Cytisine for Smoking Cessation

NCT05729243 | Completed Phase 4

• 1 other identifier: 054-2022
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief 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.

Conditions

Tobacco Use Disorder; Alcohol Use Disorder; Smoking Cessation

Outcome Measures

Primary Outcomes (2)

• Frequency and type of adverse events

  To assess the tolerability of cytisine

  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

  Total duration of trial (24 weeks)

Secondary Outcomes (8)

• Point-prevalence abstinence

  Week 2 and week 4

• Repeated point-prevalence abstinence

  Throughout study completion, up to 24 weeks.

• Prolonged abstinence

  This period will end at the end of treatment (day 25) or at final follow-up.

• Prolonged abstinence with lapses

  This period will end at the end of treatment (day 25) or at final follow-up.

• Continuous Abstinence

  Throughout study completion, up to 24 weeks.

Other Outcomes (6)

• Tertiary Endpoints to evaluate the impact of cytisine vs. placebo on anxiety.

  Throughout study duration (24 weeks)

• Tertiary Endpoints to evaluate the impact of cytisine vs. placebo on mood.

  Throughout study duration (24 weeks)

• Tertiary Endpoints to evaluate the impact of cytisine vs. placebo on Quality of Life.

  Throughout study duration (24 weeks)

Study Arms (2)

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)

Drug: Cytisine

Placebo

PLACEBO COMPARATOR

Placebo will be given following the same schedule as the Cytisine Arm.

Other: Placebo

Interventions

Cytisine DRUG

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.

Cytisine

Placebo OTHER

A placebo identical in appearance to cytisine will be used

Placebo

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

You may not qualify if:

• 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)

Sponsors & Collaborators

• Centre for Addiction and Mental Health: lead

Study Sites (1)

Center for Addiction and Mental Health

Toronto, Ontario, M5S 2S1, Canada

Location

MeSH Terms

Conditions

Tobacco Use Disorder; Alcoholism; Smoking Cessation

Interventions

cytisine

Condition Hierarchy (Ancestors)

Substance-Related Disorders; Chemically-Induced Disorders; Mental Disorders; Alcohol-Related Disorders; Health Behavior; Behavior

Study Officials

• Bernard Le Foll

  The Centre for Addiction and Mental Health

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: January 24, 2023
• First Posted: February 15, 2023
• Study Start: February 8, 2023
• Primary Completion: December 12, 2025
• Study Completion: December 12, 2025
• Last Updated: February 27, 2026

Record last verified: 2026-02

Locations

CA (1)