Prostate Specific Membrane Antigen (PSMA) Imaging for Detection of Residual and Metastatic Prostate Cancer
Optimizing PSMA Imaging for Enhanced Detection of Residual and Metastatic Prostate Cancer in Low PSA Recurrence (OPERA) Study
1 other identifier
interventional
20
1 country
1
Brief Summary
This is a randomized, open-label, pilot study assessing the impact of a short course of bicalutamide on PSMA expression in patients with prostate cancer belonging to the intermediate unfavorable or high risk group, who have low levels of PSA. Adult patients with biochemically recurrent prostate cancer (BCR PCa) who have a PSA of less than 1.0 ng/mL and who have undergone complete prostatectomy and/or will be undergoing radiotherapy, in combination with standard of care bicalutamide, will be recruited to this study. Patients will be randomized in a 1:1 ratio into Group A (baseline PSMA PET/CT only with bicalutamide standard of care) or Group B (baseline PSMA PET/CT and an additional PSMA PET/CT after 2 weeks of bicalutamide).
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at below P25 for phase_2 prostate-cancer
Started Jun 2026
Shorter than P25 for phase_2 prostate-cancer
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
May 11, 2026
CompletedFirst Posted
Study publicly available on registry
May 18, 2026
CompletedStudy Start
First participant enrolled
June 30, 2026
ExpectedPrimary Completion
Last participant's last visit for primary outcome
July 14, 2027
Study Completion
Last participant's last visit for all outcomes
September 30, 2027
May 18, 2026
May 1, 2026
1 year
May 11, 2026
May 11, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Group B only: Lesion detection rates between PET1 and PET2.
Differences in lesion detection rates between Group B PET1 and PET2 will be analyzed by McNemar's test. Lesion detection rates will be reported by Group B patients at PET1 and PET2 scans and by the two scan sets (first 5 minutes and at 60 minutes post 18F-rhPSMA-7.3 injection).
Baseline and 14 days after start of bicalutamide treatment (total estimated time 14 days)
Secondary Outcomes (5)
Group A and B: Number of lesions detected on early scan versus delayed scan
At baseline and 14 days after start of bicalutamid treatment (total estimated time is 14 days)
Group A and B: Correlation between PSA response and PROSTest after radiation therapy
Through day 90
Group A and B: Comparison of PSA response in patients who are treated with radiation vs. those treated with radiation
Through day 90
Group B only: Correlation between PSA kinetics and detection rates between PET1 and PET2
Through day 90
Group B only: Correlation between PROSTest results and detection rates of PET1 and PET2
14 days after start of bicalutamide treatment (total estimated time 14 days)
Study Arms (2)
Group A: Baseline PSMA PET/CT only with standard of care bicalutamide
ACTIVE COMPARATORPatients will undergo baseline PSMA PET/CT (PET1) with 18F-rhPSMA-7.3 (F-18 flotufolastat, Posluma). After the 18F-rhPSMA-7.3 injection, patients will undergo research imaging consisting of 5 minutes of PET imaging, followed by routine imaging at 60 minutes after 18F-rhPSMA-7.3 injection. Patients will have blood collected for PROSTest and PSA within 1 day of completion of PET1. Following PET1, patients will initiate standard of care bicalutamide for a minimum of 14 days, with the first dose taken the day after PET1. Patients will undergo a 90 day follow-up visit (relative to PET1) for collection of blood for PROSTest and PSA.
Group B: PSMA PET/CT after 2 weeks of standard of care bicalutamide
EXPERIMENTALPatients will undergo baseline PSMA PET/CT (PET1) with 18F-rhPSMA-7.3 (F-18 flotufolastat, Posluma). After the 18F-rhPSMA-7.3 injection, patients will undergo research imaging consisting of 5 minutes of PET imaging, followed by routine imaging at 60 minutes after 18F-rhPSMA-7.3 injection. Patients will have blood collected for PROSTest and PSA within 1 day of completion of PET1. Following PET1, patients will initiate standard of care bicalutamide for a minimum of 14 days, with the first dose taken the day after PET1 and will undergo a research PSMA PET/CT (PET2) on Day 14 (±3 days). The research PSMA PET/CT (PET2) will follow the same imaging procedures as the baseline PET. Patients will undergo a 90 day follow-up visit (relative to PET1) for collection of blood for PROSTest and PSA.
Interventions
Bicalutamide is a non-steroidal androgen receptor inhibitor administered as a once a day pill taken orally. This is given as standard of care.
Patients will undergo prostate-specific membrane antigen Positron Emission Tomography-Computed Tomography (PSMA PET-CT) imaging. Each PSMA PET-CT session will consist of 5 minutes of dynamic imaging conducted via the Biograph Vision Quadra PET-CT, a whole-body PET-CT scanner.
Radioactive diagnostic agent for intravenous use.
PROSTest is a novel, blood-based qPCR assay that assesses gene expression to diagnose PCa and predict patient outcomes to different treatments.
Eligibility Criteria
You may qualify if:
- Histologically or cytologically confirmed biochemically recurrent prostate cancer, with original diagnosis no more than 2 years from date of consent.
- Intermediate unfavorable or high-risk prostate cancer.
- All patients under consideration for radiation therapy, either at the time of first recurrence or in salvage radiation therapy will be included.
- Patients who have started bicalutamide up to a maximum of 3 days prior to randomization will be allowed to be on protocol. Otherwise, a washout period of at least 42 days will be required.
- Biological males, at least 18 years of age.
- Prostate specific antigen (PSA) \< 1.0 ng/mL.
- Agreement to adhere to Lifestyle Considerations throughout study duration
- Ability to understand and willingness to sign an IRB approved written informed consent document.
You may not qualify if:
- Patients currently on androgen deprivation therapy (ADTs).
- Currently receiving any other investigational agents.
- A history of allergic reactions attributed to compounds of similar chemical or biologic composition to POSLUMA, furosemide, bicalutamide, or other agents used in the study.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Washington University School of Medicine
St Louis, Missouri, 63110, United States
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Vikas Prasad, MD, PhD
Washington University School of Medicine
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- DIAGNOSTIC
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
May 11, 2026
First Posted
May 18, 2026
Study Start (Estimated)
June 30, 2026
Primary Completion (Estimated)
July 14, 2027
Study Completion (Estimated)
September 30, 2027
Last Updated
May 18, 2026
Record last verified: 2026-05
Data Sharing
- IPD Sharing
- Will not share