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Effects of Inhaled Cannabis on Driving Performance

Primary Purpose

Alcohol Drinking, Cannabis

Status
Completed
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Alcohol(oral) and placebo
Cannabis(THC)(Inhaled) and Placebo
Sponsored by
Gary R Gaffney
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional basic science trial for Alcohol Drinking focused on measuring Cannabis, Marijuana, Marihuana, Alcohol, Driving

Eligibility Criteria

21 Years - 55 Years (Adult)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

  • Healthy adult (age 21-55) men and women, based on medical and psychological evaluation
  • Currently valid unrestricted (except for vision correction) US driver's license
  • Licensed driver for at least the past two years
  • Drove at least 1300 miles in the past year, by self-report
  • Live within an 80 mile radius of NADS
  • Available for an overnight stay followed by a full-day study session for six sessions
  • Must be considered a light or moderate drinker according to Quantity-Frequency-Variability Scale (QFV)
  • Cannabis use with a minimum frequency averaging at least one day per quarter and no more than three days a week during the three months prior to study entry
  • Peripheral veins suitable for repeated venipuncture and/or placement of an intravenous catheter
  • Systolic blood pressure within a clinically normal range (120 ± 30 mmHg) and -diastolic blood pressure of 80 ± 20 mmHg..
  • Good command of written and spoken English
  • Female subjects with reproductive potential must agree to use (and/or have their partner use) one (1) acceptable method of birth control beginning at the screening visit throughout the study (including intervals between treatment periods/panels) and until 2 weeks after the last dose of study drug in the last treatment period. Acceptable methods of birth control include the following: intrauterine device (IUD-with or without local hormone release), diaphragm, spermicides, cervical cap, contraceptive sponge, oral contraceptives or condoms. Abstinence is an alternative lifestyle and subjects practicing abstinence may be included in the study.

Exclusion Criteria:

  • Presence of any clinically significant illness, as detected by history, physical examination, and/or laboratory tests, that might influence driving performance (e.g., seizures, sleep apnea, narcolepsy, vertigo, chronic fatigue syndrome) or put the subject at increased risk of adverse events (e.g., cardiac arrhythmia, hypertension)
  • History of a clinically significant adverse event associated with cannabis or alcohol intoxication
  • Donation of more than 450 mL of blood within 14 days of study drug administration
  • If female, pregnant or nursing
  • Currently interested in or participating in drug abuse treatment, or participated in drug abuse treatment within 60 days preceding study enrollment
  • Currently taking drugs that are contraindicated for use with study drugs
  • Requires any special equipment to aid in driving (ex. pedal extensions, hand brake or throttle, spinner wheel knobs or other non-standard equipment)
  • Significant history of motion sickness or demonstrates significant simulator sickness during practice drives at screening (SSQ). Subjects must have scores below the following values on the SSQ: Nausea < 21, Oculomotor <32, Disorientation < 15, and Total Score < 32.
  • Current alcohol or cannabis use disorder, as identified by the Alcohol Use Disorders Identification Test for alcohol or Cannabis Use Disorders Identification Test for cannabis.
  • History of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the subject from study participation
  • Prior participation in a driver impairment or distraction-related research study conducted at NADS that uses the same base drive.

Sites / Locations

  • National Advanced Driving Simulator

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm 4

Arm 5

Arm 6

Arm Type

Experimental

Experimental

Experimental

Experimental

Experimental

Experimental

Arm Label

0% THC with 0.065 g/dL BAC

2.5-3.5% THC with 0.065 g/dL BAC

6.0-7.5% THC and 0.065 g/dL BAC

2.5-3.5% THC with 0 g/dL BAC

6.0-7.5% THC with 0 g/dL BAC

0% THC with 0 g/dL BAC

Arm Description

Outcomes

Primary Outcome Measures

Driving Performance
Measured by standard deviation of lane position. Metrics of driving performance were modeled using the SAS GLM Select function to identify changes in driver performance. Numbers represents coefficients on the regression equation such that this increase would be expected for every unit increase. A unit for THC is 1 ng/ml and a unit for BAC is 0.01% BAC. In understanding the regression coefficients, for THC the units for the coefficient would be expressed as cm per (ng/ml of THC), and for BrAC the units for the coefficient would be expressed as cm per (0.01% BrAC). The overall regression equation would be represented as SDLP = Intercept + Cthc x THC + Cbrac x BrAC. The coefficients indicate the strength of the effect on driving performance with higher coefficients indicating larger effects relative to the concentrations. Coefficients of zero indicate no effect or interactive effect.

Secondary Outcome Measures

THC Concentration in Plasma Sample
Measurement of THC concentration levels in plasma over the course of each visit compared to that of the other visits.
THC Concentration Levels in Whole Blood
Measurement of THC concentration levels in whole blood over the course of each visit compared to that of the other visits.

Full Information

First Posted
June 4, 2012
Last Updated
April 30, 2018
Sponsor
Gary R Gaffney
Collaborators
National Highway Traffic Safety Administration (NHTSA), National Institute on Drug Abuse (NIDA)
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1. Study Identification

Unique Protocol Identification Number
NCT01620177
Brief Title
Effects of Inhaled Cannabis on Driving Performance
Official Title
Effects of Inhaled Cannabis on Driving Performance
Study Type
Interventional

2. Study Status

Record Verification Date
April 2018
Overall Recruitment Status
Completed
Study Start Date
July 2012 (undefined)
Primary Completion Date
March 2014 (Actual)
Study Completion Date
March 2014 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor-Investigator
Name of the Sponsor
Gary R Gaffney
Collaborators
National Highway Traffic Safety Administration (NHTSA), National Institute on Drug Abuse (NIDA)

4. Oversight

Data Monitoring Committee
Yes

5. Study Description

Brief Summary
The purpose of this study is to expand understanding of the effects of cannabis on driving performance with and without the presence of low levels of alcohol. This project will involve the development a of a protocol and driving environment that is sensitive to the effects of cannabis on driving performance by building on prior driving situations used previously for testing the effects of alcohol on driving.
Detailed Description
Individuals will be recruited who are currently users of cannabis and alcohol to participate in this study. They will undergo a physical exam at screening. There will be six study visits where the subject will arrive at the Clinical Research Unit(University of Iowa Hospitals & Clinics) the night before dosing. At each visit subjects will be receive one of the following six dosing regimens: placebo alcohol with placebo cannabis; placebo alcohol with low-dose cannabis, placebo alcohol with higher-dose of cannabis, low dose alcohol with placebo cannabis; low dose alcohol with low dose cannabis, low dose alcohol with higher-dose of cannabis. After dosing, participants will have provide saliva samples and blood drawn periodically to check cannabis levels and will complete a driving simulation. After completing the drive, additional saliva samples and blood draws will occur and participants will be monitored until it is safe to transport home.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Alcohol Drinking, Cannabis
Keywords
Cannabis, Marijuana, Marihuana, Alcohol, Driving

7. Study Design

Primary Purpose
Basic Science
Study Phase
Not Applicable
Interventional Study Model
Crossover Assignment
Masking
ParticipantInvestigatorOutcomes Assessor
Allocation
Randomized
Enrollment
98 (Actual)

8. Arms, Groups, and Interventions

Arm Title
0% THC with 0.065 g/dL BAC
Arm Type
Experimental
Arm Title
2.5-3.5% THC with 0.065 g/dL BAC
Arm Type
Experimental
Arm Title
6.0-7.5% THC and 0.065 g/dL BAC
Arm Type
Experimental
Arm Title
2.5-3.5% THC with 0 g/dL BAC
Arm Type
Experimental
Arm Title
6.0-7.5% THC with 0 g/dL BAC
Arm Type
Experimental
Arm Title
0% THC with 0 g/dL BAC
Arm Type
Experimental
Intervention Type
Drug
Intervention Name(s)
Alcohol(oral) and placebo
Other Intervention Name(s)
Ethanol, Ethyl Alcohol
Intervention Description
Subjects will be dosed to an approximate peak BAC of 0.065%. Subjects will be tested on the decline such that subjects will be at or above the goal BAC (0.05%) throughout the drive
Intervention Type
Drug
Intervention Name(s)
Cannabis(THC)(Inhaled) and Placebo
Other Intervention Name(s)
Marihuana, Marijuana
Intervention Description
Cannabis vapor is produced from 500 mg either placebo (0% THC), approximately 2.5-3.5% THC (low dose), or approximately 6.0-7.5% THC (high dose) bulk cannabis plant material to yield doses of approximately 0, 12.5-17.5, or 30-37.5 mg THC
Primary Outcome Measure Information:
Title
Driving Performance
Description
Measured by standard deviation of lane position. Metrics of driving performance were modeled using the SAS GLM Select function to identify changes in driver performance. Numbers represents coefficients on the regression equation such that this increase would be expected for every unit increase. A unit for THC is 1 ng/ml and a unit for BAC is 0.01% BAC. In understanding the regression coefficients, for THC the units for the coefficient would be expressed as cm per (ng/ml of THC), and for BrAC the units for the coefficient would be expressed as cm per (0.01% BrAC). The overall regression equation would be represented as SDLP = Intercept + Cthc x THC + Cbrac x BrAC. The coefficients indicate the strength of the effect on driving performance with higher coefficients indicating larger effects relative to the concentrations. Coefficients of zero indicate no effect or interactive effect.
Time Frame
Through entire drive, 0.5-1.3 hr post cannabis administration.
Secondary Outcome Measure Information:
Title
THC Concentration in Plasma Sample
Description
Measurement of THC concentration levels in plasma over the course of each visit compared to that of the other visits.
Time Frame
-0.7 hr, 0.25hr, 1.1 hr, 2 hr, 3 hr, 4.5 hr, 6 hr, 8 hr post cannabis administration
Title
THC Concentration Levels in Whole Blood
Description
Measurement of THC concentration levels in whole blood over the course of each visit compared to that of the other visits.
Time Frame
-0.7 hr, 0.25hr, 1.1 hr, 2 hr, 3 hr, 4.5 hr, 6 hr, 8 hr post cannabis

10. Eligibility

Sex
All
Minimum Age & Unit of Time
21 Years
Maximum Age & Unit of Time
55 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: Healthy adult (age 21-55) men and women, based on medical and psychological evaluation Currently valid unrestricted (except for vision correction) US driver's license Licensed driver for at least the past two years Drove at least 1300 miles in the past year, by self-report Live within an 80 mile radius of NADS Available for an overnight stay followed by a full-day study session for six sessions Must be considered a light or moderate drinker according to Quantity-Frequency-Variability Scale (QFV) Cannabis use with a minimum frequency averaging at least one day per quarter and no more than three days a week during the three months prior to study entry Peripheral veins suitable for repeated venipuncture and/or placement of an intravenous catheter Systolic blood pressure within a clinically normal range (120 ± 30 mmHg) and -diastolic blood pressure of 80 ± 20 mmHg.. Good command of written and spoken English Female subjects with reproductive potential must agree to use (and/or have their partner use) one (1) acceptable method of birth control beginning at the screening visit throughout the study (including intervals between treatment periods/panels) and until 2 weeks after the last dose of study drug in the last treatment period. Acceptable methods of birth control include the following: intrauterine device (IUD-with or without local hormone release), diaphragm, spermicides, cervical cap, contraceptive sponge, oral contraceptives or condoms. Abstinence is an alternative lifestyle and subjects practicing abstinence may be included in the study. Exclusion Criteria: Presence of any clinically significant illness, as detected by history, physical examination, and/or laboratory tests, that might influence driving performance (e.g., seizures, sleep apnea, narcolepsy, vertigo, chronic fatigue syndrome) or put the subject at increased risk of adverse events (e.g., cardiac arrhythmia, hypertension) History of a clinically significant adverse event associated with cannabis or alcohol intoxication Donation of more than 450 mL of blood within 14 days of study drug administration If female, pregnant or nursing Currently interested in or participating in drug abuse treatment, or participated in drug abuse treatment within 60 days preceding study enrollment Currently taking drugs that are contraindicated for use with study drugs Requires any special equipment to aid in driving (ex. pedal extensions, hand brake or throttle, spinner wheel knobs or other non-standard equipment) Significant history of motion sickness or demonstrates significant simulator sickness during practice drives at screening (SSQ). Subjects must have scores below the following values on the SSQ: Nausea < 21, Oculomotor <32, Disorientation < 15, and Total Score < 32. Current alcohol or cannabis use disorder, as identified by the Alcohol Use Disorders Identification Test for alcohol or Cannabis Use Disorders Identification Test for cannabis. History of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the subject from study participation Prior participation in a driver impairment or distraction-related research study conducted at NADS that uses the same base drive.
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Gary G Gaffney, M.D.
Organizational Affiliation
National Advanced Driving Simulator
Official's Role
Principal Investigator
Facility Information:
Facility Name
National Advanced Driving Simulator
City
Iowa City
State/Province
Iowa
ZIP/Postal Code
52242
Country
United States

12. IPD Sharing Statement

Citations:
PubMed Identifier
26144593
Citation
Hartman RL, Brown TL, Milavetz G, Spurgin A, Pierce RS, Gorelick DA, Gaffney G, Huestis MA. Cannabis effects on driving lateral control with and without alcohol. Drug Alcohol Depend. 2015 Sep 1;154:25-37. doi: 10.1016/j.drugalcdep.2015.06.015. Epub 2015 Jun 23.
Results Reference
result
PubMed Identifier
26019183
Citation
Hartman RL, Brown TL, Milavetz G, Spurgin A, Gorelick DA, Gaffney G, Huestis MA. Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol. Clin Chem. 2015 Jun;61(6):850-69. doi: 10.1373/clinchem.2015.238287. Epub 2015 May 27.
Results Reference
result
PubMed Identifier
26257143
Citation
Hartman RL, Brown TL, Milavetz G, Spurgin A, Gorelick DA, Gaffney G, Huestis MA. Controlled vaporized cannabis, with and without alcohol: subjective effects and oral fluid-blood cannabinoid relationships. Drug Test Anal. 2016 Jul;8(7):690-701. doi: 10.1002/dta.1839. Epub 2015 Aug 10.
Results Reference
result
PubMed Identifier
26889769
Citation
Hartman RL, Brown TL, Milavetz G, Spurgin A, Pierce RS, Gorelick DA, Gaffney G, Huestis MA. Cannabis effects on driving longitudinal control with and without alcohol. J Appl Toxicol. 2016 Nov;36(11):1418-29. doi: 10.1002/jat.3295. Epub 2016 Feb 18.
Results Reference
result

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Effects of Inhaled Cannabis on Driving Performance

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