A PET Study in Healthy Volunteers

Depressive Disorder Clinical Trial

Official title: A Positron Emission Tomography Study in Healthy Male Subjects to Examine the Test-retest Reliability of the D2/3 Agonist Radiotracer [11C]PHNO

Status Completed

Clinical Trial Summary

This will be an open label, non-randomised [11C]PHNO PET study using healthy male volunteers. Each volunteer will undergo 4 [11C]PHNO PET scans to allow for further characterisation of this radioligand and examine the effects of [11C]PHNO mass carry-over and displaceable binding in the brain. This study aims to obtain data from 6 evaluable subjects.

Clinical Trial Description

A test-retest (TRT) investigation of [11C]PHNO in human is required to further characterise [11C]PHNO. [11C] PHNO possesses very high affinity for the D3 receptor, and therefore most clinical studies are conducted at D3 occupancies >10%. As [11C]PHNO kinetics in the target brain regions are moderately slow, considerable mass carry over may be present on a 2nd PET scan conducted on the same day. In addition there appears to be a significant displaceable binding component in the cerebellum, which, if not accounted for, will lead to a bias in the quantification of specific [11C]PHNO binding. The aim of this study is therefore to examine the effects of [11C]PHNO mass carry-over and displaceable binding in the cerebellum, on the quantification of [11C]PHNO PET data.

This will be an open label, non-randomised [11C]PHNO PET study using healthy volunteers. Each volunteer will undergo 4 [11C]PHNO PET scans:

1st and 2nd scans; TRT on the same day with a minimal gap between [11C]PHNO injections to examine the effects of PHNO mass carry over, 3rd scan >1 week later to determine the "true" TRT variability and a 4th scan will follow a 15mg dose of aripiprazole (a D2/D3 compound which allows the highest clinically acceptable blockade of central D2/D3 receptors) and will examine the amount of displaceable binding in the cerebellum, a proposed reference tissue for [11C]PHNO.

The scan data will be quantified as regional volumes of distribution (VT). ;

Study Design

Endpoint Classification: Pharmacodynamics Study, Intervention Model: Single Group Assignment, Masking: Open Label

Related Conditions & MeSH terms

• Depression
• Depressive Disorder

• NCT number: NCT01424449
• Study type: Interventional
• Source: GlaxoSmithKline
• Status: Completed
• Phase: Phase 1
• Start date: January 2010
• Completion date: July 2010