Low dose vs standard dose varenicline for smoking cessation

Background: Varenicline is used at a standard dose as a first line pharmacotherapy in smoking cessation, as proposed by international guidelines. Aim: To assess the short and long term abstinence rate from smoking with low dose of varenicline in the second and third month of treatment. Design: A retrospective non-randomized clinical trial was conducted at a stop-smoking center of University Hospital of Heraklion, Crete, Greece during economic crisis, from January 1, 2016 to December 29, 2016. Participants were 143 smokers (> 30 pack years) with mean age of 48, 64% men and 36% women. Method: All participants received standard dose varenicline for 4 weeks (0.5mg for 3 days, 0.5mg twice daily for 3 days, and 1mg twice daily from 8th to 28th day). 78 were lost to follow up and 65 were finally analyzed. At 29th day 31 participants received low dose (1mg once daily) and 34 received standard dose (1mg twice daily). Main Outcome: Compliance to treatment (exhaled carbn monoxide Results: For weeks 1 through 6, the 6-week continuous abstinence rates were 91,2% for low dose varenicline vs 51.6% for standard dose varenicline (p=0.004). Abstinence rate at 2 years was 31.6% for low dose varenicline vs 38,9% for standard dose (p=0.388). Patients attending the 4th and 5th visits had higher abstinence rate at 2 years (p=0.005). Conclusion: Low dose of varenicline is non inferior to standard dose both at the short term and long term period. We also showed that the close follow up of patients results to higher abstinence rate at 2 years.