The Efficacy of Recombinant FVIII Low-Dose Prophylaxis in Chinese Pediatric Patients With Severe Hemophilia A: A Retrospective Analysis From the ReCARE Study

Objective: This study explores the efficacy of recombinant factor VIII (rFVIII) low-dose prophylaxis in Chinese pediatric patients with severe hemophilia A from the Retrospective Study in Chinese Pediatric Hemophilia A Patients With rFVIII Contained Regular Prophylaxis (ReCARE) population. Methods: This is additional analysis of the multicenter, retrospective ReCARE study, in which the annual bleeding rate (ABR), annual joint bleeding rate (AJBR), and safety of > 12-week, low dose (10-30 IU/kg/wk) rFVIII prophylaxis divided into primary, secondary, and tertiary groups based on the joint status and joint bleeding history were analyzed. Results: A total of 57 patients (median age: 8.2 [0.4-17.3] years) from the ReCARE study receiving primary (n = 3), secondary (n = 21), and tertiary (n = 33) prophylaxes were included. Low-dose prophylaxis had significant bleeding reduction in all 3 groups compared to the baseline (S = 408.5, P < .001), with median ABR rates of -4.0 (-8.0 to -3.1), -4.0 (-24.0 to 8.0), and -13.9 (-110.6 to 20.6) in the primary, secondary, and tertiary groups, respectively, with a significant difference between the secondary and tertiary groups (P = .008). Median AJBR reduction rates were -2.3 (-6.3 to 8.4) and -14.9 (-61.5 to 19.1) in the secondary and tertiary groups, respectively. But there was no significant difference in AJBRs between the secondary and tertiary groups (P = .061), which was related to damaged joint status. Hence, longer prophylaxis was associated with better prevention of joint bleeding (P = .024). Conclusion: Despite significant ABR/AJBR reduction in all 3 groups, the efficacy of the primary prophylaxis was better than the secondary and tertiary prophylaxes.