Effectiveness and safety of varenicline as an aid to smoking cessation: results of an inter-Asian observational study in real-world clinical practice.

AIMS: To evaluate the effectiveness and safety of varenicline for smoking cessation among Asian adult smokers in real-world clinical practice.
METHODS: A multicentre, prospective, non-comparative, observational study conducted in China, India, Philippines and Korea. Adult smokers, willing to make a quit attempt, who reached a joint decision with the investigators to take varenicline received 1 mg twice daily (after 1-week titration) for 12 weeks. No exclusion criteria were specified. Effectiveness evaluations included smoking abstinence status for the 7-day period before the Week 12 visit and the last observed study visit, determined by verbal reporting using a nicotine use inventory and carbon monoxide levels if part of usual practice (end of study only). The safety profile of varenicline was also assessed.
RESULTS: Of 1377 subjects enrolled in the study, 1373 (99.7%) received varenicline and were evaluated for safety and effectiveness. Overall, 46.4% [95% confidence interval (CI): 43.73-49.07] of subjects successfully quit smoking by the end of the treatment phase at Week 12. When analysed by country, 57.1% (95% CI: 53.55-60.65) of subjects from China, 52.8% (95% CI: 45.21-60.25) of subjects from India, 51.0% (95% CI: 36.60-65.25) of subjects from Philippines and 20.3% (95% CI: 16.29-24.73) of subjects from Korea had quit smoking at Week 12. The most commonly reported treatment-related adverse event was nausea (11.5%).
CONCLUSIONS: This study demonstrates the effectiveness and acceptable safety profile of varenicline for smoking cessation in a real-world setting among Asian populations, with results consistent with those of varenicline randomised controlled trials.