64Cu-SAR-BBN for Identification of Participants With Recurrence of Prostate Cancer (SABRE)

Participants with biochemical evidence of recurrence of prostate cancer (PC) were evaluated with 64Cu-SAR-BBN PET/CT (Day 0 and Day 1) and by conventional methodologies up to 180 days later (e.g., histopathology/biopsy, conventional imaging, prostate specific antigen [PSA] reduction post focal salvage therapy or radiotherapy with no concomitant androgen deprivation therapy). Three independent, central readers blinded to the participant number, the time of the PET/CT scan, and the results of the conventional methodologies, assessed the 64Cu-SAR-BBN PET/CT. Three separate independent readers assessed the results of the conventional methodologies.

Inclusion criteria

• At least 18 years of age.
• Signed informed consent.
• Life expectancy ≥ 12 weeks as determined by the Investigator.
• Histologically confirmed adenocarcinoma of prostate per original diagnosis and completed subsequent definitive therapy.
• Suspected recurrence of PC based on rising PSA after definitive therapy on the basis of:

• Post-radical prostatectomy: Detectable or rising PSA that is ≥ 0.2 ng/mL with a confirmatory PSA ≥ 0.2 ng/mL (per American Urological Association recommendation) or
• Post-radiation therapy, cryotherapy, or brachytherapy: Increase in PSA level that is elevated by ≥ 2 ng/mL above the nadir (per American Society for Therapeutic Radiology and Oncology-Phoenix consensus definition).
• Negative or equivocal findings for PC on (1) approved PSMA PET and (2) anatomical imaging (CT and/or magnetic resonance imaging) and (3) if available, any other conventional imaging performed as part of routine standard of care imaging workup within 60 days prior to Day 0.
• The Eastern Cooperative Oncology performance status 0-2.
• Adequate recovery from acute toxic effects of any prior therapy.
• Estimated Glomerular Filtration Rate of 30 mL/min or higher.
• Adequate liver function.
• For participants who have partners of childbearing potential: Partner and/or participant must use a method of birth control with adequate barrier protection.

Exclusion criteria

• Participants who received other investigational agents within 28 days prior to Day 0.
• Participants administered any high energy (>300 kiloelectronvolts (keV)) gamma-emitting radioisotope within 5 physical half-lives prior to Day 0.
• Ongoing treatment or treatment within 90 days of Day 0 with any systemic therapy (e.g. androgen-deprivation therapy, antiandrogen, gonadotropin-releasing hormone, luteinizing hormone-releasing hormone agonist or antagonist) for PC.
• Participants who are known to require prohibited treatment (e.g., initiation of androgen-deprivation therapy due to rapidly rising PSA) before the 64Cu-SAR-BBN PET/CT results can be verified via histopathology or follow-up imaging.
• Known or expected hypersensitivity to 64Cu-SAR-BBN or any of its components.
• Any serious medical condition or extenuating circumstance which the investigator feels may interfere with the procedures or evaluations of the study.