Extended (6-Week) Varenicline Preloading: Does it Facilitate Smoking Reduction and Cessation?
Status:
Completed
Trial end date:
2018-06-28
Target enrollment:
Participant gender:
Summary
SUMMARY Rationale: Worldwide, cigarette smoking carries a high mortality. Since the available
cessation programs are not effective for all smokers, new strategies are necessary for
tobacco control.
Primary objective: To investigate whether a 6-week varenicline preloading facilitates smoking
reduction and cessation compared with the standard varenicline treatment schedule.
Design: Parallel group, double-blind, randomised controlled clinical trial. Participants:
Smokers of both sexes from the general population. Methods: Participants will be randomized
into two groups of treatment. Subjects in Group A will receive varenicline for six weeks
while those in group B will receive placebo for 5 weeks and varenicline for 1 week. During
this phase, subjects in both groups will be asked to reduce cigarette smoking by 50 percent.
At week 6 all participants will be instructed to stop smoking before receiving 12 weeks of
varenicline treatment. Visits will be arranged at randomization, week 4, week 6 (Quit day
(QD)) and at week 1, 6, 12, and 24 after QD.
Measurements: These will include vital signs, smoking history, spirometry, expired CO,
salivary cotinine, nicotine dependence, and withdrawal symptoms. Primary outcome is
continuous abstinence at 6 months.
Sample size: For an estimated difference of quit rates of 15% at 24 weeks (30% for group A
vs. 15% for group B) 121 subjects per group are needed (Total = 242 subjects).
Statistical analysis: T tests (rational variables) and x2 test or Fisher's exact test
(nominal variables) will be used as appropriate.
Expected benefits: This study might contribute to optimize the current use of varenicline.