OBJECTIVES: To estimate the budget impact of adding rFVIIIFc to a managed care organization (MCO) formulary in the United States METHODS: A model was developed in Microsoft® Excel 2010 to evaluate the budget impact of including rFVIIIFc on formularies along with other recombinant FVIII (rFVIII) therapies over a 2-year time horizon. The model compared the drug-related costs of an MCO formulary containing conventional FVIII treatments with the costs of a formulary that also includes rFVIIIFc. The number of people with hemophilia A in the MCO was estimated using published prevalence data and was limited to adults with severe hemophilia A, free from FVIII inhibitors (neutralizing antibodies), receiving treatment with rFVIII therapy. It was assumed that 55% of patients receive prophylaxis therapy while the remaining 45% receive episodic therapy. Market share of rFVIIIFc was assumed to increase from 0% to 8.5% in year 1 and year 2. Medication costs were the only resource included in the budget impact model. The annual costs associated with factor replacement therapy were estimated by factor unit costs (acquisition cost) and by annual factor consumption. Annual factor consumption and bleeding rates were estimated using clinical trial and real world data. RESULTS: The estimated budget impact of adding rFVIIIFc to the formulary was associated with a budget increase of 1.4%/year for a private payer population of 1,000,000 plan members, with an estimated 21 members receiving treatment for hemophilia A. The overall impact to the budget was estimated to be $121,176 per year which corresponds to $0.01 per member per month, largely due to patients switching from episodic to prophylaxis therapy. Switching to rFVIIIFc therapy was projected to reduce the annual bleed rate by approximately 3.1 bleeds/patient/year, with an incremental cost of $1,880 per bleed avoided. CONCLUSIONS: Introduction of rFVIIIFc into MCO formularies may be associated with minimal budget impact.