Abstract

An open-label, crossover randomized study was performed to compare the pharmacokinetics (PK) of damoctocog alfa pegol and rurioctocog alfa pegol, two recombinant factor VIII (FVIII) products indicated in patients with hemophilia A, both conjugated to polyethylene glycol to reduce clearance and extend time in circulation. Adult patients (N = 18) with severe hemophilia A (FVIII < 1 IU/dL), previously treated with any FVIII product for ≥ 150 exposure days, were randomized to receive a single 50 IU/kg infusion of damoctocog alfa pegol followed by rurioctocog alfa pegol, or vice versa, with ≥ 7-day washout between doses. FVIII activity was measured using the one-stage clotting assay. PK parameters, including area under the curve from time 0 to the last data point (AUC(0-tlast), primary parameter), dose-normalized AUC (AUC(norm)), and time to threshold, were calculated based on 11 time points between 0.25 and 120 h post-dose and evaluated using a noncompartmental model. Due to differences in batch-specific vial content used for the study, actual administered median doses were 54.3 IU/kg for damoctocog alfa pegol and 61.4 IU/kg for rurioctocog alfa pegol. Based on actual dosing, a significantly higher geometric mean (coefficient of variation [%CV]) AUC(norm) was observed for damoctocog alfa pegol (43.8 h kg/dL [44.0]) versus rurioctocog alfa pegol (36.0 h kg/dL [40.1, P < 0.001]). Based on population PK modeling, median time to reach 1 IU/dL was 16 h longer for damoctocog alfa pegol compared with rurioctocog alfa pegol. No adverse events or any immunogenicity signals were observed. Overall, damoctocog alfa pegol had a superior PK profile versus rurioctocog alfa pegol. Trial registration number: NCT04015492 ( ClinicalTrials.gov identifier). Date of registration: July 9, 2019.

Abstract

BAY 94-9027 is an extended-half-life, recombinant factor VIII (rFVIII) product conjugated with a 60-kDa branched polyethylene glycol (PEG) molecule indicated for use in previously treated patients (aged ≥ 12 years) with hemophilia A. This randomized, open-label, two-way crossover study compared the pharmacokinetics (PK) of BAY 94-9027 and rFVIII Fc fusion protein (rFVIIIFc) in patients with hemophilia A. Patients aged 18-65 years with FVIII < 1% and ≥ 150 exposure days to FVIII were randomized to receive intravenous single-dose BAY 94-9027 60 IU/kg followed by rFVIIIFc 60 IU/kg or vice versa, with ≥ 7-day wash-out between doses. FVIII activity was measured by one-stage assay. PK parameters, including area under the curve from time 0 to the last data point (AUClast, primary parameter), half-life, and clearance were calculated. Eighteen patients were randomized and treated. No adverse events were observed. In the analysis set excluding one outlier, geometric mean (coefficient of variation [%CV, 95% confidence interval {CI}]) AUClast was significantly higher for BAY 94-9027 versus rFVIIIFc (2940 [37.8, 2440-3550] IU h/dL versus 2360 [31.8, 2010-2770] IU h/dL, p = 0.0001). A population PK model was developed to simulate time to reach FVIII threshold levels; median time to 1 IU/dL was approximately 13 h longer for BAY 94-9027 versus rFVIIIFc after a single infusion of 60 IU/kg. In conclusion, BAY 94-9027 had a superior PK profile versus rFVIIIFc. ClinicalTrials.gov : NCT03364998.

Abstract

Regular replacement therapy (prophylaxis) for haemophilia has been shown to prevent development of disabling arthropathy and to provide a better quality of life compared to treatment on demand; however, at a substantially higher cost. Calculations based on pharmacokinetic principles have shown that shortening dose intervals may reduce cost. The aim of this prospective, randomized, crossover pilot study was to address whether daily dosing is feasible, if it reduces concentrate consumption and is as effective in preventing bleeding as the standard prophylactic dosing regimen. In a 12 + 12 month crossover study, 13 patients were randomized to start either their own previously prescribed standard dose, or daily dosing adjusted to maintain at least the same trough levels as obtained with the standard dose. Ten patients completed the study. A 30% reduction in cost of factor concentrates was achieved with daily prophylaxis. However, the number of bleeding events increased in some patients in the daily dosing arm and patients reported decreased quality of life during daily prophylaxis. Daily treatment had a greater impact on daily life, and the patients found it more stressful. Prophylaxis with daily dosing may be feasible and efficacious in some patients. A substantial reduction of factor consumption and costs can be realized, but larger studies are needed before the introduction of daily prophylaxis into clinical routine can be recommended. 2012 Blackwell Publishing Ltd.

Abstract

In an ongoing health-technology assessment of haemophilia treatment in Sweden, performed by the governmental agency Dental and Pharmaceutical Benefits Agency (TLV; tandvards-och lakemedelsformansverket), the Swedish Council on Health Technology Assessment (SBU; statens beredning for medicinsk utvardering) was called upon to evaluate treatment of haemophilia A and B and von Willebrand's disease (VWD) with clotting factor concentrates. To evaluate the following questions: What are the short-term and long-term effects of different treatment strategies? What methods are available to treat haemophilia patients that have developed inhibitors against factor concentrates? Based on the questions addressed by the project, a systematic database search was conducted in PubMed, NHSEED, Cochrane Library, EMBASE and other relevant databases. The literature search covered all studies in the field published from 1985 up to the spring of 2010. In most instances, the scientific evidence is insufficient for the questions raised in the review. Concentrates of coagulation factors have good haemostatic effects on acute bleeding and surgical intervention in haemophilia A and B and VWD, but conclusions cannot be drawn about possible differences in the effects of different dosing strategies for acute bleeding and surgery. Prophylaxis initiated at a young age can prevent future joint damage in persons with haemophilia. The available treatment options for inhibitors have been insufficiently assessed. The economic consequences of various treatment regimens have been insufficiently analysed. Introduction of national and international registries is important. Copyright 2011 Blackwell Publishing Ltd. DO http://dx.doi.org/10.1111/j.1365-2516.2011.02723.x

Abstract

The development of inhibitory antibodies to factor VIII is a serious complication of hemophilia. FEIBA (factor VIII inhibitor-bypassing activity), an activated prothrombin complex concentrate (aPCC), and NovoSeven, recombinant factor VIIa (rFVIIa), are used as hemostatic bypassing agents in treating patients with inhibitors. The FENOC study was designed to test equivalence of the products in the treatment of ankle, knee, and elbow joint bleeding. A prospective, open-label, randomized, crossover, equivalency design was used. The parameters of interest were the percentage of patients who reported efficacy in response to FEIBA and the percentage that reported efficacy in response to NovoSeven. A difference in these percentages of no more than 15% was determined to be a clinically acceptable magnitude for equivalence of the 2 products. The primary outcome was evaluation 6 hours after treatment. Data for 96 bleeding episodes contributed by 48 participants were analyzed. The criterion for declaring the 2 products equivalent at 6 hours was not met; however, the confidence interval of the difference in percentages of efficacy reported for each product only slightly exceeded the 15% boundary (-11. 4%-15. 7%), P=. 059. FEIBA and NovoSeven appear to exhibit a similar effect on joint bleeds, although the efficacy between products is rated differently by a substantial proportion of patients. This trial was registered at www. clinicaltrials. gov as #NCT00166309.

Abstract

OBJECTIVE In order to correct the primary von Willebrand factor (VWF) defect and avoid supra-physiologic plasma levels of factor VIII, a pure VWF concentrate almost devoid of FVIII was developed and used in France since 1989. METHODS The pharmacokinetic (PK) profile of the most recent version of this concentrate (Wilfactin; LFB, Les Ulis, France), treated with three virus-inactivation/removal methods (solvent/detergent, 35 nm filtration, dry heat treatment), was investigated in 25 patients. Seventeen patients with various types of clinically severe von Willebrand disease (VWD) were included in a crossover, randomized trial carried out in five European centers and comparing Wilfactin with concentrates containing both FVIII and VWF (FVIII/VWF). Eight type 3 VWD patients were included in another trial carried out in six French centers comparing Wilfactin with its previous version (Facteur Willebrand-LFB; LFB) that adopted one virus-inactivation method only. RESULTS For both the measurements evaluated in this study (VWF antigen, VWF:Ag; and VWF ristocetin co-factor activity, VWF:RCo), Wilfactin had a PK profile similar to that of the FVIII/VWF concentrates and of Facteur Willebrand-LFB. VWF:RCo and VWF:Ag recoveries were 2. 1 +/- 0. 3 and 1. 8 +/- 0. 3 per IU kg(-1), respectively, and the half-lives were 12. 4 +/- 1. 8 and 15. 9 +/- 1. 5 h. The FVIII synthesis rate was 5. 8 +/- 1. 0 IU dL(-1) h(-1), with a half-life of 15. 8 +/- 2. 4 h. CONCLUSION The PK of VWF and FVIII have not been altered by the three virus-inactivation/removal steps during the manufacturing of Wilfactin.