• Complete success is the abolition of the inhibitor to < 0.6 BU, within 33 months of ITI with a factor VIII recovery ≥ 66% and half-life ≥ 6 hours, measured after a 72-hour washout period. [ Time Frame: 3 years ] [ Designated as safety issue: Yes ]
  

• Absence of relapse up to 12 months after achievement of tolerance. [ Time Frame: Up to 45 months ] [ Designated as safety issue: Yes ]
  
• Time to achieve success- either partial or complete. [ Time Frame: Up to 45 months ] [ Designated as safety issue: Yes ]
  
• Safety - assessment of adverse events through treatment and compliance with prolonged regimen. [ Time Frame: Up to 45 months ] [ Designated as safety issue: Yes ]
  
• Cost of care. [ Time Frame: Up to 45 months ] [ Designated as safety issue: Yes ]
  

Drug: VWF/FVIII concentrates
200 IU/Kg by one or two bolus injections daily. After successful confirmation the dose will be tailed off progressively until discontinuation. Patients will be treated with a VWF/FVIII concentrates according to physician/patients preference.
Other Names:
• Beriate P
• Koate-DVI
• Emoclot DI
• Factane
• 8Y
• Optivate
• Alphanate
• Fahndi
• Haemate P
• Humate P
• Haemoctine SDH

The presence of Factor VIII (FVIII) inhibitor prevents FVIII infusions from working properly and makes treatment of bleeding episodes very difficult. Having an inhibitor is a serious and life-threatening complication in patients with Hemophilia. The usual treatment of patients with FVIII inhibitors involves what is called "immune tolerance induction" (ITI). Immune Tolerance means that the body can accept infused FVIII and that FVIII is again effective in controlling bleeds. ITI involves giving high doses of FVIII regularly until the inhibitor disappears. This treatment is not always effective. The inhibitor persists in about 1 in 5 patients who undergo ITI.

There are 2 types of FVIII concentrates: FVIII concentrates derived from human plasma, which contain VWF, and concentrates of FVIII without VWF. Both types of concentrates are commonly used to induce immune tolerance in patients with Hemophilia A. Retrospective studies on subjects who were treated with VWF containing Factor VIII concentrates after failing ITI with pure factor VIII concentrates, have shown that tolerance can be achieved in a large percentage of patients. This study will access prospectively whether treatment with a FVIII concentrate containing VWF given at a high dose (200 units per kilogram) daily for up to 33 months is able to induce immune tolerance after previous attempts with concentrates containing only FVIII have failed.