Retreatment with varenicline for smoking cessation in smokers who have previously taken varenicline: a randomized, placebo-controlled trial

Abstract

The efficacy and safety of retreatment with varenicline in smokers attempting to quit were evaluated in this randomized, double-blind, placebo-controlled, multicenter trial (Australia, Belgium, Canada, the Czech Republic, France, Germany, the United Kingdom, and the United States). Participants were generally healthy adult smokers (≥ 10 cigarettes/day) with ≥ 1 prior quit attempt (≥ 2 weeks) using varenicline and no quit attempts in ≤ 3 months; they were randomly assigned (1:1) to 12 weeks' varenicline (n = 251) or placebo (n = 247) treatment, with individual counseling, plus 40 weeks' nontreatment follow-up. The primary efficacy end point was the carbon monoxide-confirmed (≤ 10 ppm) continuous abstinence rate for weeks 9-12, which was 45.0% (varenicline; n = 249) vs. 11.8% (placebo; n = 245; odds ratio: 7.08; 95% confidence interval: 4.34, 11.55; P < 0.0001). Common varenicline group adverse events were nausea, abnormal dreams, and headache, with no reported suicidal behavior. Varenicline is efficacious and well tolerated in smokers who have previously taken it. Abstinence rates are comparable with rates reported for varenicline-naive smokers.

Trial registration: ClinicalTrials.gov NCT01244061.

Figure 1

Participant disposition.

Figure 2

Continuous abstinence rates (CARs), defined as the percentage of participants remaining continuously abstinent from week 9 to each in-clinic visit through week 52. ORs shown are for CAR during weeks 9–12 (primary end point) and for CARs during weeks 9–24 and 9–52 (secondary end points). CI, confidence interval; N, number of participants who received ≥1 dose, including partial doses, of randomized study drug; OR, odds ratio.

Figure 3

Mean 7-day point prevalence of abstinence, defined as the percentage of participants remaining abstinent from cigarette smoking and use of other nicotine and/or tobacco products in the previous 7 days. CI, confidence interval; N, number of participants who received ≥1 dose, including partial doses, of randomized study drug; OR, odds ratio.