Background:
The interruption of smoking is the best way to prevent diseases. The perspective of using genetic markers, which indicate more effectiveness to the tobacco treatment, can change this scenario bringing more objectivity in the treatment of this disease. Pharmacogenomics of smoking treatment was evaluated in over 1000 patients in our Smoking Cessation Center between 2009 to 2014 period. We found the association of the CHRNA4 rs1044396 polymorphism with varenicline therapy. Patients with CT or TT genotypes had a higher chance of success than CC(OR = 1.67; CI = 1.10 -2.53; p = 0.02). We also found the association of the CYP2B6 rs2279343 polymorphism with bupropion therapy. Patients with AA genotype had a higher chance of success compared to AG or GG genotypes (OR = 1.92; IC = 1.08-3.42; p = 0.03). It was a retrospective study, so we started in 2015 a prospective study to identify the frequency of these polymorphisms in smokers who looks for smoking cessation programs.

Methods:
We collected data and blood sample from 127 smokers (october 2015 to december 2016) to investigate Bupropion CYP2B6 rs2279343 and Varenicline CHRNA4 rs1044396 polimorphisms.

Results:
The average of age was 50 + 9 (20 -74 years), 80% caucasian, 14% afro descend, 6% yellow. The polymorphism favoring Bupropion (AA) was found in 58.2% (74) and favoring to varenicline (CT and TT) in 70% of the sample (89). Important to say that 42 participant had both polymorphisms favoring to varenicline and to Bupropion (33%).Only 12 smokers presented both unfavorable polymorphisms to any of these drugs.

Conclusions:
The prospect of choosing the drug based on this finding may have a relevant economic impact, eventhough trials shows that varenicline is more efective than bupropion, Bupropion is cheaper than varenicline. We already started a randomized trial to test the cost-effectiveness of this hypothesis.