Adjuvant Treatment With a Glycine Uptake Inhibitor in Subjects With Chronic Schizophrenia (Study 172003)(COMPLETED)(P05695) (GIANT)

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Merck Sharp & Dohme Corp.
ClinicalTrials.gov Identifier:
NCT00725075
First received: July 28, 2008
Last updated: September 20, 2013
Last verified: September 2013
  Purpose

The purpose of this study is to determine whether Org 25935 is more effective

than placebo in improving negative symptoms in subjects with schizophrenia who

are concurrently treated with a stable dose of a second generation antipsychotic.


Condition Intervention Phase
Schizophrenia
Drug: Org 25935
Drug: Placebo
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: A Multi-center, Double-blind, Flexible-dose Efficacy Trial With Org 25935 Versus Placebo as add-on Therapy in Subjects With Predominant, Persistent Negative Symptoms of Schizophrenia Treated With a Stable Dose of a Second Generation Antipsychotic

Resource links provided by NLM:


Further study details as provided by Merck Sharp & Dohme Corp.:

Primary Outcome Measures:
  • Reduction of the total score (items 1-22) on the Scale for Assessment of Negative Symptoms (SANS) within twelve weeks treatment. [ Time Frame: 12 weeks treatment ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Reduction of composite scores on the Positive and Negative Syndrome Scale, Calgary Depression Scale for Schizophrenia, Extrapyramidal Symptoms Rating Scale, and computerized cognitive battery within twelve weeks treatment. [ Time Frame: twelve weeks treatment ] [ Designated as safety issue: No ]

Enrollment: 246
Study Start Date: April 2007
Study Completion Date: October 2008
Primary Completion Date: October 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Arm 1
Org 25935 (8-16 mg per day)
Drug: Org 25935

After screening, eligible subjects will be maintained on a stable dose of

Second Generation Antipsychotic (SGA) and will be randomized to

double-blind add-on treatment, i.e., twice daily (morning and evening) oral

administration of 4-8 mg Org 25935. This phase will last 84 (81-87) days for all subjects.

Experimental: Arm 2
Org 25935 (24-32 mg per day)
Drug: Org 25935
After screening, eligible subjects will be maintained on a stable dose of Second Generation Antipsychotic (SGA) and will be randomized to double-blind add-on treatment, i.e., twice daily (morning and evening) oral administration of 12-16 mg Org 25935. This phase will last 84 (81-87) days for all subjects.
Placebo Comparator: Arm 3
Placebo
Drug: Placebo
Placebo

Detailed Description:

The primary features of schizophrenia are characterized by positive (irrational

thoughts and/or behavior) and negative symptoms. Negative symptoms are the

gross absence of normal behavior and emotions, and usually include a general

lack of engagement, social withdrawal, and loss of goal-directed behavior.

Negative symptoms may strongly affect daytime activities and quality of life. The effects of currently available antipsychotics on negative symptoms are not satisfactory and leave much room for improvement. Org 25935 is an investigational drug that may help to correct the above characteristics of schizophrenia by facilitating the messenger function of an amino acid in the brain, called glutamate. Preliminary data suggest that lowered glutamate levels in schizophrenia are associated with a failure to activate relevant areas in the

forebrain and with prominent negative symptoms.

  Eligibility

Ages Eligible for Study:   18 Years to 55 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Clinical diagnosis of schizophrenia with predominant,
  • Negative symptoms,
  • Receiving stable treatment with one of the following antipsychotics: aripiprazole, olanzapine, quetiapine, risperidone, or ziprasidone

Exclusion Criteria:

  • Subjects with overt positive symptoms,
  • Extrapyramidal symptoms,
  • Depressive symptoms,
  • Suicidality, uncontrolled medical disease, or other psychiatric disorder other than schizophrenia as a primary diagnosis are excluded.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

No Contacts or Locations Provided
  More Information

No publications provided by Merck Sharp & Dohme Corp.

Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Merck Sharp & Dohme Corp.
ClinicalTrials.gov Identifier: NCT00725075     History of Changes
Other Study ID Numbers: P05695, 172003
Study First Received: July 28, 2008
Last Updated: September 20, 2013
Health Authority: Argentina: Administracion Nacional de Medicamentos, Alimentos y Tecnologia Medica
Austria: Federal Office for Safety in Health Care
Chile: Instituto de Salud Pública de Chile
Czech Republic: State Institute for Drug Control
Finland: Ethics Committee
France: Afssaps - Agence française de sécurité sanitaire des produits de santé (Saint-Denis)
Norway: Norwegian Medicines Agency
Russia: Ministry of Health of the Russian Federation

Keywords provided by Merck Sharp & Dohme Corp.:
Negative symptoms
Glycine Uptake inhibitor
Add-on treatment
Second Generation Antipsychotic

Additional relevant MeSH terms:
Schizophrenia
Schizophrenia and Disorders with Psychotic Features
Mental Disorders
Antipsychotic Agents
Tranquilizing Agents
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Central Nervous System Agents
Therapeutic Uses
Psychotropic Drugs

ClinicalTrials.gov processed this record on August 28, 2014