Using Non-invasive Brain Stimulation (tDCS) With Varenicline for Treating Tobacco Dependence
Condition: Tobacco Dependence; Smoking Cessation; Tobacco Smoking; Tobacco Use Disorder; Substance Use Disorders; Molecular Mechanisms of Pharmacological Action; Physiological Effects of Drugs
MeSH terms: Substance-Related Disorders; Tobacco Use Disorder
Study type: Interventional

Summary: 
      The addition of tDCS as an adjunct to pharmacotherapy is a novel approach but one that is
      grounded in a growing evidence-base.The primary objective of this research is to provide
      preliminary evidence of the effectiveness of tDCS as an adjunct treatment to pharmacotherapy
      for smoking cessation. The investigators hypothesize that the addition of active tDCS to the
      left DLPFC will improve the effectiveness of varenicline as reflected by higher quit rates at
      end of treatment compared to the sham group. Smoking status will be biochemically confirmed
      at various time points using expired cotinine measures. Furthermore, the investigators will
      be collecting neuroimaging (fMRI) data as well as measures of attentional bias to explore the
      neurological and physiological correlates from using adjunct tDCS and varenicline therapy.
    

Detailed description: 
      While varenicline on its own is the most effective medication for smoking cessation,
      long-term abstinence is still relatively poor. The primary objective of this study is to
      evaluate the effectiveness of adjunct active tDCS with varenicline in treating tobacco
      dependence. This study is a double-blind, sham-controlled, randomized clinical trial where 50
      daily dependent treatment seeking smokers will be recruited at the Nicotine Dependence Clinic
      in Toronto, Canada. Participants will be receiving twelve weeks of varenicline treatment (1mg
      b.i.d.) and randomized 1:1 to either active tDCS (active: 20 minutes at 2 mA) or sham tDCS
      (30 seconds at 2 mA, 19.5 minutes at 0 mA), daily (M-F) for the first 2 weeks and then every
      2 weeks for the next 10 weeks. There will be 2 fMRI scans at baseline and 1 scan at
      end-of-treatment. Eye-tracking viewing tests will be conducted at baseline, weeks 4, 8, 12
      and at 6 months follow up. During the 6 month follow-up, participants will be answering
      questions regarding their smoking behaviour and craving. Smoking status will be biochemically
      confirmed at each study visit using expired cotinine.
    

Intervention name(s): Varenicline; Active tDCS; Sham tDCS
Intervention type(s): Drug; Device; Device
Intervention description(s): Varenicline (Champix®), Pfizer Canada Inc., Kirkland, Quebec. Dispense for 12 weeks. One tablet (0.5mg) once daily for first three days, then one tablet (0.5 mg) twice daily for next four days, then 1 mg (one 1mg tablet) twice daily for the remainder of 12 weeks. Dose adjustments due to adverse events will be allowed (i.e. decrease to 0.5 mg twice daily).; Active 2mA tDCS (Nuraleve, Canada) with the anode placed over the left dorsolateral prefrontal cortex (dlPFC) and the cathode placed over the right dlPFC for 20 minutes per session; Shame tDCS (Nuraleve, Canada) (30 seconds of 2mA and 19.5 minutes of 0 mA) with the anode placed over the left dorsolateral prefrontal cortex (dlPFC) and the cathode placed over the right dlPFC for 20 minutes per session.
Other intervention name(s): Champix
Intervention MeSH terms: Varenicline
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Sham Controlled Randomized Trial
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Smoking Cessation Medication; Smoking Treatment; Tobacco Treatment; Quitting Smoking; Varenicline; Transcranial Direct Current Stimulation; Neuroimaging; fMRI; Attentional Bias; Eye-tracking; Dependence; Addiction; Cigarettes; Biochemical Confirmation; Cue reactivity; Reward Anticipation; Diffusion Tensor Imaging; Resting State Functional Connectivity; BOLD fMRI; Quantitative T1