Nicotine replacement therapy is an effective treatment for nicotine-dependent smokers. However, cessation rates are modest, and preliminary studies suggest that combination therapy may be superior. We compared the efficacy of the nicotine inhaler plus nicotine patch vs nicotine inhaler plus placebo patch for smoking cessation.
A double-blind, randomized, placebo-controlled trial was conducted in 400 subjects who had smoked 10 or more cigarettes per day for 3 years or longer. Group 1 (n = 200) received the nicotine inhaler plus nicotine patch (delivering 15 mg of nicotine per 16 hours) for 6 weeks, then inhaler plus placebo patch for 6 weeks, then inhaler alone for 14 weeks. Group 2 (n = 200) received the nicotine inhaler plus placebo patch for 12 weeks, then inhaler for 14 weeks. Inhaler was used at a rate of 6 to 12 cartridges per day ad libitum for 3 months and then tapered off. Main outcome measures were complete abstinence (self-reported) and expired carbon dioxide concentration less than 10 ppm.
Group 1 vs group 2 complete abstinence rates were 60.5% and 47.5% at 6 weeks (P = .009), 42.0% and 31.0% at 12 weeks (P = .02), 25.0% and 22.5% at 6 months (P = .56), and 19.5% and 14.0% at 12 months (P = .14). One-year survival analysis showed a significant association between abstinence and treatment with nicotine inhaler plus nicotine patch (P = .04). Mean nicotine substitution at week 6 was 60.1% (group 1) and 24.6% (group 2) (P<.001). At 12 months, the frequency of respiratory symptoms in abstinent subjects fell significantly and lung function showed a trend toward improvement. The most common adverse events were throat irritation (inhaler) and itching (patch).
Treatment with the nicotine inhaler plus nicotine patch resulted in significantly higher cessation rates than inhaler plus placebo patch.