Effectiveness of varenicline as an aid to smoking cessation: results of an inter-European observational study

Varenicline tartrate, a selective partial agonist of the alpha alpha 4 beta beta 2 nicotinic receptor, has been shown to be an effective smoking cessation aid with an acceptable safety profile in a number of randomized, controlled trials. The aim of the CHOICES (Champix Observational Investigation in the Cessation of Smoking) study was to investigate the effectiveness and safety of varenicline in real-world clinical practice. The CHOICES study was a 12-week, prospective, observational, non-comparative study of varenicline conducted in four European countries (Belgium, Greece, Hungary, and Slovenia) between November 21, 2007 and August 3, 2009. Participants were prescribed varenicline according to the recommendations on the European Summary of Product Characteristics (SmPC). Smoking abstinence rates in the 7 days between week 11 and 12 were determined based on verbal reporting using a nicotine use inventory. The safety profile of varenicline was also assessed. Of 566 participants enrolled in this study, 551 received varenicline and were evaluated for effectiveness and safety. At baseline, the overall study population had a mean age of 45.5 years; a mean history of smoking of 27.0 years; and a mean score on the Fagerstroom Test of Nicotine Dependence (FTND) of 6.1. Overall, 64.6%% (95%% CI 60.1, 68.3) of participants successfully quit smoking by the end of the treatment phase at week 12. The most frequent treatment-emergent (all causality) adverse events were nausea (8.9%%), insomnia (2.9%%), and sleep disorder (2.2%%) of mostly mild or moderate intensity. Discontinuations from the study due to treatment-related adverse events occurred in 3.4%% of participants. Abstinence rates were not validated by carbon monoxide measurements, as this is not a practice uniformly used in European countries. The CHOICES study shows that in a real-world clinical practice setting outside a clinical trial environment, varenicline is an effective smoking cessation aid with an acceptable safety profile. ClinicalTrials.gov identifier: NCT00669240.