A Phase 1 Trial for Evaluation of the Safety, Pharmacokinetics, and [18F] Radiation Dosimetry of CTT1057

The sponsor has developed a PET imaging agent, CTT1057, labeled with 18F, that is based on a small molecule core and targets an extracellular region of PSMA with high affinity. Although comparable to other inhibitors in terms of affinity for PSMA, this unique class of phosphoramidate agents are the only known irreversible PSMA inhibitors. Due to its irreversible binding to PSMA and rapid uptake by PSMA-expressing prostate cancer cells, accumulation at the cancer target is expected to be rapid, specific and sensitive. Twenty patients will be enrolled in parallel in two cohorts: * (Cohort A) Patients with prostate cancer prior to radical prostatectomy (N = 5). * (Cohort B) Patients with evidence of metastatic castration-resistant prostate cancer (N = 15) Participants receive a single intravenous (IV) dose (370 MBq, or 10 mCi) of CTT1057 in this first-in-human trial. Combined PET/MR imaging (prostate + whole body) will be performed following tracer injection. The 5 patients in the pre-prostatectomy cohort will comprise the dosimetry/pharmacokinetic (PK) cohort to establish organ dosimetry and PK profile. Patients in cohort A will undergo planned radical prostatectomy (plus lymph node dissection) within 12 weeks following CTT1057 PET/MR. Patients in cohort B (metastatic prostate cancer) will have the option for metastatic tumor biopsy following CTT1057 PET imaging. The one-time nominal injected dose will be 370 MBq (10 mCi). Estimated mass dose is 20 µg of CTT1057. Dose will be in a volume of 3 - 5 mL, and will be injected intravenously as a bolus injection. Vital signs, adverse event assessment, and 12 lead ECGs will be performed on day 1 before and after dosing.