Skip to content

Varenicline for Co-occurring Cannabis and Tobacco Use

Feasibility and Preliminary Effectiveness of Varenicline for Co-occurring Cannabis and Tobacco Use

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04595318
Enrollment
7
Registered
2020-10-20
Start date
2015-01-31
Completion date
2015-07-31
Last updated
2024-09-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cannabis Dependence, Tobacco Dependence

Brief summary

Pilot, eight week, open-label, within-subject cross over trial of four weeks of standard clinical care (SCC) in an outpatient substance use disorder treatment program and four weeks of SCC and varenicline among current and former tobacco smokers with frequent cannabis use.

Detailed description

Treating co-occurring cannabis and tobacco use disorders might reduce the health burdens associated with both substances. However, few studies have evaluated pharmacological interventions, in combination with behavioral treatment, to address co-occurring cannabis and tobacco use; these are limited by high participant attrition, poor adherence to interventions, and lack of control. Pilot, eight week, open-label, within-subject cross over trial of four weeks of standard clinical care (SCC) in an outpatient substance use disorder treatment program and four weeks of SCC and varenicline among current and former tobacco smokers with frequent cannabis use. Participants were recruited from an urban, outpatient substance use disorder treatment program that offers both intensive behavioral counseling and medications for opioid use disorder (MOUD). Participants were randomized to receive either SCC or SCC and varenicline first and then were crossed over to receive the opposite intervention. The study consisted of two 4-week treatment periods with no washout period. Outcomes are reported in pooled analyses of all participants in each treatment phase.

Interventions

DRUGStandard clinical care first, followed by standard clinical care and varenicline

Standard clinical care includes substance use disorder treatment program-based individual behavioral counseling at least once a month using motivational and cognitive behavioral strategies. Varenicline therapy includes a one month's supply of the medication in standard doses: 0.5 mg for 3 days, 0.5 mg twice a day for 4 days, then 1 mg twice a day for 21 days.

DRUGStandard clinical care and varenicline first, followed by standard clinical care

Standard clinical care includes substance use disorder treatment program-based individual behavioral counseling at least once a month using motivational and cognitive behavioral strategies. Varenicline therapy includes a one month's supply of the medication in standard doses: 0.5 mg for 3 days, 0.5 mg twice a day for 4 days, then 1 mg twice a day for 21 days.

Sponsors

National Institute on Drug Abuse (NIDA)
CollaboratorNIH
National Institute of General Medical Sciences (NIGMS)
CollaboratorNIH
Albert Einstein College of Medicine
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Able to speak English * Uses cannabis at least 5 days in the past 7 days * Current or former tobacco smoker * Has not taken varenicline in the past 30 days * Not pregnant, trying to conceive or breastfeeding * Able to provide informed consent * Test positive for cannabinoids by urine toxicology

Exclusion criteria

* Unstable medical or psychiatric illness * Opioid use disorder was initially exclusionary but eligibility criteria were revised after 32 individuals were screened to facilitate recruitment.

Design outcomes

Primary

MeasureTime frameDescription
Enrollment RateBaselinePercentage of the eleven eligible subjects willing to participate

Secondary

MeasureTime frameDescription
Overall Medication AdherenceUpon conclusion of SCC+Varenicline treatment (4 weeks or 8 weeks based on randomization to arm/group)Overall medication adherence was calculated as a percentage based on the number of pills prescribed during the study, corrected for the number of pills returned, divided by the period (in days), and multiplied by 100. An aggregate percentage of pills was calculated and reported for all seven study participants.
Number of Participants With Treatment-Emergent Adverse Events: Upset StomachUpon conclusion of SCC+VT treatment (4 weeks or 8 weeks based on randomization to arm/group)The number of participants with a self-reported adverse event of upset stomach was determined using a structured questionnaire of common varenicline symptoms
Number of Participants With Treatment-Emergent Symptoms of Major Depressive DisorderUpon conclusion of SCC+VT treatment (4 weeks or 8 weeks based on randomization to arm/group)The number of participants with self-reported Treatment-Emergent symptoms of major depressive disorder was determined using the MINI International Neuropsychiatric Interview (M.I.N.I), a short structured diagnostic interview tool used to assess DSM-IV and ICD-10 psychiatric disorders
Cannabis CravingWeek 4 and Week 8Cannabis craving was assessed using the Marijuana Craving Questionnaire-Short Form (MCQ-SF). The MCQ-SF is a valid and reliable, self-report instrument with 12 items rated on a 7-point Likert scale from 1 (strongly disagree) to 7 (strongly agree). The 12 items are grouped by certain characteristics and the score of each of resulting groups correlates to the intensity of the four craving dimensions (compulsivity, emotionality, expectancy, and purposefulness). Scores from the four subscales are summed with total possible scores ranging from 12 - 84. Higher scores are indicative of increased craving.
Cannabis WithdrawalWeek 4 and Week 8Cannabis withdrawal was measured by the 15-item version of the Marijuana Withdrawal Checklist (MWC). Participants rated each symptom experienced during their most recent period of marijuana abstinence, based on a 4-point scale where 0 = none, 1 = mild, 2 = moderate, and 3 = severe. A total MWC score was obtained by summing the responses. Possible total scoring ranges from 0 - 45, with 0 signifying no withdrawal symptoms and 45 signifying the most severe withdrawal symptoms.
Quantity of Cannabis UseWeek 4 and Week 8The quantity of cannabis use over the prior 14-day period was measured using the Timeline Follow-Back (TLFB) method. TLFS is a method in which participants used a physical calendar to quantify the number of days over a specified period of time (in this study 14 days) during which cannabis was used. An aggregate value for percentage of days of cannabis use was calculated by tabulating the total number of days cannabis was used by all study participants over the prior 14-day period and dividing by the total number of calendar days over this period across the 7 participants (i.e., 14x7=98).
Retention RateWeek 8Retention rate was determined by the percentage of participants who completed all study visits.
Number of Cigarettes Smoked Per DayWeek 4 and Week 8The number of cigarettes smoked per day was measured using Timeline Follow-Back (TLFB). TLFB is a method in which participants used a physical calendar to self-report the number of cigarettes smoked per day over the prior 14-day period in order to evaluate ongoing tobacco usage.
Number of Participants With Toxicology-verified Cannabis AbstinenceWeek 4 and Week 8The number of participants with Toxicology-verified cannabis abstinence was determined by applying the TLFB method and then biochemically confirming the number of participants with a urine tetrahydrocannabinol (THC) levels less than 50 ng/ml.
Number of Participants With Biochemically-verified Tobacco AbstinenceWeek 4 and Week 8The number of participants with biochemically-verified tobacco abstinence was determined by applying the TLFB method and then biochemically verified by measuring participant levels of expired carbon monoxide \< 8 parts per million (CO \< 8ppm). The Bedfont Smokerlyzer carbon monoxide monitor was used in the analysis.
Mean Expired Carbon MonoxideWeek 4 and Week 8Mean expired carbon monoxide (CO) per participant was measured using the Bedfont Smokerlyzer carbon monoxide monitor. Results reported in mean parts per million (ppm)
Number of Participants With Treatment-Emergent Suicidal Ideation EventsWeek 4 and Week 8The number of participants with treatment-emergent suicidal ideation events was determined using the Columbia Suicide Severity Rating Scale (C-SSRS). The C-SSRS contains 6 yes or no questions in which respondents are asked to indicate whether they have experienced several thoughts or feelings relating to suicide over the past month and behaviors over their lifetime as well as during the past 3 months. An answer of yes to any of the six questions may indicate a need for referral to a trained mental health professional and an answer of yes to questions to the final three questions indicates high-risk.
Frequency of Cannabis UseWeek 4 and Week 8The frequency of cannabis use per day was evaluated over the prior 14-day period using the Timeline Follow-Back method (TLFB), a method in which participants used a physical calendar to self-report the number times per days cannabis was used.

Participant flow

Recruitment details

Participants were recruited from an urban, outpatient substance abuse treatment program that offers both intensive behavioral counseling and medication-assisted treatment (MAT) for opioid use disorder. These clinical sites were selected based on being able to successfully recruit and retain participants during prior clinical trials along with an anticipation of high prevalence of persons with frequent cannabis use in the area.

Pre-assignment details

193 individuals in treatment at an outpatient substance use disorder treatment program were screened for eligibility. Of the 186 participants who were not enrolled and randomized, 182 were ineligible and 4 declined to participate. Seven participants were eligible and enrolled and randomized into the eight-week, open-label, within-subject cross over trial.

Participants by arm

ArmCount
All Study Participants
Participants received either four weeks of standard clinical care (SCC) in an outpatient substance use disorder treatment program followed by four weeks of standard clinical care (SCC) plus varenicline treatment (SCC and VT) or four weeks of standard clinical care (SCC) plus varenicline treatment (SCC and VT) followed by four weeks of standard clinical care (SCC) in an outpatient substance use disorder treatment program as detailed in the Participant Flow Arm/Group Description
7
Total7

Baseline characteristics

CharacteristicAll Study Participants
Age, Continuous49 years
STANDARD_DEVIATION 10
Cannabis Craving43 score on a scale
STANDARD_DEVIATION 20
Cannabis Withdrawal10 score on a scale
STANDARD_DEVIATION 11
Frequency of Cannabis Use4 Cannabis use per day
STANDARD_DEVIATION 0.5
Mean expired carbon monoxide (CO)9 parts per million (ppm)
STANDARD_DEVIATION 6
Number of Cigarettes Smoked Per Day13 Cigarettes smoked per day
STANDARD_DEVIATION 9
Number of participants with biochemically-verified tobacco abstinence1 Participants
Number of participants with Toxicology-verified cannabis abstinence1 Participants
Quantity of Cannabis Use77 percentage of days
Race/Ethnicity, Customized
Black or African American
2 Participants
Race/Ethnicity, Customized
Hispanic or Latino
4 Participants
Race/Ethnicity, Customized
Non-Hispanic White
1 Participants
Region of Enrollment
United States
7 participants
Sex: Female, Male
Female
1 Participants
Sex: Female, Male
Male
6 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 70 / 7
other
Total, other adverse events
0 / 75 / 7
serious
Total, serious adverse events
0 / 70 / 7

Outcome results

Primary

Enrollment Rate

Percentage of the eleven eligible subjects willing to participate

Time frame: Baseline

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
All Study ParticipantsEnrollment Rate7 Participants
Secondary

Cannabis Craving

Cannabis craving was assessed using the Marijuana Craving Questionnaire-Short Form (MCQ-SF). The MCQ-SF is a valid and reliable, self-report instrument with 12 items rated on a 7-point Likert scale from 1 (strongly disagree) to 7 (strongly agree). The 12 items are grouped by certain characteristics and the score of each of resulting groups correlates to the intensity of the four craving dimensions (compulsivity, emotionality, expectancy, and purposefulness). Scores from the four subscales are summed with total possible scores ranging from 12 - 84. Higher scores are indicative of increased craving.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (MEAN)Dispersion
All Study ParticipantsCannabis CravingSCC34 score on a scaleStandard Deviation 20
All Study ParticipantsCannabis CravingSCC+VT35 score on a scaleStandard Deviation 23
Secondary

Cannabis Withdrawal

Cannabis withdrawal was measured by the 15-item version of the Marijuana Withdrawal Checklist (MWC). Participants rated each symptom experienced during their most recent period of marijuana abstinence, based on a 4-point scale where 0 = none, 1 = mild, 2 = moderate, and 3 = severe. A total MWC score was obtained by summing the responses. Possible total scoring ranges from 0 - 45, with 0 signifying no withdrawal symptoms and 45 signifying the most severe withdrawal symptoms.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (MEAN)Dispersion
All Study ParticipantsCannabis WithdrawalSCC4 score on a scaleStandard Deviation 6
All Study ParticipantsCannabis WithdrawalSCC+VT4 score on a scaleStandard Deviation 5
Secondary

Frequency of Cannabis Use

The frequency of cannabis use per day was evaluated over the prior 14-day period using the Timeline Follow-Back method (TLFB), a method in which participants used a physical calendar to self-report the number times per days cannabis was used.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (MEAN)Dispersion
All Study ParticipantsFrequency of Cannabis UseSCC3 Cannabis use per dayStandard Deviation 0.4
All Study ParticipantsFrequency of Cannabis UseSCC+VT2 Cannabis use per dayStandard Deviation 0.3
Secondary

Mean Expired Carbon Monoxide

Mean expired carbon monoxide (CO) per participant was measured using the Bedfont Smokerlyzer carbon monoxide monitor. Results reported in mean parts per million (ppm)

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (MEAN)Dispersion
All Study ParticipantsMean Expired Carbon MonoxideSCC13 parts per million (ppm)Standard Deviation 9
All Study ParticipantsMean Expired Carbon MonoxideSCC+VT14 parts per million (ppm)Standard Deviation 11
Secondary

Number of Cigarettes Smoked Per Day

The number of cigarettes smoked per day was measured using Timeline Follow-Back (TLFB). TLFB is a method in which participants used a physical calendar to self-report the number of cigarettes smoked per day over the prior 14-day period in order to evaluate ongoing tobacco usage.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (MEAN)Dispersion
All Study ParticipantsNumber of Cigarettes Smoked Per DaySCC5 Cigarettes smoked per dayStandard Deviation 7
All Study ParticipantsNumber of Cigarettes Smoked Per DaySCC+VT5 Cigarettes smoked per dayStandard Deviation 7
Secondary

Number of Participants With Biochemically-verified Tobacco Abstinence

The number of participants with biochemically-verified tobacco abstinence was determined by applying the TLFB method and then biochemically verified by measuring participant levels of expired carbon monoxide \< 8 parts per million (CO \< 8ppm). The Bedfont Smokerlyzer carbon monoxide monitor was used in the analysis.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
All Study ParticipantsNumber of Participants With Biochemically-verified Tobacco AbstinenceSCC2 Participants
All Study ParticipantsNumber of Participants With Biochemically-verified Tobacco AbstinenceSCC+VT1 Participants
Secondary

Number of Participants With Toxicology-verified Cannabis Abstinence

The number of participants with Toxicology-verified cannabis abstinence was determined by applying the TLFB method and then biochemically confirming the number of participants with a urine tetrahydrocannabinol (THC) levels less than 50 ng/ml.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
All Study ParticipantsNumber of Participants With Toxicology-verified Cannabis AbstinenceSCC1 Participants
All Study ParticipantsNumber of Participants With Toxicology-verified Cannabis AbstinenceSCC+VT1 Participants
Secondary

Number of Participants With Treatment-Emergent Adverse Events: Upset Stomach

The number of participants with a self-reported adverse event of upset stomach was determined using a structured questionnaire of common varenicline symptoms

Time frame: Upon conclusion of SCC+VT treatment (4 weeks or 8 weeks based on randomization to arm/group)

Population: While receiving standard clinical care without Varenicline participants were not assessed for Varenicline associated adverse effects. In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureValue (NUMBER)
All Study ParticipantsNumber of Participants With Treatment-Emergent Adverse Events: Upset Stomach5 participants
Secondary

Number of Participants With Treatment-Emergent Suicidal Ideation Events

The number of participants with treatment-emergent suicidal ideation events was determined using the Columbia Suicide Severity Rating Scale (C-SSRS). The C-SSRS contains 6 yes or no questions in which respondents are asked to indicate whether they have experienced several thoughts or feelings relating to suicide over the past month and behaviors over their lifetime as well as during the past 3 months. An answer of yes to any of the six questions may indicate a need for referral to a trained mental health professional and an answer of yes to questions to the final three questions indicates high-risk.

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
All Study ParticipantsNumber of Participants With Treatment-Emergent Suicidal Ideation EventsSCC0 Participants
All Study ParticipantsNumber of Participants With Treatment-Emergent Suicidal Ideation EventsSCC+VT0 Participants
Secondary

Number of Participants With Treatment-Emergent Symptoms of Major Depressive Disorder

The number of participants with self-reported Treatment-Emergent symptoms of major depressive disorder was determined using the MINI International Neuropsychiatric Interview (M.I.N.I), a short structured diagnostic interview tool used to assess DSM-IV and ICD-10 psychiatric disorders

Time frame: Upon conclusion of SCC+VT treatment (4 weeks or 8 weeks based on randomization to arm/group)

Population: While receiving standard clinical care without Varenicline participants were not assessed for Varenicline associated adverse effects. In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
All Study ParticipantsNumber of Participants With Treatment-Emergent Symptoms of Major Depressive Disorder1 Participants
Secondary

Overall Medication Adherence

Overall medication adherence was calculated as a percentage based on the number of pills prescribed during the study, corrected for the number of pills returned, divided by the period (in days), and multiplied by 100. An aggregate percentage of pills was calculated and reported for all seven study participants.

Time frame: Upon conclusion of SCC+Varenicline treatment (4 weeks or 8 weeks based on randomization to arm/group)

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureValue (NUMBER)
All Study ParticipantsOverall Medication Adherence62 Percentage of pills
Secondary

Quantity of Cannabis Use

The quantity of cannabis use over the prior 14-day period was measured using the Timeline Follow-Back (TLFB) method. TLFS is a method in which participants used a physical calendar to quantify the number of days over a specified period of time (in this study 14 days) during which cannabis was used. An aggregate value for percentage of days of cannabis use was calculated by tabulating the total number of days cannabis was used by all study participants over the prior 14-day period and dividing by the total number of calendar days over this period across the 7 participants (i.e., 14x7=98).

Time frame: Week 4 and Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureGroupValue (NUMBER)
All Study ParticipantsQuantity of Cannabis UseSCC82 percentage of days
All Study ParticipantsQuantity of Cannabis UseSCC+VT60 percentage of days
Secondary

Retention Rate

Retention rate was determined by the percentage of participants who completed all study visits.

Time frame: Week 8

Population: In a deviation from the trial design, one participant completed SCC alone for two weeks, then SCC+VT for four weeks, followed by SCC alone for two weeks.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
All Study ParticipantsRetention Rate7 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026