NCT00129441

Brief Summary

The purpose of this research study is to determine whether a short-term administration of an investigational study drug may provide evidence of improvement in cognitive functioning in a group of stable male subjects with schizophrenia.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
16

participants targeted

Target at below P25 for phase_2 schizophrenia

Timeline
Completed

Started Aug 2005

Typical duration for phase_2 schizophrenia

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

August 1, 2005

Completed
9 days until next milestone

First Submitted

Initial submission to the registry

August 10, 2005

Completed
1 day until next milestone

First Posted

Study publicly available on registry

August 11, 2005

Completed
2.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

January 1, 2008

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2008

Completed
3.8 years until next milestone

Results Posted

Study results publicly available

October 17, 2011

Completed
Last Updated

October 17, 2011

Status Verified

October 1, 2011

Enrollment Period

2.4 years

First QC Date

August 10, 2005

Results QC Date

May 25, 2011

Last Update Submit

October 14, 2011

Conditions

Schizophrenia

Keywords

schizophrenia

Outcome Measures

Primary Outcomes (5)

  • N-back Task - Reaction Time

    The N-back task is a sequential-letter memory task for which working memory load is varied, as the respondent must indicate when the current stimulus matches the one from 'n' steps earlier in the sequence. The dependent measure for the N-back task was performance in the 2-back condition, which provides the best index of performance and dorsolateral prefrontal cortex disturbances in subjects with schizophrenia.

    Week 4

  • N-back Task - Error Rate

    The N-back task is a sequential-letter memory task for which working memory load is varied, as the respondent must indicate when the current stimulus matches the one from 'n' steps earlier in the sequence. The dependent measure for the N-back task was performance in the 2-back condition, which provides the best index of performance and dorsolateral prefrontal cortex disturbances in subjects with schizophrenia.

    Week 4

  • AX Continuous Performance Test Task D-prime

    For the AX Continuous Performance Test, subjects are required to maintain an attentional set across a delay interval in order to overcome a prepotent response tendency (target responses are required when an X is presented but only in the context of a preceding A; non-target conditions are AY, BX and BY). The dependent measure was d-prime at the long delay (calculated as AX hits minus BX false alarms, which is particularly sensitive to context processing impairments in individuals with schizophrenia.

    Week 4

  • Preparing to Overcome Prepotency (POP) Task - Reaction Time

    The POP task is a cued stimulus-response reversal paradigm that, similar to the AX Continuous Performance Test, requires increases in cognitive control through the maintenance and use of context information to overcome prepotent response tendencies.

    Week 4

  • Preparing to Overcome Prepotency Task - Error Rate

    The POP task is a cued stimulus-response reversal paradigm that, similar to the AX Continuous Performance Test, requires increases in cognitive control through the maintenance and use of context information to overcome prepotent response tendencies.

    Week 4

Secondary Outcomes (3)

  • Brief Psychiatric Rating Scale Total Score

    Week 4

  • Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) Total Score

    Week 4

  • Repeatable Battery for the Assessment of Neuropsychological Status - Delayed Memory Subindex

    Week 4

Study Arms (2)

Merck L-830982

EXPERIMENTAL
Drug: Merck L-830982

Sugar pill

PLACEBO COMPARATOR
Drug: Placebo

Interventions

Merck L-830982DRUG

The initial dose of L-830982 was 3.0 mg twice daily (b.i.d.) the dosage increased to 5.0 mg b.i.d. at the end of week 1 and 8.0 mg b.i.d. at the end of week 2, which was continued for the remaining 2 weeks of the trial. Medications were dispensed weekly in blister packs by the hospital pharmacy.

Also known as: MK-0777
Merck L-830982
PlaceboDRUG

Medications were dispensed weekly in blister packs by the hospital pharmacy, using the same number of pills as those on active drug.

Sugar pill

Eligibility Criteria

Age18 Years - 50 Years
Sexmale
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Male participants
  • Between the ages of 18 and 50
  • Meet diagnostic criteria for schizophrenia or schizoaffective disorder
  • Are clinically stable for a minimum of 3 months on current dose of medication
  • Are unemployed (i.e., work less than 20 hours per week at competitive employment)

You may not qualify if:

  • Psychoactive substance dependence within the past 6 months or substance abuse within the past month
  • History of head trauma or other neurological disorder
  • Medical illness or medications, such as benzodiazepine treatment or HIV medications, that may be affected by study participation (the study doctor will discuss this with potential subjects)
  • Mental retardation
  • Seizure disorder
  • History of a heart attack, arrhythmia, or other heart disease

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Pittsburgh

Pittsburgh, Pennsylvania, 15213, United States

Location

Related Publications (3)

  • Lewis DA, Hashimoto T, Volk DW. Cortical inhibitory neurons and schizophrenia. Nat Rev Neurosci. 2005 Apr;6(4):312-24. doi: 10.1038/nrn1648.

    PMID: 15803162BACKGROUND

  • Lewis DA, Volk DW, Hashimoto T. Selective alterations in prefrontal cortical GABA neurotransmission in schizophrenia: a novel target for the treatment of working memory dysfunction. Psychopharmacology (Berl). 2004 Jun;174(1):143-50. doi: 10.1007/s00213-003-1673-x. Epub 2003 Dec 9.

    PMID: 15205885BACKGROUND

  • Lewis DA, Cho RY, Carter CS, Eklund K, Forster S, Kelly MA, Montrose D. Subunit-selective modulation of GABA type A receptor neurotransmission and cognition in schizophrenia. Am J Psychiatry. 2008 Dec;165(12):1585-93. doi: 10.1176/appi.ajp.2008.08030395. Epub 2008 Oct 15.

    PMID: 18923067RESULT

MeSH Terms

Conditions

Schizophrenia

Interventions

7-(1,1-dimethylethyl)-6-(2-ethyl-2H-1,2,4-triazol-3-ylmethoxy)-3-(2-fluorophenyl)-1,2,4-triazolo(4,3-b)pyridazine

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic DisordersMental Disorders

Limitations and Caveats

Small sample size; RBANS may lack appropriate sensitivity for short-term study; between-group differences in baseline clinical symptoms \& neuropsychological function; excluding those with more modest cognitive impairments (RBANS standard score \>90).

Results Point of Contact

Title
David A. Lewis, MD
Organization
University of Pittsburgh
lewisda@upmc.edu
(412) 246-6010

Study Officials

  • David A Lewis, MD

    University of Pittsburgh

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
No

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 10, 2005

First Posted

August 11, 2005

Study Start

August 1, 2005

Primary Completion

January 1, 2008

Study Completion

January 1, 2008

Last Updated

October 17, 2011

Results First Posted

October 17, 2011

Record last verified: 2011-10

Locations

US(1)