Clarity Pharmaceuticals (ASX:CU6) received a fast track designation from the US Food and Drug Administration for its imaging agent Copper-67-SAR-bisPSMA for the potential treatment of adult patients with prostate-specific membrane antigen-positive metastatic castration-resistant prostate cancer who have been previously treated with androgen receptor pathway inhibition, according to a Wednesday Australian bourse filing.

Clarity earlier received two fast track designations for the diagnostic Copper-64-SAR-bisPSMA in prostate cancer patients.

The designation was granted based on the preliminary results to date from the phase 1 and 2a study, which is investigating the safety and efficacy of copper-67-SAR-bisPSMA for the treatment of prostate cancer patients.

It will allow for a faster review process once Clarity submits its product approval applications, per the filing.

The trial is currently advancing through the highest dose group where participants were administered multiple doses of 12 gigabecquerels of copper-67-SAR-bisPSMA and recruitment into the fourth group has been completed.

SAR-bisPSMA connects two prostate-specific membrane antigen-targeting agents to the firm's proprietary sarcophagine technology which securely holds copper isotopes.

The firm's shares rose almost 3% in recent trading on Wednesday.