A multicentre, randomized, double-blind, placebo-controlled, 1-year study of bupropion SR for smoking cessation.

BACKGROUND: Bupropion sustained release (bupropion SR) has been shown to increase smoking cessation success rates in the US studies.

OBJECTIVE: To determine whether bupropion SR, in combination with counselling, is effective for smoking cessation in a multi-country study.

METHODS: This randomized, double-blind, placebo-controlled trial enrolled 707 smokers. A total of 527 received bupropion SR 300 mg daily for 7 weeks and 180 received placebo. A total of 11 clinic visits and 10 telephone contacts were scheduled, during the course of 1 year. Seven-week and 12-month abstinence rates were the study outcomes.

RESULTS: Both continuous and weekly point prevalence smoking abstinence rates were significantly higher in the bupropion SR group compared with placebo. The continuous abstinence rate from weeks 4 to 7 was 46% in the bupropion SR group compared with 23% in the placebo group [odds ratio (OR) = 2.82; 95% confidence interval (CI) 1.89-4.28; P < 0.001). At month 12, the continuous abstinence rates were 21% for the bupropion SR group and 11% for the placebo group (OR = 2.19; 95% CI 1.29-3.86, P = 0.002). For most nicotine-withdrawal symptoms small changes were measured. Adverse events were higher for the bupropion SR group compared with placebo (insomnia 24% vs. 15%; dry mouth 13% vs. 5%).

CONCLUSION: Bupropion SR in combination with counselling increased the abstinence rate compared with placebo, and was well tolerated.