A Double-Blind Study of N-Acetylcysteine Augmentation in Serotonin Reuptake Inhibitor-Refractory Obsessive-Compulsive Disorder and Depression

Yale University0 sites10 target enrollmentJune 2006

Overview

Brief Summary

Obsessive-compulsive disorder (OCD) affects 2-3% of the population and leads to a great deal of suffering. Many patients benefit from established treatments, the mainstay of which are cognitive behavioral therapy and a group of antidepressant medications known as serotonin reuptake inhibitors. However, 20-30% of patients get minimal benefit from these established therapeutic strategies. New avenues of treatment are urgently needed.

Existing medications for obsessive-compulsive disorder affect the neurotransmitters serotonin or dopamine; but increasing evidence suggests that functional disruptions of a different neurotransmitter, glutamate, may contribute to some cases of OCD. The researchers are therefore interested in using medications that target glutamate as novel treatment options for those OCD patients who do not benefit from established treatments.

One such medication is the drug N-Acetylcysteine, whose glutamatergic antagonistic properties may be effective in reducing the glutamatergic hyperactivity that is thought to contribute to the pathophysiology of OCD and major depressive disorder (MDD).

Riluzole, which is FDA approved for amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease) is also a glutamatergic agent. There is evidence that riluzole possesses anti-depressant, anti-obsessional, and anti-anxiety properties.

The modulation of glutamatergic activity is a promising new approach to the treatment of mood disorders. The researchers are therefore now recruiting patients to participate in a double-blind, placebo-controlled trial of N-Acetylcysteine, added to whatever other OCD medications they are taking.

Detailed Description

Due to limited participation, this study has closed.

Registry

clinicaltrials.gov

Start Date

June 2006

End Date

April 2011

Last Updated

6 years ago

Study Type

Interventional

Study Design

Parallel

Sex

All

Investigators

Sponsor

Yale University

Responsible Party

Sponsor

Eligibility Criteria

Inclusion Criteria

•DSM-IV diagnosis of OCD, confirmed by SCID-IV; symptoms of at least 1 year duration
•moderate to severe OCD symptoms (Y-BOCS \> 16)
•documented failure of an adequate trial of an SSRI
•agreement to engage in a reliable form of birth control (women only)

Exclusion Criteria

•primary diagnosis of a psychotic disorder
•active substance abuse or dependence
•unstable medical condition
•prior exposure to N-Acetylcysteine
•prior psychosurgery
•pregnancy, breastfeeding, or intent to become pregnant during study
•liver function tests (LFTs) elevated to more than 2x the upper limit of normal
•evidence of active liver disease
•seizure disorder
•active suicidal ideation

Arms & Interventions

N-Acetylcysteine

Patients randomized to this arm will receive N-Acetylcysteine augmentation, at a standard dose titrated to 3000 mg within the first week, in addition to the medication regimen they are on at enrollment

Intervention: N-Acetylcysteine

placebo

Patients randomized to this arm will receive placebo, formulated to be indistinguishable from N-Acetylcysteine, in addition to the medication regimen they are on at study enrollment.

Intervention: placebo

Outcomes

Primary Outcomes

Yale-Brown Obsessive-Compulsive Scale (Y-BOCS)at Baseline

Time Frame: Baseline

The Y-BOCS is a 10 item clinician-rated scale used to both determine the severity of OCD and to monitor symptom improvement throughout the course of the study. The Y-BOCS, specifically measures the severity of symptoms of obsessive-compulsive disorder without being biased towards the type of obsessions or compulsions present. The scale includes questions about the amount of time spent on, how much impairment or distress experienced from, and how much resistance and control over these obsessive thoughts and compulsions. Each item is rated from 0 ("no symptoms") to 4 ("extreme symptoms") and yields a total possible score range from 0 to 40, with the following ranges indicating degree of severity: 0-7 = sub-clinical 8-15 = mild 16-23 = moderate 24-31 = severe 32-40 = extreme In this study, baseline ratings are compared to those of week 12 to produce a "percent of change" with positive percentages indicating a decrease in symptom severity.

Yale-Brown Obsessive-Compulsive Scale (Y-BOCS)at 12 Weeks

Time Frame: 12 Weeks

The Y-BOCS is a 10 item clinician-rated scale used to both determine the severity of OCD and to monitor symptom improvement throughout the course of the study. The Y-BOCS, specifically measures the severity of symptoms of obsessive-compulsive disorder without being biased towards the type of obsessions or compulsions present. The scale includes questions about the amount of time spent on, how much impairment or distress experienced from, and how much resistance and control over these obsessive thoughts and compulsions. Each item is rated from 0 ("no symptoms") to 4 ("extreme symptoms") and yields a total possible score range from 0 to 40, with the following ranges indicating degree of severity: 0-7 = sub-clinical 8-15 = mild 16-23 = moderate 24-31 = severe 32-40 = extreme In this study, baseline ratings are compared to those of week 12 to produce a "percent of change" with positive percentages indicating a decrease in symptom severity.