition

Clarity Pharmaceuticals (ASX: CU6) has secured a significant milestone with the acceptance of two abstracts detailing its COBRA and CLARIFY clinical trials for presentation at the prestigious American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU) 2025. Additionally, an abstract from the COBRA trial will be showcased at the American Urological Association (AUA) Annual Meeting 2025. These forums represent some of the most influential gatherings in oncology and urology, underscoring the growing international interest in Clarity’s novel diagnostic agent, 64Cu-SAR-bisPSMA.

The presentations will focus on the diagnostic superiority of 64Cu-SAR-bisPSMA, a radiopharmaceutical designed to target prostate-specific membrane antigen (PSMA) with enhanced sensitivity. The data reveal that this agent identifies prostate cancer lesions earlier and in greater numbers than currently approved PSMA PET imaging agents, which have known sensitivity limitations.

Clinical Trial Insights: COBRA and CLARIFY

In the COBRA trial, 64Cu-SAR-bisPSMA demonstrated remarkable diagnostic performance. Among a subset of patients undergoing follow-up standard-of-care (SOC) PSMA PET imaging, 64Cu-SAR-bisPSMA detected positive scans in 70% of participants on same-day imaging and 90% on next-day imaging, compared to just 60% detection with SOC PET, which is limited to same-day imaging. The agent identified an average of 26.3 lesions on same-day and 52.6 on next-day imaging, significantly outpacing the 20 lesions detected by SOC PET.

Importantly, 64Cu-SAR-bisPSMA detected lesions as small as 2 mm and identified cancerous lesions up to six months earlier than SOC agents. Histopathological confirmation validated the presence of prostate cancer in up to 78% of biopsied lesions identified by 64Cu-SAR-bisPSMA, a substantial improvement over less sensitive imaging methods. Notably, 100% of lesions outside the prostate bed were confirmed positive, highlighting the agent’s precision in challenging diagnostic contexts.

Implications for Patient Care and Treatment Decisions

The clinical impact of these findings is profound. Investigators reported that nearly half (48%) of treatment plans were altered based on the enhanced imaging results from 64Cu-SAR-bisPSMA. This suggests that earlier and more accurate lesion detection could lead to more tailored and potentially more effective therapeutic strategies for prostate cancer patients.

Dr Alan Taylor, Clarity’s Executive Chairperson, emphasized the transformative potential of SAR-bisPSMA, noting its dual-targeting bis structure and the advantage of next-day imaging enabled by the copper-64 isotope’s longer half-life. This combination not only improves diagnostic accuracy but also expands clinical flexibility, potentially setting a new standard in prostate cancer imaging.

Next Steps and Regulatory Outlook

Building on the COBRA and PROPELLER trial data, Clarity is preparing to launch the AMPLIFY registrational trial targeting patients with biochemical recurrence of prostate cancer. Alongside the ongoing CLARIFY trial, which is actively recruiting across more than 20 sites in the U.S. and Australia, these studies aim to support U.S. FDA approval of 64Cu-SAR-bisPSMA for both newly diagnosed and recurrent prostate cancer cases.

While 64Cu-SAR-bisPSMA remains an unregistered product pending regulatory review, its safety profile has been reassuring, with only mild and transient adverse events reported among trial participants. The company’s SAR technology platform, which securely chelates copper isotopes to prevent leakage, further strengthens the therapeutic promise of this targeted copper theranostic approach.

As prostate cancer remains the second most common cancer in men worldwide and a leading cause of cancer death, Clarity’s advancements could have far-reaching implications for diagnostics and patient outcomes globally.