Abstract Number: PB0646
Meeting: ISTH 2021 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Hemophilia - Clinical
Background: Hemophilia concentrates’ pharmacokinetics (PKs) have important variability between patients, for this reason standard doses often result far from goal plasmatic concentrations. Prophylactic treatment efficacy, which has become the gold-standard in patients with moderate or severe hemophilia, is based on plasmatic concentrations which depends on several variables: genotype, fenotype, bleeding events (intensity, location, frequency), lifestyle, age, weight and physical activity, among others. PK-guided approach is necessary in these patients to personalize each treatment.
Aims: Clinical and pharmacokinetic assessment of hemophilia B patients with prophylactic treatment, who have been switched from standard recombinant products (SHL) to extend half-life recombinant factors (EHL).
Methods: PKs were assessed in four hemophilia B patients with prophylactic treatment based on SHL who were switched in December 2020 to EHL factors. Data was collected from medical records and PK software, results were compared to prior prophylaxis regimen.
Results:
The patients, all males, three diagnosed with severe and one with moderate hemophilia B had been receiving infusions of SHL productos, mean doses of 40 UI/kg twice a week, and with trough levels from 2 to 5%. After switching to EHL factors through levels achieved were from 5 to 12% with doses of 35-50 UI/kg each week or each two weeks. However, all patients had joint bleeding and ache after switching.
Conclusions: Switch to EHL was associated with an improvement in PK profile and dosification without improving clinical outcome. These results raised questions about the convenience of PK-guided approaches in these treatments.
To cite this abstract in AMA style:
Álvarez Tosco KI, Ocaña Gómez MÁ, Ríos de Paz AM, De Dios García MD, Mesa Lorenzo MC, Merino Alonso J. Clinical and Pharmacokinetic Assessment after Switching to an Extended Half-life Product for Prophylaxis in Haemophilia B [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/clinical-and-pharmacokinetic-assessment-after-switching-to-an-extended-half-life-product-for-prophylaxis-in-haemophilia-b/. Accessed August 15, 2022.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/clinical-and-pharmacokinetic-assessment-after-switching-to-an-extended-half-life-product-for-prophylaxis-in-haemophilia-b/