AzTrials
AzTrials

Marijuana DependencePhase 3V-PAXNCT02955329

Vaping THC From Electronic Cigarettes

A Phase 3 study testing Nicotine, Cannabis and PAX Loose Leaf Vaporizer in people with Marijuana Dependence, run by University of California, San Francisco at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

This study aims to understand THC pharmacology and the safety of cannabis vaping, including the pharmacology and safety of co-administration of nicotine and THC. The study is designed as a within-subjects single-blinded crossover study. Read more about this study

Who is it for?
Ages 21 to 70 yearsHealthy volunteers can take part
Conditions the study is for
Marijuana Dependence
What is being tested?
Nicotine, Cannabis and PAX Loose Leaf Vaporizer
Type of treatment
Medical device
Could I receive a placebo?
No, everyone receives an active treatment
How many people
8 participants
Where
1 siteUnited States
Study dates
20 Mar 2019to 30 Nov 2019
Phase
Phase 3
Are there results?
Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 21 to 70 years
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • Age >=21 years <=70 years
  • Regular user of tobacco cigarettes (daily or most days)
  • Regular user of cannabis in any form (combusted or ingested) at least 5 days out of the month.
  • Positive for Tetrahydrocannabinol (THC) on screening toxicology test
  • Willing to abstain from tobacco smoking and all other combustible products (ex: cigars) for 12 hours prior to each outpatient hospital admission.
  • Willing to abstain from smoking/ingesting cannabis for 12 hours prior to each outpatient hospital admission.
Show all 13Show fewer
  • Willing to abstain from using any kind of nicotine products for 12 hours prior to each outpatient hospital admission (ex: electronic cigarettes, nicotine replacement therapy).
  • Saliva cotinine ≥ 30 ng/mL and/or NicAlert of 6
  • Healthy (based on limited physical examination and medical history collected during screening)
  • Heart rate < 105 beats per minute (BPM)
  • Systolic Blood Pressure < 160 and > 90 (considered out of range if both machine and manual readings are above/below these thresholds)
  • Diastolic Blood Pressure < 100 and > 50 (considered out of range if both machine and manual readings are above/below these thresholds)
  • Body Mass Index ≤<=38.0

Who cannot join

  • Medical (The following unstable medical conditions):
  • Heart disease
  • Uncontrolled hypertension
  • Thyroid disease (okay if controlled with medication)
  • Diabetes
  • Hepatitis B or C or Liver disease
Show all 40Show fewer
  • Glaucoma
  • Prostatic hypertrophy
  • History of paranoia after marijuana use
  • Psychiatric conditions
  • Current or past schizophrenia, and/or current or past bipolar disorder
  • Adult onset Attention-deficit/hyperactivity disorder (ADHD) (if being treated)
  • 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
  • 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 and are currently abstaining from drug and alcohol
  • Positive toxicology test at the screening visit (THC \& prescribed medications okay)
  • Methadone replacement therapy
  • Scoring a 2 or higher on the Severity of Dependence Scale for cannabis use.
  • Psychiatric medications
  • Current regular use of any psychiatric medications with the exception of Selective Serotonin Reuptake Inhibitors (SSRIs) and serotonin-norepinephrine reuptake Inhibitors (SNRIs) and current evaluation by the study physician that the participant is otherwise healthy, stable, and able to participate.
  • Other 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
  • Other/Misc. Chronic Health Conditions
  • Oral thrush
  • Fainting
  • Untreated thyroid disease
  • Other "life threatening illnesses" as per study physician's discretion
  • Use of Other Tobacco Products (OTP); any of the following products in combination more than 15 times in the past month
  • smokeless tobacco
  • pipes
  • cigars, cigarillos
  • blunts, spliffs
  • Pregnancy
  • Pregnancy (self-reported and urine pregnancy test)
  • Breastfeeding (determined by self-report)
  • Concurrent participation in another clinical trial
  • Inability to communicate in English
  • Planning to quit smoking or cannabis use within the next 60 days

Trial locations and contacts

1 site in 1 country.

United States1 site

  • Zuckerberg San Francisco General Hospital

    San Francisco, California, 94110

Other trials in United States

About this study

Official title: Vaping THC From Electronic Cigarettes: a Novel Evaluation of Intake and Pharmacokinetics

This study aims to understand THC pharmacology and the safety of cannabis vaping, including the pharmacology and safety of co-administration of nicotine and THC. The study is designed as a within-subjects single-blinded crossover study. Fourteen smokers of tobacco cigarettes and cannabis will switch between three conditions, namely: (a) vaping cannabis leaf, (b) vaping tobacco containing nicotine and (c) vaping a combination of cannabis leaf and tobacco containing nicotine. All participants will vape each product with the PAX loose-leaf vaporizer. The study will be conducted during three outpatient visits separated by at least 48 hours. The order of treatment (cannabis leaf, tobacco with nicotine, cannabis leaf \& tobacco with nicotine) will be counterbalanced between subjects. Subjects will be blinded to the content of the vaporizer on the study day but will be told during screening that they will vape cannabis alone, tobacco alone, and cannabis plus tobacco with nicotine.

Read the detailed description

Electronic cigarettes (e-cigarettes) have proliferated at a rapid rate since their introduction into the US market in 2007, and their use as a form of nicotine delivery far outpaced the science base. Although the design of these devices continues to evolve, we have previously described nicotine intake, systemic retention, pharmacokinetics, and vaping behavior associated with self-administration of e-cigarettes. We demonstrated that while the shape of the plasma nicotine concentration-time curve for e-cigarettes is similar to tobacco cigarettes, the maximum plasma nicotine concentration is, on average, lower for e-cigarettes. During ad libitum access, e-cigarettes were vaped intermittently in groups of 2-5 puffs or single puffs such that plasma nicotine levels rose gradually and peaked at the end of the 90-minute session. This differs from the rapid increase in plasma nicotine observed during controlled use of e-cigarettes or during tobacco cigarette smoking. Taken together, these results indicate that e-cigarettes have the potential to produce and sustain nicotine addiction but their use and abuse liability may differ from tobacco cigarettes.

The study is designed as a within-subjects, single-blinded crossover study. Fourteen smokers of tobacco cigarettes and cannabis will switch between three conditions, namely: (a) vaping cannabis leaf, (b) vaping tobacco containing nicotine and (c) vaping a combination of cannabis leaf and tobacco containing nicotine. All participants will vape each product with the PAX loose-leaf vaporizer, which will be purchased by the study team. The cannabis leaf will be obtained through the National Institute on Drug Abuse Drug Supply Program. The tobacco-containing nicotine, used in conditions (b) and (c) will come from commercially available Marlboro brand cigarettes. The same amount of cannabis or tobacco will be used in all conditions.

The study will be conducted during three outpatient visits separated by at least 48 hours. The order of treatment (cannabis leaf, tobacco with nicotine, cannabis leaf \& tobacco with nicotine) will be counterbalanced between subjects. Subjects will be blinded to the content of the vaporizer on the study day but will be told during screening that they will vape cannabis alone, tobacco alone, and cannabis plus tobacco with nicotine.

While scientists struggle to keep up with the latest electronic cigarette trends, the use of these devices for cannabis rather than nicotine is increasingly prevalent. Electronic cigarette use is not restricted to nicotine. Marijuana, the most widely used illicit drug has traditionally been combusted but the vaping of loose-leaf marijuana and THC oil has been increasing. the latest national data show that 7.6% of current marijuana users (past 30 days) and 9.9% of ever cannabis users (lifetime) administered THC through a vaporizer or electronic device (the study did not differentiate between vaporizers and electronic devices like e-cigarettes). The prevalence of vaped marijuana or THC is higher among younger adults. Prevalence of vaped marijuana/THC among 18-24 and 25-34 year-old ever marijuana users was 19.3% and 16.3%, respectively, compared to 8.8% for 35-49 year-olds and 5.7% for those 50 years and over. A recent study also showed high rates of cannabis vaping among high school students (18.0% among ever e-cigarette users). Smoking of a combination of tobacco and marijuana in cigarette form is also common, particularly in Europe. However, very little is known about the safety and pharmacokinetics of this co-administration making it a critical area of research.

Being tested
Nicotine, Cannabis, PAX Loose Leaf Vaporizer
Keywords
THC, Tobacco, Vaping
Medical subject headings
Marijuana Abuse, Vaping

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • NicotineDrug

    Also called Tobacco Leaf

    Participants will vape tobacco leaves with nicotine out of the PAX device.

  • CannabisDrug

    Also called Marijuana Leaf

    Participants will vape marijuana leaves with nicotine out of the PAX device.

  • PAX Loose Leaf VaporizerDevice

    In all three arms, the participant will be using the same PAX electronic cigarette device. The only difference is whether the participant will be vaping nicotine only, THC only, or nicotine and THC.

Study groups in NCT02955329
Study groupRoleWhat they receive
Tobacco ArmExperimentalParticipants will vape tobacco leaves with nicotine out of the PAX device.
Receives: Drug: Nicotine; Device: PAX Loose Leaf Vaporizer
Cannabis ArmExperimentalParticipants will vape marijuana leaves with THC (Tetrahydrocannabinol) out of the PAX device.
Receives: Drug: Cannabis; Device: PAX Loose Leaf Vaporizer
Combined Cannabis and Tobacco ArmExperimentalParticipants will vape flavorless 6% nicotine e-liquid, followed by THC (Tetrahydrocannabinol) out of the PAX device.
Receives: Drug: Nicotine; Drug: Cannabis; Device: PAX Loose Leaf Vaporizer

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Mean Delivered and Retained Doses

    Delivered Tetrahydrocannabinol (THC) and nicotine doses are estimated as the change in e-cigarette weight × concentration of THC or nicotine in e-liquid. The amount of THC or nicotine systemically retained is estimated as delivered dose minus amount in gas traps.

    Measured: Study Day 1-3

  2. Median Peak THC Concentration (Cmax)

    Median peak concentration of THC between vaped loose-leaf cannabis, mixture of cannabis and tobacco containing nicotine, and the tobacco alone treatment condition will be reported

    Measured: Study Day 1-3

  3. Median Peak Nicotine Concentration (Cmax)

    Median peak concentration of nicotine between vaped loose-leaf cannabis, mixture of cannabis and tobacco containing nicotine, and the tobacco alone treatment condition will be reported

    Measured: Study Day 1-3

  4. Median THC Exposure

    Median exposure of nicotine using area under the blood/plasma concentration-time curve(AUC) between vaped loose-leaf cannabis, mixture of cannabis and tobacco containing nicotine, and the tobacco alone treatment condition will be reported

    Measured: Study Day 1-3

  5. Median Nicotine Exposure

    Compare median exposure of nicotine using AUC (area under the blood/plasma concentration-time curve) between vaped loose-leaf tobacco containing nicotine vs. mixture of cannabis and tobacco containing nicotine.

    Measured: Study Day 1-3

  6. Mean Heart Rate

    Heart rate monitoring by pulse oximeter

    Measured: Study Day 1-3

  7. Mean Score on the Drug Effects Questionnaire (DEQ)

    The Drug Effects Questionnaire (DEQ) is widely used in studies of acute subjective response (SR) to a variety of substances which assessed the extent to which participants (1) feel any substance effect(s), (2) feel high, (3) like the effects, (4) dislike the effects, and (5) want more of the substance by instructing participants to place a mark on a 100mm vertical, visual, analog scale with scores ranging from 0 ="not at all" to 100 = "extremely" for each question. The mean of the individual responses is used to general a total score with a range from 0 to 100, with higher scores indicate a greater "liking" of the effects of the substance. The mean and standard deviation of each treatment condition will be reported.

    Measured: Study Day 1-3

  8. Mean Scores on the Marijuana Craving Questionnaire-Short Form (MCQ-SF)

    This 12-item multidimensional measure assesses cannabis craving based on 4 factors: Compulsivity, Emotionality, Expectancy, Purposefulness. Each item asks about the respondent's feelings and thoughts about smoking marijuana as he or she is completing the questionnaire (i.e., right now). Each response is scored a number ranging from 1 (strongly disagree) to 7 (strongly agree) with higher scores indicating a greater level of craving. The calculation of each subscale is as follows: Compulsivity: Mean of items 2, 7, and 10; Emotionality: Mean of items 4, 6, and 9; Expectancy: Mean of items 5, 11, and 12; Purposefulness: Mean of items 1, 3, and 8 with the minimum possible score = 1 and the maximum possible score = 7 for any subscale. The mean and standard deviation of each subscale for each treatment condition will be reported.

    Measured: Study Day 1-3

  9. Mean Scores on the Modified Cigarette Evaluation Questionnaire (mCEQ)

    The modified Cigarette Evaluation Questionnaire (mCEQ) uses three multi-item subscales and two single items: "Smoking Satisfaction" (items 1, 2, and 12);"Psychological Reward" (items 4 through 8); "Aversion" (items 9 and 10);"Enjoyment of Respiratory Tract Sensations" (item 3); and "Craving Reduction"(item 11). Scores for each subscale are calculated as the mean of the individual item responses or the single item. Higher scores indicate greater intensity on that scale. Items are rated on a seven-point scale ranging from 1 (not at all) to 7 (extremely) and total scores are averaged across all items with a minimum average score of 1 and a maximum average score of 7. Higher scores indicate greater intensity of each smoking effect with, for example, greater satisfaction or psychological reward after smoking. The mean and standard deviation for each treatment condition will be reported.

    Measured: Study Day 1-3

  10. Mean Scores on the Positive Affect Negative Affect Schedule (PANAS)

    The Positive and Negative Affect Schedule (PANAS) is a brief scale is comprised of 20 items, with 10 items measuring positive affect (e.g., excited, inspired) and 10 items measuring negative affect (e.g., upset, afraid). Each item is rated on a five-point Likert Scale, ranging from 1 = Very Slightly or Not at all to 5 = Extremely, to measure the extent to which the affect has been experienced in a specified time frame and the final score is derived out of the sum of the ten items on both the positive and negative side. Scores can range from 10-50 for both the Positive and Negative Affect with the lower scores representing lower levels of Positive/Negative Affect and higher scores representing higher levels of Positive/Negative Affect.

    Measured: Study Day 1-3

  11. Mean Scores on the Minnesota Nicotine Withdrawal Scale (MNWS)

    The Minnesota Nicotine Withdrawal Scale is an 7-item self - report scale designed to measure the severity of craving and withdrawal symptoms experienced during smoking cessation. Each item is rated on a scale of 0 to 4 with 0=none,1= Slight, 2= Mild, 3= Moderate, and 4=Severe. Seven of the items are symptoms derived from the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) Tobacco Withdrawal diagnosis and are as follows: depression, insomnia, irritability/frustration/anger, anxiety/nervousness, difficulty concentrating, restlessness, increased appetite and at least five of seven items must have responses in order to generate a reliable score. The responses to each item are summed to produce a total withdrawal summary score with greater scores indicating a higher level of severity in nicotine withdrawal symptoms overall. The mean and standard deviation of each treatment condition will be reported with a minimum mean score of 0 and a maximum mean score of 4.

    Measured: Study Day 1-3

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted4 Nov 2016 (estimated)
  2. Study start20 Mar 2019
  3. Primary completion30 Nov 2019
  4. Study completion30 Nov 2019

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 3
Primary purpose
Other
Allocation
Randomised
Intervention model
Crossover
Masking
Single blind
Who is masked
Participant
Enrolment
8 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT02955329
Sponsor's protocol ID
18-24854
Other IDs
3R01DA039264-02S1
Acronym
V-PAX
Status last verified
Jun 2023
First submitted
31 Oct 2016
Last updated
29 Jun 2023
Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
Yes
Individual data sharing
No

Publications

  • King BA, Patel R, Nguyen KH, Dube SR. Trends in awareness and use of electronic cigarettes among US adults, 2010-2013. Nicotine Tob Res. 2015 Feb;17(2):219-27. doi: 10.1093/ntr/ntu191. Epub 2014 Sep 19.

    PubMed 25239961

  • Arrazola RA, Singh T, Corey CG, Husten CG, Neff LJ, Apelberg BJ, Bunnell RE, Choiniere CJ, King BA, Cox S, McAfee T, Caraballo RS; Centers for Disease Control and Prevention (CDC). Tobacco use among middle and high school students - United States, 2011-2014. MMWR Morb Mortal Wkly Rep. 2015 Apr 17;64(14):381-5.

    PubMed 25879896

  • St Helen G, Havel C, Dempsey DA, Jacob P 3rd, Benowitz NL. Nicotine delivery, retention and pharmacokinetics from various electronic cigarettes. Addiction. 2016 Mar;111(3):535-44. doi: 10.1111/add.13183. Epub 2015 Nov 11.

    PubMed 26430813

  • St Helen G, Ross KC, Dempsey DA, Havel CM, Jacob P 3rd, Benowitz NL. Nicotine Delivery and Vaping Behavior During ad Libitum E-cigarette Access. Tob Regul Sci. 2016 Oct;2(4):363-376. doi: 10.18001/TRS.2.4.8.

    PubMed 28393086

  • Center for Behavioral Health Statistics and Quality. Behavioral health trends in the United States: Results from the 2014 National Survey on Drug Use and Health. NSDUH; 2015.

  • Schauer GL, King BA, Bunnell RE, Promoff G, McAfee TA. Toking, Vaping, and Eating for Health or Fun: Marijuana Use Patterns in Adults, U.S., 2014. Am J Prev Med. 2016 Jan;50(1):1-8. doi: 10.1016/j.amepre.2015.05.027. Epub 2015 Aug 12.

    PubMed 26277652

  • Morean ME, Kong G, Camenga DR, Cavallo DA, Krishnan-Sarin S. High School Students' Use of Electronic Cigarettes to Vaporize Cannabis. Pediatrics. 2015 Oct;136(4):611-6. doi: 10.1542/peds.2015-1727. Epub 2015 Sep 7.

    PubMed 26347431

  • Akre C, Michaud PA, Berchtold A, Suris JC. Cannabis and tobacco use: where are the boundaries? A qualitative study on cannabis consumption modes among adolescents. Health Educ Res. 2010 Feb;25(1):74-82. doi: 10.1093/her/cyp027. Epub 2009 Jun 10.

    PubMed 19515745

  • Amos A, Wiltshire S, Bostock Y, Haw S, McNeill A. 'You can't go without a fag...you need it for your hash'--a qualitative exploration of smoking, cannabis and young people. Addiction. 2004 Jan;99(1):77-81. doi: 10.1111/j.1360-0443.2004.00531.x.

    PubMed 14678065

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Nicotine, Cannabis and PAX Loose Leaf Vaporizer in people with Marijuana Dependence, run by University of California, San Francisco at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 13 inclusion and 40 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 29 Jun 2023. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 30 Apr 2021). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Mean Delivered and Retained Doses (time frame: Study Day 1-3). The study lists 11 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT02955329, which also lists 9 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jun 2023.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Keep searching with a free account

You’ve used your 3 free searches for this session. Log in or create a free AzTrials account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in