Full Text View
Tabular View
No Study Results Posted
Related Studies
PET Whole Body Imaging Using a Peripheral Benzodiazepine Receptor Ligand [C-11]PBR28
This study is currently recruiting participants.
Verified by National Institutes of Health Clinical Center (CC), September 2008
First Received: December 2, 2006   Last Updated: June 9, 2009   History of Changes
Sponsored by: National Institute of Mental Health (NIMH)
Information provided by: National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier: NCT00407693
  Purpose

In this study we will examine where the radioactive tracer [11C]PBR28 is distributed in the body of healthy volunteers to calculate the radiation exposure to organs of the body. We will also test if [11C]PBR28 binds to your blood cells and compare with the binding in PET images.


Condition Intervention
Healthy
Drug: [C-11]PRB28

Study Type: Interventional
Study Design: Diagnostic, Non-Randomized, Open Label, Uncontrolled, Single Group Assignment, Pharmacokinetics Study
Official Title: PET Whole Body Imaging Using a Peripheral Benzodiazepine Receptor Ligand [C-11]PBR28

Further study details as provided by National Institutes of Health Clinical Center (CC):

Primary Outcome Measures:
  • Biodistribution of [C-11]PBR28

Estimated Enrollment: 40
Study Start Date: November 2006
Estimated Study Completion Date: September 2008
Estimated Primary Completion Date: September 2008 (Final data collection date for primary outcome measure)
Intervention Details:
    Drug: [C-11]PRB28
    N/A
Detailed Description:

The peripheral benzodiazepine receptor (PBR) is distinct from central benzodiazepine receptors associated with GABA(A) receptors. Although PBR was initially identified in peripheral organs such as kidneys, endocrine glands and lungs, later studies identified PBR in the central nervous system. In normal conditions, PBR is expressed in low levels in some neurons and glial cells. PBR can be a clinically useful marker to detect neuroinflammation because activated microglial cells in inflammatory areas express much greater levels of PBR than in microglial cells in resting conditions.

PBR has been imaged with positron emission tomography (PET) using [11C]1-(2-chlorophenyl-N-methylpropyl)-3-isoquinoline carboxamide (PK11195). However, this classical ligand provides only low levels of specific signals and is not sensitive to detect changes that occurred in vivo. Recently we developed a new ligand, N-acetyl-N-(2-[11C]methoxybenzyl)-2-phenoxy-5-pyridinamine ([11C]PBR28), which showed much greater specific signals than [11C]PK11195 in non-human primates. Therefore, [11C]PBR28 is a promising PET ligand. However, radiation absorbed doses have not been estimated from human whole body imaging.

The initial purpose of this protocol is to estimate radiation absorbed doses of [11C]PBR28 by performing whole body imaging studies on ten healthy human subjects. The results of this overall study are required to apply this PET ligand in various neurological and psychiatric disorders in the future. The secondary purpose is to compare in vivo and in vitro binding of PBR28 by performing whole body PET scans and in vitro binding assays using blood cells for the following reasons. Under the current and other protocols using PBR28, we found that approximately 15 percent (3/20) of subjects did not have in vivo binding of PBR28. We also performed an in vitro binding assay of PBR28 using lymphocytes of one of the in vivo non-binders and found the presence of specific binding in vitro. We plan to find a percentage of non-binders and study if there is really discrepancies between in vivo and in vitro binding.

  Eligibility

Ages Eligible for Study:   18 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria
  • INCLUSION CRITERIA:

All subjects must be healthy and aged 18-65 years.

EXCLUSION CRITERIA:

The exclusion criteria are shown below:

  • Current psychiatric disease, substance abuse or severe systemic disease based on history and physical exam.
  • Laboratory tests with clinically significant abnormalities.
  • Prior participation in other research protocols or clinical care in the last year such that radiation exposure including that from this protocol would exceed the guidelines set by the Radiation Safety Committee (RSC).
  • Pregnancy and breast feeding.
  • Positive HIV test.
  • Cannot lie flat for 2 - 3 h.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00407693

Contacts
Contact: Patient Recruitment and Public Liaison Office (800) 411-1222 prpl@mail.cc.nih.gov
Contact: TTY 1-866-411-1010

Locations
United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike Recruiting
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
  More Information

Additional Information:
Publications:
Study ID Numbers: 070035, 07-M-0035
Study First Received: December 2, 2006
Last Updated: June 9, 2009
ClinicalTrials.gov Identifier: NCT00407693     History of Changes
Health Authority: United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Dosimetry
Effective Dose
Radiation-Absorbed Dose

Study placed in the following topic categories:
Healthy

ClinicalTrials.gov processed this record on July 02, 2009