OBJECTIVES: To perform economical evaluation of etravirine (ETR) in treatment-experienced HIV-1-infected patients in Russian health care system. METHODS: The modeled study was performed. Multicenter randomized studies DUET 1 and 2 were used as a basis for the model. Cost-effectiveness of ETR compared to placebo, both given with a background regimen (BR) of nucleoside reverse transcriptase inhibitors, darunavir/ritonavir  and optional enfuvirtide, was assessed. Costs of antiretroviral therapy for 24 weeks were calculated from the point of Russian health care system view. Proportion of patients receiving different drugs and dosing regimen were extracted from DUET 1 and 2 trials. Effect was measured in proportion of patients with viral load less than 50 copies/ml. Limitation of the model was that emtricitabine and tenofovir used in BR in both groups have no market authorization in Russia and were excluded from the model. Similar proportion of patients in both groups received these drugs, thus this limitation did not influence the incremental  cost-effectiveness ratio (ICER). One-way sensitivity analysis was performed. RESULTS: According to DUET studies ETR was  much more effective than placebo (59 vs 41% patients achieved viral load < 50 copies/ml, p <0,001 ), while cost of treatment (without emtricitabine and tenofovir) was more for ETR than placebo group (difference in cost 4247,36 USD). Incremental CER was 20 360,90 USD for one patient with viral load < 50 copies/ml (16 462,65—41 640,81 USD in sensitivity analysis). Cost of one patient with achieved viral load < 50 copies/ml  was lower for ETR group. CONCLUSIONS: According to the model ETR seems to be much more effective than placebo with affordable CER incremental ratio. Evaluation of ETR treatment cost-effectiveness in common practice in Russian health care is needed.