Cost-Utility Analysis of Varenicline, an Oral Smoking-Cessation Drug, in Japan

Abstract

To conduct a cost-utility analysis of two 12-week smoking-cessation interventions in Japan: smoking-cessation counselling by a physician compared with use of varenicline, an oral smoking-cessation drug, in addition to counselling. A Markov model was constructed to analyse lifetime medical costs and QALYs from the perspective of the healthcare payer. The cycle length was 5 years. Both costs and QALYs were discounted at 3% annually. The cohort of smokers was classified by sex and age, and we assumed that smokers started smoking at the age of 20 years and received smoking-cessation therapy at the ages of 30, 40, 50, 60 or 70 years (five separate models were run). The healthcare costs and QALYs were calculated throughout the term until the age of 90 years. In the base-case analysis, success rates of varenicline plus counselling and counselling alone were assumed to be 37.9% and 25.5%, respectively, in male smokers, and 22.2% and 16.1%, respectively, in female smokers, based on a randomized controlled trial conducted in Japan. Both univariate and probabilistic sensitivity analyses were conducted. Prescribed varenicline was shown to be more effective and less costly than smoking-cessation counselling alone. Varenicline would save direct medical costs of Japanese Yen (yen)43 846 ($US381; $US1 = yen115; Oct 2007) and generate an increase of 0.094 QALYs in male smokers. In females the incremental cost-effectiveness ratio was yen346 143 per QALY gained. Varenicline is estimated to save yen23.7 billion ($US206 million) of the medical costs for tobacco-associated diseases for the whole population. Overall savings are yen9.5 billion. Sensitivity analyses suggested the robustness of the results. As with any data of this nature, there is some uncertainty in the results and further research is warranted. However, based on the results of this pharmacoeconomic evaluation, varenicline, the first non-nicotine, oral treatment developed for smoking cessation, appears to be cost effective and may contribute to future medical cost savings in Japan.