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THC Crossover Study (TRDRP)

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ClinicalTrials.gov Identifier: NCT04429568
Recruitment Status : Recruiting
First Posted : June 12, 2020
Last Update Posted : July 16, 2021
Sponsor:
Collaborator:
Tobacco Related Disease Research Program
Information provided by (Responsible Party):
University of California, San Francisco

Brief Summary:
This is a randomized, crossover study enrolling experienced dual cannabis-tobacco smokers (N=18) to describe the differences in THC and toxicant exposure, examining pharmacokinetic, subjective, and cardiovascular effects from smoking and vaping dry herb cannabis. This study will also examine the differences in toxicant exposure and cardiovascular disease risk between smoking cannabis and smoking tobacco cigarettes.

Condition or disease Intervention/treatment Phase
THC Cannabis Cannabis Smoking Cannabis Use, Unspecified Cigarette Smoking Tobacco Use Nicotine Dependence Nicotine Withdrawal Cardiovascular Risk Factor Other: Smoked Cannabis Other: Vaped Cannabis Other: Tobacco Cigarette Not Applicable

Detailed Description:
Experienced dual cannabis-tobacco smokers will participate in a within-subject crossover study with three blocks: smoked cannabis (purchased by participants from a local dispensary), dry herb cannabis vaporizer, and usual brand tobacco cigarette. Each block will consist of 2 consecutive days on an inpatient research ward. The first inpatient day of each block will comprise of two sessions: (1) The first session will be a standardized bout to compare pharmacokinetic, physiologic, and subjective effects of cannabis and tobacco use; (2) after 6 hours of abstinence, the second session will be ad libitum access to the assigned product for 2 hours to compare subjective effects (reward, satisfaction, craving reduction) and use patterns. The second inpatient day will consist of ad libitum use of the assigned product from 8:00 in the morning to midnight. An abstinence day will be added after the second day of the last block to assess exposure and effects biomarkers during a period of abstinence from cannabis (smoked/vaped) or tobacco.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 18 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Cardiovascular Effects of Cannabis Compared to Tobacco Use
Actual Study Start Date : October 30, 2020
Estimated Primary Completion Date : June 30, 2022
Estimated Study Completion Date : June 30, 2022

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Marijuana

Arm Intervention/treatment
Smoked Cannabis, Vaped Cannabis, or Tobacco Cigarette
  • Abstinence from any product night before hospital admission
  • Standardized Session of assigned product: smoked cannabis, vaped cannabis, or tobacco cigarette
  • 6-hr abstinence and blood draws (PK)
  • 2 hr Free use session w/ video monitoring
  • Free use of assigned product
  • 12-hr cardiovascular (CV) monitoring
  • Circadian blood draws
  • 12-hr urine collection
Other: Smoked Cannabis
Cannabis will be purchased by the participants and reimbursed the full cost by the study. Participants will be asked to purchase enough to last 2 full days of use. To reduce variability between products, participants will be asked to purchase cannabis from one dispensary near the research facility (Purple Star MD at 2520 Mission St., San Francisco). Receipt must be provided to study staff.

Other: Vaped Cannabis
Cannabis will be purchased by the participants and reimbursed the full cost by the study. Participants will be asked to purchase enough to last 2 full days of use. To reduce variability between products, participants will be asked to purchase cannabis from one dispensary near the research facility (Purple Star MD at 2520 Mission St., San Francisco). Receipt must be provided to study staff. All participants will use the study-provided PAX® (PAX 2) dry herb vaporizer, one of the most popular handheld vaporizers.

Other: Tobacco Cigarette
Tobacco cigarettes of participants' choice (usual brand) will be provided by research staff for use on the study.

Either of the 2 remaining products
  • Abstinence from any product night before hospital admission
  • Standardized Session of assigned product: smoked cannabis, vaped cannabis, or tobacco cigarette
  • 6-hr abstinence and blood draws (PK)
  • 2 hr Free use session w/ video monitoring
  • Free use of assigned product
  • 12-hr CV monitoring
  • Circadian blood draws
  • 12-hr urine collection
Other: Smoked Cannabis
Cannabis will be purchased by the participants and reimbursed the full cost by the study. Participants will be asked to purchase enough to last 2 full days of use. To reduce variability between products, participants will be asked to purchase cannabis from one dispensary near the research facility (Purple Star MD at 2520 Mission St., San Francisco). Receipt must be provided to study staff.

Other: Vaped Cannabis
Cannabis will be purchased by the participants and reimbursed the full cost by the study. Participants will be asked to purchase enough to last 2 full days of use. To reduce variability between products, participants will be asked to purchase cannabis from one dispensary near the research facility (Purple Star MD at 2520 Mission St., San Francisco). Receipt must be provided to study staff. All participants will use the study-provided PAX® (PAX 2) dry herb vaporizer, one of the most popular handheld vaporizers.

Other: Tobacco Cigarette
Tobacco cigarettes of participants' choice (usual brand) will be provided by research staff for use on the study.

Remaining product
  • Abstinence from any product night before hospital admission
  • Standardized Session of assigned product: smoked cannabis, vaped cannabis, or tobacco cigarette
  • 6-hr abstinence and blood draws (PK)
  • 2 hr Free use session w/ video monitoring
  • Free use of assigned product
  • 12-hr CV monitoring
  • Circadian blood draws
  • 12-hr urine collection
Other: Smoked Cannabis
Cannabis will be purchased by the participants and reimbursed the full cost by the study. Participants will be asked to purchase enough to last 2 full days of use. To reduce variability between products, participants will be asked to purchase cannabis from one dispensary near the research facility (Purple Star MD at 2520 Mission St., San Francisco). Receipt must be provided to study staff.

Other: Vaped Cannabis
Cannabis will be purchased by the participants and reimbursed the full cost by the study. Participants will be asked to purchase enough to last 2 full days of use. To reduce variability between products, participants will be asked to purchase cannabis from one dispensary near the research facility (Purple Star MD at 2520 Mission St., San Francisco). Receipt must be provided to study staff. All participants will use the study-provided PAX® (PAX 2) dry herb vaporizer, one of the most popular handheld vaporizers.

Other: Tobacco Cigarette
Tobacco cigarettes of participants' choice (usual brand) will be provided by research staff for use on the study.




Primary Outcome Measures :
  1. Peak plasma concentration [ Time Frame: Day 1 of each arm ]
    To assess the differences between smoked and vaped cannabis, we will determine maximum plasma THC concentration (Cmax) using plasma THC concentrations from the standardized sessions.

  2. Time to peak plasma concentration [ Time Frame: Day 1 of each arm ]
    To assess the differences of these variables between smoked and vaped cannabis, we will determine the time to max concentration (Tmax) using plasma THC concentrations from the standardized sessions.

  3. Area under the plasma concentration versus time curve (AUC) [ Time Frame: Day 1 of each arm ]
    To assess the differences of these variables between smoked and vaped cannabis, we will determine the AUC using plasma THC concentrations from the standardized sessions.

  4. Subjective effects between cannabis products using the Marijuana Cravings Questionnaire [ Time Frame: Days 1-2 of each arm ]
    We will assess measures from the Marijuana Cravings Questionnaire (MCQ) and compare them between smoked and vaped cannabis.

  5. Subjective effects between cannabis products using the Visual Analog Scale [ Time Frame: Days 1-2 of each arm ]
    We will assess measures from the Visual Analog Scale (VAS) and compare them between smoked and vaped cannabis.

  6. Subjective effects between cannabis products using the Drug Effects Questionnaire [ Time Frame: Days 1-2 of each arm ]
    We will assess measures from the Drug Effects Questionnaire (DEQ) and compare them between smoked and vaped cannabis.

  7. Max change of expired carbon monoxide [ Time Frame: Days 1-2 of the cannabis arms ]
    We will examine differences in max change of expired carbon monoxide (CO) from day 1 between smoked and vaped cannabis.

  8. Area under the expired carbon monoxide (CO) curve (AUC) [ Time Frame: Days 1-2 of the cannabis arms ]
    We will examine differences in integrated AUC of expired carbon monoxide from day 1 between smoked and vaped cannabis.

  9. Differences in metabolites of volatile organic compounds (VOCs) [ Time Frame: Days 1-2 of the cannabis arms ]
    We will examine differences in 12-hour urine mercapturic acid metabolites of volatile organic compounds (from day 2) between smoked and vaped cannabis.

  10. Exposure to toxicants between cannabis products [ Time Frame: Days 1-2 of the cannabis arms ]
    We will also examine how measures of use (number of puss, amount use, number of use episodes) correlate with biomarker concentrations between smoked and vaped cannabis.

  11. Cardiovascular effects between cannabis products using heart rate as a measure [ Time Frame: Day 1 of each arm ]
    We will compare maximum change in heart rate as well as an integrated measure of heart rate over the first 30 minutes after the standardized session (day 1) between smoked and vaped cannabis.

  12. Cardiovascular effects between cannabis products using epinephrine as a measure [ Time Frame: Day 2 of each cannabis arm ]
    Urine catecholamine excretion, particularly epinephrine, will be examined in 12-hour urines and compared between smoked and vaped cannabis.

  13. Cardiovascular effects between cannabis products using platelet activation as a measure [ Time Frame: Day 2 of each cannabis arm ]
    We will examine differences in blood and urine biomarkers of platelet activation between smoked and vaped cannabis.

  14. Cardiovascular effects between cannabis products using oxidant stress as a measure [ Time Frame: Day 2 of each cannabis arm ]
    We will examine differences in blood and urine biomarkers of oxidant stress between smoked and vaped cannabis.

  15. Cardiovascular effects between cannabis products using endothelial dysfunction as a measure [ Time Frame: Day 2 of each cannabis arm ]
    We will examine differences in blood and urine biomarkers of endothelial dysfunction and inflammation between smoked and vaped cannabis.


Secondary Outcome Measures :
  1. Toxicant exposure between smoked tobacco and cannabis using expired carbon monoxide as the measure [ Time Frame: Day 1 of each arm ]
    We will examine differences in expired carbon monoxide (CO) from day 1 (both max change and integrated AUC of expired CO) between smoked tobacco and cannabis.

  2. Toxicant exposure between smoked tobacco and cannabis using mercapturic acid as the measure [ Time Frame: Day 2 of each arm ]
    We will examine differences in 12-hour urine mercapturic acid metabolites of volatile organic compounds (VOCs) (from day 2) between smoked tobacco and cannabis.

  3. Toxicant exposure between smoked tobacco and cannabis using use as a measure [ Time Frame: Days 1-2 of each arm ]
    We will also examine how measures of use (number of puffs, amount use, number of use episodes) correlate with biomarker concentrations between smoked tobacco and cannabis.

  4. Cardiovascular effects between smoked tobacco and cannabis using heart rate as a measure [ Time Frame: Day 1 of each arm ]
    We will compare maximum change in heart rate as well as an integrated measure of heart rate over the first 30 minutes after the standardized session (day 1) between smoked tobacco and cannabis.

  5. Cardiovascular effects between smoked tobacco and cannabis using epinephrine as a measure [ Time Frame: Day 2 of each arm ]
    Urine catecholamine excretion, particularly epinephrine, will be examined in 12-hour urines.

  6. Cardiovascular effects between smoked tobacco and cannabis using platelet activation as a measure [ Time Frame: Day 2 of each arm ]
    We will examine differences in blood and urine biomarkers of platelet activation between smoked tobacco and cannabis.

  7. Cardiovascular effects between smoked tobacco and cannabis using oxidant stress as a measure [ Time Frame: Day 2 of each arm ]
    We will examine differences in blood and urine biomarkers of oxidant stress between smoked tobacco and cannabis.

  8. Cardiovascular effects between smoked tobacco and cannabis using endothelial dysfunction as a measure [ Time Frame: Day 2 of each arm ]
    We will examine differences in blood and urine biomarkers of endothelial dysfunction and inflammation between smoked tobacco and cannabis.

  9. Puffing behaviors across all products [ Time Frame: Days 1-2 of each arm ]
    We will examine how puffing behaviors are different between all products (smoked and vaped cannabis, as well as with smoked tobacco cigarettes) and how they correlate with toxicant biomarker concentrations. Vaping topography measures will be obtained from frame by frame analysis of high definition videos.



Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


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Ages Eligible for Study:   21 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Healthy on the basis of medical history and limited physical examination, as described below:

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.

  • Current regular user of cannabis who smokes cannabis as joint or blunt at least 3 times a week for past 3 months
  • History of cannabis vaporizer use or willingness to use the vaporizer in the study
  • Current tobacco cigarette use who smokes ≥ 5 cigarettes per day
  • Saliva cotinine ≥ 50 ng/ml
  • Test positive for D-9-tetrahydrocannabinol (THC) at screening and self-report of cannabis use

Exclusion Criteria:

  • Unstable medical conditions:

Heart disease; Uncontrolled hypertension; Thyroid disease (okay if controlled with medication); Diabetes; Hepatitis B or C or Liver disease; Glaucoma; Prostatic hypertrophy

  • Psychiatric conditions:

Current or past schizophrenia, and/or current or past bipolar disorder; Adult onset attention deficit hyperactivity disorder (ADHD); Participants with current or past depression and/or anxiety disorders will be reviewed by the study physician and considered for inclusion; History of psychiatric hospitalizations are not exclusionary, but study participation will be determined as per study physician's approval

  • Concurrent regular use of smokeless tobacco or pipes [occasional users of these products may be enrolled if they agree to abstain from their use during the period of the study]
  • Medications:

Use of medications that are inducers of nicotine metabolizing enzyme CYP2A6 (Example: rifampicin, dexamethasone, phenobarbital, and other anticonvulsant drugs).; Concurrent use of nicotine-containing medications; Psychiatric medications: current regular use of any psychiatric medications with the exception of Selective Serotonin Reuptake Inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI) and current evaluation by the study physician that the participant is otherwise healthy, stable, and able to participate.

  • Other/Misc. Chronic Health Conditions:

Oral thrush; Fainting; Untreated thyroid disease; Other "life threatening illnesses" as per study physician's discretion

  • Pregnancy:

Pregnancy (self-reported and urine pregnancy test); Breastfeeding (determined by self-report)

  • Drug/Alcohol Dependence:

Alcohol or illicit drug dependence within the past 12 months with the exception of those who have recently completed an alcohol/drug treatment program; Positive toxicology test at the screening visit (THC & prescribed medications okay); Methadone replacement therapy

  • Concurrent participation in another clinical trial
  • Inability to communicate in English
  • History of marijuana-induced psychosis or paranoia after smoking marijuana
  • Scoring a 2 or higher on the Severity of Dependence Scale for cannabis use
  • Planning to quit smoking or vaping within the next 60 days

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04429568


Contacts
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Contact: Sundos Yassin 628-206-8955 sundos.yassin@ucsf.edu
Contact: Armando Barraza 628-206-4361 armando.barraza@ucsf.edu

Locations
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United States, California
Zuckerberg San Francisco General Hospital Recruiting
San Francisco, California, United States, 94110
Contact: Bernadette Tobin         
University of California, San Francisco Recruiting
San Francisco, California, United States, 94143
Contact: Sundos Yassin    628-206-8955    sundos.yassin@ucsf.edu   
Contact: Armando Barraza    628-206-4361    armando.barraza@ucsf.edu   
Principal Investigator: Gideon St. Helen, PhD         
Sponsors and Collaborators
University of California, San Francisco
Tobacco Related Disease Research Program
Investigators
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Principal Investigator: Gideon St. Helen, PhD University of California, San Francisco
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Responsible Party: University of California, San Francisco
ClinicalTrials.gov Identifier: NCT04429568    
Other Study ID Numbers: 17-24117
First Posted: June 12, 2020    Key Record Dates
Last Update Posted: July 16, 2021
Last Verified: July 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by University of California, San Francisco:
vape
cannabis
tobacco cigarette
thc
marijuana
smoking
Additional relevant MeSH terms:
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Marijuana Abuse
Tobacco Use Disorder
Substance-Related Disorders
Chemically-Induced Disorders
Mental Disorders