AzTrials
AzTrials

CannabisPhase 4NCT03555968

Effects of THC and Alcohol on Driving Performance

A Phase 4 study testing THC 0, THC 5 and THC 10 in people with Cannabis and Alcohol Drinking, run by Lakehead University.

Withdrawn

Withdrawn. The study stopped before anyone enrolled.

Official record
Search all trials

Trial summary

Low blood concentrations of THC and alcohol appear to have a minimal effect on driving performance.However, there is a gap in the literature about the combined effects of THC and alcohol. There is little empirical evidence to determine whether the combination of THC and alcohol could be additive or multiplicative. Read more about this study

Who is it for?
Ages 19 to 25 yearsHealthy volunteers can take part
Conditions the study is for
Cannabis, Alcohol Drinking, Accident, Traffic
What is being tested?
THC 0, THC 5 and THC 10
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
0 participants
Where
No sites listed yet
Study dates
Jul 2021to Dec 2021
Phase
Phase 4
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 19 to 25 years
  • All sexes
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • BMI >18 and <30
  • valid G2 or G Ontario driver's license
  • live on-campus or within 15 minutes drive of campus
  • speak fluent English

Who cannot join

  • history of cardiovascular or psychiatric disorders
  • current use of psychoactive medication
  • current drug or alcohol abuse problem
  • positive drug screen
  • BAC level > .000%

About this study

Official title: Determining the Combined Effects of THC and Alcohol on Driving Performance

Low blood concentrations of THC and alcohol appear to have a minimal effect on driving performance.However, there is a gap in the literature about the combined effects of THC and alcohol. There is little empirical evidence to determine whether the combination of THC and alcohol could be additive or multiplicative. This issue is particularly important when dealing with concentrations that are just below legal thresholds - it is important to identify if someone who may have consumed cannabis and alcohol, in quantities that do not exceed legal thresholds, may nonetheless be impaired to drive. Answering this question requires more research on the combined effects of THC and alcohol under tightly controlled experimental conditions. Hence, the purpose of this study is to determine the additive (or multiplicative) effect of standardized low doses of cannabis, in combination with low-doses of alcohol, on a number of outcome measures related to driving. The investigators will focus specifically on the effect of low blood concentrations of THC (0, 125, and 250 µg/kg) alone and in combination with low blood concentrations of alcohol (BAC 0%, .025%, and .049%). They shall determine the combined effect of THC and alcohol on physiological, cognitive, subjective measures of impairment, and simulated driving. This study will focus on younger adults because they have higher impaired driving rates than other age groups. As a secondary aim of the study, the investigators will examine whether previous driving and drug use history are correlated with driving decisions during the simulated drive and subjective measures. This study will contribute to the evidence base informing legislation, policy making, and law enforcement. This study is particularly timely given upcoming changes in legislation about cannabis, and because the combination of THC and alcohol, even below legal thresholds, may lead to impaired driving and crashes.

Being tested
THC 0, THC 5, THC 10, BAC 0, BAC .025
Keywords
THC, Alcohol, Driving, Dronabinol
Medical subject headings
Marijuana Abuse, Alcohol Drinking

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • THC 0Drug

    Also called Tetrahydrocannabinol, Dronabinol, Cannabis

    THC dose = 0mg

  • THC 5Drug

    Also called Tetrahydrocannabinol, Dronabinol, Cannabis

    THC dose = 5mg

  • THC 10Drug

    Also called Tetrahydrocannabinol, Dronabinol, Cannabis

    THC dose = 10mg

  • BAC 0Other

    Blood alcohol concentration = .000%

  • BAC .025Other

    Blood alcohol concentration = .025%

  • BAC .049Other

    Blood alcohol concentration = .049%

Study groups in NCT03555968
Study groupRoleWhat they receive
THC 0 + BAC 0Placebo comparatorParticipants will receive 0mg of THC in combination with blood alcohol concentrations of .000%.
Receives: Drug: THC 0; Other: BAC 0
THC 5 + BAC 0ExperimentalParticipants will receive 5mg of THC in combination with blood alcohol concentrations of .000%.
Receives: Drug: THC 5; Other: BAC 0
THC 10 + BAC 0ExperimentalParticipants will receive 10mg of THC in combination with blood alcohol concentrations of .000%.
Receives: Drug: THC 10; Other: BAC 0
THC 5 + BAC .025ExperimentalParticipants will receive 5mg of THC in combination with blood alcohol concentrations of .025%.
Receives: Drug: THC 5; Other: BAC .025
THC 10 + BAC .025ExperimentalParticipants will receive 125 µg/kg of THC in combination with blood alcohol concentrations of .025%.
Receives: Drug: THC 5; Other: BAC .025
THC 0 + BAC .049ExperimentalParticipants will receive 0 µg/kg of THC in combination with blood alcohol concentrations of .049%.
Receives: Drug: THC 0; Drug: THC 10; Other: BAC .025; Other: BAC .049
THC 5 + BAC .049ExperimentalParticipants will receive 5mg of THC in combination with blood alcohol concentrations of .049%.
Receives: Drug: THC 5; Other: BAC .049
THC 10 + BAC .049ExperimentalParticipants will receive 10mg of THC in combination with blood alcohol concentrations of .049%.
Receives: Drug: THC 5; Other: BAC .049
THC 0 + BAC .025ExperimentalParticipants will receive 0 µg/kg of THC in combination with blood alcohol concentrations of .025%.
Receives: Drug: THC 0; Drug: THC 10; Other: BAC .025; Other: BAC .049

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Demerit Points on Simulated Road Test

    Demerit points incurred for driving errors during a simulated a G2 exit exam (the final step in Ontario's graduated licensing framework) on a STISIM Drive 3-screen driving simulator; demerit points will be assigned in real-time by a member of the research team based on the Ontario Ministry of Transportation scoring scheme

    Measured: @2.5 hours

Secondary outcomes (9)

  1. Standard Deviation of Lane Position in Meters (STISIM Drive-Recorded Variable)

    Recorded by the STISIM simulator during the simulation

    Measured: @2.5 hours

  2. Mean and Standard Deviation of Velocity in Meters/Second (STISIM Drive-Recorded Variable)

    Recorded by the STISIM simulator during the simulation

    Measured: @2.5 hours

  3. Mean and Standard Deviation of Acceleration in Meters/Second (STISIM Drive-Recorded Variable)

    Recorded by the STISIM simulator during the simulation

    Measured: @2.5 hours

  4. Blood Pressure (Systolic/Diastolic mmHg)

    Systolic \& diastolic blood pressure via automated blood pressure cuff

    Measured: @25 minutes and 2 hours

  5. Heart Rate (BPM) & Heart Rate Variability via ECG

    Continuous heart rate in beats per minute via 3-lead electrocardiography recording; will allow for calculation of heart rate variability)

    Measured: Hour 0-3.5

  6. Electrical Brain Activity via EEG

    Continuous brain activity via electroencephalography recording

    Measured: Hour 0-3.5

  7. Median Response Time and Efficiency in Alerting, Orienting & Executive Attention as Measured by the Attention Network Test (in milliseconds)

    A computerized test to measure participants' performance in three separate components of attention: alerting, orienting, and executive attention

    Measured: @25 minutes and 2 hours

  8. Perceptual Motor Speed & Efficiency as Measured by Time (in seconds) to Complete Trail Making Tests A&B

    A pen and paper test to measure perceptual motor speed and efficiency

    Measured: @25 minutes and 2 hours

  9. Visual Analogue Scale of Perceived Effects

    Ratings of participants' current perceptions of mood and bodily sensations (22 items including anxiety, alertness, dizziness, dry mouth) driving (3 items related to current willingness to drive), and subjective impairment (at time 2 only; 6 items related to strength of effects, perceived performance on tests); all items measures from not at all>extremely or absent>severe on a 100 mm line

    Measured: @25 minutes and 2 hours

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted14 Jun 2018
  2. Study startJul 2021 (estimated)
  3. Primary completionDec 2021 (estimated)
  4. Study completionDec 2021 (estimated)

Why it stopped: Logistical issues

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 4
Primary purpose
Basic science
Allocation
Randomised
Intervention model
Factorial
Masking
Triple blind
Who is masked
Participant, Investigator, Outcomes assessor
Enrolment
0 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03555968
Sponsor's protocol ID
2018502
Status last verified
Apr 2022
First submitted
18 May 2018
Last updated
25 Apr 2022
Results posted
No
Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing THC 0, THC 5 and THC 10 in people with Cannabis and Alcohol Drinking, run by Lakehead University.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: withdrawn, as of the sponsor's last update on 25 Apr 2022. Status can change between updates, so confirm with the study contact before making plans.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

The study was withdrawn before enrolling participants, so there are no results.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Demerit Points on Simulated Road Test (time frame: @2.5 hours). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03555968.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 Apr 2022.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in