OBJECTIVES: In our study we aimed to assess and compare the cost-effectiveness of sepsis treatment with and without Activated Protein C in Hungary for the year 2002. METHODS: To calculate the average efficiency of treatment of a septic patient in ICU in Hungary we constructed a model. This model was made up of three parts. In the first part, we defined a septic patient cohort based on the age and gender distribution of all the septic cases treated in ICU in Hungary in 2001. This patient cohort entered into the second part of the model where we developed a time dependent Markov model to describe and analyse the route of Hungarian septic cases through a 28-day-long period. We defined three Markovian states: survival in ICU, leaving ICU or the hospital alive, and death in or out of ICU. Transfer probabilities were defined for each of the 28 days on the basis of data collected for all septic events treated in ICUs in Hungary in 2001. In the Activated Protein C (Xigris®) treatment arm the transfer probabilities of the above-described model was modified on the basis of results of a clinical study. In the third phase, patients’ life-long survival was modelled based on the average age-specific life expectancy of the Hungarian. Survival of the septic patients was corrected by a factor of 0.51 taken from the international literature. Efficiency was calculated from societal viewpoint. RESULTS: Average cost-effectiveness of sepsis treatment was 120,458 HUF per life years saved. In the Activated Protein C treatment arm the average cost–effectiveness was 312,085 HUF per life years saved (societal viewpoint). CONCLUSION: Incremental efficiency of Activated Protein C treatment was compared to incremental efficiency of dialysis and renal transplantation. Robustness of results was examined through a sensitivity analysis.