• Another participant with metastatic castration-resistant prostate cancer achieved undetectable disease after 67Cu-SAR-bisPSMA treatment
• Undetectable PSA after first cycle, negative PSMA PET after second cycle
• All related adverse events were mild and resolved, no haematological or renal AEs

Clarity Pharmaceuticals (ASX: CU6) announces that another participant with metastatic castration-resistant prostate cancer (mCRPC) in the Cohort Expansion Phase (Phase II) of the SECuRE trial achieved undetectable disease as assessed by prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) positron emission tomography (PET). The undetectable PSA was measured following the first cycle and the negative PSMA PET was reported following the second cycle of 67Cu-SAR-bisPSMA (8 GBq each cycle). The participant is a 76-year-old man who was initially diagnosed with prostate cancer 15 years ago and had metastatic disease since 2020. Previous systemic anti-cancer treatments included an androgen receptor pathway inhibitor (ARPI) and androgen deprivation therapy (ADT). All related adverse events (AEs) were mild (Grade 1), most of which resolved after the treatment. No haematological or renal AEs were observed to date. This is the fifth patient to achieve undetectable disease by radiographic assessment following 67Cu-SAR-bisPSMA treatment. The previous participant in the same Cohort Expansion Phase who achieved undetectable PSA after three cycles of 8 GBq 67Cu-SAR-bisPSMA continues to demonstrate undetectable disease on PSMA PET after the fourth cycle. The SECuRE trial will continue enrolment into the Cohort Expansion Phase with planned completion of recruitment in 2026. Phase III registrational trial planning is ongoing based on data generated to date.

The momentum of data we are generating with our lead SAR-bisPSMA product in both theranostic and diagnostic trials is strong, with excellent results to date on all fronts. We now look forward to progressing the SECuRE trial recruitment and have already initiated the planning for a registrational Phase III trial, as we hope to see more people benefit from our unique theranostic product.