We present results from randomized comparative trial that was carried out in 10 medical centers of Russia. During 6 months 170 outpatients were observed. 68 from them were prescribed beclometason dipropionat along (group 1), 57 – beclomethasone dipropionate in a combination with oral theophylline (group 2) and 65 – fluticasone / salmeterol (group 3). Cost-effectiveness ratio in the main end points («amount of symptom-free days», «amount of days with the increment of the Peak Expiratory Flow Rate)», «amount of weeks of successful treatment») were lower in group 2 independently of the severity of asthma (cost of treatment included cost of drugs and physician visits). Analyzing the increment of ²cost-effectiveness² ratio severe asthma each additional ²symptom-free² day in group 3 in comparison with group 2 costed just 203,43 rubles, day with ²the increment of PEF² 252,67 rubles in comparison with group 1 and 246,15 rubles in comparison with group 2. Additional ²week of successful treatment² when fluticason / salmeterol was used in comparison with combined therapy costed 1583,17 rubles. In conclusion administration of fluticason / salmeterol is the most efficient in severe asthma according to the indicant of increment costs.