Tier 2 — strong

The Cognitive and Negative Symptoms in Schizophrenia Trial (CONSIST): the efficacy of glutamatergic agents for negative symptoms and cognitive impairments

Buchanan RW, Javitt DC, Marder SR, Schooler NR, Gold JM, McMahon RP, Heresco-Levy U, Carpenter WT
The American journal of psychiatry 2007 164(10):1593-1602

Bibliography

PubMed
PMID 17898352
DOI
10.1176/appi.ajp.2007.06081358
Funding
Indexed support: NIMH NIH HHS. See the publication for grant and funder details.
Competing interests
The accessible abstract does not establish the authors' competing interests; absence of a statement is not evidence of no conflicts.

Study snapshot

DesignRandomized controlled human intervention
ModelAdult humans
Sample157 adults across five sites
InterventionAdjunctive glycine, D-cycloserine or placebo; glycine regimen up to 60 g/day in the trial
Duration16 weeks
EndpointsSANS negative symptoms; Composite cognitive performance

What the study showed, in plain terms

The larger multicenter CONSIST trial did not find glycine generally effective for persistent negative symptoms or cognitive impairment. It is essential context for interpreting earlier small positive trials.

Key findings

  • Neither glycine nor D-cycloserine significantly improved the main outcomes over placebo.
  • Site-specific differences did not establish overall efficacy.

What this study can and cannot tell us

The findings apply to the enrolled schizophrenia/schizoaffective population and regimen.

They do not directly test sleep or low-dose supplementation in healthy people.

Related papers in the corpus

Tier 2
Effect of clozapine and adjunctive high-dose glycine in treatment-resistant schizophrenia
Potkin SG et al. · The American journal of psychiatry · 1999
Tier 2
High-dose glycine added to olanzapine and risperidone for the treatment of schizophrenia
Heresco-Levy U et al. · Biological psychiatry · 2004
Tier 2
Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia
Heresco-Levy U et al. · Archives of general psychiatry · 1999
Tier 2
Double-blind, placebo-controlled, crossover trial of glycine adjuvant therapy for treatment-resistant schizophrenia
Heresco-Levy U et al. · The British journal of psychiatry : the journal of mental science · 1996
Tier 2
Amelioration of negative symptoms in schizophrenia by glycine
Javitt DC et al. · The American journal of psychiatry · 1994
Tier 2
Adjunctive high-dose glycine in the treatment of schizophrenia
Javitt DC et al. · The international journal of neuropsychopharmacology · 2001

Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction