Dose-response of Cannabis and Driving

Sponsor
Centre for Addiction and Mental Health (Other)
Overall Status
Recruiting
CT.gov ID
NCT03656029
Collaborator
(none)
50
1
4
14.9
3.4

Study Details

Study Description

Brief Summary

Epidemiological studies have established a link between collisions while driving and cannabis use. With the changing legal landscape around cannabis, there is much interest in determining per se limits of cannabis while driving. The present study will evaluate driving on a driving simulator after smoking placebo or cannabis with 3 different levels of THC. THC is the active component in cannabis and blood, urine and oral fluid levels of THC will be correlated with driving impairment.

Condition or Disease Intervention/Treatment Phase
Phase 2

Detailed Description

Participants will attend the laboratory for 4 separate sessions, separated by about a week. In each session, participants will receive one of 3 doses of smoked cannabis or a placebo. Participants will not know which dose they are receiving. Participants will complete questionnaires, do cognitive tests and drive on a driving simulator before and after smoking the cannabis or placebo cigarette. Blood, urine and oral fluid will be collected throughout the 7-8 hour session to determine levels of THC and its metabolites. These values will be correlated with measures of driving impairment.

Study Design

Study Type:
Interventional
Anticipated Enrollment :
50 participants
Allocation:
Randomized
Intervention Model:
Crossover Assignment
Intervention Model Description:
This will be a within-subjects, counterbalanced, placebo-controlled study of placebo or 3 doses of cannabisThis will be a within-subjects, counterbalanced, placebo-controlled study of placebo or 3 doses of cannabis
Masking:
Double (Participant, Investigator)
Primary Purpose:
Basic Science
Official Title:
Dose-dependent Effects of Smoked Cannabis on Simulated Driving Performance
Actual Study Start Date :
Jun 4, 2021
Anticipated Primary Completion Date :
Aug 31, 2022
Anticipated Study Completion Date :
Aug 31, 2022

Arms and Interventions

Arm Intervention/Treatment
Placebo Comparator: Placebo

Participants will smoke a single smoked placebo (<0.1% THC) cannabis cigarette

Drug: Placebo
Participants will smoke a placebo cigarette

Active Comparator: low dose

Participants will smoke a single low dose (6.25% THC) of smoked cannabis cigarette

Drug: Cannabis
Participants will smoke as much of the cigarette as they wish

Active Comparator: middle dose

Participants will smoke a single intermediate dose (12.5% THC) of smoked cannabis cigarette

Drug: Cannabis
Participants will smoke as much of the cigarette as they wish

Active Comparator: high dose

Participants will smoke a single high dose (22% THC) of smoked cannabis cigarette

Drug: Cannabis
Participants will smoke as much of the cigarette as they wish

Outcome Measures

Primary Outcome Measures

  1. Mean speed [Change in speed of driving between the time before smoking the cigarette and either 30 or 90 minutes after smoking the cigarette]

    Speed of driving the simulator

Secondary Outcome Measures

  1. Standard deviation of lateral position [Change in measure from before smoking the cigarette to either 30 or 90 minutes after smoking]

    Driving measures

  2. reaction time [Change in measure from before smoking the cigarette to either 30 or 90 minutes after smoking]

    Driving measures

  3. Blood concentrations of THC and metabolites [Change from before smoking cigarette to various time points after smoking: 5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 2hours, 3 hours, 4 hours, 5 hours and 6 hours]

    Blood will be taken to determine how much THC entered the blood

  4. Oral fluid concentrations of THC and metabolites [Change from levels before smoking to 4 time points after smoking: 30 minutes, 90 minutes, 2 hours and 6 hours]

    Participants will provide oral fluid to determine how much THC is in the oral fluid

  5. Systolic and Diastolic Blood pressure [Change from before smoking to a number of time points after smoking: 5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 2hours, 3 hours, 4 hours, 5 hours and 6 hours]

    Vital signs

  6. Heart rate [Change from before smoking to a number of time points after smoking: 5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 2hours, 3 hours, 4 hours, 5 hours and 6 hours]

    Vital signs

  7. Respirations [Change from before smoking to a number of time points after smoking: 5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 2hours, 3 hours, 4 hours, 5 hours and 6 hours]

    Vital signs

  8. Temperature [Change from before smoking to a number of time points after smoking: 5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 2hours, 3 hours, 4 hours, 5 hours and 6 hours]

    Vital signs

  9. Visual Analog Scales [Change from before smoking to a number of time points after smoking: 5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 2hours, 3 hours, 4 hours, 5 hours and 6 hours]

    Tests designed to assess the degree of subjective effects of the drug. The questions will be scored on a scale from 0 to 100 and will consist of: 'I like this drug effect', 'this feels like cannabis', 'I feel this effect', 'I feel this high', 'I feel the good effects', 'I feel the bad effects', 'I feel the rush'

  10. Verbal free recall test [Change from pre-smoking levels to those observed 60 minutes after smoking]

    Test of memory: Participants will be asked to recall words that are read from a list

  11. Useful field of view [Change from pre-smoking levels to those observed 60 minutes after smoking]

    A computer test for visual processing speed, selective and divided attention

Eligibility Criteria

Criteria

Ages Eligible for Study:
19 Years to 45 Years
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
Yes
Inclusion Criteria:
  • Near daily use of cannabis (1-5 days/week) confirmed by self-report and urine screening

  • Has held a class G2 or G licence (or equivalent from another jurisdiction) for at least 12 months

  • Willing to abstain from using cannabis for 72 hours prior to each practice or test session

  • Willing to abstain from alcohol for 48 hours prior to each session, and to abstain from all other drugs not medically required for the duration of the study (beginning 48 hours prior to the practice session)

  • Provides written and informed consent

Exclusion Criteria:
  • Diagnosis of severe medical or psychiatric condition

  • Meets criteria for current or lifetime alcohol or other substance use disorder, except tobacco use disorder and caffeine use disorder

  • Regular user of medication that may affect cognitive functioning and/or driver performance

  • Family history of schizophrenia or other psychotic disorder

  • Pregnant, looking to become pregnant, or breastfeeding

Contacts and Locations

Locations

Site City State Country Postal Code
1 Center for Addiction and Mental Health Toronto Ontario Canada M5S 2S1

Sponsors and Collaborators

  • Centre for Addiction and Mental Health

Investigators

  • Principal Investigator: Bruna Brands, PhD, Centre for Addiction and Mental Health

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
Centre for Addiction and Mental Health
ClinicalTrials.gov Identifier:
NCT03656029
Other Study ID Numbers:
  • 007-2018
First Posted:
Sep 4, 2018
Last Update Posted:
Sep 5, 2021
Last Verified:
Aug 1, 2021
Individual Participant Data (IPD) Sharing Statement:
No
Plan to Share IPD:
No
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No
Product Manufactured in and Exported from the U.S.:
Yes
Additional relevant MeSH terms:

Study Results

No Results Posted as of Sep 5, 2021