OBJECTIVES: Assessing the  adverse events costs of comparable regimens (sunitinib vs bevacizumab) in context of budget impact analysis in Croatian setting. METHODS: Authors have assessed costs and outcomes of bevacizumab and sunitinib via systematic review, performed in January 2011. Survival rates, incidence and prevalence was assessed via Croatian National Cancer Registry, and the model was verified with Monte Carlo simulations. Direct drug, adverse events and treatment costs were calculated in kuna/per patient yearly according to price listings of National Institute for Health Insurance. Local data was verified with structured interviews gathered with Croatian oncologists (N=6) involved in this indication in their daily practice. Focus of the analysis was the drug cost and the adverse events treatment cost. RESULTS: Sunitinib has showed costly side effects such as neutropenia, trombocitopenia, hypothiroidism and cardiovascular complications. The cost of adverse events (aforementioned) for sunitinib per patient yearly is 3.904 HRK (535 EUR), whereas for bevacizumab is 1.404 HRK (192 EUR). Bevacizumab demonstrated significantly lower adverse events costs than sunitinib. Overall budget impact (from payers perspective) when bevacizumab is introduced equals -29.753,52 HRK (-4075 EUR) of savings yearly per patient. CONCLUSIONS: At current costs, head to head drug price comparison demonstrates that bevacizumab is less costly, demonstrating dominant ability to reduce costs due to less frequent and less costly adverse events, whereas in budget impact context introducing bevacizumab brings savings.