Background: Prophylaxis the current standard care for patients with severe hemophilia should be planned to optimize the replacement therapy and minimize bleeding. We report our single-center experience of tailored prophylaxis in children affected by hemophilia A (HA) and hemophilia B (HB).

Methods: This study was conducted on 55 patients, under 15 years, with HA (PWHA, n: 46) and HB (PWHB, n: 9) between 2015 and 2019. According to the phenotype, three prophylaxis regimens: 25-50 unit/kg once, twice, or three-times a week for PWHA, and two: 30-50 unit/kg once or twice a week for PWHB were administered. Following the occurrence of > 3 joint bleeding, or > 4 soft tissue bleeding, or one spontaneous major bleeding in the last 3 months, the prophylaxis regimen is changed. Annualized bleeding rate (ABR), annualized joint bleeding rate (AJBR), target joints development, inhibitor development, and hemophilia joint health score (HJHS) also were assessed.

Results: A mean ± SD of 2520 ± 1045 IU/kg/yr coagulation factor (F) VIII was used to reduce ABR and AJBR from 1.02 ± 1.11 and 0.8 ± 1.3 (in the first year of the study) to 0.27 ± 0.44 (P < 0.001) and 0.19 ± 0.38 (P = 0.004) (at the end of the study) in PWHA, respectively. Furthermore, in PWHB, in the first year of the study, with using 2168 ± 1216 IU/kg coagulation FIX, ABR and AJBR were 0.19 ± 0.39 and 0.06 ± 0.1. At the end of the study, ABR and AJBR were 0.02 ± 0.05 (p = 0.156) and 0.01 ± 0.03 (p = 0.361), respectively. During the study period, the mean number of the target joints and mean HJHS were 0.25 ± 0.57 and 7.6 ± 2.1 for PWHA and 0 and 6.3 ± 1.8 for PWHB, respectively. Finally, 5 PWHA (11 %) did not need dose-escalation in their prophylaxis regimen, whereas 31 (67 %) and 10 (21 %) PWHA needed two and three infusions a week, respectively. In PWHB, 7 (78 %) and 2 (22 %) were adjusted to receive a once and twice weekly regimen, respectively.

Conclusion: Our results suggest that tailored prophylaxis is an effective strategy to reduce the rate of bleeding and optimize the replacement therapy in children with hemophilia.