Conditions: Smoking Cessation
Keywords: Smoking Cessation Chantix varenicline Nicotine Replacement Therapy Nicotine Patches Zyban bupropion Quit Smoking
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 606
Healthy volunteers: no

Brief summary:
Nicotine replacement therapy (NRT) is a well-tolerated and efficacious smoking cessation treatment, and yet many smokers fail to quit using NRT. Many of these smokers may benefit from prescription treatment alternatives, including Zyban or Chantix. In this study, the investigators propose to develop and evaluate a stepped-care treatment algorithm that would evaluate whether smokers who receive treatment with NRT should be supplemented with Zyban or switched to Chantix only based on: 1) their initial response to NRT; and 2) individual genetic factors found to predict smoking cessation in other studies evaluating these treatments. This study is a continuation of our previous studies showing that abstinence rates can be increased by starting nicotine patch therapy two weeks before the quit date. The investigators will provide pre-cessation NRT to all participants initially. Those who do not show a favorable response on early indicators of success (e.g., smoking in the first week after the target quit-smoking date) will receive "rescue" treatment by having their NRT treatment supplemented with Zyban , by being switched to treatment with Chantix or will remain on NRT (control).

The investigators hypothesize that "Rescue" treatment with Zyban in combination with NRT or Chantix will increase success rates over leaving subjects on NRT when they are NRT insufficient responders, i.e. they have shown an unfavorable response to NRT in the first week pre-quit or the first week post-quit.

Detailed description:

Arms:
arm 1: Nicotine Responders arm 2: Participants not responsive to nicotine patches who are randomly assigned at week 2 to use of Zyban (bupropion) in combination with nicotine patches arm 3: Participants not responsive to nicotine patches who are randomly assigned at week 2 to use of Chantix (varenicline) arm 4: Participants not responsive to nicotine patches who are randomly assigned at week 2 to continued use of nicotine patches arm 5: Participants not responsive to nicotine patches who are randomly assigned at week 4 to use of Zyban (bupropion) in combination with nicotine patches arm 6: Participants not responsive to nicotine patches who are randomly assigned at week 4 to use of Chantix (varenicline) arm 7: Participants not responsive to nicotine patches who are randomly assigned at week 4 to continued use of nicotine patches

Interventions: intervention 1: Nicotine Patches intervention 2: Nicotine patches, then bupropion & nicotine patches (Pre-Quit) intervention 3: Nicotine patches, then varenicline (Pre-Quit) intervention 4: Nicotine patches, then nicotine patches (Pre-Quit) intervention 5: Nicotine patches, then bupropion & nicotine patches (Post-Quit) intervention 6: Nicotine patches, then varenicline (Post-Quit) intervention 7: Nicotine patches, then nicotine patches (Post-Quit)
Intervention descriptions: intervention 1: 21mg (1 patch) or 42mg (2 patches)nicotine patches for first five weeks (# of daily patches based on baseline carbon monoxide level); 21mg nicotine patch for 4 weeks; 14mg nicotine patch for 2 weeks and 7mg nicotine patch for 2 weeks. intervention 2: 21mg (1 patch) or 42mg (2 patches) nicotine patches for first week (# of daily patches based on baseline carbon monoxide level); starting with week 2: 150mg of bupropion once daily and 21mg (1 patch) or 42mg (2 patches)nicotine patches for first 3 days (# of daily patches based on baseline carbon monoxide level); 150mg of bupropion twice daily and 21mg (1 patch) or 42mg (2 patches)nicotine patches for 3 weeks and 4 days (# of daily patches based on baseline carbon monoxide level); 150mg of bupropion twice daily and 21mg nicotine patch for 4 weeks; 150mg of bupropion twice daily and 14mg nicotine patch for 2 weeks and 150mg of bupropion twice daily and 7mg nicotine patch for 2 weeks. intervention 3: 21mg (1 patch) or 42mg (2 patches) nicotine patches for first week (# of daily patches based on baseline carbon monoxide level); starting with week 2: 0.5mg of varenicline once daily for first 3 days; 0.5mg of varenicline twice daily for the next 4 days; and 1mg of varenicline twice daily for the remainder of the study (11 weeks) intervention 4: 21mg (1 patch) or 42mg (2 patches)nicotine patches for first five weeks (# of daily patches based on baseline carbon monoxide level); 21mg nicotine patch for 4 weeks; 14mg nicotine patch for 2 weeks and 7mg nicotine patch for 2 weeks. intervention 5: 21mg (1 patch) or 42mg (2 patches) nicotine patches for first three weeks (# of daily patches based on baseline carbon monoxide level); starting with week 4: 150mg of bupropion once daily and 21mg (1 patch) or 42mg (2 patches) nicotine patches for first 3 days (# of daily patches based on baseline carbon monoxide level); 150mg of bupropion twice daily and 21mg (1 patch) or 42mg (2 patches) nicotine patches for 3 weeks and 4 days (# of daily patches based on baseline carbon monoxide level); 150mg of bupropion twice daily and 21mg nicotine patch for 4 weeks; 150mg of bupropion twice daily and 14mg nicotine patch for 2 weeks and 150mg of bupropion twice daily and 7mg nicotine patch for 2 weeks. intervention 6: 21mg (1 patch) or 42mg (2 patches) nicotine patches for first three weeks (# of daily patches based on baseline carbon monoxide level); starting with week 4: 0.5mg of varenicline once daily for first 3 days; 0.5mg of varenicline twice daily for the next 4 days; and 1mg of varenicline twice daily for the remainder of the study (11 weeks) intervention 7: 21mg (1 patch) or 42mg (2 patches) nicotine patches for first seven weeks (# of daily patches based on baseline carbon monoxide level); 21mg nicotine patch for 4 weeks; 14mg nicotine patch for 2 weeks and 7mg nicotine patch for 2 weeks.

Protocol document: