Tobacco Use DisorderPhase 4NCT05729243
Cytisine for Smoking Cessation
A Phase 4 study testing Cytisine in people with Tobacco Use Disorder and Alcohol Use Disorder, run by Centre for Addiction and Mental Health at 1 site in Canada.
Trial summary
The goal of this clinical trial is to evaluate the safety and effectiveness of cytisine as a smoking cessation treatment in individuals with concurrent alcohol use disorder. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Tobacco Use Disorder, Alcohol Use Disorder, Smoking Cessation
- What is being tested?
- Cytisine
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 20 participants
- Where
- 1 siteCanada
- Study dates
- 8 Feb 2023to 12 Dec 2025
- Phase
- Phase 4
- Are there results?
- None posted in the registry
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 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Aged 18-65 years;
- Have TUD assessed by structured clinical interview for DSM-5;
- Have past year AUD (active) assessed by structured clinical interview for DSM-5;
- Report daily cigarette consumption in past month and expired carbon monoxide (CO) measurement ≥10ppm at screening;
- Have Fagerstrom Test of Nicotine Dependence (FTND55) score ≥4;
- Have motivation to quit within 30 days i.e. Contemplation Ladder56 score ≥7;
- Be willing and able to comply with all study procedural and assessment demands;
- Be able to provide voluntary written informed consent.
Who cannot join
- Report prolonged smoking abstinence in the past month preceding screening;
- Be using other smoking cessation aids
- Enrolled in another smoking cessation program
- Be pregnant, breastfeeding, or intending to become pregnant or breastfeed;
- Exhibit suicidal thoughts or behavior in the past month;
- Enrolled in another study which would interfere with study procedures or represent a potential risk to the participant
- Have a serious unstable psychiatric or medical condition preventing participation in the trial. This includes some forms of schizophrenia, ischemic heart disease, heart failure, arterial hypertension (systolic BP above 150; diastolic BP above 100), cerebrovascular diseases, occlusion of blood vessels, kidney and/or liver disease, hyperthyroidism, ulcer, diabetes, Chromaffin tumours of the adrenal medulla, and gastroesophageal reflux disease (GERD)
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Cytisine: Testing Its Potential as a Therapeutic Strategy for Smoking Cessation Among People With Concurrent Alcohol Use Disorder
The goal of this clinical trial is to evaluate the safety and effectiveness of cytisine as a smoking cessation treatment in individuals with concurrent alcohol use disorder.
- Being tested
- Cytisine, Placebo
- Medical subject headings
- Tobacco Use Disorder, Alcoholism, Smoking Cessation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CytisineDrug
Cytisine is a nicotinic acetylcholine receptor partial agonist and is a natural health product approved by Health Canada. Cytisine has been used for a long time in Europe for smoking cessation.
PlaceboOther
A placebo identical in appearance to cytisine will be used
| Study group | Role | What they receive |
|---|---|---|
| Cytisine | Experimental | Cytisine will be given as 1.5 mg tablet formulations for 25 days.
The following treatment schedule will be followed:
* Days 1 to 3: 1.5 mg taken every 2 hours (6 pills (9 mg)/day)
* Days 4 to 12: 1.5 mg taken every 2.5 hours (5 pills (7.5 mg)/day)
* Days 13 to 16: 1.5 mg taken every 3 hours (4 pills (6 mg)/day)
* Days 17 to 20: Taper down to 1 tablet every 5 hours (3 pills (4.5 mg)/day)
* Days 21 to 25: Taper down to 1-2 tablets daily (1.5-3 mg/day) Receives: Drug: Cytisine |
| Placebo | Placebo comparator | Placebo will be given following the same schedule as the Cytisine Arm. Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Frequency and type of adverse events
To assess the tolerability of cytisine
Measured: Total duration of trial (24 weeks)
Rate of retention in the trial: number of sessions completed for each participant and number ofparticipants who withdraw
To assess the tolerability of cytisine
Measured: Total duration of trial (24 weeks)
Secondary outcomes (8)
Point-prevalence abstinence
Complete abstinence ("not even a puff") during a designated time period (7 days) prior to assessment. This will be measured at each assessment point (e.g., 2 and 4wk).
Measured: Week 2 and week 4
Repeated point-prevalence abstinence
Point-prevalence abstinence at each consecutive assessment point.
Measured: Throughout study completion, up to 24 weeks.
Prolonged abstinence
Complete abstinence ("not even a puff") after an initial grace period; also known as sustained abstinence.
Measured: This period will end at the end of treatment (day 25) or at final follow-up.
Prolonged abstinence with lapses
Prolonged abstinence after a grace period, but some smoking is allowed (e.g., no more than 5 cigarettes; fewer than seven consecutive days of smoking).
Measured: This period will end at the end of treatment (day 25) or at final follow-up.
Continuous Abstinence
Complete abstinence ("not even a puff") beginning on the TQD (i.e., with no grace period) and lasting until the assessment from target quit date (week 2) to end of treatment (day 25) and at final follow up.
Measured: Throughout study completion, up to 24 weeks.
Physical dependence to Nicotine in Participants
The Fagerstrom Test for Nicotine Dependence (FTND) will be used to assess physical dependence in participants.
Measured: Throughout study duration (24 weeks)
Nicotine Withdrawal Symptoms in Participants
The Minnesota Nicotine Withdrawal Scale (MNWS) will be used to assess nicotine withdrawal symptoms.
Measured: Throughout study duration (24 weeks)
Nicotine Craving in Participants
Tiffany Questionnaire of Smoking Urges (QSU) will be used to assess nicotine craving.
Measured: Throughout study duration (24 weeks)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Feb 2023
- Study start8 Feb 2023
- Primary completion12 Dec 2025
- Study completion12 Dec 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Tobacco Use DisorderStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- Centre for Addiction and Mental Health
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Bernard Le Foll, Centre for Addiction and Mental Health
- Investigators
- Bernard Le Foll, Principal investigator, The Centre for Addiction and Mental Health
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05729243
- Sponsor's protocol ID
- 054-2022
- Status last verified
- Feb 2026
- First submitted
- 24 Jan 2023
- Last updated
- 27 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Cytisine: Testing Its Potential as a Therapeutic Strategy for Smoking Cessation Among People With Concurrent Alcohol Use Disorder
- ClinicalTrials.gov ID
- NCT05729243
- Acronym / sponsor ID
- 054-2022
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- Centre for Addiction and Mental HealthUniversity, hospital or other
- Study start
- 8 Feb 2023 (actual)
- Primary completion
- 12 Dec 2025 (actual)
- Study completion
- 12 Dec 2025 (actual)
- First posted
- 15 Feb 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to evaluate the safety and effectiveness of cytisine as a smoking cessation treatment in individuals with concurrent alcohol use disorder.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Cytisine | Experimental | Drug: CytisineCytisine will be given as 1.5 mg tablet formulations for 25 days. The following treatment schedule will be followed: * Days 1 to 3: 1.5 mg taken every 2 hours (6 pills (9 mg)/day) * Days 4 to 12: 1.5 mg taken every 2.5 hours (5 pills (7.5 mg)/day) * Days 13 to 16: 1.5 mg taken every 3 hours (4 pills (6 mg)/day) * Days 17 to 20: Taper down to 1 tablet every 5 hours (3 pills (4.5 mg)/day) * Days 21 to 25: Taper down to 1-2 tablets daily (1.5-3 mg/day) |
| Placebo | Placebo comparator | Other: PlaceboPlacebo will be given following the same schedule as the Cytisine Arm. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Aged 18-65 years;
- Have TUD assessed by structured clinical interview for DSM-5;
- Have past year AUD (active) assessed by structured clinical interview for DSM-5;
- Report daily cigarette consumption in past month and expired carbon monoxide (CO) measurement ≥10ppm at screening;
- Have Fagerstrom Test of Nicotine Dependence (FTND55) score ≥4;
Key exclusion criteria (7 listed)
- Report prolonged smoking abstinence in the past month preceding screening;
- Be using other smoking cessation aids
- Enrolled in another smoking cessation program
- Be pregnant, breastfeeding, or intending to become pregnant or breastfeed;
- Exhibit suicidal thoughts or behavior in the past month;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CytisineCytisine is a nicotinic acetylcholine receptor partial agonist and is a natural health product approved by Health Canada. Cytisine has been used for a long time in Europe for smoking cessation. | Drug | Cytisine |
| PlaceboA placebo identical in appearance to cytisine will be used | Other | Placebo |
Primary outcome
Frequency and type of adverse events
Time frame: Total duration of trial (24 weeks)
To assess the tolerability of cytisine
Rate of retention in the trial: number of sessions completed for each participant and number ofparticipants who withdraw
Time frame: Total duration of trial (24 weeks)
To assess the tolerability of cytisine
8 secondary outcomes
Point-prevalence abstinence
Time frame: Week 2 and week 4
Repeated point-prevalence abstinence
Time frame: Throughout study completion, up to 24 weeks.
Prolonged abstinence
Time frame: This period will end at the end of treatment (day 25) or at final follow-up.
Prolonged abstinence with lapses
Time frame: This period will end at the end of treatment (day 25) or at final follow-up.
Continuous Abstinence
Time frame: Throughout study completion, up to 24 weeks.
Physical dependence to Nicotine in Participants
Time frame: Throughout study duration (24 weeks)
Nicotine Withdrawal Symptoms in Participants
Time frame: Throughout study duration (24 weeks)
Nicotine Craving in Participants
Time frame: Throughout study duration (24 weeks)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Feb 2026.
Related trials for Tobacco Use Disorder
Recruiting
Developing an E-Cigarette Cessation Intervention for Hispanic/Latina(o) Youth in Florida: The BReATHE Study
Vaping Teens, Vaping Behaviors
Recruiting
Adaptation and Testing of a Novel Text-based Tobacco Cessation and Education Intervention in Kenyan Emergency Department Patients
Tobacco Use, Tobacco Use Cessation
Recruiting
STEPS: Substance Use Trial of E-cigarettes or Pharmacotherapy for Smoking
Tobacco Use, Substance Use Disorders
Recruiting
Project Q: Cue-based Treatment Intervention to Promote Cessation Among People Who Smoke Lightly or Non-daily
Tobacco Use Disorder
Recruiting
Use of Nicotine Pouches Among Daily Smokers
Tobacco Dependence
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Bernard Le Foll principal investigator
The Centre for Addiction and Mental Health
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Cytisine in people with Tobacco Use Disorder and Alcohol Use Disorder, run by Centre for Addiction and Mental Health at 1 site in Canada.
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 8 inclusion and 7 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 27 Feb 2026. 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 Canada. 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. Some participants in this study may receive a placebo. 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 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
Frequency and type of adverse events (time frame: Total duration of trial (24 weeks)). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 27 Feb 2026.