Low-dose ITI Strategy for Children in Hemophilia A With High-titer Inhibitor and Poor ITI Risk in China

Poor risk(s) includes:①peak historical inhibitor titer≥200BU ②inhibitor titer≥10BU before ITI initiation ③peak inhibitor titer during ITI≥200BU ④time to titer decline to\<10BU before ITI≥24 months ⑤age≥8 years at start of ITI ⑥ITI initiated ≥5 years after inhibitor diagnosis ⑦interruptions in ITI≥2 weeks in duration. The low-dose ITI strategy consist of FⅧ（25-50IU/kg）alone or combining with immunosuppression: prednisone and Rituximab when the inhibitor titer ≥40BU ml/ml before or during ITI.