NCT01699828

Exploring Occupancy of Dopamine D3 Receptor by Buspirone in Humans Using PET

• Status: Completed
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 6 (actual)
• Sponsor: Centre for Addiction and Mental Health · Academic / Other
• Sex: All
• Age: 19 Years – 65 Years
• Healthy volunteers: Accepted

Summary

The objective of the present study is to use positron emission tomography brain imaging to investigate D3 occupancy of buspirone, an FDA-approved anxiolytic which acts as a serotonin partial agonist but has recently been identified as a D3 antagonist. It is hypothesized that clinically relevant doses of buspirone will occupy the D3 receptor.

Detailed description

Buspirone is used for anxiety disorder treatment, a therapeutic effect that has been thought to be mediated through its partial agonist properties at the serotonin receptor. However, since one PET study in humans has shown low occupancy of the serotonin by buspirone in clinical doses and since the DRD3 has been recently implicated in anxiety, some therapeutic effects of buspirone may be mediated through the DRD3. In human clinical studies, promising effects of buspirone have been reported for treatment of substance dependence, including tobacco, marijuana, and opiates, and clinical studies in cocaine dependent subjects are underway. However, it is unclear if buspirone is producing those effects through the DRD3 and no human study has incorporated a PET imaging component to investigate this question; it remains unclear whether buspirone significantly occupies the DRD3 at therapeutic doses in humans.

Conditions

• Smoking Cessation
• Tobacco Use Cessation

Interventions

Type	Name	Description
DRUG	Buspirone	The buspirone will be given once as a tablet and encapsulated for blinding.
DRUG	Placebo	Placebo will be lactose and encapsulated for blinding. A single capsule will be given.

Timeline

• Start date: 2012-10-01
• Primary completion: 2014-06-01
• Completion: 2014-06-01
• First posted: 2012-10-04
• Last updated: 2014-06-04

Locations

1 site across 1 country: Canada