Immediate versus delayed quitting and rates of relapse among smokers treated successfully with varenicline, bupropion SR or placebo

Addiction. 2010 Nov;105(11):2002-13. doi: 10.1111/j.1360-0443.2010.03058.x. Epub 2010 Sep 1.


Aims: We assessed to what degree smokers who fail to quit on the target quit date (TQD) or lapse following TQD eventually achieve success with continued treatment.

Design: A secondary analysis of pooled data of successful quitters treated with varenicline (306 of 696), bupropion (199 of 671) and placebo (121 of 685) from two identically-designed clinical trials of varenicline versus bupropion sustained-release and placebo.

Setting: Multiple research centers in the US.

Participants: Adult smokers (n==2052) randomized to 12 weeks drug treatment plus 40 weeks follow-up.

Measurement: The primary end-point for the trials was continuous abstinence for weeks 9-12. TQD was day 8. Two patterns of successful quitting were identified. Immediate quitters (IQs) were continuously abstinent for weeks 2-12. Delayed quitters (DQs) smoked during 1 or more weeks for weeks 2-8.

Findings: Cumulative continuous abstinence (IQs + DQs) increased for all treatments during weeks 3-8. Overall IQs and DQs for varenicline were (24%; 20%) versus bupropion (18.0%, P=0.007; 11.6%, P<0.001) or placebo (10.2%, P<0.001; 7.5%, P<0.001). However, DQs as a proportion of successful quitters was similar for all treatments (varenicline 45%; bupropion 39%; placebo 42%) and accounted for approximately one-third of those remaining continuously abstinent for weeks 9-52. No gender differences were observed by quit pattern. Post-treatment relapse was similar across groups.

Conclusions: Our data support continuing cessation treatments without interruption for smokers motivated to remain in the quitting process despite lack of success early in the treatment.

Trial registration: NCT00141206 NCT00143364.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Benzazepines / therapeutic use*
  • Breath Tests
  • Bupropion / therapeutic use*
  • Carbon Monoxide / analysis
  • Delayed-Action Preparations
  • Dopamine Uptake Inhibitors / therapeutic use*
  • Drug Labeling
  • Female
  • Health Knowledge, Attitudes, Practice
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Motivation
  • Nicotinic Agonists / therapeutic use*
  • Placebos
  • Quinoxalines / therapeutic use*
  • Secondary Prevention
  • Smoking / drug therapy*
  • Smoking Cessation / methods
  • Smoking Cessation / psychology
  • Smoking Cessation / statistics & numerical data*
  • Substance Withdrawal Syndrome / drug therapy
  • Time Factors
  • Treatment Outcome
  • Varenicline
  • Young Adult


  • Benzazepines
  • Delayed-Action Preparations
  • Dopamine Uptake Inhibitors
  • Nicotinic Agonists
  • Placebos
  • Quinoxalines
  • Bupropion
  • Carbon Monoxide
  • Varenicline

Associated data