18F-FTHA IMAGING OF THE INTESTINAL AND CENTRAL LYMPHATIC SYSTEM (FTHA)

INVESTIGATION OF A POSITRON-EMITTING LONG-CHAIN FATTY ACID (18F-FTHA), FOR IMAGING OF THE INTESTINAL AND CENTRAL LYMPHATIC SYSTEM

The project will be performed over a period of approximately two years. In the first year the [18F]FTHA tracer will be developed, optimized, and tested on normal volunteers. During the second year, the tracer will be investigated on patients with suspected obstruction of the thoracic duct (TD).

Study Overview

• Status: Recruiting
• Conditions: Lymphatic Obstruction
• Intervention / Treatment: Diagnostic test: [18F]FTHA PET/CT scan

Detailed Description

Initially up to 10 healthy adult volunteers will be recruited for the study. All subjects will be instructed to fast overnight before the scan visit. On the study day, subjects will be fasting, and then asked to consume an Ensure drink after [18F]FTHA administration and before imaging begins. Tracer administration vial oral capsules and PET/CT imaging: All subjects will receive approximately 1.0 -1.5 mCi (approximately 37-55 MBq) of [18F]FTHA administered orally followed by dynamic imaging for up to 4 hours, with breaks between scan sessions (Figure 4) on a whole-body PET/CT system.

An additional 15 patients with clinically suspected obstruction of the TD-venous junction with symptoms that may include chronic abdominal pain, edema, protein losing enteropathy and/or ascites, will be studied using the same administration and imaging procedures.

Participants with disease may undergo a standard of care clinical surgical bypass procedure and be asked to return post-surgery for a follow up PET/CT imaging session.

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Erin K Schubert, BA; Phone Number: 2155736569; Email: erin.schubert@pennmedicine.upenn.edu
• Study Contact Backup: Name: Mary Hansbury, BS; Phone Number: 215-746-8192; Email: mary.hansbury@pennmedicine.upenn.edu

Study Locations

• United States
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Recruiting
      • University of Pennsylvania Hospital
      • Contact: Erin Schubert; Phone Number: 215-573-6569; Email: erinschu@pennmedicine.upenn.edu
      • Principal Investigator: Paco Bravo, MD
      • Sub-Investigator: Maxim Itkin, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Inclusion Criteria (Healthy Volunteer Cohort)

1. Male and female participants will be ≥ 18 years of age.
2. "Healthy Volunteer" is defined for the purposes of this study as a volunteer who is in good general health in the opinion of an investigator (some well controlled chronic medical conditions may be allowed at the discretion of an investigator if they do not believe they will interfere with the collection of imaging data, specific excluded medical conditions are listed under exclusion criteria).
3. Informed of the investigational nature of this study and able to provide written informed consent and participate in this study in accordance with institutional and federal guidelines prior to study-specific procedures.

Inclusion (Patient with suspected TD-venous junction obstruction cohort)

1. Male and female participants will be ≥ 18 years of age
2. Informed of the investigational nature of this study and able to provide written informed consent and participate in this study in accordance with institutional and federal guidelines prior to study-specific procedures.
3. Patient with chronic abdominal pain, ascites protein losing enteropathy, as well edema, with clinically suspected obstruction of the TD-venous junction and who are candidates for TD-venous junction plasty and or TD-Venous bypass

Exclusion Criteria:

Exclusion Criteria that apply to Healthy Volunteers only

1. Currently taking medication for cardiac disease, hypertension, hyperlipidemia, diabetes mellitus, heart failure, coronary artery disease, and/or history of cardiac surgery per medical record review and/or self-report
2. Known history of liver or kidney disease per medical record review and/or self-report

Exclusion Criteria that applies to Healthy Volunteers and Patients:

1. Women who are pregnant or breast feeding will not be eligible for this study; a urine pregnancy test will be performed in women of child-bearing potential on the day of each of the PET/CT scans.
2. Subjects who report claustrophobia or Inability to tolerate imaging procedures in the opinion of an investigator or treating physician
3. Self-reported difficulty with swallowing pills or allergy to components of Ensure Plus
4. Patients with a history of medical illness or disorder that in the opinion of an investigator and/or study physician could compromise patient safety or interfere with the collection of imaging data, or ability to complete the study and procedures, will be excluded.

Participant may not be involved in any other research studies involving ionizing radiation conducted within 1 year of their participation of this study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Healthy Volunteer; Healthy volunteers will undergo a single injection of [18F]-FTHA (a long-chain fatty acid positron emitting radiotracer) followed by up to 4 PET/CT scans.	Diagnostic test: [18F]FTHA PET/CT scan; Positron Emission Tomography/Computed Tomography (PET/CT) scans
Experimental: TD-Venous Obstruction patients; Patients with known or suspected obstruction of the thoracic duct (TD)-venous junction will undergo a single injection of [18F]-FTHA (a long-chain fatty acid positron emitting radiotracer) followed by up to 4 PET/CT scans. If the patient undergoes a clinical surgical procedure then they will be asked to undergo a second [18F]FTHA PET/Ct scan following the same procedure as the baseline scan.	Diagnostic test: [18F]FTHA PET/CT scan; Positron Emission Tomography/Computed Tomography (PET/CT) scans

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
FTHA transit time	To determine the normal [18F-]FTHA transit times through the intestinal lymphatic system, and TD among healthy human subjects imaged on a whole body PET/CT scanner.	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dosimetry	Calculation of radiation dosimetry from FTHA for whole body and individual organs will be completed.	4 weeks

Collaborators and Investigators

• Sponsor: University of Pennsylvania

Study record dates

Study Major Dates

• Study Start (Actual): October 10, 2025
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2029

Study Registration Dates

• First Submitted: June 8, 2026
• First Submitted That Met QC Criteria: June 8, 2026
• First Posted (Actual): June 12, 2026

Study Record Updates

• Last Update Posted (Actual): June 12, 2026
• Last Update Submitted That Met QC Criteria: June 8, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: thoracic duct
• Other Study ID Numbers: 857341

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

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