Pfizer and GlaxoSmithKline.

Pfizer.

Abstinence rates decreased with increasing dependence scores. There was no interaction between treatment and baseline FTND or HSI score, suggesting that they have no effect on the efficacy of varenicline versus placebo. These results also suggest that the HSI may be as effective at predicting smoking cessation outcome as the whole FTND questionnaire.

There was no significant increase in overall psychiatric disorders, other than sleep disorders and disturbances, in varenicline-treated subjects in this sample of smokers without current psychiatric disorders. Ongoing studies are testing the use of varenicline in psychiatric patients.

Importance Some cigarette smokers may not be ready to quit immediately but may be willing to reduce cigarette consumption with the goal of quitting. Objective To determine efficacy and safety of varenicline for increasing smoking abstinence rates through smoking reduction. Design, Setting, and Participants Randomized, blinded, placebo-controlled, multinational clinical trial with a 24-week treatment period and 28-week follow-up conducted between July 2011 and July 2013 at 61 centers in 10 countries. 1510 cigarette smokers not willing or able to quit smoking within the next month but willing to reduce smoking and make a quit attempt within the next 3 months recruited through advertising. Interventions Twenty-four weeks of varenicline titrated to 1 mg twice daily or placebo with reduction target of ≥ 50% in number of cigarettes smoked by 4 weeks and ≥ 75% by 8 weeks and a quit attempt by 12 weeks. Main Outcome Measures Primary efficacy endpoint was carbon monoxide (CO)-confirmed self-reported abstinence during weeks 15-24. Secondary outcomes were CO-confirmed self-reported abstinence rate for weeks 21-24 and weeks 21-52. Results The varenicline group (N = 760) had significantly higher continuous abstinence rates during weeks 15-24 versus placebo (N = 750) (32.1% vs 6.9%; risk difference (RD) 25.2%; 95% CI 21.4%, 29.0%; relative risk (RR) = 4.6; 95% CI 3.5, 6.1). The varenicline group had significantly higher continuous abstinence rates versus placebo during weeks 21-24 (37.8% vs 12.5%; RD 25.2%; 95 CI 21.1%, 29.4%; RR 3.0; 95% CI 2.4, 3.7) and weeks 21-52 (27.0% vs 9.9%; RD 17.1%; 95% CI 13.3%, 20.9%; RR 2.7; 95% CI 2.1, 3.5). Serious adverse events occurred in 3.7% and 2.2% of the varenicline and placebo groups, respectively (P = 0.07). Conclusions and Relevance Among cigarette smokers not willing or able to quit within the next month but willing to reduce cigarette consumption and make a quit attempt in the next 3 months, use of varenicline for 24 weeks compared with placebo significantly increased smoking cessation rates through 6 months of follow up. Varenicline offers a treatment option for smokers whose needs are not addressed by clinical guidelines recommending abrupt smoking cessation. Trial Registration www.clinicaltrials.gov (NCT01370356): https://clinicaltrials.gov/ct2/results?term=NCT01370356&Search=Search