A Phase I Trial of 61Cu-NODAGA-PSMA for Patients with Prostate Cancer

Overview

Molecular Imaging (MI) uses tracers which emit radiation to provide clinically valuable imaging for patient with cancer. Most current MI agents utilize Fluorine 18 or Gallium 68 as the positron emitter for PET imaging. However, these isotopes have short half-lives which limit the geographic distribution range of tracers made with these isotopes. Copper 61 (61Cu) has a 3.3 hour half-life, which would allow for far greater distribution range following radiotracer production. This phase I trial will test the safety and effectiveness of a novel MI radiotracer that uses 61Cu as its positron emitting isotope and targets Prostate Specific Membrane Antigen (PSMA) for imaging prostate cancer. A successful trial will provide the ability to advance this novel 61Cu-NODAGA-PSMA radioisotope into phase II trials, as well as open a new paradigm into the production of MI radioisotopes with 61Cu.

This is a phase 1, non-randomized study. Subjects will undergo imaging with 100-300 MBq (2.7-8.1 mCi) of 61Cu-NODAGA-PSMA intravenously (IV), followed by PET/CT imaging 60 (+/- 10) minutes post radiotracer administration. This is a diagnostic imaging study. As the imaging agent will not have a treatment effect, efficacy evaluations that are standard in treatment protocols will not be performed. We expect to enroll 6-10 patients in the proposed study. The sample size is exploratory. For the primary objective of safety, side effects will be monitored the day of and the day following radiotracer administration. As the PET radiotracer used in this trial is given at a low, imaging dose, serious adverse events are not expected. If a single serious adverse event is identified, then the protocol will be held until reviewed by the IRB. For the secondary objective of dosimetry, dosimetry will be calculated from PET/CT images and radioactive counts in blood samples by an experience medical physicist. For the secondary objective of effectiveness, the number of suspected PSMA-positive malignant lesions will be calculated in both the standard-of-care 18F-Piflufolastat PET/CT and the experimental 61Cu- PSMA PET/CT. Positive lesions will be considered to be the foci greater than local background that are not physiologic/benign by location. The percentage of patients with any suspected PSMApositive malignant lesions will be determined for each radiotracer.