NCT01832766

Brief Summary

Approximately 25% of people with schizophrenia abuse marijuana. These people may be using marijuana to self-medicate symptoms such as hallucinations (hearing or seeing things that are not heard or seen by others) or delusions (false beliefs i.e. people are harassing or persecuting them) or the depressed and anxious feelings brought on by these symptoms. Currently, it is unknown whether marijuana makes schizophrenia better or worse. Marijuana intoxication in people without schizophrenia generally causes decreased recall of words, may decrease reaction time and decrease inhibition. Additionally, marijuana may cause distractibility as demonstrated by difficulty keeping their eyes on a moving target and difficulty inhibiting their response to repetitive tones. However, marijuana may have different effects in schizophrenia. Receptors for cannabis (marijuana) are concentrated in the brain and maladjustment of the cannabinoid system may be associated with the difficulty in thinking found in schizophrenia. The proposed research project examines if clinical symptoms, learning, memory, inhibition and distractibility are improved or made worse by the acute ingestion of tetrahydrocannabinol (THC).

Trial Health

57
Monitor

Trial Health Score

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

Enrollment
13

participants targeted

Target at below P25 for phase_1 schizophrenia

Timeline
Completed

Started Jun 2005

Longer than P75 for phase_1 schizophrenia

Geographic Reach
1 country

1 active site

Status
terminated

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

June 1, 2005

Completed
4.9 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 1, 2010

Completed
1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

May 1, 2011

Completed
1.9 years until next milestone

First Submitted

Initial submission to the registry

March 25, 2013

Completed
22 days until next milestone

First Posted

Study publicly available on registry

April 16, 2013

Completed
2.4 years until next milestone

Results Posted

Study results publicly available

September 21, 2015

Completed
Last Updated

September 21, 2015

Status Verified

August 1, 2015

Enrollment Period

4.9 years

First QC Date

March 25, 2013

Results QC Date

June 30, 2014

Last Update Submit

August 18, 2015

Conditions

Schizophrenia

Keywords

schizophreniadronabinolP50cannabismemorysymptoms

Outcome Measures

Primary Outcomes (1)

  • P50 Auditory Evoked Potential

    electrophysiological measure of ability to filter extraneous stimuli measured as the amplitude of the evoked response to the second auditory stimulus divided by the amplitude of the evoked response to the first auditory stimulus in mV.

    2 hours after drug administration

Secondary Outcomes (1)

  • California Verbal Learning Test Change at 2 Hours From Baseline

    2 hours after drug administration

Other Outcomes (1)

  • Brief Psychiatric Rating Scale Change From Baseline at 1 Hour

    at 1 hour after drug administration

Study Arms (2)

dronabinol

ACTIVE COMPARATOR

dronabinol 10 mg one capsule by mouth at 8:00 a.m.

Drug: Dronabinol

sugar pill

PLACEBO COMPARATOR

one capsule given by mouth at 8:00 a.m.

Other: Placebo Comparator

Interventions

DronabinolDRUG

dronabinol 10 mg one capsule by mouth at 8:00 a.m.

Also known as: Marinol
dronabinol
Placebo ComparatorOTHER

one capsule given by mouth at 8:00 a.m.

Also known as: Sugar Pill
sugar pill

Eligibility Criteria

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

You may qualify if:

  • Male and females
  • and 50 years of age
  • Diagnosis of schizophrenia
  • Chronic cannabis users who have used for at least 1 year
  • Using cannabis at least once weekly
  • Currently being treated with antipsychotic medication
  • Must be on a the same dose of antipsychotic medication for at least 3 months.
  • Females of childbearing potential must use an adequate form of birth control while participating.
  • Participants will be required to have blood pressures greater than 90/60 and less than 140/90.

You may not qualify if:

  • Use of illicit drugs other than cannabis
  • Any psychiatric hospitalizations within 3 months
  • pregnancy in females
  • taking clozapine

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Colorado Denver

Aurora, Colorado, 80045, United States

Location

MeSH Terms

Conditions

SchizophreniaMarijuana Abuse

Interventions

DronabinolSugars

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic DisordersMental DisordersSubstance-Related DisordersChemically-Induced Disorders

Intervention Hierarchy (Ancestors)

CannabinoidsTerpenesHydrocarbonsOrganic ChemicalsCarbohydrates

Limitations and Caveats

early termination as recruitment of subjects with only cannabis use was difficult leading to small number of subjects analyzed

Results Point of Contact

Title
Lynn Johnson, Pharm.D.
Organization
University of Colorado Denver
lynn.johnson@ucdenver.edu
303 724 6221

Study Officials

  • Lynn Johnson, Pharm D

    University of Colorado, Denver

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
No

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

March 25, 2013

First Posted

April 16, 2013

Study Start

June 1, 2005

Primary Completion

May 1, 2010

Study Completion

May 1, 2011

Last Updated

September 21, 2015

Results First Posted

September 21, 2015

Record last verified: 2015-08

Locations

US(1)