Hemophilia

Inclusion Criteria

- Severe hemophilia A (FVIII:C </=1%)
 - No history of FVIII inhibitor formation and no current evidence of inhibitor antibody (Bethesda Assay < 0.6 BU)
 - Elective major surgery requiring at least 6 days of rFVIII-FS therapy- Subjects should have been previously treated with FVIII concentrates for at least 150 exposure days. Previous treatment could have been with any type of rFVIII or with plasma-derived FVIII concentrate or cryoprecipitate

Exclusion Criteria

- Abnormal renal function (serum creatinine >1.3 mg/dL) 
 - Any treatments, which may change the clearance of FVIII (dialysis, plasmaexchange)
 - Anemia (hemoglobin <11 g/dL)- Known AIDS (HIV seropositive patients may be enrolled) 
 - Active liver disease (transaminases > 5 times the upper limit of normal)
 - History of severe reaction to FVIII concentrates
 - Interferon treatment within the last 3 months 
 - Thrombocytopenia (< 100,000 platelets/mm3) or other known hematological/bleeding problems other than hemophilia A 
 - Intake of other investigational drugs within 1 month prior to study entry
 - Need for pre-medication for FVIII infusions (e.g. antihistamines)
 - Diastolic blood pressure >100 mm/Hg, which could not be controlled with antihypertensive medications