Safety and Effectiveness of Varenicline in Korean Smokers: A Nationwide Post-Marketing Surveillance Study.

PURPOSE

Varenicline has demonstrated its safety and efficacy in Western studies including <3% of Asian participants. This prospective multi-center observational study investigated the safety and effectiveness of varenicline in Korean smokers.

PATIENTS AND METHODS

Smokers prescribed varenicline for the first time were enrolled from 252 medical institutions. Investigators recorded and graded all adverse events (AEs). To assess the effectiveness of varenicline, the 7-day point prevalence (PP) of smoking cessation was evaluated at the four visits during the 12-week treatment course. Rates of AE incidence and smoking cessation were analyzed using Chi-squared test or Fisher's exact test. This study is registered with ClinicalTrials.gov, number NCT00483002.

RESULTS

A total of 3719 and 3700 study subjects were included in the safety and effectiveness analyses, respectively. Overall, 346 (9.3%) subjects experienced 471 AEs: 358 mild, 97 moderate, 9 severe, and 7 serious. The most frequent AEs were nausea (5.1%), dyspepsia (0.8%), abnormal dreams (0.8%), insomnia (0.8%), and headache (0.7%). Among the subjects with AEs, 73 subjects discontinued treatment, of which 68 were due to AE occurrence. The 7-day PP of smoking cessation at weeks 1-2, 3-6, 7-10, and ≥ week 11 were 51.7% (387/749), 59.6% (1740/2922), 73.3% (1114/1520), and 77.0% (1116/1449), respectively (p for trend = 0.023). Comorbidities and allergies were associated with a higher incidence of AEs and lower smoking cessation rate (p < 0.05). Younger subjects, infrequent alcohol drinkers, and lighter smokers showed a higher smoking cessation rate (p < 0.05).

CONCLUSION

Varenicline in adult Korean smokers was well tolerated and effective as a smoking cessation aid in routine clinical practice.