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CompletedNCT05611905Updated Dec 12, 2025

Biodistribution and Pathophysiology Study of 11C-para-aminobenzoic Acid

An observational study in Renal Excretion, Bacterial Infections and Inflammatory Disease, sponsored by Johns Hopkins University. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-12.

Sponsored by Johns Hopkins University · Observational

Study type
Observational
Model
Other
Time perspective
Prospective
Enrollment
13
Ages
18 Years and older
Sex
All
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Study summary

The investigators will perform radionuclide PET scans in subjects with infectious diseases to assess whether radio-labeled PABA (11C-PABA) is effective for infection imaging.

Tomographic imaging can be used to evaluate disease processes deep within the body, noninvasively and relatively rapidly. The goal is to see if this imaging technique can help differentiate infections from non-infectious processes and also provide information on the causative bacterial class.

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Conditions studied

  • Renal Excretion
  • Bacterial Infections
  • Inflammatory Disease
  • Oncologic Disease

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Keywords

  • PET/CT
  • Probenecid
  • 11C-PABA
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In context

Bacterial Infections

658 studies on the registry are indexed under Bacterial Infections; 100 are open to participants now.

This study's enrollment of 13 is below the median of 200 across 229 observational studies indexed under Bacterial Infections.

Browse Bacterial Infections studies →

Lead sponsor

Johns Hopkins University is the lead sponsor of 1,783 studies on the registry; 313 are open to participants now.

Of its 203 completed or terminated interventional studies of FDA-regulated products, 140 (69%) have results posted.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Sampling method
Non-probability sample

Study population

Patients with bacterial infections or non-infectious processes such as inflammatory / oncologic diseases will be enrolled. Males and female members of all races and ethnic groups are eligible for this trial and encouraged to participate.

Inclusion criteria

  1. Male or female ≥18 years of age at the time of consent and imaging.
  2. Healthy subjects OR those with confirmed (microbiologically, molecular or serological testing) diagnosis of infection at any body site OR clinical and imaging evidence of suspected infection in any body site with confirmation (microbiologically, molecular or serological testing) anticipated within 72 hours of imaging.

    OR subjects with confirmed inflammatory (rheumatoid arthritis, idiopathic pulmonary fibrosis, etc) or oncologic (e.g. localized or metastatic tumors) disease and clinically determined not to have infection.

  3. For subjects with infections:

    Non mycobacterium tuberculosis infections: received no more than 7 days of effective antibiotic treatment, as judged by the attending and/or principal investigator.

    OR Mycobacterium tuberculosis or mycobacteroides infections: received no more than 4 weeks of effective treatment. Infection confirmed by positive culture or molecular testing.

  4. For inpatients, determined by the attending of record to be stable to participate in the study (will be documented in the research records).
  5. Subject is judged by the investigator to have the initiative and means to be compliant with the protocol.
  6. Subjects or their legal representatives must have the ability to read, understand and provide written informed consent for the initiation of any study related procedures. Adults lacking capacity will not be enrolled in this study.

Exclusion criteria

Exclusion criteria:

Within 28 or fewer days prior to imaging, a complete blood count with differential, blood comprehensive metabolic panel will be performed. Subjects will be excluded from enrollment if any of the following apply:

  1. Reported pregnancy or pregnancy as determined by positive or indeterminate serum human chorionic gonadotrophin (hCG) at screening and positive urine hCG prior to radiopharmaceutical dosing.
  2. Lactating females.
  3. Inadequate venous access.
  4. Screening clinical laboratory values must be within normal limits or judged not clinically significant by the principal investigator.
  5. Administered a radioisotope within 5 physical half-lives prior to study enrollment.
  6. Subject has been treated with an investigational drug / biologic / therapeutic device within 30 days prior to study radiotracer administration.
  7. Determined to have prior (external) radiation exposure which will exceed RDRC annual radiation exposure limit of 5 rems.
  8. For patients undergoing renal imaging they will be excluded if any of the following conditions exist:

    • Hypertension
    • Diabetes mellitus type I or II
    • Body mass index less than 18.5 kg/m2 or higher than 30 kg/m2
    • Family history of renal disease
    • Urinary tract infection in the prior 6 months
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Study design

Observational model
Other
Time perspective
Prospective
Enrollment
13 participants (actual)
Patient registry
No

Groups and cohorts

  • 11C-para-aminobenzoic acid PET/CT

    Combination Product: 11C-para-aminobenzoic acid PET/CT · Drug: Probenecid

Interventions

  • Combination product11C-para-aminobenzoic acid PET/CT

    A bolus of 20 mCi of 11C-PABA followed by PET/CT

  • DrugProbenecid

    Oral dose of 500 mg (tablet) 2 hours before IV dose of 11C-PABA will be administered.

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What researchers measure

Primary outcomes

  1. Pathophysiology of 11C-PABA in diseased subjects

    Reconstruction of the PET data will be performed by means of iterative reconstruction (IR) by the ordered subset-expectation-maximization (OSEM) method with CT attenuation correction.

    Time frame: Up to 3 hours

  2. Biodistribution of 11C-PABA in diseased subjects

    Reconstruction of the PET data will be performed by means of iterative reconstruction (IR) by the ordered subset-expectation-maximization (OSEM) method with CT attenuation correction.

    Time frame: Up to 3 hours

07

Study locations

1 site
  • Johns Hopkins Medical Institutions
    Baltimore, Maryland 21218, United States
08

References and documents

Publications

  • Masias-Leon Y, Ruiz-Gonzalez CE, Nino-Meza OJ, Singh M, Sarhan MO, Chen X, Flavahan K, Kronenberg A, Tucker EW, Freundlich JS, Lodge MA, Carroll LS, Parrish N, Lechtzin N, Jain SK. Dynamic 11C-Para-Aminobenzoic Acid Positron Emission Tomography/Computed Tomography for Visualizing Pulmonary Mycobacteroides abscessus Infections. Am J Respir Crit Care Med. 2025 Jul;211(7):1253-1263. doi: 10.1164/rccm.202409-1792OC. PubMed 40153540 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 12, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT05611905
Lead sponsor
Johns Hopkins University
Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
Responsible party
Sponsor
First posted
Nov 10, 2022
Start date
Dec 22, 2023
Primary completion
Nov 8, 2025
Completion
Nov 8, 2025
Last update
Dec 12, 2025

Study contacts

Sanjay K Jain, MD
principal investigator · Johns Hopkins University

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.

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