Inclusion Criteria:

• Males aged 18 to 50 years
• Subjects with severe hemophilia A (<1% FVIII:C) as confirmed by the central lab from a sample obtained at least 96 hours after FVIII administration wash-out. Allow for the inclusion of a maximum of 10% (n=8) of patients with 1-2% FVIII:C baseline levels as long as they exhibit clinical severity and comply with all other inclusion criteria.
• Subjects with at least 150 prior exposure days with any FVIII
• Subjects who have been on episodic treatment and no known regular prophylaxis treatment for more than 12 consecutive months in the previous 5 years
• Subjects with at least 6 bleeding events and/or treatments in the previous 6 months prior to study entry which are documented and available in the subjects medical records, and a maximum of 12.
• Subjects with no measurable inhibitor activity by Nijmegen-modified Bethesda assay (>0.6BU is considered positive) in two consecutive samples and absence of clinical signs or symptoms of decreased response to rFVIII administration. (First negative sample can be historical if obtained within 3 months prior to screening. Second sample confirmatory must in all cases be performed by the study reference lab using the Nijmegen test. If a first recent sample is not available, then 2 negative samples by the study reference lab at least 1 week apart should be obtained). Prior to collecting samples for inhibitors the subject must not have received FVIII for a minimum of 96 hours or 4 days. For Nijmegen negative (but measurable) values between ≥ 0.3 and < 0.6BU, a FVIII recovery determination over 2% /IU/kg infused will be required.
• Subjects with no history of FVIII inhibitor antibody formation ≥0.6BU by Nijmegen- modified Bethesda assay but with a maximum historical titer of 1.0BU on no more than one occasion with the Classical Bethesda assay but at least three successive negative [<0.6BU]determinations thereafter are also eligible.
• Subjects who complete an EPD device training and demonstrate the ability to correctly use it.
• Documented, signed, dated informed consent obtained prior to any study specific procedures being performed.

Exclusion Criteria:

• Subjects with any other bleeding disease besides hemophilia A (i.e. von Willebrand disease)
• Subjects with thrombocytopenia (platelets < 100,000/mm3)
• Subjects with abnormal renal function (Cockcroft-Gault Creatinine Clearance value of 60 mL/min or lower)
• Subjects with active hepatic disease (AST or ALT > 5xULN)
• Subjects on treatment with immunomodulatory agents within the last 3 months prior to study entry or during the study (the following drugs are however allowed: interferon-a; treatment for HCV, HAART therapy for HIV and /or a total of two courses of pulse treatment with steroids for a maximum of 7 days at 1mg/kg or less)
• Subjects with an absolute CD4 lymphocyte cell count < 200 cells/mm3 (due to HIV, HCV or another suspected medical condition)
• Subjects with known hypersensitivity to rFVIII, mouse or hamster proteins
• Subjects who are receiving or had received other experimental drugs within 1 month prior to study entry
• Subjects who require any pre-medication to tolerate FVIII injections (e.g. anti-histamines)
• Subjects who are unwilling to comply with study visits or either of the possible treatment regimens
• Subjects who have a planned orthopedic intervention to be performed during the study that may substantially affect bleeding (e.g. surgical or chemical or radiological synovectomy)
• Subjects who are not suitable for participation in this study for any reason, according to the Investigator