Browsing by Author "Tiede, Andreas (14720292000)"

Background Factor VIII (FVIII) products are usually dosed according to body weight (BW). This may lead to under-or over-dosing in underweight or obese patients, respectively. Objective This article evaluates the pharmacokinetics (PK) of recombinant FVIII concentrate, particularly recovery, in relation to body mass index (BMI) and other body composition descriptors. Materials and Methods Thirty-five previously treated adults with severe haemophilia A from five BMI categories (underweight, normal, overweight, obese class I and II/III) were included. PK was evaluated after 50 IU per kilogram of BW single-dose recombinant FVIII (turoctocog alfa). The body composition variable was based on measurements of weight, height, bioimpedance analysis, and dual-energy X-ray absorptiometry. A dosing model was derived to achieve similar peak FVIII activity levels across BMI categories. Results A statistically significant positive association between BMI and C 30min, IR 30min, and AUC 0-inf was observed; CL and V ss showed a significant negative association with BMI; t ½ was independent of BMI and other parameters. The dosing model introduced a correction factor 'M' for each BMI category, based on linear regression analysis of C 30min against BMI, which ranged from 0.55 for underweight to 0.39 for obese class II/III. This model achieved similar peak FVIII activity levels across BMI categories, estimating an average dose adjustment of +243.3 IU (underweight) to-1,489.6 IU (obese class II/III) to achieve similar C 30min. Conclusion BMI appears to be the best predictor of recombinant FVIII recovery; however, PK endpoints were also dependent on other body composition variables. The model demonstrated that dosing can be adjusted for individual BMI to achieve better FVIII predictability across BMI categories. © 2020 Georg Thieme Verlag KG Stuttgart New York.

Introduction: Turoctocog alfa is a recombinant factor VIII (FVIII) molecule, approved for treatment and prophylaxis of bleeding in patients with haemophilia A. In the guardian 1 (adolescents/adults) and guardian 3 (children) phase 3 trials, turoctocog alfa demonstrated a favourable efficacy and safety profile. Guardian 1 or 3 completers could enrol in the guardian 2 extension. Final guardian 2 results are reported here. Aim: Investigate long-term safety and efficacy of turoctocog alfa administered for prophylaxis and treatment of bleeds. Methods: In this phase 3b open-label trial, previously treated males of all ages with severe haemophilia A received prophylaxis regimens of turoctocog alfa or on-demand treatment of bleeds. The primary safety endpoint was frequency of FVIII inhibitor development. Efficacy endpoints included annualized bleeding rate (ABR) during prophylaxis, haemostatic response in treatment of bleeds and number of injections required to treat bleeds. Results: Overall, 213 patients were dosed with turoctocog alfa; 207 patients received prophylaxis; 19 received on-demand treatment. No FVIII inhibitors (≥0.6 BU) were reported. For all patients on prophylaxis, overall median ABR was 1.37 bleeds/y; success rate for treatment of bleeds was 90.2%; and 88.2% of bleeds were controlled with 1-2 injections of turoctocog alfa. For the on-demand regimen, overall median ABR was 30.44 bleeds/y; success rate for treatment of bleeds was 96.7%; and 94.9% of bleeds were controlled with 1-2 injections of turoctocog alfa. Conclusion: Extended use of turoctocog alfa is safe and effective for prevention and treatment of bleeding episodes in previously treated patients with haemophilia A across all ages. © 2018 The Authors. Haemophilia Published by John Wiley & Sons Ltd.