64Cu-SAR-bisPSMA for Identification of Participants With Recurrence of Prostate Cancer (COBRA)

Phase 1

Completed

• Conditions: Biochemical Recurrence of Malignant Neoplasm of Prostate
• Interventions: Drug: 64Cu-SAR-bisPSMA

• Registration Number: NCT05249127
• Lead Sponsor: Clarity Pharmaceuticals Ltd

Brief Summary

The aim of this study is to determine the safety and efficacy of 64Cu-SAR-bisPSMA and determine the ability of 64Cu-SAR-bisPSMA Positron emission tomography (PET)/computed tomography (CT) to correctly detect the recurrence of prostate cancer in participants with biochemical recurrence of prostate cancer following definitive therapy.

Detailed Description

Participants with biochemical evidence of recurrence of PC were evaluated with 64CU-SAR-bisPSMA PET/CT (Day 0 and Day 1) and by conventional methodologies up to 180 days later, eg. Histopathology/biopsy, conventional imaging, 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-bisPSMA PET/CT. Three separate independent readers assessed the results of the conventional methodologies.

Study Timeline

• Study First Submitted: 2022-02-02
• Study First Submitted QC: 2022-02-10
• Study First Posted: 2022-02-21
• Study Start: 2022-04-11
• Primary Completion: 2023-08-08
• Study Completion: 2023-08-08
• Status Verified: 2024-08
• Results First Submitted: 2024-08-08
• Results First Submitted QC: 2024-09-05
• Last Update Submitted: 2024-09-05
• Results First Posted: 2024-10-01
• Last Update Posted: 2024-10-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 52

Inclusion Criteria

1. At least 18 years of age.

2. Signed informed consent.

3. Life expectancy ≥ 12 weeks as determined by the Investigator.

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

5. Suspected recurrence of prostate cancer (PC) based on rising Prostate-specific antigen (PSA) after definitive therapy on the basis of:

   1. 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
   2. 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).

6. Negative or equivocal findings for PC on conventional imaging performed as part of standard of care workup within 60 days prior to Day 0.

7. The Eastern Cooperative Oncology performance status 0-2.

8. Adequate recovery from acute toxic effects of any prior therapy.

9. Estimated Glomerular Filtration Rate of 30 mL/min or higher.

10. Adequate liver function.

11. 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

1. Participants who received other investigational agents within 28 days prior to Day 0.
2. Participants administered any high energy (>300 kiloelectronvolts (keV)) gamma-emitting radioisotope within 5 physical half-lives prior to Day 0.
3. 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.
4. Known or expected hypersensitivity to 64Cu-SAR-bisPSMA or any of its components.
5. Any serious medical condition or extenuating circumstance which the investigator feels may interfere with the procedures or evaluations of the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
64Cu-SAR-bisPSMA	64Cu-SAR-bisPSMA	Patients will receive a single administration of 200 megabecquerels (MBq) of 64Cu-SAR-bisPSMA.

Primary Outcome Measures

Name	Time	Method
Safety and Tolerability	up to 7 days post injection	Incidence and severity of Treatment-Emergent Adverse Events (TEAE) and Serious Adverse Events. Adverse Events were assessed by CTCAE version 5.0
Participant-level Correct Detection Rate (CDR)- Day 0	Day 0 (1- 4 hours) post injection	The percentage of TP participants on the Day 0 scan out of all participants with a Day 0 scan.
Participant-level CDR- Day 1	Day 1 (24+/-6 Hours) post injection	The percentage of TP participants on the Day 1 scan out of all participants with a Day 1 scan.
Region-level Positive Predictive Value (PPV)- Day 0	Day 0 (1- 4 hours)	The percentage of TP regions on the Day 0 scan out of all positive regions on the Day 0 scan.
Region-level PPV- Day 1	Day 1 (24 +/- 6 hours)	The percentage of TP regions on the Day 1 scan out of all positive regions on the Day 1 scan.

Secondary Outcome Measures

Name	Time	Method
Biodistribution of 64Cu-SAR-bisPSMA- SUVmean	Day 0 (1 -4 hours) and Day 1 (24 +/- 6 hours) post injection	The mean Standardized Uptake Value (SUVmean) in lesions, visceral soft tissue and bone.
Biodistribution of 64Cu-SAR-bisPSMA- SUVmax	Day 0 (1-4 hours) and Day 1 (24 +/- 6 hours)	SUVmax in lesions, visceral soft tissue and bone
Biodistribution of 64Cu-SAR-bisPSMA- SUVr	Day 0 (1-4 hours) and Day 1 (24 +/- 6 hours)	Lesion to Background ratio. SUVmax of the lesion divided by the SUVmean of gluteus background
Participant-level PPV	Day 0 (1-4 hours) and Day 1 (24 +/- 6 hours)	Percentage of TP participants on the Day 0 or Day 1 scan out of all participants with a positive Day 0 or Day 1 scan.
Participant-level Detection Rate (DR)	Day 0 (1-4 hours) and Day 1 (24 +/- 6 hours)	Percentage of participants with a positive Day 0 or Day 1 scan out of all participants with a Day 0 or Day 1 scan.
Participant-level False Positive Rate (FPR)	Day 0 (1-4 hours) and Day 1 (24 +/- 6 hours)	Percentage of false positive (FP) participants on the Day 0 or Day 1 scan out of all participants with a positive Day 0 or Day 1 scan.
Region-level FPR	Day 0 (1-4 hours) and Day 1 (24 +/-6 hours)	Percentage of FP regions on the Day 0 or Day 1 scan out of all positive regions on the Day 0 or Day 1 scan.
Participant-level Discrepant PET Negativity Rate	Day 0 (1-4 hours) and Day 1 (24 +/-6 hours)	Percentage of participants with contradicting Day 0 and Day 1 results for whom the Reference Standard was positive.
Participant-level True Negative Rate (TNR)	Day 0 (1-4 hours) and Day 1 (24 +/-6 hours)	Percentage of TN participants on the Day 0 or Day 1 scan out of all participants with a negative Day 0 or Day 1 scan.
Region-level TNR	Day 0 (1-4 hours) and Day 1 (24 +/- 6 hours)	Percentage of TN regions on the Day 0 or Day 1 scan out of all negative regions on the Day 0 or Day 1 scan.

Trial Locations

Locations (5)

Tower Urology; 🇺🇸 Los Angeles, California, United States

GU Research Network; 🇺🇸 Omaha, Nebraska, United States

New Mexico Cancer Center; 🇺🇸 Albuquerque, New Mexico, United States

Carolina Urologic Research Center; 🇺🇸 Myrtle Beach, South Carolina, United States

Urology San Antonio; 🇺🇸 San Antonio, Texas, United States