Once Weekly D-cycloserine for Schizophrenia

Overview

This is a parallel-group, placebo-controlled trial examining the cognitive effects at weeks 1, 4, & 8 of once-weekly oral D-cycloserine 50 mg added to a stable dose of antipsychotic for 8 weeks in adult outpatients with schizophrenia.

Full Title of Study: “Effects of Weekly Dosing of D-cycloserine on Cognitive Function in Individuals With Schizophrenia.”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Parallel Assignment
    • Primary Purpose: Treatment
    • Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
  • Study Primary Completion Date: June 2011

Detailed Description

In a previous placebo-controlled trial, investigators demonstrated significant improvement of negative symptoms with once-weekly D-cycloserine treatment. In addition, investigators found significant improvement of memory consolidation following the first dose; however, the effect on memory consolidation was lost after several weeks. The "practice effect" of weekly measurement of memory consolidation using repeated administration of the Logical Memory Test may have resulted in a "ceiling effect" which would obscure drug/placebo differences. In the current study, investigators propose to administer the Logical Memory Test at four-week intervals (weeks 1, 4 and 8) to avoid the ceiling effect. Additionally a measurement will be added of negative symptoms at week 4 to better characterize the time course of negative symptom improvement.

Hypotheses:

1. Assess the effects of a single dose of D-cycloserine 50 mg on memory consolidation as measured by the Logical Memory Test compared to placebo.

2. Assess the persistence of once-weekly D-cycloserine effects on memory consolidation measured at weeks 4 & 8.

3. Assess the effects of repeated weekly dosing of D-cycloserine on performance on a standard cognitive battery at week 8 compared to placebo.

4. Assess effects of weekly D-cycloserine dosing on negative symptoms at weeks 4 & 8 compared to placebo.

5. Assess tolerability and side effects of weekly D-cycloserine compared to placebo.

Interventions

  • Drug: D-cycloserine
    • 50 mg by mouth weekly, one hour before assessments, for eight weeks.
  • Drug: Placebo
    • Placebo by mouth, weekly, one hour before any assessments, each week for eight weeks.

Arms, Groups and Cohorts

  • Experimental: D-cycloserine
    • Participants will receive D-cycloserine weekly, one hour before any assessments, for eight weeks.
  • Placebo Comparator: Placebo
    • Participants will receive placebo weekly, one hour before any assessments, for eight weeks.

Clinical Trial Outcome Measures

Primary Measures

  • Effect of repeated weekly dosing of D-cycloserine on performance on a standard cognitive battery.
    • Time Frame: Baseline (Week 0) and End of Study (Week 8)

Secondary Measures

  • Effects of weekly D-cycloserine dosing on negative symptoms at weeks 4 & 8 compared to placebo.
    • Time Frame: Baseline (Week 0) and End of Study (Week 8)
  • Effect of a single dose of D-cycloserine 50 mg on memory consolidation as measured by the Logical Memory Test compared to placebo.
    • Time Frame: Same Day (Single Dose – Week 1)
  • Assess the persistence of once-weekly D-cycloserine effects on memory consolidation measured at weeks 4 & 8.
    • Time Frame: Week 4 and Week 8
  • Assess tolerability and side effects of weekly D-cycloserine compared to placebo
    • Time Frame: Weekly measurements for 8 weeks

Participating in This Clinical Trial

Inclusion Criteria

1. Male or female

2. Age 18-65 years

3. Diagnosis of schizophrenia or schizoaffective disorder, depressed type

4. Stable dose of antipsychotic for at least 4 weeks.

5. Able to provide informed consent

6. Able to complete a cognitive battery

Exclusion Criteria

1. Current treatment with clozapine

2. Dementia

3. Seizure disorder

4. Unstable medical illness

5. Active substance abuse

6. Pregnancy, nursing, or unwilling to use appropriate birth control measures during participation if female and fertile.

7. Severe renal insufficiency (Serum creatinine > 1.5 mg/dL)

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: 65 Years

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Massachusetts General Hospital
  • Collaborator
    • National Institute of Mental Health (NIMH)
  • Provider of Information About this Clinical Study
    • Principal Investigator: Donald C. Goff, MD, Director of the Schizophrenia Clinical and Research Program – Massachusetts General Hospital
  • Overall Official(s)
    • Donald C Goff, M.D., Principal Investigator, Massachusetts General Hospital

Clinical trials entries are delivered from the US National Institutes of Health and are not reviewed separately by this site. Please see the identifier information above for retrieving further details from the government database.

At TrialBulletin.com, we keep tabs on over 200,000 clinical trials in the US and abroad, using medical data supplied directly by the US National Institutes of Health. Please see the About and Contact page for details.