OBJECTIVES Haemophilia A is a hereditary genetic disorder with a relatively high burden of disease from the perspective of both society and the individual patient. Kogenate FS is a second-generation full-length recombinant factor VIII (FVIII), produced without the addition of human albumin during formulation. It shows lower incidence of inhibitors compared with other recombinant factor VIII products, which has an impact on economic evaluation because the haemophilia patients with inhibitors have to be treated with a significantly higher dosage or expensive bypassing agents. The main objective of this study is to conduct economic evaluation of Kogenate FS compared with Recombinate in haemophilia A patients in Korea. METHODS A cost-minimization analysis was performed under the assumption that Kogenate FS and Recombinate were clinically equivalent for treating bleeding episodes. A decision-analytic model was developed to estimate the lifetime costs by reflecting each different treatment strategies for haemophilia A patients with inhibitors or not. If patients had inhibitors, it was ramified according to the inhibitor titres into one of three pathways: <5BU, 5-10BU, and >10BU. The analysis was conducted based on the societal perspective, and costs were discounted at 5% annually. Sensitivity analyses were performed on crucial parameters. RESULTS Incidence of inhibitor for Kogenate FS and Recombinate were 8.113% and 16.9% respectively. Using the base case analysis, the expected cost for Kogenate FS was US$1,979,133 compared with $2,382,332 for Recombinate. So, Kogenate FS is $403,199 lower than Recombinate during lifetime. The differences were mainly due to the higher inhibitor treatment costs. One-way sensitivity analysis revealed stable across included parameters. CONCLUSIONS This cost minimization study identified that treatment of Kogenate FS appears to save costs compared with treatment of Recombinate. By initiating and continuing Kogenate FS treatment, the economic burden associated with Haemophilia A can be reduced under Korean health care system.