Clinical experience with moroctocog alfa (AF-CC) in younger paediatric patients with severe haemophilia A: Two open-label studies

Abstract

Introduction: The pharmacokinetics (PK), efficacy and safety of moroctocog alfa (AF-CC) have been demonstrated in haemophilia A patients aged ≥6 years.

Aim: These studies aimed to further describe moroctocog alfa (AF-CC) experience in paediatric patients (<12 years) with severe haemophilia A (FVIII:C < 1%).

Methods: Two prospective, open-label studies enrolled patients aged <12 years: one study with 37 previously treated patients (PTPs) and another with 23 previously untreated patients (PUPs). All patients initially received 50 IU/kg of moroctocog alfa (AF-CC) to evaluate either recovery alone, or with other PK parameters (6 to <12 years) before continuing treatment for 100 exposure days (EDs) or 24 months.

Results: At baseline, mean (±SD) recovery ranged between 1.32 ± 0.65 (PUPs aged <2 years) and 2.13 ± 0.82 (PTPs aged 6 to <12 years). The mean (±SD) half-life was 9.12 ± 1.94 hours in PTPs aged 6 to <12 years. No new safety signals were detected in either study, 2 transient lower titre inhibitors occurred in PTPs while 8 inhibitors (3 low and 5 high titre) were detected in PUPs. Most bleeding episodes resolved with one infusion (94% [893/954]). The annualised bleeding rate (ABR) in the PTP study was 27.5 and 4.2 for patients reporting an on-demand and routine prophylaxis regimen at baseline, respectively. In the PUP study, the overall ABR was 5.9.

Conclusion: Moroctocog alfa (AF-CC) had expected PK findings (lower recovery in young children compared with older children) along with being safe and efficacious in a population of young severe haemophilia A patients.

Keywords: clinical trial; factor replacement; pharmacokinetics; previously treated patients; previously untreated patients; recombinant factor VIII.