Facilitation of NMDA Receptor Function in Patients With Schizophrenia and Co-morbid Alcoholism

January 12, 2018 updated by: Yale University

This placebo-controlled study is designed to evaluate the efficacy of glycine, an agonist of the glycine-B co-agonist site of the NMDA receptor, on alcohol consumption and craving as well as negative symptoms in schizophrenia.

Glycine will decrease the rewarding action of ethanol and reduce ethanol consumption. Also, glycine will improve negative symptoms and cognitive deficits in schizophrenia.

Study Overview

Status

Completed

Intervention / Treatment

Detailed Description

OBJECTIVE: Schizophrenia affects about 1% of the general population and is a highly disabling disease. Additionally, the rate of alcohol dependency for patients with schizophrenia is very high. There are no established treatments for alcohol dependency and negative symptoms in schizophrenia. This study will examine whether the addition of glycine to neuroleptic medications will help patients with schizophrenia and alcoholism decrease their drinking as well as improve negative symptoms.

RESEARCH PLAN: An abnormality of the glutamate neurotransmitter system has been hypothesized for both alcoholism and schizophrenia. Studies suggest that the amino acid glycine may improve alcohol dependency and symptoms of schizophrenia by acting on the N methyl D aspartate (NMDA) glutamate receptor. Glycine causes reversal of the effects of ethanol in animal studies and improves mood, social withdrawal and other so called "negative symptoms" of schizophrenia. Consequently, the use of glycine by patients with schizophrenia and alcohol dependency may potentially decrease alcohol craving and alcohol consumption and also improve certain symptoms of schizophrenia. The potential of glycine to improve both alcohol dependency and negative symptoms could represent an important step in the improvement of the quality of life for patients with schizophrenia.

METHODOLOGY/FINDINGS/RESULTS: In order to test this hypothesis, we will use a double blind, placebo controlled study and measure the number of drinks, the degree of craving for alcohol and symptoms of schizophrenia among other parameters. Our principal approach to analyses of medication effectiveness will be the application of the linear mixed effect model. The linear mixed effect model permits a flexible approach for studying change in individuals through time as a random effect, and does not require all patients to have data at all measured points. Our principal model of analysis includes treatment (placebo or glycine), as between subject factor, and time, as within subject factor. Compliance will be also included as a time varying independent variable. This project continues to recruit subjects.

Study Type

Interventional

Enrollment (Actual)

20

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Connecticut
      • West Haven, Connecticut, United States, 06516
        • VA Connecticut Healthcare System

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

21 years to 60 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • DSM-IV diagnosis of schizophrenia or schizoaffective disorder
  • DSM-IV diagnosis of alcohol dependence
  • Stable treatment with typical or atypical antipsychotics

Exclusion Criteria:

  • Axis I diagnosis other than alcohol dependence, schizophrenia, schizoaffective disorder, OCD, and PTSD.
  • current drug dependence
  • evidence of significant hepatocellular injury evidence by abnormal SGOT or SGPT levels
  • history of seizures
  • diabetes and medical conditions that would alter glycine metabolism
  • positive pregnancy test
  • treatment with clozapine, naltrexone or disulfiram

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Glycine
Glycine, 0.8 gr per kg given in two daily doses
Glycine, 0.8 gr per kg given in two daily doses
Placebo Comparator: placebo
placebo will be administered.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Self Reported Weekly Alcohol Consumption
Time Frame: 12 weeks
Percentage of drinking days and heavy drinking days using timeline follow back
12 weeks
Self Reported Weekly Alcohol Craving
Time Frame: 12 weeks
The Obsessive Compulsive Drinking Scale (OCDS) is consisted by 14 items rated 0 - 4. The minimum and maximum values possibly obtained in this scale are respectively 0 and 56, this last one, meaning the most craving possible experienced. It is a short and easy to administer scale (average of 5 minutes per self-rating), built to measure severity and improvement during alcoholism treatment trials.
12 weeks
Weekly Ratings of Negative/Positive Psychotic Symptoms
Time Frame: 12 weeks
The PANSS or the Positive and Negative Syndrome Scale is a medical scale used for measuring symptom severity of patients with schizophrenia. The patient is rated from 1 to 7 on 30 different symptoms based on the interview as well as reports of family members or primary care hospital workers. Of the 30 items included in the PANSS, 7 constitute a Positive Scale, 7 a Negative Scale, and the remaining 16 a General Psychopathology Scale.The scores for these scales are arrived at by summation of ratings across component items. Therefore, the potential ranges are 7 to 49 for the Positive and Negative Scales, and 16 to 112 for the General Psychopathology Scale. A higher score indicates more severe symptoms for each scale.
12 weeks
Baseline and End of Treatment Cognitive Functioning Measures (Hopkins)
Time Frame: 12 weeks
Hopkins Verbal Learning Test Assesses short term verbal learning and memory. Subscales include immediate recall (0-36), delayed recall (0-12) , and recognition (0-12). A higher score indicates better memory performance.
12 weeks

Secondary Outcome Measures

Outcome Measure
Time Frame
Weekly Drug Use
Time Frame: 12 weeks
12 weeks
Baseline and End of Treatment Quality of Life
Time Frame: 12 weeks
12 weeks
Baseline and End of Treatment Neurophysiological Measures
Time Frame: 12 weeks
12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Principal Investigator: Ismene Petrakis, M.D., Yale University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

June 1, 2003

Primary Completion (Actual)

December 1, 2015

Study Completion (Actual)

December 1, 2015

Study Registration Dates

First Submitted

June 15, 2006

First Submitted That Met QC Criteria

June 15, 2006

First Posted (Estimate)

June 20, 2006

Study Record Updates

Last Update Posted (Actual)

January 17, 2018

Last Update Submitted That Met QC Criteria

January 12, 2018

Last Verified

January 1, 2018

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Alcoholism

Clinical Trials on placebo

3
Subscribe