Chronic pain syndrome (CPS) is a complex, hard to treat polyetiological condition. While there is a wide array of possible causes for CPS, it is most important in oncological context, since within oncological setting it may be induced both by the tumor itself and by the treatment modalities used against it. Analgesic therapy is, according to WHO, the primary method of managing CPS, and is effective in approximately 90% of cases. However, patients requiring strong opioids for pain management (III step of WHO’s “analgesic ladder”) face a number of complications associated with adverse events (AE), such as inhibition of respiratory control center, nausea, vomiting, and constipation. While constipation and vomiting are themselves amenable to therapeutic management, they can both significantly reduce quality of life and even require alteration of analgesic medication regime, thus potentially compromising the management of chronic pain. This has necessitated the creation of painkiller medication that would have a more favorable gastrointestinal AE profile while maintaining analgesic efficacy, such as fentanyl transdermal delivery systems (TDS) and oral formulations combining oxycodone and naloxone. The pharmacoeconomic comparison of these two medications in order to determine which of them is more economically rational within context of Russian healthcare is thus justified, and is the subject of this research effort. Aim. To perform evaluation of pharmacoeconomic (PHe) properties of combined naloxone/oxycodone formulation (Targin®) compared to fentanyl TDS (Fendivia®) in Russian oncological patients with CPS. Methodology. This PHe is conducted perspective of public health organizations of the RF at federal and national levels. The modelling horizon was 25 weeks. Comparator drugs were Targin® and Fendivia®. Randomized controlled clinical trials investigating safety and efficacy of these drugs were used as data source on safety and efficacy. A Markov model was constructed in order to estimate healthcare costs and patients outcomes. Each simulated patient group contained 100 patients. Retention of patients with adequate pain management in main treatment regime without dose increase was used as efficacy criterion, since this surrogate endpoint is most clinically relevant, reflecting ability of a given modelled treatment regimen to control chronic pain. These modelling results were used to perform the following types of pharmacoeconomic analysis: carrying out cost-effectiveness analysis (CEA), budget impact analysis (BIA), and evaluation of pharmacoeconomic expediency based on willingness-to-pay ratio (WTP). Result. Naloxone/oxycodone formulation dominates in CEA analysis (direct costs were 2,091 mln. rub. for naloxone/ oxycodone versus 3,747 mln. rub. for fentanyl TDS). The CER indicator for oxycodone/naloxone was 51 218 rub., while fentanyl TDS had CER of 317 409 rub. BIA revealed considerable budgetary burden reduction for oxycodone/naloxone, which was due to considerable reduction of GDP losses and expenses associated with disability and loss of working capacity. The resultant economy of government funds reached 44%. According to PHe analysis, both drugs are attractive for purposes of drug reimbursement system, but oxycodone/naloxone is dominant due to WTP/CER indicator of 32,1 (fentanyl TDS had WTP/CER of 5,1). Sensitivity analysis confirmed the robustness of these findings - CEA and BIA results remained stable even in case of 25% oxycodone/ naloxone price increase. Conclusion. Oxycodone/naloxone combination has been determined to be most pharmacoeconomically attractive due to higher efficiency of healthcare spending (due to domination in terms of CER) and reduction of GDP losses associated with complete disability which resulted in government budgetary savings of up to 44%.