Driving Under the Influence of Cannabis
Conditions
Keywords
Cannabis, Driving, Biomarker
Brief summary
The relevance of driving under the influence of cannabis is becoming increasingly important in the context of legalization. However, the measurement of tetrahydrocannabinol (THC) blood concentration is an inadequate marker for assessing driving impairment. Currently, there is no reliable marker available for estimating the time of last cannabis inhalation, which would provide a promising tool for regulating driving under the influence of cannabis. This pilot study aims to explore potential biomarkers and factors that could approximate the timing of the last cannabis inhalation, with emphasis on the potential explanation of interindividual differences in THC pharmacokinetics and -dynamics. The results will assist future research aimed at improving the ability to distinguish between impaired and unimpaired cannabis users in road traffic. These findings are of significant importance for road safety and for society at large, as they may provide more objective markers for cannabis inhalation, thereby permitting a methodologically sound evaluation of driving under the influence of cannabis.
Interventions
DRUGParticipants will prepare their cannabis product ad libitum and inhale the prepared product as usual for a maximum of 15 minutes.
Participants will prepare and inhale their cannabis product ad libitum for a maximum of 15 minutes. Prior to inhaling cannabis (the baseline), and for three hours thereafter, biological samples (e.g., blood) will be collected. Participants will be asked to complete a series of questionnaires addressing their (subjective) neurocognitive function and well-being, as well as their self-rated driving ability and subjective cannabis effects.
Sponsors
University Psychiatric Clinics Basel, University of Basel, Basel, Switzerland
Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel, Switzerland
Biopharmacy, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland
Institute of Forensic Medicine, University of Basel, Basel, Switzerland
University of Basel
Study design
Allocation
NON_RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Experience of smoking cannabis products, on average once a week. This may be in combination with tobacco. * Age 18-65 years Possession of driving license in at least one of the categories A, B, A1; B1, F, G or M * Sufficient knowledge of German * No cannabis inhalation or nicotine consumption on study day * No alcohol consumption within the last 24 h
Exclusion criteria
* Participation in a trial with investigational drugs within 30 days * Current or previous major psychiatric disorder (e.g., major depression, schizophrenia spectrum disorder) * Pregnancy or breastfeeding * Intake of CYP2C9, CYP2C19, and CYP3A4-inducers in the last 4 weeks before the study visit, e.g. rifampicin (antibiotic), carbamazepine (anticonvulsant), phenobarbital (anticonvulsant), phenytoin (anticonvulsant) or inhibitors, such as amiodarone (class III antiarrhythmic medication), antifungal drugs such as fluconazole, miconazole, voriconazole and itraconazole, antibiotics such as clarithromycin and sulfamethoxazole, ritonavir (protease inhibitor) and grapefruit juice. * The following conditions: vasopressin deficiency, pituitary tumor, active malignancy, severe hyponatremia requiring treatment, congestive heart failure, liver cirrhosis.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Quantification of phytochemicals in cannabis sativa (e.g. cannabinoids and flavonoids) and their metabolites in human whole blood samples. | 24 months | Quantification of the blood concentration of cannabis sativa phytochemicals such as minor cannabinoids, cannabinoids, and flavonoids. Blood samples will be analyzed at baseline and several time-points (0, 10, 20, 60, 180) post consumption of cannabis. Concentrations will be reported as ng/mL whole blood. |
Secondary
| Measure | Time frame |
|---|---|
| Assessment of selected genetic polymorphisms in the genes known to interact with cannabinoids (i.e. CYP2C9, CYP2C19) by e.g. RT-PCR to evaluate their influence on cannabinoid plasma levels and the ability to predict cannabinoid metabolism and pharmaco | 24 months |
| Quantitation of biomarkers applicable to determine the activity of enzymes or transporters known to be involved in the handling of cannabinoids (e.g. 4-ß-hydroxycholesterol, Coproporphyrin I und Coproporphyrin III) | 24 months |
| Comparison of DNA methylation profiles on blood-derived DNA samples between regular and non-cannabis users by evaluating key CpG sites (e.g., in the MCU gene) that interplay with risk factors and mental health by e.g. targeted Illumina DNA methylation | 24 months |
| Analysis of the protein-bound and free fractions of the different cannabinoids and their metabolites using e.g. equilibrium dialysis or ultracentrifugation | 24 months |
| Targeted and untargeted analysis of endogenous biomarkers (e.g. endocannabinoids) using e.g. high-resolution mass-spectrometry | 24 months |
| Measurement of the expression levels of relevant genes e.g. cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2) in whole blood samples by e.g. RT-PCR to evaluate especially their correlation with cannabinoid plasma levels, metabolism, and ph | 24 months |
| The effects of cannabis inhalation on neurocognition by non-invasive, neurocognitive testing | 24 months |
| Self-reported mood as measured e.g. by the Bf-SR questionnaire. | 24 months |
| Usual reasons for cannabis use as measured e.g. by the Marijuana Motives Questionnaire (MMQ) | 24 months |
| Measurement of hormones and biomarkers involved in the regulation of fluid balance (e.g. plasma osmolality …) | 24 months |
| Measurement of hormones and biomarkers of the anterior and posterior pituitary gland (e.g., plasma oxytocin, neurophysin I, ACTH, TSH, prolactin …) | 24 months |
| Subjectively experienced effects of cannabis inhalation (e.g. subjective driving ability, psychological effects and well-being) assessed by questionnaires (e.g. VAS) | 24 months |
Countries
Switzerland
Contacts
Primary ContactUrs Duthaler, PhD
Outcome results
None listed