scholarly journals Design of a prospective observational study on the effectiveness and real-world usage of recombinant factor VIII Fc (rFVIIIFc) compared with conventional products in haemophilia A: the A-SURE study

BMJ Open ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. e028012 ◽  
Author(s):  
Johannes Oldenburg ◽  
Charles R M Hay ◽  
Víctor Jiménez-Yuste ◽  
Flora Peyvandi ◽  
Jean-François Schved ◽  
...  
Keyword(s):  
Factor Viii ◽  
Half Life ◽  
Scientific Journal ◽  
Coagulation Factor ◽  
Clinical Effectiveness ◽  
Ethics Committees ◽  
Primary Objective ◽  
Supplementary Information ◽  
Haemophilia A ◽  
Study Results

IntroductionHaemophilia A is a rare bleeding disorder caused by coagulation factor VIII (FVIII) deficiency. This is treated with factor VIII, conventionally using products with a half-life of 8–12 hours typically administered every 2–3 days. Recombinant FVIII Fc (rFVIIIFc) represents a new generation of products with an extended half-life allowing higher FVIII levels and longer dosing interval. The efficacy and safety of rFVIIIFc have been established in clinical studies and several years of postmarketing use. However, there remains a need to compare treatment outcome with conventional products in routine clinical use.Methods and analysisA-SURE is an ongoing, non-interventional European study with the primary objective to compare the clinical effectiveness of rFVIIIFc with conventional factor products used for haemophilia A prophylaxis. Data covering a 24-month prospective period and a 12-month retrospective period will be collected. Three primary endpoints: bleeding rate, injection frequency and factor consumption will be used to evaluate treatment outcomes. Enrolment of 175 patients on rFVIIIFc and 175 on conventional products is planned. All eligible patients from participating centres will be invited to participate. Visits and treatments follow routine clinical practice. Bias will be reduced by patient matching for age at baseline and the last weekly prophylaxis dose of a conventional product prior to baseline. Propensity scores will be calculated based on prognostic factors and potential confounders assessed at baseline and adjusted for in the estimation of the treatment effect.Ethics and disseminationStudy approval was obtained by local independent ethics committees and/or authorities, and informed consent from patients or their legal representative is a requirement for participation. Names of ethical committees and approval numbers are provided as supplementary information. The study results will be submitted for publication in a peer-reviewed scientific journal and presented at scientific conferences.Trial registration numberNCT02976753, Pre-results.

Continuous infusion of extended half-life factor VIII (efmoroctocog alpha) for surgery in severe haemophilia A

Haemophilia ◽  
2018 ◽  
Vol 24 (4) ◽  
pp. e280-e283
Author(s):  
I. C. L. Kremer Hovinga ◽  
R. E. G. Schutgens ◽  
P. R. van der Valk ◽  
L. F. D. van Vulpen ◽  
E. P. Mauser-Bunschoten ◽  
...  
Keyword(s):  
Factor Viii ◽  
Continuous Infusion ◽  
Half Life ◽  
Haemophilia A ◽  
Severe Haemophilia ◽  
Life Factor

scholarly journals Assessing the Performance of Extended Half-Life Coagulation Factor VIII, FC Fusion Protein by Using Chromogenic and One-Stage Assays in Saudi Hemophilia A Patients

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Tarek M. Owaidah ◽  
Hazzaa A. Alzahrani ◽  
Nouf S. Al-Numair ◽  
Abdulmjeed O. Alnosair ◽  
Amelita M. Aguilos ◽  
...  
Keyword(s):  
Factor Viii ◽  
Half Life ◽  
Hemophilia A ◽  
Coagulation Factor ◽  
Time Interval ◽  
One Stage ◽  
Chromogenic Assay ◽  
Significant Difference ◽  
Mean Differences ◽  
The One

Background. The one-stage assay is the most common method to measure factor VIII activity (FVIII : C) in hemophilia A patients. The chromogenic assay is another two-stage test involving purified coagulation factors followed by factor Xa-specific chromogenic substrate. Aim. This study aimed to assess the discrepancy and correlation between the chromogenic and one-stage assays in measuring FVIII : C levels in hemophilia patients receiving Extended Half-Life Elocta® as a recombinant extended half-life coagulation factor. Methods. We performed a study comparing the measurements of FVIII : C levels by the chromogenic versus the one-stage assays at different drug levels. Data of FVIII : C levels, dosage, and the time interval from administration to measurement were retrieved from the hospital records. The correlation, mean differences, and discrepancy between the two assays were calculated. The linear regression analysis was used to predict the time interval till reaching 1% FVIII : C. Results. Fourteen patients with 56 samples were included in the study. Of them, 13 patients were receiving Elocta® as a prophylactic, while one was receiving Elocta® on demand. One-third of these samples showed a discrepancy between the chromogenic and one-stage assays. The two assays were well correlated. Mean differences were significant at the individual and the time interval level. The time since the last Elocta® injection could significantly predict FVIII : C levels (β = 0.366, P<0.001). Conclusion. Our findings suggested a significant difference between both methods; the FVIII : C levels measured by the one-stage assay were less than those estimated by the chromogenic assay. However, the measurements of FVIII levels by the two assays were well correlated but discrepant in one-third of the samples. The levels of FVIII : C reach 1% after 5.4 days since the last Elocta® administration.

Pharmacokinetics, Coagulation Factor Consumption, and Product Efficacy in Patients Crossing Over from Full-Length FVIII to B-Domain Deleted R-FVIII and Back to Full-Length FVIII.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2269-2269
Author(s):  
Catherine J Rea ◽  
Alex Dunkerley ◽  
Benny Sorensen ◽  
Savita Rangarajan
Keyword(s):  
Clinical Efficacy ◽  
Half Life ◽  
Coagulation Factor ◽  
Outcome Data ◽  
Full Length ◽  
Haemophilia A ◽  
Severe Haemophilia ◽  
Efficacy And Safety ◽  
Significant Difference ◽  
Recovery Times

Abstract Introduction: Treatment with B-domain deleted recombinant factor VIII (BDD-rFVIII) has proven to be effective and safe both in clinical trials and post marketing surveillance studies. However, intermittent concerns have been raised regarding the pharmacokinetic performance, efficacy and incidence of inhibitor formation with the BDD-rFVIII product. Aims: The objective of the present study was to perform a retrospective survey of half-life measurements, clinical efficacy and safety in patients with severe Haemophilia A, when switching treatment from full-length FVIII (FL-FVIII) to BDD- rFVIII and then back to full-length FVIII. We hypothesized that the biological half-life of FVIII would be equal regardless of the product used. Furthermore, we hypothesized that the total factor consumption and bleeding frequency would be indistinguishable irrespective of product used. Finally, we report on safety as evaluated by development of inhibitors and clinical outcome following surgery. Methods: Patients treated with BDD-rFVIII (between 1998 and 2008) were identified from an in-house database. Data collected included annual half-life (T/2) and recovery times (K values), total coagulation factor consumption, and number of bleeds per year as measures of clinical efficacy. Safety data consisted of surgical outcome data and incidence of inhibitor formation. The information was extracted from electronic databases and verified by a review of patients’ clinical notes. The outcome data was non-parametric, hence, paired analysis was performed using Wilcoxon signed rank test and Friedman ANOVA. Data is given as a median value and range. P-value &lt; 0.05 was set as level of statistical significance. Results: In total, 70 patients received BDD-rFVIII on at least one occasion. Following a specified list of criteria, evaluable data was obtainable for 15 males, all with verified severe Haemophilia A (FVIII:C &lt;1%). The average age was 10.2 years (median 10, range 4–17). The median duration on BDD-rFVIII was 30 months (range 20–54). Using the one-way non-parametric ANOVA, no statistically significant difference was detected between the half-life and recovery times recorded during the switch from FL-FVIII (T/2 median 9.15 hours, range 6.4–22; K median 2.7, range 2.0–3.4) to BDD-rFVIII (T/2 median 9.7, range 4.7–16.8; K median 1.8, range 1.0–3.5) and back to FL-FVIII (T/2 median 9.0, range 5.0–19.5; K median 2.0, range 1.6–2.8). Furthermore, there was no significant difference in coagulation factor usage (BDD-rFVIII median 4803 iu/kg/year, range 659–11304; FL-FVIII median 5349, range 1691–10146), nor number of reported bleeds (BDDrFVIII median 6, range 0–24; FL-FVIII median 5.0, range 0–17). None of the 15 patients developed an inhibitor on BDD-rFVIII. Of the total 70 patients, 11 received BDD-rFVIII to cover surgical procedures (8 minor, 3 major interventions). There were no reports of excess bleeding. Conclusions: In this retrospective survey, BDD-rFVIII was found to be equivalent to other FVIII products in terms of half-life measurements, clinical efficacy and safety.

Neutralisation of factor VIII inhibitors by anti-idiotypes isolated from phage-displayed libraries

2016 ◽  
Vol 116 (07) ◽  
pp. 32-41 ◽  
Author(s):  
Anja Schmidt ◽  
Kerstin Brettschneider ◽  
Jörg Kahle ◽  
Aleksander Orlowski ◽  
Karin Becker-Peters ◽  
...  
Keyword(s):  
Factor Viii ◽  
Tolerance Induction ◽  
Coagulation Factor ◽  
Cross Reactivity ◽  
Hybridoma Cells ◽  
Haemophilia A ◽  
Immune Tolerance Induction ◽  
Fviii Inhibitor ◽  
Antiidiotypic Antibody

SummaryFollowing replacement therapy with coagulation factor VIII (FVIII), up to 30 % of haemophilia A patients develop FVIII-specific inhibitory antibodies (FVIII inhibitors). Immune tolerance induction (ITI) is not always successful, resulting in a need for alternative treatments for FVIII inhibitor-positive patients. As tolerance induction in the course of ITI appears to involve the formation of anti-idiotypes specific for anti-FVIII antibodies, such anti-idiotypes might be used to restore haemostasis in haemophilia A patients with FVIII inhibitors. We isolated antiidiotypic antibody fragments (scFvs) binding to murine FVIII inhibitors 2-76 and 2-77 from phage-displayed libraries. FVIII inhibitor/anti-idiotype interactions were very specific as no cross-reactivity with other FVIII inhibitors or isotype controls was observed. ScFvs blocked binding of FVIII inhibitors to FVIII and neutralised their cognate inhibitors in vitro and a monoclonal mouse model. In addition, scFv JkH5 specific for FVIII inhibitor 2-76 stained 2-76-producing hybridoma cells. JkH5 residues R52 and Y226, located in complementary determining regions, were identified as crucial for the JkH5/2-76 interaction using JkH5 alanine mutants. SPR spectroscopy revealed that JkH5 interacts with FVIII inhibitor 2-76 with nanomolar affinity. Thus, FVIII inhibitorspecific, high-affinity anti-idiotypes can be isolated from phagedisplayed libraries and neutralise their respective inhibitors. Furthermore, we show that anti-idiotypic scFvs might be utilised to specifically target inhibitor-specific B cells. Hence, a pool of anti-idiotypes could enable the reestablishment of haemostasis in the presence of FVIII inhibitors in patients or even allow the depletion of inhibitors by targeting inhibitor-specific B cell populations.

F VIII Inhibitors in Haemophilia A Patients after Continuous Infusion of Factor VIII Concentrates.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3100-3100
Author(s):  
Ch. von Auer ◽  
J. Oldenburg ◽  
M. von Depka ◽  
C. Escuriola-Ettinghausen ◽  
W. Kreuz ◽  
...  
Keyword(s):  
Factor Viii ◽  
Continuous Infusion ◽  
Orthopaedic Surgery ◽  
Coagulation Factor ◽  
Haemophilia A ◽  
Missense Mutations ◽  
Factor Viii Concentrates ◽  
Coagulation Factor Concentrates ◽  
Major Orthopaedic Surgery ◽  
Mild Haemophilia

Abstract Continuous infusion (CI) of coagulation factor concentrates has been used since the early 1990s. Recent reports of the occurrence of an inhibitor (inh) after CI have raised concerns about this method of treatment. We conduct a retrospective study to investigate the development of inh after CI of FVIII concentrates in Germany. 99 haemophilia treating physicians in Germany were contacted and asked to answer a questionnaire. So far data of 13 departments have been reported and analyzed. Three of these 13 centers never conducted a CI, in 5 no inh were detected and in 5 haemophilia centers 10 patients with inh development after CI were registered. 5 of these patients were suffering from severe, 1 from moderate and 4 from mild haemophilia (age between 7 months and 57 years). Indications for treatment were major bleeds and surgical procedures. Plasma derived (6) and recombinant (4) factor concentrates were given in various infusion sets. Data concerning infused amount (4300 to >100000 IE), exposure days (1 to >100) and inh characteristic (alloantibodies, 3 LR, 7 HR) were collected. Regarding the genotype, we found 4 missense-mutations, 2 intron-22-inversions, 1 small deletion, 3 were unknown. In our own center we found no inh in 81 patients with major orthopaedic surgery and bolus infusion of factor VIII concentrate compared to 2 inh in 8 patients with major orthopaedic surgery and CI of FVIII. In conclusion we found only in 2 patients the typical gene mutation for inh development. Strikingly the inh developed very often in patients with mild haemophilia. These findings agree with published results. There might be an uncommon inh-pathomechanism due to CI or patients with mild haemophilia might exhibit a much higher prevalence of inhibitor development when treated with an “intensive FVIII-treatment” such as CI.

Investigation of Underlying Reasons of Factor VIII Deficiency in Haemophilia A Patients with Undetectable Mutations in the Factor VIII Gene.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1042-1042
Author(s):  
Osman El-Maarri ◽  
Jörg Schröder ◽  
Claudia Klein ◽  
Rainer Schwaab ◽  
Anne Goodeve ◽  
...  
Keyword(s):  
Factor Viii ◽  
Coagulation Factor ◽  
Causative Mutation ◽  
Haemophilia A ◽  
Rt Pcr ◽  
Factor Viii Gene ◽  
Total Blood ◽  
Reverse Transcription Pcr ◽  
Multi Center Study ◽  
Center Study

Abstract Haemophilia A (HA) is an X-linked bleeding disorder caused by heterogeneous mutations in the coagulation factor VIII (F8) gene. Despite applying sensitive methods for mutation detection, and after excluding the inversions mutations a causative mutation is not identified in F8 gene in about 2,5% of severe HA patients (53 patients out of 2350 German patients). Analysis of mRNA from a small group of such (German) patients has excluded mutations deep in the introns that may affect normal splicing or mechanisms causing some unknown rearrangements of the F8 gene as the cause of HA. Among this group, in one patient no F8 mRNA was detected. Using two common polymorphisms in F8 exon 14, we were able to show that the same allele shared by the patient, his mother and his sister was not detected by reverse transcription PCR (RT-PCR) from total blood mRNA. These findings strongly suggest that the cause of HA in this patient is either absence or rapid degradation of the F8 mRNA which points to a novel mechanism leading to HA. To further investigate the cause of Hemophilia A in these patients an international multi-center study was established. The aim of this study to assemble a large collection of such families that could provide clues for novel factors/mechanisims that are important for the F8 molecule biogenesis and protein regulation as well as F8 expression. This multi-center study is therefore suposed to identify novel mechanisms causing HA.

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