Use of Varenicline for 4-weeks Prior to Quitting

• Change in Pre-quit End-expired Carbon Monoxide Reading (CO) [ Time Frame: Baseline - week 8 ] [ Designated as safety issue: No ]

  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 Pre-quit Cotinine Levels [ Time Frame: Weeks 1-4 (the first 4-weeks after first medication dose) ] [ Designated as safety issue: No ]
  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 [ Time Frame: Baseline - week 4 ] [ Designated as safety issue: No ]
  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 [ Time Frame: Baseline - week 4 ] [ Designated as safety issue: No ]
  Participants reported average number of cigarettes smoked per day every week throughout the four week pre-quit period.
• Change in MPSS Scores of Urges to Smoke and Cigarette Withdrawal Symptoms Throughout the First Four Weeks of Abstinence [ Time Frame: Week 4 - 8 ] [ Designated as safety issue: No ]

  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 end-expired carbon monoxide reading (CO) [ Time Frame: 4-weeks after first medication dose ] [ Designated as safety issue: No ]
• Change in pre-quit cotinine levels [ Time Frame: 4-weeks after first medication dose ] [ Designated as safety issue: No ]
• Change in pre-quit ratings of cigarette satisfaction [ Time Frame: 4-weeks after first medication dose ] [ Designated as safety issue: No ]
• Change in pre-quit cigarette consumption [ Time Frame: 4-weeks after first medication dose ] [ Designated as safety issue: No ]
• Change in MPSS scores of urges to smoke and cigarette withdrawal symptoms throughout the first four weeks of abstinence [ Time Frame: 4-week after quit date ] [ Designated as safety issue: No ]

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.

• Tobacco Dependence
• Smoking Cessation

• Drug: Varenicline
  Varenicline 1mg twice daily
  Other Name: Champix
• Drug: Placebo
  Placebo 1mg BD

• Experimental: Varenicline pre-treatmemt
  Participants will use varenicline (1mg BD) 4-weeks prior to quitting
  Intervention: Drug: Varenicline
• Placebo Comparator: Placebo
  Participants will use 3 weeks of placebo, followed by 1 week of varenicline, prior to quitting
  Interventions:

  • Drug: Varenicline
  • Drug: Placebo

Inclusion Criteria:

• Smokers seeking treatment
• Aged 18 and over
• Consenting to take part in the trial

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.