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PET Imaging of Cannabinoid CB1 Receptors Using [11C]MePPEP

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ClinicalTrials.gov Identifier: NCT00598390
Recruitment Status : Completed
First Posted : January 21, 2008
Last Update Posted : October 6, 2017
Information provided by (Responsible Party):

Study Description
Brief Summary:
The purpose of this protocol is to measure brain CB1 receptors in the hope to better understand how they work, so that one day we can understand how the CB1 receptors are involved in psychiatric, neurological, and behavioral disorders.

Condition or disease Intervention/treatment Phase
Healthy Drug: [11C]MePPEP Phase 1 Phase 2

Detailed Description:

MePPEP is a ligand that is highly selective for the cannabinoid type 1 (CB1) receptor. This receptor is considered the most common G-coupled protein receptor in the brain (Pacher et al., 2006). The CB1 receptor is the site of action of Delta-9-tetrahydrocannbinol (THC), the active compound in marijuana, and is found primarily on the presynaptic terminals of dopaminergic, glutamatergic, GABAergic neurons (Howlett et al., 2002). The function of the CB1 receptor is not entirely clear; however, it has been implicated in several neurological and psychiatric disorders, and a selective inverse agonist, rimonabant, is currently in use in Europe for the treatment of obesity (Van Gaal et al., 2005). [11C]MePPEP was developed to enhance our understanding of the in vivo characteristics of the CB1 receptor (e.g., receptor density and receptor occupancy with pharmaceuticals).

The purpose of this protocol is to establish an accurate method to measure CB1 receptor levels in brain by performing test/retest brain imaging studies. The results of this overall study are required to apply this PET ligand in various neurological and psychiatric disorders in the future.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 19 participants
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: PET Test/Retest Brain Imaging of Cannabinoid CB1 Receptors Using [11C]MePPEP
Study Start Date : January 8, 2008
Primary Completion Date : January 22, 2013
Study Completion Date : January 22, 2013

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arms and Interventions

Outcome Measures

Primary Outcome Measures :
  1. Reproducibility of novel PET tracer for CB1 in brain imaging.

Secondary Outcome Measures :
  1. Distribution and variance of CB1 receptors in the brain of healthy controls.

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes


All subjects must be healthy and aged 18 65 years, with history/physical exam, ECG, and laboratory tests within one year of the PET scan. The volunteer must sign an informed consent form.


  • Current psychiatric illness, substance abuse including marijuana use, or severe systemic disease based on history and physical exam.
  • Laboratory tests with clinically significant abnormalities or positive urine toxicology screen.
  • Prior participation in other research protocols in the last year such that radiation exposure would exceed the annual limits.
  • Pregnancy and breast feeding.
  • Claustrophobia.
  • Presence of ferromagnetic metal in the body or heart pacemaker.
  • Positive HIV test.
  • Employee of the investigative site or an immediate family member of an employee of the investigative site. Immediate family member is defined as a spouse, parent, child, or sibling, whether biological or legally adopted.
  • Employee of Eli Lilly and Company.
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00598390

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institute of Mental Health (NIMH)
Principal Investigator: Robert B Innis, M.D. National Institute of Mental Health (NIMH)
More Information

Responsible Party: National Institute of Mental Health (NIMH)
ClinicalTrials.gov Identifier: NCT00598390     History of Changes
Other Study ID Numbers: 080048
First Posted: January 21, 2008    Key Record Dates
Last Update Posted: October 6, 2017
Last Verified: January 22, 2013

Keywords provided by National Institutes of Health Clinical Center (CC) ( National Institute of Mental Health (NIMH) ):
CB1 Receptor
Brain Imaging
PET Imaging
Healthy Volunteer