Study to Evaluate the Safety, Pharmacokinetics and Efficacy of Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) in Subjects With Severe Hemophilia A

• Clinically notable changes from baseline in physical examinations, vital signs, lab values, and incidence of AEs and inhibitor development [ Time Frame: 156 weeks ] [ Designated as safety issue: Yes ]
  
• Annual number of bleeding episodes (spontaneous and traumatic) [ Time Frame: 156 weeks ] [ Designated as safety issue: Yes ]
  

• Total annualized rFVIIIFc consumption per subject [ Time Frame: 156 weeks ] [ Designated as safety issue: Yes ]
  
• Evaluation of PK parameter estimates of rFVIIIFc and rFVIII [ Time Frame: 156 weeks ] [ Designated as safety issue: Yes ]
  
• Evaluation of subject's response to treatment [ Time Frame: 156 weeks ] [ Designated as safety issue: Yes ]
  
• To evaluate the efficacy of rFVIIIFc used in a surgical subgroup [ Time Frame: 156 weeks ] [ Designated as safety issue: Yes ]
  

The current hemophilia standard of care for the prevention of bleeds and arthropathy is to maintain FVIII activity level above 1%. Due to the short half-life of the current FVIII products, prophylaxis therapy will require injection of 2-3 times per week or every other day. Treatment usually involves intravenous access, an invasive procedure, especially difficult in children. Episodic treatment will involve 1-3 injections to treat bleeding episodes, depending on the severity of the hemorrhage. Severe hemophilia patients will treat prophylactically with the long-lasting recombinant factor VIII Fc fusion protein (rFVIIIFc) in an interval to maintain FVIII activity level above 1%. Any bleeding episodes will be reported. The response to treatment will also be recorded to access the effectiveness of the rFVIIIFc.