Use of varenicline for as long as necessary to achieve abstinence has not been studied. The aim of this study was to test whether smokers with mild-to-moderate chronic obstructive pulmonary disease (COPD) are able to quit if they use varenicline for a sufficient length of time.

A total of 30 heavy smokers with COPD took varenicline for sufficiently long enough for smoking cessation. Smokers were allowed to smoke without a fixed quit date. The main endpoints were the time of voluntary abstinence (VA) and the continuous abstinence rate (CAR) at 12 and 18 months.

Of 28 subjects, eight subjects continued to smoke and 20 subjects stopped smoking, demonstrating a CAR up to 18 months (71%). Median time of treatment was 6 (range 3–24) and 2 (range 1–8) months for abstainers and non-abstainers, respectively, and the median time of VA for abstainers was 4 (range 1–21) months.

Use of varenicline for more than the traditional 12 recommended weeks may be a good strategy to increase the cessation rate in heavy smokers with mild COPD.