Abstract Number: PB0901
Meeting: ISTH 2020 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Hemophilia - Clinical
Background: Hemophilia A (HA) is an inherited bleeding disorder characterized by deficiency of procoagulant factor VIII (FVIII). Prophylaxis with FVIII is the most effective treatment in patients with moderate/severe (ms) HA (FVIII:C< 5%), which can prevent spontaneous bleeding episodes. Although standard prophylaxis based on body weight and at least 1% of plasmatic FVIII trough levels is effective, spontaneous bleeding still occurs. The modern individualized therapy then considers patient behaviour and FVIII pharmacokinetic (PK) parameters.
Aims: The aim of this study is to describe the PK profiles of msHA patients who were submitted to PK-individualized therapy with octocog alfa (rFVIII).
Methods: Patients were invited from two Southern Brazilian hemophilia treatment centers, if they were 1 year or older, they weighed at least 12 kg, their inhibitor status was negative for at least 6 months, they had ≥ 50 exposition days and they were bleeding-free for at least 2 weeks. Data were obtained from medical files. PK profile was calculated according to the myPKFiT protocol.
Results: Thirty-three patients on PK-individualized prophylaxis were included. Median age was 12.0 [IQR,8.0-24.0] years. One patient was excluded from the analyses because his FVIII half-life was below the normal value. Patients were divided in two groups: younger than 15 years (n=21) and 15 years or more (n=12). Median FVIII half-life was statistically lower (p=0.001) and median clearance was statistically higher (p=0.016) in the youngest patient group than in the oldest group, although the estimated doses to keep FVIII trough level of at least 1% with each-other-day infusion were similar between the groups (p=0.065).
Conclusions: Our results confirm previous studies which described a shorter FVIII half-life among children, but surprisingly the estimated doses to keep a trough level above 1% were similar between the age groups. The significance of these findings will be further elucidated after inclusion and follow-up of new patients.
To cite this abstract in AMA style:
Borges A, Giacometto P, Anegawa T, Hirle L, Amarante M, Jardim L, Camelo R. Pharmacokinetic Profile of Southeastern Brazilian Hemophilia A Patients on Prophylaxis with Octocog Alfa [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/pharmacokinetic-profile-of-southeastern-brazilian-hemophilia-a-patients-on-prophylaxis-with-octocog-alfa/. Accessed October 2, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/pharmacokinetic-profile-of-southeastern-brazilian-hemophilia-a-patients-on-prophylaxis-with-octocog-alfa/