OBJECTIVES: Immune thrombocytopenia (ITP) is characterized by isolated thrombocytopenia with no underlying cause. It manifests clinically as mucocutaneous bleeding caused by decreased platelets. Recently, two thrombopoietin receptor-agonists have emerged as an important therapeutic options: romiplostim and eltrombopag. Since these medications have different mode of administration, safety and efficacy profiles, the present study was carried out in an attempt to investigate which drug would be more cost-effective in the Brazilian setting. The objective was to perform an economic analysis evaluating the cost per response of romiplostim versus eltrombopag in adult patients with chronic ITP and refractory to other treatments as corticosteroids and immunoglobulins in Brazil healthcare private system. METHODS: Two economic analyses were performed in order to study the use of romiplostim and eltrombopag for the treatment of adults with chronic refractory ITP, based on annual treatment costs and cost per response. The average body weight adopted was 74,6 kg. Efficacy data were obtained from the product inserts, as well as from scientific publications. In cost per response, it was considered a 6-month analysis, which corresponds to the overall platelet response in clinical trials. The outcome of these trials was the global response to treatment. The cost of each drug presentation were based on ex-factory price (VAT 18%) and obtained from the official price list (CMED; April, 2014). RESULTS: The cost of treatment with romiplostim showed an annual saving of R$7,724 over eltrombopag within the payer perspective, which may be further improved if we assume that drug-food interactions of eltrombopag in some patients lead to reduced medication adherence and loss of response. The cost per response with romiplostim was 26% lower than with eltrombopag. CONCLUSIONS: Romiplostim was more cost-effective than eltrombopag for the treatment of chronic refractory ITP in adult patients and may represent savings to the Brazilian health system.