Randomized, Double-Blinded, Placebo Controlled Study of the Effects of Atomoxetine on Cognitive Function in Patients With Schizophrenia and Normal Controls Based on COMT Genotype
Overview
- Phase
- Phase 2
- Intervention
- Atomoxetine
- Conditions
- Schizophrenia
- Sponsor
- National Institute of Mental Health (NIMH)
- Enrollment
- 11
- Locations
- 1
- Primary Endpoint
- Changes in Functional Magnetic Resonance Imaging (fMRI) Blood-oxygen-level-dependent (Bold) Activity
- Status
- Terminated
- Last Updated
- 12 years ago
Overview
Brief Summary
This study will evaluate whether Atomoxetine improves cognition in healthy volunteers as well as patients with schizophrenia. Atomoxetine is a drug that has been Food and Drug Administration (FDA) approved for Attention Deficit Disorder and allegedly increase the amount of the neurotransmitter dopamine in the frontal cortex of the brain.
Detailed Description
Psychopharmacological modulation of the catecholaminergic system can enhance some aspects of cognitive function. For example, catechol-O-methyltransferase (COMT) inhibitors such as tolcapone can improve working memory/executive function. Similarly, modafinil, a catecholaminergic agonist with norepinephrine (NA) reuptake blocking properties, was also shown to improve delay-dependent working memory in mice. Differences in the response between individuals might be related to a number of factors, including variations in the genes. The recent finding that a polymorphism in the COMT gene, which produces a change in enzyme activity, accounts for 4% of the variance in performance of working memory tasks in humans suggest that COMT genotype may predict response to COMT inhibitors or to other dopaminergic agonists that increase catecholaminergic function in the frontal cortex. In the present investigation our goal is to examine, in normal controls and patients with schizophrenia, the effect of atomoxetine, a selective noradrenaline reuptake inhibitor that increases extracellular levels of dopamine in the frontal cortex, on cognitive function. We predict that both normal controls and patients with schizophrenia with the val/val genotype, which present higher COMT activity and, thus, lower extracellular dopamine concentrations in the frontal cortex, will have a significant improvement in working memory. Furthermore, in conjunction with other National Institute of Mental Health imaging protocols, we would like to examine the neurophysiological correlates related to working memory. We predict improved measures in prefrontal efficiency in subjects and patients specifically with the val/val genotype. The present protocol will provide new insights on the importance of this genetic polymorphism in the regulation of aminergic-controlled cognitive function in normal individuals. Furthermore, this protocol will test whether atomoxetine offers a new treatment, based on genotype, for cognitive impairment in schizophrenia. An Investigational New Drug (IND) waiver will be requested for the present study.
Investigators
Eligibility Criteria
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Arms & Interventions
Atomoxetine
Atomoxetine 80 mg final dose. Arm lasts 14 days. Schedule 25 mg Day 1 (or Day 22), 40 mg Day 2-3 (or Days 23-24), 60 mg Days 4-5 (or Days 25-26), 80 mg Days 6-14 (or Days 27-35). After 14 days, subjects undergo functional magnetic resonance imaging (MRI) and neuropsychological testing in addition to psychopathology ratings
Intervention: Atomoxetine
Atomoxetine
Atomoxetine 80 mg final dose. Arm lasts 14 days. Schedule 25 mg Day 1 (or Day 22), 40 mg Day 2-3 (or Days 23-24), 60 mg Days 4-5 (or Days 25-26), 80 mg Days 6-14 (or Days 27-35). After 14 days, subjects undergo functional magnetic resonance imaging (MRI) and neuropsychological testing in addition to psychopathology ratings
Intervention: Functional magnetic resonance imaging
Atomoxetine
Atomoxetine 80 mg final dose. Arm lasts 14 days. Schedule 25 mg Day 1 (or Day 22), 40 mg Day 2-3 (or Days 23-24), 60 mg Days 4-5 (or Days 25-26), 80 mg Days 6-14 (or Days 27-35). After 14 days, subjects undergo functional magnetic resonance imaging (MRI) and neuropsychological testing in addition to psychopathology ratings
Intervention: Neuropsychological Testing
Placebo
Placebo administered for 14 days. Schedule Atomoxetine 25 mg Placebo Day 1 (or Day 22), Atomoxetine 40 mg Placebo Day 2-3 (or Days 23-24), Atomoxetine 60 mg Placebo Days 4-5 (or Days 25-26), Atomoxetine 80 mg Placebo Days 6-14 (or Days 27-35). After 14 days, subjects undergo functional magnetic resonance imaging and neuropsychological testing in addition to psychopathology ratings
Intervention: Functional magnetic resonance imaging
Placebo
Placebo administered for 14 days. Schedule Atomoxetine 25 mg Placebo Day 1 (or Day 22), Atomoxetine 40 mg Placebo Day 2-3 (or Days 23-24), Atomoxetine 60 mg Placebo Days 4-5 (or Days 25-26), Atomoxetine 80 mg Placebo Days 6-14 (or Days 27-35). After 14 days, subjects undergo functional magnetic resonance imaging and neuropsychological testing in addition to psychopathology ratings
Intervention: Neuropsychological Testing
Placebo
Placebo administered for 14 days. Schedule Atomoxetine 25 mg Placebo Day 1 (or Day 22), Atomoxetine 40 mg Placebo Day 2-3 (or Days 23-24), Atomoxetine 60 mg Placebo Days 4-5 (or Days 25-26), Atomoxetine 80 mg Placebo Days 6-14 (or Days 27-35). After 14 days, subjects undergo functional magnetic resonance imaging and neuropsychological testing in addition to psychopathology ratings
Intervention: Placebo
Outcomes
Primary Outcomes
Changes in Functional Magnetic Resonance Imaging (fMRI) Blood-oxygen-level-dependent (Bold) Activity
Time Frame: 2 hours after the first or the second dose of Atomoxetine or placebo on 14th day
Main outcome measures were BOLD fMRI response (activation) while performing a prefrontal cortex-dependent task such as N-Back Working Memory with increasing levels of task difficulty. It was expected to have a greater level of activation in BOLD fMRI in schizophrenic patients with respect to normal volunteers, and a greater activation in individuals (either normal volunteers or patients) who share the val/val genotype with respect to the met/met genotype. Based on prior fMRI studies and on power analysis of neuropsychological variables, at least 28 and 26 subjects are respectively needed to achieve significant power in functional neuroimaging and neuropsychological studies.These sizes provide an 80% power to observe significant differences between drug conditions at the 0.05 level.
Changes in Cognitive Function Measured by Neuropsychological Testing
Time Frame: 2 hours after the first or the second dose of Atomoxetine or placebo on 14th day
Neuropsychological testing consists of a battery of 10-12 individual tests to measure cognitive function. We expect both a drug effect and a genotype effect on neuropsychological tasks that measure dorsolateral prefrontal cortex (DLPFC) executive function, mostly in individuals who share the val/val genotype with respect to the met/met genotype.
Secondary Outcomes
- Change in The Positive and Negative Syndrome Scale (PANSS)(At 14th and 35th days)
- Change in The Profile of Mood States(At 14th and 35th days)
- Change in The Hamilton Anxiety Rating Scale(At 14th and 35th days)