Regular prophylaxis with activated prothrombin complex concentrates in pediatric hemophilia.

Background: Regular prophylaxis with activated prothrombin complex concentrates (aPCCs) is effective in adult patients with hemophilia with inhibitors; however, data in children are scarce.

Methods: This was a single-center retrospective study at Saitama Children's Medical Center. Patients with severe and moderate hemophilia with inhibitors aged <15 years at the start of aPCCs prophylaxis were included. Medical records were retrospectively reviewed.

Results: We treated nine pediatric patients with hemophilia with inhibitors (median age, 1.9 years; age range, 1.3-12.9 years; inhibitor titers before treatment with aPCCs, 5.9-69 BU/mL) using prophylactic aPCCs (doses, 50-100 U/kg; 2-3 times/week). The median prophylactic period was 13 months (range: 5-31 months). The median annualized bleeding rate (ABR) during prophylactic treatment with aPCCs was 2 (range, 0-17). In four patients, ABR was reduced by 19%-100% with prophylactic aPCCs compared to on-demand aPCCs. An adverse effect of treatment was that a patient with hemophilia B developed nephrotic syndrome 34 months after starting regular prophylaxis with aPCCs.

Conclusions: Regular prophylactic aPCCs reduced the ABR even in younger children with hemophilia A and B. Serious adverse events include nephrotic syndrome, which requires caution.