Phase 2
N=199
The Impact and Detection of Driving Impairments Associated With Acute Cannabis Smoking
Cannabis Intoxication
Bottom Line
View on ClinicalTrials.gov: NCT02849587 ↗Enrolled (actual)
199
Serious AEs
0.0%
Results posted
Jan 2022
Primary outcome: Primary: Change in Composite Drive Score (CDS) From Pre-smoking Simulation — -.09; .12; .01; -.17 z-score — p=<0.001
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 2
- Interventions
- Cannabis (Drug)
- Age
- Adult · 21+ yrs
- Sex
- All
- Sponsor
- University of California, San Diego
- Primary completion
- Jun 2019
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Change in Composite Drive Score (CDS) From Pre-smoking Simulation |
-.09; .12; .01; -.17; .46; .21 | <0.001 sig |
| SECONDARY Simulator: Standard Deviation of Lateral Position (SDLP) |
1.09; 1.20; 1.11; 1.07; 1.24; 1.19 | 0.022 sig |
| SECONDARY Simulator: Speed Deviation |
2.13; 2.61; 2.63; 2.03; 3.04; 2.99 | 0.283 |
| SECONDARY Simulator: Correct Hits on mSuRT |
30.7; 29.9; 30.6; 30.9; 28.7; 30.3 | 0.0503 |
| SECONDARY Simulator: Car Following - Coherence |
.76; .73; .76; .79; .66; .71 | 0.024 sig |
| SECONDARY Simulator: Response Delay - Car Following |
2.92; 3.32; 3.58; 2.86; 3.44; 3.55 | 0.716 |
| SECONDARY Simulator: Distance From Lead Car - Car Following |
153; 156; 163; 143; 165; 164 | 0.005 sig |
| SECONDARY Tablet Assessment: Dual Attention Missed Switches |
0.095; 0.145; 0.167; 0.095; 0.194; 0.183 | .366 |
| SECONDARY Tablet Assessment: Lane Tracking Standard Deviation |
26.9; 30.9; 27.2; 28.7; 30.9; 32.1 | .225 |
| SECONDARY Tablet Assessment: Visual Spatial Learning Test Number Correct |
9.9; 9.7; 10.1; 9.1; 8.4; 9.3 | .592 |
| SECONDARY Tablet Assessment: Time Estimation |
0.75; 0.83; 0.77; 0.79; 0.89; 0.85 | .294 |
| SECONDARY Tablet Assessment: Balance |
0.358; 0.360; 0.356; 0.342; 0.376; 0.363 | .144 |
| SECONDARY THC Concentrations: Correlation Between Blood and Oral Fluid |
0.217; 0.414; 0.249 | 0.090 |
| SECONDARY THC Concentrations: Correlation Between Whole Blood and Breath |
0.134; -0.258; -0.176 | 0.300 |
Summary
This study was authorized by the California Legislature (Assembly Bill 266, the Medical Marijuana Regulation and Safety Act to help with detection of driving under the influence of cannabis. One hundred and eighty healthy volunteers will inhale smoked cannabis with either 0% (placebo), 5.9%, or 13.4% Δ9-tetrahydrocannabinol (THC) at the beginning of the day, and then complete driving simulations, iPad-based performance assessments, and bodily fluid draws (e.g., blood, saliva, breath) before the cannabis smoking and a number of times over the subsequent 6 hours after cannabis smoking. The purpose is to determine (1) the relationship of the dose of Δ9-THC on driving performance and (2) the duration of driving impairment in terms of hours from initial use, (3) if saliva or expired air can serve as a useful substitute for blood sampling of Δ9-THC, and (4) if testing using an iPad can serve as a useful adjunct to the standardized field sobriety test in identifying acute impairment from cannabis.
Eligibility Criteria
Inclusion Criteria
- Be a licensed driver.
- Need to have acuity of 20/40 or better, with or without correction on a Snellen Visual Acuity eye chart.
Exclusion Criteria
- At the discretion of the examining physician, individuals with significant cardiovascular, hepatic or renal disease, uncontrolled hypertension, and chronic pulmonary disease (eg, asthma, COPD) will be excluded.
- Unwillingness to abstain from cannabis for 2 days prior to screening and experimental visits
- Positive pregnancy test
- A positive result on toxicity screening for cocaine, amphetamines, opiates, and phencyclidine (PCP) will exclude individuals from participation.
- Unwilling to refrain from driving or operating heavy machinery for four hours after consuming study medication.
Data sourced from ClinicalTrials.gov (NCT02849587). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.