Radiopharmaceutical developer Clarity Pharmaceuticals is highlighting the completion of the second cohort, as well as the advancement to the third cohort in the dose escalation phase of its phase I/II theranostic trial, SECuRE.
The trial is evaluating the performance of copper-64 (Cu-64)/copper-67 (Cu-67) SAR-bisPSMA in patients with metastatic castration-resistant prostate cancer (mCRPC). The trial is a multicenter, single-arm, dose-escalation trial with a cohort expansion involving up to 44 patients in the US. The goal is to determine the safety and efficacy of Cu-67 SAR-bisPSMA for the treatment of prostate cancer.
The second cohort of the dose escalation, where three participants received a single administration of 8 GBq of Cu-67 SAR-bisPSMA, has been completed. Clarity said no dose-limiting tissues have been reported in any of the patients dosed to date and that the trial's progression to the third cohort will see a dose increase to 12 GBq.
Clarity also said the third cohort will be the last to assess single doses of Cu-67 SAR-bisPSMA and will be followed by a multi-dose cohort, pending safety evaluation. All three participants in the second cohort remain on the trial and are showing a prostate-specific antigen reduction, with two of the three showing an initial reduction of around 90%. The company said that a decline of 50% or greater is one of the primary endpoints of the trial.
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