Use of Varenicline for 4-weeks Prior to Quitting

Phase 3

Completed

Brief Summary: Varenicline (Champix) is a relatively new medicine that is effective in helping people to quit smoking. It is normally started 1-week before stopping smoking and used for up to 12-24 weeks. We are trying to find out if using varenicline for an extended time (4-weeks) before stopping smoking is better than the standard 1-week of use prior to stopping.

The study will recruit 100 smokers who want to stop. They will be randomly allocated to receive varenicline(4-weeks) or placebo (3-weeks followed by 1-week of active treatment as indicated by standard prescribing practice), followed by a 12-week open label treatment period where all participants will receive varenicline.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Pregnant or breastfeeding
End-stage renal disease
Used varenicline in the past 6 months
Unable to fill in questionnaires in English
Current psychiatric illness
Current serious illness including uncontrolled hypertension and recent cardiac event
Sensitivity to varenicline currently enrolled in other research projects.

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Participants will use 3 weeks of placebo, followed by 1 week of varenicline, prior to quitting
Placebo	Varenicline	Participants will use 3 weeks of placebo, followed by 1 week of varenicline, prior to quitting
Varenicline pre-treatmemt	Varenicline	Participants will use varenicline (1mg BD) 4-weeks prior to quitting

Primary Outcome Measures

Name	Time	Method
Rating of Urges to Smoke 24 Hours and One Week After the Target Quit Date Assessed by Mood and Physical Symptoms Scale	24 hours and 7 days after quit date (week 4)	The scale measures tobacco withdrawal symptoms (depressed, irritable, restless, hungry, poor concentration, slept worse than usual) on 5-point scales from Not at all (rated as 1) to Extremely (rated as 5). It also asks 'How much of the time have you felt the urge to smoke in the last week? and 'How strong have these urges been?'; both rated on 6-point scales with higher numbers=higher craving.

Secondary Outcome Measures

Name	Time	Method
Change in Pre-quit End-expired Carbon Monoxide Reading (CO)	Baseline - week 8	Carbon monoxide concentration is measured in particles per million. It indicates smoke intake. CO was measured at each contact to monitor changes in smoke intake and differences between the study arms.
Change in MPSS Scores of Urges to Smoke and Cigarette Withdrawal Symptoms Throughout the First Four Weeks of Abstinence	Week 4 - 8	Change in the Mood and Physical Symptoms Scale (MPSS)\, scores of urges to smoke and cigarette withdrawal symptoms throughout the first four weeks of abstinence (measured weekly from weeks 4-8). \ The MPSS measures cigarette withdrawal symptoms. The scale is 1-5, 1 being not at all and 5 being extremely (depressed, irritable, restless, hungry, poor concentration, slept worse than usual).
Change in Pre-quit Cotinine Levels	Weeks 1-4 (the first 4-weeks after first medication dose)	Differences in baseline cotinine levels were compared with cotinine levels measured 4 weeks after taking the first medication dose.
Change in Pre-quit Ratings of Cigarette Satisfaction	Baseline - week 4	Satisfaction measured on a scale of 1-5; "Have you found your cigarettes more or less enjoyable than usual in the last week?" 1= much more and 5 = much less
Change in Pre-quit Cigarette Consumption	Baseline - week 4	Participants reported average number of cigarettes smoked per day every week throughout the four week pre-quit period.