OBJECTIVES: Omalizumab is the first and yet the only highly effective biological drug that was introduced in 2002 to treat pharmacologically resistant asthma. It was approved in Russia in 2007. This is the first pharmacoeconomic evaluation of omalizumab use in addition to a maintenance therapy in patients with severe uncontrolled atopic asthma in Russia. METHODS: Thorough literature search was conducted, eleven randomized clinical trials of omalizumab were retrieved. The disease was modeled as a discrete-time Markov chain with one-week cycle with 7 states: controlled asthma, partially controlled asthma, uncontrolled asthma, non-severe exacerbation, severe exacerbation without hospitalization, severe exacerbation with hospitalization, and death. Direct (medication, laboratory tests, general practitioner visits, asthma-related hospitalization, glucocorticoid-related side effects) and indirect costs (losses of gross domestic product and social security fund payments due to temporary incapacity) were included into the model. Cost-utility and cost-effectiveness analyses were implemented based on Markov chains. Model horizons were 2 and 5 years. RESULTS: Cost-utility analisis showed that “omalizumab plus standard therapy” strategy is economically feasible in patients 18 years old and older with an increased rate of annual hospitalization (≥4) who require oral corticosteroid maintenance and an average dose of omalizumab 300 mg/month (incremental cost-utility ratio is 1,139,767 rubles/QALY for 5 year horizon, which is less then societal willingness-to-pay threshold that is 1,341,308 rubles). Cost-effectiveness analysis of decrease in hospitalization rate found that additional 57,287 rubles should be spent to prevent one hospitalization in 5 years (the cost of one hospitalization is estimated to be 31,059 rubles in average). CONCLUSIONS: Although being clinically highly effective, omalizumab has high cost that limits its pharmacoeconomical usefulness to severe patients with an increased rate of annual hospitalization (≥4) who require no more than 300 mg/month of omalizumab in average. Price reduction might significantly increase the proportion of economically eligible patients.