Inclusion Criteria:

1. At least 18 years of age.

2. Signed informed consent.

3. Life expectancy ≥ 6 months as determined by the Investigator.

4. Histologically confirmed adenocarcinoma of prostate per original diagnosis and completed subsequent definitive therapy.

5. Participant potentially eligible for salvage therapy with curative intent (i.e. aligns with the definition of loco-regional therapy as described in protocol Section 7.2).

6. PSA level after definitive therapy:

   1. Post-radical prostatectomy: Detectable or rising PSA that is ≥ 0.2 ng/mL with a confirmatory PSA ≥ 0.2 ng/mL (per AUA recommendation) or
   2. Post-radiation therapy, cryotherapy, or brachytherapy: Increase in PSA level that is elevated by ≥ 2 ng/mL above the nadir (per ASTRO-Phoenix consensus definition).

7. Participant willing to undergo biopsy of a 64Cu-SAR-bisPSMA PET-positive lesion for histological confirmation of PC, where this is safe and feasible.

8. An Eastern Cooperative Oncology performance status of 0-2.

Exclusion Criteria:

1. Participants who received investigational agent within 5 biological half-lives prior to Day 1.
2. Participants administered any high energy (>300 KeV) gamma-emitting radioisotope within 5 physical half-lives prior to Day 1.
3. Participants with known predominant small cell or neuroendocrine PC.
4. Previous systemic therapy for PC (with the exception of neoadjuvant and adjuvant systemic therapy as part of the definitive therapy and/or salvage therapy with radiation).
5. Ongoing treatment or treatment within 6 months of Day 1 with any systemic therapy (e.g. any investigational therapy, androgen-deprivation therapy, antiandrogen, gonadotropin-releasing hormone, luteinizing hormone-releasing hormone agonist or antagonist, chemotherapy, immunotherapy or radiotherapy) for PC.
6. Participants for whom there is an intent to initiate a prohibited medication(s)/treatment(s) (refer to Section 7.3) during the course of the participant's involvement in the study.
7. Known or expected hypersensitivity to 64Cu-SAR-bisPSMA or any of its components.
8. Any serious medical condition or extenuating circumstance (including receiving the investigational product or not capable of having a PET scan) which the investigator feels may interfere with the procedures or evaluations of the study.