OBJECTIVES: Evaluation of cost-effectiveness and cost-utility of afatinib in patients with non-small cell lung cancer (NSCLC) with deletion in 19th exon of epidermal growth factor receptor (EGFR) gene in 1st-line therapy. METHODS: Markov modeling was implemented to simulate clinical and economical outcomes of different strategies in treatment of naïve patients with NSCLC over 18 years old based on results of randomized clinical trials LUX-Lung 3 and LUX-Lung 6. Direct medical costs were considered. The time horizon of the analysis – 10 years. Compared drugs: afatinib, erlotinib, gefitinib and combination cisplatin/pemetrexed. Results were expressed in terms of quality-adjusted life years (QALY), life years (LY) gained and ICER (QALY). RESULTS: Afatinib used as 1st-line treatment in patients with NSCLC with Del 19 mutation increased quality-adjusted life years (QALY) by 0,354, 0,665 and 0,670 QALY and overall survival by 0,61, 0,99 and 0,95 years in comparison with erlotinib, gefitinib and combination cisplatin/pemetrexed respectively. The total costs of therapy for compared drugs were: afatinib – 1 917 425 rub., erlotinib – 1 544 852 rub., gefitinib – 1 205 353 rub. and cisplatin/pemetrexed – 1 203 865 rub. The ICERs were 1 052 934, 1 067 116 и 1 064 708 rubles in comparison with erlotinib, gefitinib and combination cisplatin/ pemetrexed respectively per QALY. CONCLUSIONS: Afatinib was demonstrated to have the highest efficiency in terms of overall survival and QALY. Direct costs associated with afatinib were the highest because of afatinib superior efficiency. Afatinib was shown to be the cost-effective strategy in 1st-line treatment of metastatic NSCLC with Del 19 gene mutation as willingness to pay threshold (1 455 741,77 rubles) was not exceeded.