Understanding the Clinical Pharmacology of Marijuana-Tobacco Co-administration
CANNIC
2 other identifiers
interventional
48
1 country
1
Brief Summary
This is a crossover, randomized, double-blinded clinical pharmacology study enrolling dual cannabis-tobacco smokers to better understand the combined effects of co-administering cannabis and tobacco. The project aims to describe the pharmacokinetics and pharmacodynamics of marijuana-tobacco co-administration by delivering THC and nicotine in various combinations. This foundational study will establish a research program focused on elucidating the public health consequences of marijuana-tobacco co-use.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for phase_2
Started Jul 2025
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
August 11, 2023
CompletedFirst Posted
Study publicly available on registry
August 21, 2023
CompletedStudy Start
First participant enrolled
July 1, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
February 1, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
February 1, 2028
January 7, 2026
January 1, 2026
2.6 years
August 11, 2023
January 5, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (16)
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Baseline to Day 1
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 1 to Day 2
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 2 to Day 3
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 3 to Day 4
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 4 to Day 5
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 5 to Day 6
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 6 to Day 7
Change in peak plasma concentration of THC
To assess the differences between THC dosages, the study investigators will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.
From Day 7 to Day 8
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Baseline to Day 1
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 1 to Day 2
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 2 to Day 3
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 3 to Day 4
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 4 to Day 5
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 5 to Day 6
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 6 to Day 7
Change in Peak plasma concentration of nicotine
To assess the differences between nicotine dosages, the study investigators will determine maximum plasma nicotine concentration (Cmax) using plasma nicotine concentrations from the standardized sessions.
From Day 7 to Day 8
Secondary Outcomes (24)
Cardiovascular effects among dosages using heart rate as a measure
From Baseline to Day 1
Cardiovascular effects among dosages using heart rate as a measure
From Day 1 to Day 2
Cardiovascular effects among dosages using heart rate as a measure
From Day 2 to Day 3
Cardiovascular effects among dosages using heart rate as a measure
From Day 3 to Day 4
Cardiovascular effects among dosages using heart rate as a measure
From Day 4 to Day 5
- +19 more secondary outcomes
Study Arms (8)
Placebo marijuana and regular cigarette
EXPERIMENTALParticipants will vape a 50/50 mixture of placebo marijuana (0% THC) and regular cigarette (25.94 mg/g nicotine content)
Placebo marijuana and Very Low Nicotine Content cigarette
EXPERIMENTALParticipants will vape a 50/50 mixture of placebo marijuana (0% THC) and Very Low Nicotine Content cigarette (0.42 mg/g nicotine content)
Medium marijuana and regular cigarette
EXPERIMENTALParticipants will vape a 50/50 mixture of medium marijuana (\<5% THC) and regular cigarette (25.94 mg/g nicotine content)
Medium marijuana and Very Low Nicotine Content cigarette
EXPERIMENTALParticipants will vape a 50/50 mixture of medium marijuana (\<5% THC) and Very Low Nicotine Content cigarette (0.42 mg/g nicotine content)
High marijuana and regular cigarette
EXPERIMENTALParticipants will vape a 50/50 mixture of high marijuana (\>10% THC) and regular cigarette (25.94 mg/g nicotine content)
High marijuana and Very Low Nicotine Content cigarette
EXPERIMENTALParticipants will vape a 50/50 mixture of high marijuana (\>10% THC) and Very Low Nicotine Content cigarette (0.42 mg/g nicotine content)
High marijuana only
EXPERIMENTALParticipants will vape high marijuana (\>10% THC)
Regular cigarette only
EXPERIMENTALParticipants will vape a regular cigarette (25.94 mg/g nicotine content)
Interventions
Participants will vape marijuana in varying doses from the PAX device
Participants will vape Regular and Very Low Nicotine content cigarettes from the PAX device
In all arms, participants will be using the PAX Loose Leave Vaporizer.
Participants will vape placebo marijuana from the PAX device
Eligibility Criteria
You may qualify if:
- Heart rate \< 105 beats per minute (BPM)\*
- Systolic Blood Pressure \< 160 and \> 90\*
- Diastolic Blood Pressure \< 100 and \> 50\*
- \*Considered out of range if both machine and manual readings are above/below these thresholds.
- Body Mass Index (BMI) ≤ 38.0 (at investigator's discretion for higher BMI if no other concurrent health issues)
- Current regular user of cannabis who smokes or vapes cannabis or THC extracts at least three days a week for the past 3 months or more
- Test positive for D-9-tetrahydrocannabinol (THC) at screening and self-report of cannabis use
- Current user of inhaled forms of tobacco/nicotine (cigarette, cigars, e-cigarettes) who use the product daily for the past 3 months or more
- Saliva cotinine ≥ 30 ng/mL
You may not qualify if:
- Unstable medical conditions:
- Heart disease
- Seizures
- Cancer
- Thyroid disease (okay if controlled with medication)
- Diabetes
- Hepatitis B or C or Liver disease
- Glaucoma
- Kidney disease or urinary retention
- An ulcer in the past year
- Active use of an inhaler for asthma or Chronic Obstructive Pulmonary Disease (COPD)
- Hypertension if uncontrolled (meaning participant has a diagnosis, but they are not taking medication/under treatment (e.g., diet or exercise plan)
- Drug/Alcohol Dependence
- Alcohol or illicit drug dependence within the past 12 months (currently in treatment) with the exception of those who recently completed an alcohol/drug treatment program
- Positive toxicology test at the screening visit (THC \& prescribed medications okay)
- +31 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- University of California, San Franciscolead
- National Institute on Drug Abuse (NIDA)collaborator
- National Institutes of Health (NIH)collaborator
- Food and Drug Administration (FDA)collaborator
Study Sites (1)
Zuckerberg San Francisco General Hospital
San Francisco, California, 94110, United States
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Gideon St Helen
University of California, San Francisco
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- BASIC SCIENCE
- Intervention Model
- CROSSOVER
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
August 11, 2023
First Posted
August 21, 2023
Study Start
July 1, 2025
Primary Completion (Estimated)
February 1, 2028
Study Completion (Estimated)
February 1, 2028
Last Updated
January 7, 2026
Record last verified: 2026-01
Data Sharing
- IPD Sharing
- Will not share