Comparison of 18F-rhPSMA-7.3 PET/CT With and Without Furosemide in Biochemical Recurrence of Prostate Cancer

Strategy to Reduce Bladder Activity With RhPSMA 7.3: Comparison of 18F-RhPSMA 7.3 PET/CT With and Without Furosemide in Biochemical Recurrence of Prostate Cancer

This phase II trial evaluates Fluorine-18 radiohybrid prostate-specific membrane antigen (18F- rhPSMA)-7.3 positron emission tomography (PET)/computed tomography (CT) scans with and without furosemide for the reduction of bladder activity in patients with prostate cancer that has come back (recurrent) based on elevated levels of prostate-specific antigen (PSA) in the blood (biochemical) after prostate surgery (prostatectomy). Furosemide is a diuretic substance that increases the urine flow into the bladder, thereby decreasing the level of radioactivity within the bladder, which may help to see any abnormal areas that could be masked by the radioactivity within the bladder. PET is an established imaging technique that utilizes small amounts of radioactivity attached to very minimal amounts of tracer, in the case of this research, rhPSMA ligand. CT utilizes x-rays that traverse body from the outside. CT images provide an exact outline of organs and potential inflammatory tissue where it occurs in patient's body. Adding furosemide to 18F-rhPSMA 7.3 PET/CT scans may help to better detect and treat patients with biochemically recurrent prostate cancer.

Study Overview

• Status: Active, not recruiting
• Conditions: Prostate Adenocarcinoma; Recurrent Prostate Carcinoma
• Intervention / Treatment: Procedure: Computed Tomography; Procedure: Positron Emission Tomography; Drug: Furosemide; Other: F18-rhPSMA-7.3

Detailed Description

PRIMARY OBJECTIVE:

I. To determine if administering 20 mg furosemide intravenously (IV) at the time of radiotracer injection significantly reduces bladder activity compared with the same patient scanned without furosemide as internal control.

SECONDARY OBJECTIVES:

I. To compare detection rates of recurrent disease in blinded interpretations between the furosemide and non-furosemide 18FrhPSMA-7.3 PET/CT scans, with patients serving as their own internal controls.

II. To compare reader confidence in identifying prostate bed and other recurrent lesions on a 18F-rhPSMA-7.3 PET/CT with furosemide compared with 18F-rhPSMA-7.3 PET/CT without furosemide.

OUTLINE:

Patients receive 18F-rhPSMA 7.3 tracer IV and then undergo PET-CT scans with and without furosemide IV on study.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Georgia
    • Atlanta, Georgia, United States, 30308
      • Emory University Hospital Midtown
    • Atlanta, Georgia, United States, 30322
      • Emory University Hospital/Winship Cancer Institute
    • Atlanta, Georgia, United States, 30342
      • Emory Saint Joseph's Hospital
    • Johns Creek, Georgia, United States, 30097
      • Emory Johns Creek Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adenocarcinoma of the prostate, post-prostatectomy
• Biochemical recurrence of prostate cancer following radical prostatectomy (RP) with or without adjuvant or salvage therapy: PSA >= 0.2 ng/mL followed by a subsequent confirmatory PSA value >= 0.2 ng/mL
• Age over 18
• Ability to provide written informed consent
• Patients with standard of care creatinine =< 1.3 mg/dL performed within 90 days prior to enrollment

Exclusion Criteria:

- Inability to undergo 18F-rhPSMA PET-CT, contraindications to furosemide or urinary incontinence

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Treatment (furosemide, F-18 rhPSMA-7.3, PET-CT); Patients receive F-18 rhPSMA 7.3 tracer IV and then undergo PET-CT scans with and without furosemide IV on study.

Procedure: Computed Tomography; Undergo PET/CT scan; Other Names: CAT, CAT Scan, CAT scan, CAT Scan,Computed Axial Tomography,Computed Tomography, Computerized Axial Tomography; Procedure: Positron Emission Tomography; Undergo PET/CT scan; Other Names: Medical Imaging,Positron Emission Tomography, PET, PET SCAN; Drug: Furosemide; Given IV; Other Names: 54-31-9, FRS, Furosemide, FUROSEMIDE, Lasix, Lasix, LB 502, LB-502, LB-502, SK-Furosemide; Other: F18-rhPSMA-7.3; Given IV; Other Names: (18F)-rhPSMA-7.3,18F-rhPSMA-7.3,18FrhPSMA-7.3,2305081-64-3,F-18-rhPSMA-7.3,FLOTUFOLASTAT F-18, Fluorine F18 radiohybrid PSMA-7.3, Fluorine F18 rhPSMA-7.3, Fluorine-18 rhPSMA-7.3, rhPSMA-7.3(18F)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Bladder Activity as Measured by Bladder Standardized Uptake Value (SUV) Mean	Change in bladder SUV mean will be assessed using a paired t-test, or using a non-parametric equivalent such as a Wilcoxon signed rank test. Descriptively, change in bladder SUV mean will be reported for those administered 20 mg furosemide intravenously (IV) at the time of radiotracer injection first (group A), and those administered 20mg furosemide IV at the time of radiotracer injection second (group B).	Up to 2 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Bladder and Renal Activity (Kidney SUV)	Kidney SUV - Change in bladder and renal activity will be assessed using paired t-tests, or using non-parametric equivalents such as a Wilcoxon signed rank tests. Descriptively, bladder and renal activity will be reported for those administered 20 mg furosemide IV at the time of radiotracer injection first (group A), and those administered 20 mg furosemide IV at the time of radiotracer injection second (group B).	Up to 2 weeks
Change in Bladder and Renal Activity (Bladder Volume, ML)	(Bladder Volume, ML) - Change in bladder and renal activity will be assessed using paired t-tests, or using non-parametric equivalents such as a Wilcoxon signed rank tests. Descriptively, bladder and renal activity will be reported for those administered 20 mg furosemide IV at the time of radiotracer injection first (group A), and those administered 20 mg furosemide IV at the time of radiotracer injection second (group B).	Up to 2 weeks
Recurrent Disease Rate	Defined as presence of unequivocal soft tissue radiotracer uptake that is characteristic of malignancy in the prostate bed and/or surrounding soft tissues and within pelvic lymph nodes. Recurrent disease rates will be compared (furosemide versus non-furosemide flotufolastat F-18 radiohybrid prostate-specific membrane antigen (18F-rhPSMA)-7.3 positron emission tomography (PET) scans using McNemar's tests. Rates will be reported, along with 95% exact confidence intervals using the Clopper-Pearson method. Descriptively, recurrent disease rate will be reported for those administered 20 mg furosemide IV at the time of radiotracer injection first (group A), and those administered 20 mg furosemide IV at the time of radiotracer injection second (group B).	Up to 2 weeks
Reader Confidence Score	The readers' confidence in identifying prostate bed, pelvic and retroperitoneal nodal disease and other recurrence on 18F-rhPSMA-7.3 PET/computed tomography (CT) with furosemide compared with the 18F-rhPSMA-7.3 PET/CT without furosemide will be scored using a 5-point Likert scale ( 1 - Definitely benign, 2- probably benign, 3 - equivocal, 4 - probably malignant, 5 - definitely malignant). This analysis will be descriptive, with summary statistics reported with and without furosemide. Variables will be summarized using frequencies and percentages. In our analysis, 1,2 (no) will be considered benign while 3,4,5 malignant (yes). A high Likert score indicates that the reader is confident that the finding on the imaging is cancer (worse outcome), while a low score indicates no cancer (better outcome). All tests will be two-sided with an alpha level of 0.05, unless otherwise noted. Statistical analysis will be conducted using SAS 9.4.	1 Month

Collaborators and Investigators

• Sponsor: Emory University
• Collaborators: National Cancer Institute (NCI); Blue Earth Diagnostics
• Investigators: Principal Investigator: Charles V. Marcus, MBBS, Emory University Hospital/Winship Cancer Institute

Study record dates

Study Major Dates

• Study Start (Actual): April 27, 2023
• Primary Completion (Actual): March 15, 2024
• Study Completion (Estimated): July 1, 2028

Study Registration Dates

• First Submitted: February 17, 2023
• First Submitted That Met QC Criteria: March 9, 2023
• First Posted (Actual): March 22, 2023

Study Record Updates

• Last Update Posted (Estimated): October 27, 2025
• Last Update Submitted That Met QC Criteria: October 10, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Prostatic Diseases; Male Urogenital Diseases; Prostatic Neoplasms; Sulfur Compounds; Organic Chemicals; Investigative Techniques; Physical Phenomena; Amides; Aniline Compounds; Amines; Chemistry Techniques, Analytical; Spectrum Analysis; Electromagnetic Phenomena; Magnetic Phenomena; Sulfonamides; Sulfanilamides; Sulfones; Electromagnetic Radiation; Radiation; Radiation, Ionizing; Furosemide; Magnetic Resonance Spectroscopy; X-Rays; 2-phenyl-6-(2'-(4'-(ethoxycarbonyl)thiazolyl))thiazolo(3,2-b)(1,2,4)triazole
• Other Study ID Numbers: STUDY00004720 (Other Identifier: Emory University Hospital/Winship Cancer Institute); P30CA138292 (U.S. NIH Grant/Contract); RAD5689-22-BED-IIT-439 (Other Identifier: Emory University Hospital/Winship Cancer Institute); NCI-2023-01322 (Registry Identifier: CTRP (Clinical Trial Reporting Program))

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No