Factor VIII antibodies: Rx

Also known as acquired Hemophillia A

• Treat bleeding and its complications
• If titer < 5 BU, try human FVIII infusions, aiming for plasma levels of 30– 50%
• If titer > 5 BU, begin with rVIIa at a dose of 90–120 μg/kg IV q 3 hours. Follow clinical response.
• If still bleeding, should use activated prothrombin complex concentrate (aPCC) or recombinant factor VIIa (rVIIa). These agents bypass Factor VIII
• Removal or eradication of inhibitors
• If associated with pregnancy, wait 4-8 weeks and follow titers
• rituximab, 375 mg/m2 q week × 4. Follow inhibitor titers. If Bethesda titers have not begun to fall by week 4, institute therapy with prednisone 1 mg/kg and cyclophosphamide, 100 mg po qd.
• If no benefit from above therapies, consider other immunosuppressive agents, including mycophenolate mofetil, cyclosporine A, azathioprine, vincristine, and 2-chlorodeoxyadenosine.