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Once Weekly D-cycloserine for Schizophrenia

Phase 4
Withdrawn
Conditions
Schizophrenia
Interventions
Drug: Placebo
Registration Number
NCT00964041
Lead Sponsor
Massachusetts General Hospital
Brief Summary

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.

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.

Recruitment & Eligibility

Status
WITHDRAWN
Sex
All
Target Recruitment
Not specified
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)

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlaceboParticipants will receive placebo weekly, one hour before any assessments, for eight weeks.
D-cycloserineD-cycloserineParticipants will receive D-cycloserine weekly, one hour before any assessments, for eight weeks.
Primary Outcome Measures
NameTimeMethod
Effect of repeated weekly dosing of D-cycloserine on performance on a standard cognitive battery.Baseline (Week 0) and End of Study (Week 8)
Secondary Outcome Measures
NameTimeMethod
Effects of weekly D-cycloserine dosing on negative symptoms at weeks 4 & 8 compared to placebo.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.Same Day (Single Dose - Week 1)
Assess the persistence of once-weekly D-cycloserine effects on memory consolidation measured at weeks 4 & 8.Week 4 and Week 8
Assess tolerability and side effects of weekly D-cycloserine compared to placeboWeekly measurements for 8 weeks

Trial Locations

Locations (1)

Massachusetts General Hospital

🇺🇸

Boston, Massachusetts, United States

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