Background: The use of varenicline tartrate alleviates postquit withdrawal discomfort, but it also seems to reduce the "reward" associated with smoking. The current treatment schedule, which commences 1 week before quitting, relies primarily on the first mechanism. We set out to determine whether increasing the prequit medication period renders cigarettes less satisfying and facilitates quitting.
Methods: One hundred one smokers attending a stop-smoking clinic in London, United Kingdom, were randomly allocated to receive varenicline for 4 weeks before the target quit date (TQD) or to receive placebo for 3 weeks before the TQD, followed by varenicline for 1 week before the TQD. In both groups, standard varenicline treatment was given for 3 months after the TQD. Measures included smoking satisfaction and smoke intake before quitting, urges to smoke and withdrawal discomfort after quitting, and sustained abstinence from the TQD to 3 months.
Results: Varenicline preloading reduced prequit enjoyment of smoking (P = .004) and smoke intake (P < .001), with 36.7% of participants reducing their cotinine concentrations by more than 50% (reducers). Varenicline preloading did not affect postquit withdrawal symptoms, but it increased 12-week abstinence rates (47.2% in the varenicline arm vs 20.8% in the placebo arm, P = .005). The effect was particularly strong among the reducers in the varenicline arm (66.7% in reducers vs 22.6% in nonreducers, P = .002). Varenicline preloading was well tolerated.
Conclusions: Although several issues remain to be clarified, varenicline preloading can generate a substantial reduction in ad lib smoking and enhance 12-week quit rates. Current treatment schedules may lead to suboptimal treatment results. Trials with longer follow-up periods are needed to corroborate these findings. Trial Registration clinicaltrials.gov Identifier: NCT00789074.