Imaging infections using a special radioactive compound

Phase 1 Biodistribution and Pathophysiology Study of 11C-para-aminobenzoic Acid (11C-PABA)

This study is testing a special radioactive compound to see if it can help doctors better identify infections in people who have confirmed infections or certain diseases.

Quick facts

• Study type: Observational
• Enrollment: 30 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Johns Hopkins University (Academic / other)
• Drugs / interventions: radiation
• Locations: 1 site (Baltimore, Maryland)
• Trial ID: NCT05611905 on ClinicalTrials.gov

What this trial studies

This observational study aims to evaluate the effectiveness of 11C-para-aminobenzoic acid (11C-PABA) in imaging infections through radionuclide PET scans. The study will involve subjects with confirmed infections or inflammatory and oncologic diseases to determine if this imaging technique can differentiate between infectious and non-infectious processes. Additionally, it seeks to provide insights into the specific bacterial class responsible for infections. Participants will undergo PET/CT scans after receiving 11C-PABA and probenecid.

Who should consider this trial

Good fit: Ideal candidates include adults with confirmed infections, inflammatory diseases, or oncologic conditions who are undergoing imaging.

Not a fit: Patients with infections who have received more than the specified duration of antibiotic treatment may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance the accuracy of infection diagnosis and improve treatment strategies for patients.

How similar studies have performed: Previous studies using similar imaging techniques have shown promise in improving infection diagnosis, suggesting potential success for this approach.

Eligibility criteria

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:

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

Where this trial is running

Baltimore, Maryland

• Johns Hopkins Medical Institutions — Baltimore, Maryland, United States (Recruiting)

Study contacts

• Principal investigator: Sanjay K Jain, MD — Johns Hopkins University
• Study coordinator: Sanjay K Jain, MD

Conditions Renal Excretion; Bacterial Infections; Inflammatory Disease; Oncologic Disease; PET/CT; Probenecid; 11C-PABA