Psychopharmacology

, Volume 179, Issue 1, pp 144–150

A six-month, placebo-controlled trial of d-cycloserine co-administered with conventional antipsychotics in schizophrenia patients

  • Donald C. Goff
  • Lawrence Herz
  • Thomas Posever
  • Vivian Shih
  • Guochuan Tsai
  • David C. Henderson
  • Oliver Freudenreich
  • A. Eden Evins
  • Iftah Yovel
  • Hui Zhang
  • David Schoenfeld
Original Investigation

DOI: 10.1007/s00213-004-2032-2

Cite this article as:
Goff, D.C., Herz, L., Posever, T. et al. Psychopharmacology (2005) 179: 144. doi:10.1007/s00213-004-2032-2

Abstract

Rationale

d-Cycloserine, a partial agonist at the glycine site of the N-methyl-d-aspartate receptor, has demonstrated inconsistent efficacy for negative and cognitive symptoms of schizophrenia. The strongest evidence for efficacy has come from studies using d-cycloserine at a dose of 50 mg/day added to conventional antipsychotics in trials of 8 weeks duration or less.

Objective

To assess the efficacy for negative symptoms and cognitive impairment of d-cycloserine augmentation of conventional antipsychotics in a 6-month trial.

Methods

Fifty-five schizophrenia patients with prominent negative symptoms, treated with conventional antipsychotics, were randomly assigned to treatment with d-cycloserine 50 mg/day or placebo for 6 months in a double-blind, parallel group design.

Results

Twenty-six subjects completed the 6-month trial; drop-out rates did not differ between treatment groups. d-Cycloserine treatment did not differ from placebo treatment on any primary outcome measure at 8 or 24 weeks, including response of negative symptoms and performance on a cognitive battery. Serum d-cycloserine concentrations did not correlate with response of negative symptoms.

Conclusion

d-Cycloserine did not exhibit therapeutic effects in this trial, possibly reflecting the high drop-out rate, a narrow range of therapeutic serum concentrations, a modest magnitude of therapeutic effect for the selected outcome measures, or loss of efficacy over time. Because d-cycloserine is a partial agonist with relatively low affinity for the glycine site, the magnitude of potential therapeutic effect may be smaller than that achieved by the higher-affinity full agonists, glycine and d-serine.

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • Donald C. Goff
    • 1
    • 2
    • 3
  • Lawrence Herz
    • 4
  • Thomas Posever
    • 5
  • Vivian Shih
    • 3
    • 6
  • Guochuan Tsai
    • 7
  • David C. Henderson
    • 1
    • 3
  • Oliver Freudenreich
    • 1
    • 3
  • A. Eden Evins
    • 1
    • 3
  • Iftah Yovel
    • 1
    • 3
  • Hui Zhang
    • 8
  • David Schoenfeld
    • 3
    • 8
  1. 1.Schizophrenia ProgramMassachusetts General HospitalBostonUSA
  2. 2.Freedom Trail ClinicBostonUSA
  3. 3.Harvard Medical SchoolBostonUSA
  4. 4.Bedford Veteran’s Affairs Medical CenterBoston University Medical SchoolBostonUSA
  5. 5.Lemuel Shattuck HospitalTufts Medical SchoolBostonUSA
  6. 6.Pediatric Neurology ServiceMassachusetts General HospitalBostonUSA
  7. 7.McLean HospitalBelmontUSA
  8. 8.BiostatisticsMassachusetts General HospitalBostonUSA