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

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

The study start on January 18, 2017. The Severe(FⅧ<1%) and moderate hemophilia A (FⅧ1%～5%)children with high titer inhibitor(historical peak inhibitor titer≥5BU ) combining with poor ITI risk(s) were enrolled. The low-dose ITI was alone or combined with immunosuppression.

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.

The low-dose ITI was Coagulation Factor VIII (50IU/kg, every other day) alone or combined with prednisone (2mg Kg-1/day, one month, then taper in three months) depending on the tendency of inhibitor, and Rituximab (375mg/square meter every week for 4 weeks) when the inhibitor titer ≥40BU/ml before or during ITI.Inhibitor and hemorrhage should be retested and recorded periodically.

Inclusion Criteria: Males from 1 to 14 years old severe or moderate hemophilia A; inhibitors positive before ITI started. Exclusion Criteria: Females <1 or >14 years old hemophilia B or mild haemophilia A; inhibitor negative before ITI started.