Achieving Hemostasis If titer < 5 BU, try human FVIII infusions, aiming for plasma levels of 30–50%, if possible. Check FVIII activity level 30 min after FVIII bolus. Begin with dose of 100 units/kg if patient having significant bleeding. If titer > 5 BU, begin with rVIIa at a dose of 90–120 μg/kg IV q 3 hours. Follow clinical response. If response is inadequate, consider therapy with FEIBA, 75–100 units/kg iv q 8–12 hrs, or consider high dose rVIIa at 270 μg/kg, followed by 90–120 μg q 3 hrs. If patient fails to respond to bypassing agents, try treatment plasmapheresis or immunoadsorption with staphylococcal Protein A column, followed by FVIII replacement therapy.
Inhibitor Eradication If inhibitor developed in association with childbirth or treatment with a suspect medication, follow titers and wait 4–8 weeks. Otherwise, begin therapy with 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.
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