In-Vehicle Real-Time Cannabis Influenced Driving Detection

NCT07401628 | Recruiting

• 1 other identifier: 2025-01590
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate whether in-vehicle sensor data can be used to detect cannabis-impaired driving in healthy adult recreational cannabis users. The study aims to assess whether changes in vehicle, driver, and physiological sensor data can distinguish sober driving from cannabis-impaired driving, and how driving performance changes from baseline to approximately 1 to 6 hours after controlled cannabis consumption. Researchers will compare driving behavior and in-vehicle sensor data from participants who receive controlled cannabis administration with data from a randomized reference group without cannabis exposure, to determine whether cannabis-related impairment driving can be identified on the basis of machine learning. Participants will complete screening and baseline assessments and drive an instrumented vehicle on a closed test track under sober conditions. Participants assigned to the experimental arm will receive controlled cannabis administration, while participants in the reference arm will receive no intervention. All participants will perform repeated standardized driving sessions over several hours and complete traffic-medical, traffic-psychological, and in-vehicle pre-driving tests. Biological samples and in-vehicle sensor data will be collected throughout the study.

Conditions

Driving Under the Influence; Cannabis-impaired Driving

Outcome Measures

Primary Outcomes (1)

• Diagnostic accuracy (AUROC) of a multimodal machine-learning model for detection of cannabis-impaired driving

  Area under the receiver operating characteristic curve (AUROC) of a single machine-learning classifier that integrates multimodal in-vehicle data (including vehicle controller area network \[CAN\] data, driver monitoring camera \[DMC\] features, and physiological signals). All modalities are combined into one predictive model, and performance is reported as one aggregated AUROC value distinguishing non-impaired (sober) driving from cannabis-impaired driving.

  Baseline (sober driving) and up to 6 hours after cannabis administration in the experimental arm, with matched time points in the reference arm.

Secondary Outcomes (17)

• Diagnostic accuracy (AUROC) using CAN data

  Baseline (sober driving) and approximately 1-2, 3-4, and 5-6 hours after cannabis administration in the experimental arm, with matched time points in the reference arm.

• Diagnostic accuracy (AUROC) using DMC data

  Baseline (sober driving) and approximately 1-2, 3-4, and 5-6 hours after cannabis administration in the experimental arm, with matched time points in the reference arm.

• Diagnostic accuracy (AUROC) of a physiology-based machine-learning model for detection of cannabis-impaired driving

  Baseline (sober driving) and approximately 1-2, 3-4, and 5-6 hours after cannabis administration in the experimental arm, with matched time points in the reference arm.

• Change in driving behavior derived from vehicle CAN data

  Baseline (sober driving) and approximately 1-2, 3-4, and 5-6 hours after cannabis administration in the experimental arm, with matched time points in the reference arm.

• Change in driver gaze behavior derived from DMC data

  Baseline (sober driving) and approximately 1-2, 3-4, and 5-6 hours after cannabis administration in the experimental arm, with matched time points in the reference arm.

Study Arms (2)

Controlled Cannabis Administration

EXPERIMENTAL

Participants assigned to this arm receive a single, controlled inhalative administration of cannabis by smoking a THC-containing joint with a target dose of approximately 0.67 mg THC per kg body weight. Participants complete standardized driving sessions in an instrumented vehicle on a closed test track under sober baseline conditions and repeatedly after cannabis administration (approximately 1-6 hours post-dose). All driving sessions are conducted with a certified driving instructor seated in the front passenger seat with access to dual pedals, allowing immediate intervention if required. Multimodal in-vehicle sensor data, physiological signals, driving performance measures, and biological samples are collected throughout the study.

Drug: Cannabis (THC)

Reference (No Cannabis)

NO INTERVENTION

Participants assigned to this reference arm receive no cannabis administration. They complete the same screening procedures, standardized driving sessions, assessments, and data collection as the experimental group under sober conditions, following the same schedule and time points. All driving sessions are conducted with a certified driving instructor seated in the front passenger seat with access to dual pedals, ensuring identical safety conditions. This arm serves as a non-impaired reference for comparison of driving behavior and in-vehicle sensor data.

Interventions

Cannabis (THC) DRUG

Participants assigned to the experimental arm receive a single, controlled inhalative administration of cannabis by smoking a THC-containing joint (target dose 0.67 mg THC per kg body weight; cannabis flowers with 15-18% THC).

Controlled Cannabis Administration

Eligibility Criteria

• Age: 21 Years+
• Gender Eligibility Details: Pregnancy test is required for females
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Informed consent as documented by signature
• Recreational cannabis-consumption (more than once per month)
• In possession of a definite Swiss or European Union (EU) driving license
• At least 21 years old
• Active, regular driving a car in the last 6 months
• Must be in good health condition
• No special equipment needed when driving (special seats, levers, etc.)
• Fluent in (Swiss) German and no speech impairment

You may not qualify if:

• Health concerns where cannabis consumption is contra-indicated (such as: high blood pressure, psychiatric problems (e.g. psychosis, depression, attention-deficit conditions, etc.)
• Cannabis-abstinence or excessive consumption, , assessed using the Cannabis Use Disorders Identification Test-Revised (CUDIT-R)
• For women: pregnancy or breastfeeding or if intention to become pregnant during study period (time between telephone screening and study day (visit 2)
• Alcohol misuse or excessive alcohol consumption habits/risky drinking behaviour, assessed using the Alcohol Use Disorders Identification Test (AUDIT) and/or phosphatidylethanol (PEth) in capillary blood \> 200 ng/mL at first visit
• If breath alcohol test is positive at Visit 1 or Visit 2 (study day)
• Consumption of drugs of abuse (others than cannabis) within 4 weeks before the study
• Consumption of medications / pharmaceutical drugs which interfere with driving ability
• Inability to follow the procedures of the study, e.g., due to language

Sponsors & Collaborators

• University of Bern: lead
• ETH Zurich: collaborator
• University of St.Gallen: collaborator

Study Sites (1)

Institute for Forensic Medicine, Forensic Chemistry and Toxicology University of Bern

Bern, 3008, Switzerland

RECRUITING

MeSH Terms

Conditions

Driving Under the Influence

Interventions

nabiximols; Dronabinol

Condition Hierarchy (Ancestors)

Criminal Behavior; Behavior; Dangerous Behavior

Intervention Hierarchy (Ancestors)

Cannabinoids; Terpenes; Hydrocarbons; Organic Chemicals

Study Officials

• Wolfgang Weinmann, Prof. Dr.

  Institute for Forensic Medicine, Forensic Chemistry and Toxicology University of Bern

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Wolfgang Weinmann, Prof. Dr.

CONTACT

+41 31 684 01 61; wolfgang.weinmann@irm.unibe.ch

Michal Bechny, Dr.

CONTACT

+41 76 221 62 56; mbechny@ethz.ch

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 22, 2026
• First Posted: February 10, 2026
• Study Start: January 5, 2026
• Primary Completion (Estimated): June 19, 2026
• Study Completion (Estimated): June 19, 2026
• Last Updated: February 10, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

CH (1)