Individual thrombin generation and spontaneous bleeding rate during personalized prophylaxis with Nuwiq® (human-cl rhFVIII) in previously treated patients with severe haemophilia A.

INTRODUCTION: For individuals with haemophilia A, prophylaxis with factor VIII (FVIII) is typically directed towards trough activity >1 IU/dL; however, some patients still experience spontaneous bleeding events (sBEs). AIM: Aims were to evaluate relationships of endogenous thrombin potential (ETP) and FVIII:C with occurrence of clinical bleeding. METHODS: GENA-21 was a prospective, open-label, phase IIIb study investigating the safety and efficacy of Nuwiq® (human-cl rhFVIII) in previously treated adults with severe haemophilia A. The study included a 72-hour pharmacokinetic (PK) evaluation phase and a 6-month personalized prophylaxis phase in which treatment was guided by PK parameters. This subanalysis assessed FVIII:C by one-stage assay and ETP by thrombin generation assay in blood samples. RESULTS: Baseline mean ETP was lower in the 7 patients who experienced sBEs during personalized prophylaxis versus 25 who did not (n = 32 with data from PK phase and prophylaxis phase; P = .0002). During personalized prophylaxis (n = 49), only patients with lower median trough ETP experienced sBEs (8/49 patients; ROC AUC = 0.9421; P < .0001); there was no significant relationship for FVIII:C in predicting sBEs (ROC AUC = 0.5838; P = .4750). Directly following infusion of human-cl rhFVIII, ETP was lower in patients who experienced sBEs versus those who did not (P = .0002), whereas FVIII:C did not differ significantly between these groups. CONCLUSIONS: In adults with severe haemophilia A and reduced thrombin generation, increased frequency of spontaneous bleeding was observed irrespective of trough FVIII levels. Thus, personalized prophylaxis should take into account variables other than FVIII:C. Large prospective trials are needed to verify ETP as a marker for spontaneous bleeding.

Prospects for research in haemophilia with real-world data-An analysis of German registry and secondary data.

INTRODUCTION AND AIM: Open questions in haemophilia, such as effectiveness of innovative therapies, clinical and patient-reported outcomes (PROs), epidemiology and cost, await answers. The aim was to identify data attributes required and investigate the availability, appropriateness and accessibility of real-world data (RWD) from German registries and secondary databases to answer the aforementioned questions. METHODS: Systematic searches were conducted in BIOSIS, EMBASE and MEDLINE to identify non-commercial secondary healthcare databases and registries of patients with haemophilia (PWH). Inclusion of German patients, type of patients, data elements-stratified by use in epidemiology, safety, outcomes and health economics research-and accessibility were investigated by desk research. RESULTS: Screening of 676 hits, identification of four registries [national PWH (DHR), national/international paediatric (GEPARD, PEDNET), international safety monitoring (EUHASS)] and seven national secondary databases. Access was limited to participants in three registries and to employees in one secondary database. One registry asks for PROs. Limitations of secondary databases originate from the ICD-coding system (missing: severity of haemophilia, presence of inhibitory antibodies), data protection laws and need to monitor reliability. CONCLUSION: Rigorous observational analysis of German haemophilia RWD shows that there is potential to supplement current knowledge and begin to address selected policy goals. To improve the value of existing RWD, the following efforts are proposed: ethical, legal and methodological discussions on data linkage across different sources, formulation of transparent governance rules for data access, redefinition of the ICD-coding, standardized collection of outcome data and implementation of incentives for treatment centres to improve data collection.

Co-morbidities and bleeding in elderly patients with haemophilia-A survey of the German, Austrian and Swiss Society of Thrombosis and Haemostasis Research (GTH).

BACKGROUND: Nowadays patients with haemophilia survive longer due to improvements in haemophilia care. It has been hypothesized that the bleeding type and frequency may vary with age and are influenced by co-morbidities and co-medication in elderly patients. OBJECTIVES: To investigate a large group of patients older than 60 years of age with haemophilia concerning haemophilia treatment, bleeding pattern changes, co-morbidities, co-medication, bleeding sites and patient mortality. METHODS: A retrospective multi-centre data collection study was initiated on behalf of the German, Austrian and Swiss Society of Thrombosis and Haemostasis Research (GTH). Parameters of interest were investigated over the 5 years prior to study entry. RESULTS: A total of 185 haemophilia patients (mean age, 69.0±7.0 years, 29% with severe haemophilia) were included in the study. Regular prophylaxis was performed in 30% of the patients with severe haemophilia. In total, the annual bleeding rate was 2.49 and in patients with severe haemophilia 5.61, mostly caused by joint bleeds. Hypertension was the most common co-morbidity, but it occurred significantly less frequently than in an age-matched general population older than 70 years; 12% of the patients suffered from ischaemic heart disease, and 13% of the patients received anticoagulant or antiplatelet therapy. Within the observation period, 17% of the patients with severe haemophilia developed a higher frequency of bleeding symptoms, which was significantly associated with the use of antiplatelet or anticoagulant drugs. CONCLUSIONS: The most common co-morbidity of the patient population was hypertension, a considerable part had ischemic heart disease and antiplatelet or anticoagulant drugs.

PK-guided personalized prophylaxis with Nuwiq® (human-cl rhFVIII) in adults with severe haemophilia A.

INTRODUCTION: Nuwiq® (human-cl rhFVIII) is a 4th generation recombinant human FVIII, without chemical modification or protein fusion, produced in a human cell-line. AIMS/METHODS: This study (NuPreviq) was a prospective, open-label, multicentre, phase IIIb study of the efficacy and safety of personalized prophylaxis with Nuwiq® in 66 previously treated adults with severe haemophilia A. NuPreviq had three phases: (i) a 72-h pharmacokinetic (PK) phase; (ii) a 1-3 month standard prophylaxis phase; and (iii) a 6-month personalized prophylaxis phase. The personalized prophylaxis regimen was based on individual PK modelling for each patient according to whether their PK profile most closely fitted a two- or one-compartment model (NuPreviq approach). In cases of uncertainty, a noncompartment model was applied. RESULTS: The median dosing interval during personalized prophylaxis was 3.5 days, with 57% of patients on ≤2 weekly dosing. Mean annualized bleeding rates during personalized prophylaxis were 1.45 (median [interquartile range, IQR]: 0 [0, 1.9]) for all bleeds, 0.79 (median [IQR]: 0 [0, 0]) for spontaneous bleeds, and 0.91 (median [IQR]: 0 [0, 0]) for joint bleeds. During personalized prophylaxis, 83.1% of patients were spontaneous bleed-free. Compared with standard prophylaxis, median weekly prophylaxis dose was reduced by 7.2% from 100.0 to 92.8 IU kg-1 during the last 2 months of personalized prophylaxis. There were no FVIII inhibitors or treatment-related serious or severe adverse events. CONCLUSION: PK-guided personalized prophylaxis with Nuwiq® provided bleeding protection and enabled the dosing interval to be extended to twice weekly or less in many patients and an overall dose reduction.

Outcome measures in European patients with haemophilia: Survey of implementation in routine clinical practice, perception of relevance and recommendations by European treaters in the EHTSB.

INTRODUCTION: This study was conducted to evaluate the current implementation of outcome measures in routine clinical haemophilia practice and to explore and appreciate the perception of the relevance of such measures by treaters. METHODS: A survey was completed by 19 of the 26 physicians involved in the European Haemophilia Therapy Strategy Board (EHTSB). Employing an extensive inventory of outcome measures used in patients with haemophilia, information was collected about the frequency of data collection and the subjective appreciation of their importance during clinic review. RESULTS: The survey revealed that most treaters currently collect data that are mainly related to the haemostatic treatment (consumption of concentrates) and the bleeding symptoms (number and location of bleeds) in a non-uniform and non-standardized way. By contrast, functional, physical and quality of life scorings are rarely used and show considerable heterogeneity between treaters. Also, many disparities emerged between practice and perception, in particular quality of life data that are perceived as being important but for most of the time are not collected. CONCLUSIONS: This survey represents, in our view, the first attempt to evaluate the actual utilization of outcome measures in haemophilia care. While the value of outcome measures is appreciated, they are not assessed regularly. Therefore, there is a need to include appropriate performance indicators (outcome measures) of haemophilia care in routine clinical practice. Consensus recommendations to provide a framework for achieving this aim are provided.

How to compare cardiovascular disease and risk factors in elderly patients with haemophilia with the general population.

INTRODUCTION: Studies on the prevalence of cardiovascular disease (CVD) and risk factors in patients with haemophilia (PWH) in comparison to the general population have generated inconsistent results. The ADVANCE Working Group collected data on CV comorbidities in PWH aged ≥40 years (H(3) Study). AIM: Identification of German epidemiological data on CVD for the general population, evaluation for appropriateness, and execution of comparisons with PWH. METHODS: Identification of data sources by structured literature (EMBASE, MEDLINE) searches. INCLUSION CRITERIA: German general population, CVD and risk factors, gender/age stratification, sample size >500 male persons, age groups ≥40 years, current data collection, language English/German. Comparison of data on CVD and risk factors in PWH (H(3)  Study) with published German general population data. RESULTS: Criteria for data source appropriateness were defined. Of five national and three international epidemiological studies, the DEGS1 Study (German Health Interview and Examination Survey for Adults) was identified as the most suitable comparator. Compared with men from DEGS1, hypertension was significantly more prevalent in PWH aged 50-59 years (41.7% [95% CI: 37.3-46.2] vs. 52.0% [95% CI: 43.7-60.1], P = 0.03). Coronary artery/heart disease (CHD) was significantly less prevalent in PWH aged ≥60 years (60-69 years: 19.5% [95% CI: 15.9-23.7] vs. 8.1% [95% CI: 3.3-16.1], P = 0.02; 70-79 years: 30.5% [95% CI: 25.9-35.5] vs. 11.8% [95% CI: 5.2-21.9], P = 0.002). No statistically significant difference for ischaemic cerebrovascular disease/stroke was detected. CONCLUSION: Increased prevalence of hypertension in PWH should trigger regular screening. CHD does occur in PWH aged ≥60 years though apparently with lower prevalence. Given the growing population of elderly PWH, guidelines for prevention and treatment of CVD should be developed.

Comparative pharmacokinetics of rVIII-SingleChain and octocog alfa (Advate(®) ) in patients with severe haemophilia A.

BACKGROUND: rVIII-SingleChain, a novel recombinant factor VIII (rFVIII), has been designed as a B-domain truncated construct with covalently bonded heavy and light chains, aiming to increase binding affinity to von Willebrand factor (VWF). Preclinical studies confirmed greater affinity for VWF, giving improved pharmacokinetic and pharmacodynamic properties compared with full-length rFVIII. AIM: To investigate the pharmacokinetics of rVIII-SingleChain and compare them against those of full-length rFVIII. METHODS: This study enrolled 27 patients with severe haemophilia A in the AFFINITY clinical trial programme. After a 4-day washout period, all patients received a single infusion of 50 IU kg(-1) octocog alfa (Advate(®) ); after a ≥4-day postinfusion washout period, they received a single infusion of 50 IU kg(-1) rVIII-SingleChain. Blood samples for pharmacokinetic assessments of each product were collected before infusion (predose) and at 0.5, 1, 4, 8, 10, 24, 32, 48 and 72 h postinfusion for both products. RESULTS: rVIII-SingleChain had a longer mean half-life (t1/2 ) (14.5 vs. 13.3 h), lower mean clearance (CL) (2.64 vs. 3.68 mL h(-1) kg(-1) ), higher mean residence time (20.4 vs. 17.1 h) and larger mean AUCinf (2090 vs. 1550 IU?h dL(-1) ) than octocog alfa, respectively. The mean AUCinf after rVIII-SingleChain infusion was ~35% larger than after octocog alfa. A similar pattern was observed for AUC0-last . No serious adverse events or inhibitors were reported. CONCLUSIONS: rVIII-SingleChain has a favourable pharmacokinetic profile compared with octocog alfa and was well tolerated. The prolonged t1/2 , larger AUC and reduced CL of rVIII-SingleChain may permit longer dosing intervals, thereby improving patient adherence to prophylactic treatment.

Prospective evaluation of treatment regimens, efficacy and safety of a recombinant factor VIII concentrate in haemophilia A: the German EffeKt study.

INTRODUCTION: Collecting clinical data under routine conditions remains important to monitor continuously efficacy and tolerability of an established product. AIM: This prospective observational study aimed at evaluating efficacy and tolerability of full-length sucrose-formulated recombinant FVIII (rFVIII-FS; KOGENATE(®) Bayer/KOGENATE(®) FS) in routine use and analysing concomitant diseases and medication. METHODS: Haemophilia A patients treated with rFVIII-FS were followed up for 24 or 36 months. Efficacy, tolerability, concomitant medication and diseases were assessed at yearly intervals. RESULTS: Two hundred and twenty-one documented patients were mainly pretreated, predominantly with prophylaxis (74%). On study, 54 (31%) patients in the efficacy set (n = 174) documented regular prophylaxis, 91 patients (52.3%) failed to document their prescribed prophylactic infusions, 25 (14.4%) received on-demand treatment and four patients (2%) inhibitor adapted therapy. Patients on regular prophylaxis reported 8.4% of infusions for bleeding treatment and on-demand patients reported 55.3%. Young patients experienced mainly trauma-related bleedings and older patients reported spontaneous bleedings. Joint status was good overall. Median annual spontaneous joint bleeding rate in all groups was zero. A total of 79.0% of all bleedings were successfully treated with one or two infusions. Degenerative arthropathy and arterial hypertension were the most prominent concomitant diseases. Eighty-seven patients (40.5%) took at least one concomitant drug on study, mostly drugs for pain treatment related to haemophilic arthropathy. Two patients presented with positive inhibitor titres on study, one of them was a previously untreated patient and the other had a positive inhibitor history. CONCLUSION: This study corroborates the tolerability and efficacy profile of rFVIII-FS.

Diagnostic and prognostic value of factor VIII binding antibodies in acquired hemophilia A: data from the GTH-AH 01/2010 study.

UNLABELLED: Essentials Factor VIII (FVIII) binding IgG detected by ELISA could be an alternative to the Bethesda assay. We studied the performance of anti-FVIII IgG ELISA in patients with acquired hemophilia and controls. Anti-FVIII IgG > 99th percentile of controls was highly sensitive and specific. Patients with high anti-FVIII IgG have a lower chance of achieving remission. SUMMARY: Background Acquired hemophilia A is a severe bleeding disorder that requires fast and accurate diagnosis as it occurs often unexpectedly in previously healthy men and women of every age. The Nijmegen-modified Bethesda assay is the diagnostic reference standard for detecting neutralizing autoantibodies against factor VIII (FVIII), but is not widely available, not ideal for quantifying the complex type 2 inhibitors seen in acquired hemophilia, and suffers from high inter-laboratory variability. Objectives To assess the diagnostic and prognostic value of FVIII-binding antibodies as detected by ELISA compared with the Nijmegen Bethesda assay. Methods Samples from the time of first diagnosis and clinical data were available from 102 patients with acquired hemophilia enrolled in the prospective GTH-AH 01/2010 study. Controls (n = 102) were matched for gender and age. Diagnostic cut-offs were determined by receiver-operator curve analysis. The prognostic value was assessed in 92 of the 102 patients by Cox regression analysis of time to partial remission. Results Anti-FVIII IgG above the 99th percentile (> 15 arbitrary units per mL) revealed high sensitivity and specificity (both 0.99; 95% confidence interval, 0.95-1.0) for diagnosing acquired hemophilia. The likelihood of achieving partial remission was related to anti-FVIII IgG concentration (< 300 arbitrary units, 1.0; 300-1050, 0.65; > 1050, 0.39). The Bethesda titer was only associated with the likelihood of partial remission when analyzed in the central laboratory, but not when data from local GTH study sites were used. Conclusion Although the Nijmegen-modified Bethesda assay is the reference standard for demonstrating neutralizing antibodies, the detection of FVIII-binding antibodies by ELISA is similarly sensitive and specific for diagnosing acquired hemophilia. In addition, anti-FVIII IgG may provide prognostic information.

Turoctocog alfa (recombinant factor VIII). Manufacturing, characteristics and clinical trial results.

Turoctocog alfa (NovoEight®) is a new recombinant factor VIII (rFVIII) with a truncated B domain and a high degree of tyrosine sulphation, similar to plasma-derived FVIII products. The manufacturing process includes double nanofiltration with a 20-nm pore size and immunoaffinity chromatography with monoclonal F25 anti-FVIII antibodies. Treatment with turoctocog alfa can be monitored with both one-stage and chromogenic substrate assays without a product-specific laboratory standard. In total, 213 previously-treated patients with severe haemophilia A participated in the pivotal part of the clinical trial programme guardianTM. The median annualised bleeding rate during turoctocog alfa prophylaxis was 3.7 and 3.0 in adolescents/adults and children, respectively, with marked differences between participating countries. The success rate for the treatment of breakthrough bleeds was 85% (adults/adolescents) and 94% (children). A total of 41 surgical procedures (15 major, 26 minor) were performed in 33 patients, with a successful haemostatic response reported in all cases. No patient developed confirmed inhibitors in any of the trials.

How fit are children and adolescents with haemophilia in Germany? Results of a prospective study assessing the sport-specific motor performance by means of modern test procedures of sports science.

There are a lot of publications on the physical fitness of patients with haemophilia (PWH), however, most studies only reflect individual sport-specific motor capacities or focus on a single fitness ability. They involve small patient populations. In this respect principal objective of this study was to compare the physical fitness in all respects and the body composition of young PWH to healthy peers based on the most valid data we could get. Twenty-one German haemophilia treatment centres were visited from 2002 to 2009. PWH between 8 and 25 years were included. They performed a five-stage fitness test covering the sport-specific motor capacities for coordination, measured by one leg stand, strength, aerobic fitness and mobility as well as body composition. The patients' results were compared with age- and gender-specific reference values of healthy subjects. Two hundred and eighty-five PWH (mean age 13.2 ± 4.5 years, 164 PWH with severe disease) were included prospectively in the study. PWH are significantly below the reference values of healthy subjects in the one-leg stand test, the mobility of the lower extremity, the strength ratio of chest and back muscles and the endurance test. In body composition, the back strength and the mobility of the upper extremity PWH are significantly above the reference values. There are no significant differences in abdominal strength. In conclusion we found specific differences in different fitness abilities between PWH and healthy subjects. Knowing this, we are able to work out exercise programmes to compensate the diminished fitness abilities for our PWH.

Safety and pharmacokinetics of anti-TFPI antibody (concizumab) in healthy volunteers and patients with hemophilia: a randomized first human dose trial.

BACKGROUND: Prophylaxis with either intravenous (i.v.) factor VIII (FVIII) or FIX is the gold standard of care for patients with severe hemophilia. A monoclonal antibody (concizumab) targeting tissue factor pathway inhibitor (TFPI) that can be administered subcutaneously (s.c.) has the potential to alter current concepts of prophylaxis in hemophilia. OBJECTIVES: To evaluate the safety and describe the pharmacokinetics and pharmacodynamics of single-dose concizumab in healthy volunteers and patients with hemophilia A or B. METHODS: In this first human dose, phase 1, multicenter, randomized, double-blind, placebo-controlled trial escalating single i.v. (0.5-9000 µg kg(-1) ) or s.c. (50-3000 µg kg(-1) ) doses of concizumab were administered to healthy volunteers (n = 28) and hemophilia patients (n = 24). RESULTS: Concizumab had a favorable safety profile after single i.v. or s.c. administration. There were no serious adverse events and no anti-concizumab antibodies. No clinically relevant changes in platelets, prothrombin time, activated partial thromboplastin time, fibrinogen, or antithrombin were found. A dose-dependent procoagulant effect of concizumab was seen as increased levels of D-dimers and prothrombin fragment 1 + 2. Nonlinear pharmacokinetics of concizumab was observed due to target-mediated clearance. A maximum mean AUC0-∞ of 33 960 h µg mL(-1) and a maximum mean concentration of 247 µg mL(-1) was measured at the highest dose. CONCLUSIONS: Concizumab showed a favorable safety profile after i.v. or s.c. administration and nonlinear pharmacokinetics was observed due to target-mediated clearance. A concentration-dependent procoagulant effect of concizumab was observed, supporting further study into the potential use of s.c. concizumab for hemophilia treatment.

The pharmacokinetics of a B-domain truncated recombinant factor VIII, turoctocog alfa (NovoEight®), in patients with hemophilia A.

BACKGROUND: Turoctocog alfa (NovoEight(®)) is a human recombinant coagulation factor VIII (rFVIII) for the treatment of patients with hemophilia A. OBJECTIVES: To evaluate the pharmacokinetics of turoctocog alfa in all age groups across clinical trials. PATIENTS/METHODS: Data from previously treated patients with severe hemophilia A (FVIII activity level of ≤ 1%) with no history of FVIII inhibitors, in a non-bleeding state, were included. The pharmacokinetics were assessed following a wash-out period and a subsequent single intravenous 50 IU kg(-1) dose of turoctocog alfa. Blood was sampled during a 48-h period postdose. Standard pharmacokinetic (PK) parameters were estimated on the basis of plasma FVIII activity vs. time (PK profiles) with non-compartmental methods. Furthermore, a population PK analysis was conducted. RESULTS: Data from 76 patients (aged 1-60 years) enrolled globally across six clinical trials were included, totaling 105 turoctocog alfa PK profiles. Single-dose PK results 3-6 months after the first dose of turoctocog alfa were comparable with the results obtained after the first dose. Similar PK characteristics were shown for different lots and strengths of the drug product. Overall, area under the plasma concentration (activity) curve from administration to infinity (AUC) and t1(/2) tended to increase with increasing age, with lower AUC and shorter t(1/2) being seen in children than in adolescents and adults. The PK profiles of turoctocog alfa and other commercially available plasma-derived FVIII and rFVIII products were similar in all age groups. CONCLUSIONS: The PK characteristics of turoctocog alfa have been thoroughly studied, and shown to be consistent over time, reproducible between different lots and strengths of drug product, and similar to those observed for other FVIII products.

Spotlight on the human factor: building a foundation for the future of haemophilia A management: report from a symposium on human recombinant FVIII at the World Federation of Hemophilia World Congress, Melbourne, Australia on 12 May 2014.

Inhibitor development is the most serious and challenging complication in the treatment of severe haemophilia A. Up to 38% of such patients develop inhibitors with current recombinant factor VIII (rFVIII) products produced in hamster cell lines. Human-cl rhFVIII is a new generation fully sulfated B-domain-deleted FVIII coagulant glycoprotein, which is generated from a human cell line. Thus, there are no non-human epitopes which would be potentially immunogenic. This molecule has significantly higher VWF-binding affinity compared with existing full-length rFVIII produced in hamster cell lines. The development aim of Human-cl rhFVIII is to address the challenges of FVIII inhibitors and frequent infusions during prophylaxis. Human-cl rhFVIII's mean half-life is very comparable to some of the newer products which involve modification of the FVIII molecule to extend the circulating half-life. There are promising data concerning the use of a personalized prophylaxis regimen with Human-cl rhFVIII. Preliminary data indicate a median dosing interval of 3.5 days with 66.7% of the patients on a twice per week or fewer infusions schedule combined with a low bleeding rate and no increased FVIII consumption when compared to standard prophylaxis. No product-specific laboratory assay is required to monitor the coagulation activity for Human-cl rhFVIII. The results of registration clinical trials with Human-cl rhFVIII as well as the ongoing studies in previously untreated patients (NuProtect) and personalized prophylaxis study in previously treated patients (NuPreviq), will be discussed. The manufacturer has received marketing authorization for Human-cl rhFVIII in Europe and Canada under the name Nuwiq(®) and plans to launch it in the USA and globally in 2015.

Novel investigations on the protective role of the FVIII/VWF complex in inhibitor development.

Development of inhibitory antibodies to infused factor VIII (FVIII) concentrates is the most serious unresolved complication of haemophilia A treatment. Systematic reviews suggest a twofold higher incidence of inhibitors with recombinant (rFVIII) vs. plasma-derived (pdFVIII) FVIII products, but study methodologies vary widely. The lower immunogenicity of pdFVIII concentrates is believed to derive from the presence of von Willebrand factor (VWF) which acts as protector and chaperone for FVIII. Several novel investigations reinforce the protective role of the VWF/FVIII complex in inhibitor development. At the basic science level, numerous in vitro and in vivo experiments have demonstrated that VWF-containing pdFVIII concentrates (pdFVIII/VWF) provide better protection against inhibitor neutralization than rFVIII products. Conformational aspects of the binding between VWF and FVIII are thought to prevent the 'attack' on FVIII by inhibitory antibodies. VWF/FVIII binding is 100% in pdFVIII products but only 80% in recombinant products and this 'free' FVIII may be a target for inhibitory antibodies. At the clinical level, newer strategies to prevent inhibitor development in previously untreated patients with severe haemophilia are under investigation. The concept of early prophylaxis (before the onset of a bleed) is convincing from a theoretical point of view but requires further evaluation. The Study on Inhibitors in Plasma-Product Exposed Toddlers is specifically addressing the issue of relative immunogenicity between classes of FVIII product (recombinant vs. plasma-derived). Currently nearing its target enrolment of 300 patients, this international randomized controlled trial is expected to provide some definitive answers about this ever-present clinical dilemma.

Atrial fibrillation in patients with haemophilia: a cross-sectional evaluation in Europe.

Atrial fibrillation (AF) is a common health problem in the general population, but data on prevalence or management in patients with haemophilia (PWH) are lacking. The aims of this study were to analyse the prevalence of AF and risk factors for stroke using a cross-sectional pan-European design and to document current anticoagulation practice. The ADVANCE Working Group consists of members from 14 European haemophilia centres. Each centre retrieved data on their PWH with AF. From the total of 3952 adult PWH, 33 had AF with a mean age of 69 years (IQR 62-76). Haemophilia was severe in seven (21%), moderate in six (18%) and mild in 20 (61%) patients. The overall AF prevalence was 0.84% and increased with age; 0.42% in patients 40-60 years and 3.4% in patients >60 years. The mean CHA2 DS2 -Vasc score was 1.3 (range 0-4), predominantly determined by age and hypertension. Hypertension was reported in 48% of PWH with AF. In 11 patients (33%), anticoagulation was started of whom nine aspirin and two vitamin K antagonists. Of these 11 patients, nine had mild haemophilia. Anticoagulation was given in 42% of patients with a CHA2 DS2 -Vasc score ≥2. During follow-up (mean 57 months), there were no thrombotic events reported, nor increases in bleeding severity. The prevalence of AF in haemophilia increases with age and is predominantly present in mild haemophilia. PWH have a low stroke risk based on their CHA2 DS2 -Vasc scores, that might be even lower considering the hypocoagulable state. Only 33% of PWH with AF receives any form of anticoagulation therapy.

[Acquired bleeding disorders - diagnostic approach]. / Abklärung einer erworbenen Blutungsneigung.

BACKGROUND: Patients with acquired bleeding disorders are often a diagnostic challenge in internal medicine. OBJECTIVES: Which diagnostic work up is necessary in these patients and which coagulation tests are useful? MATERIAL AND METHODS: Analysis and diagnostic workup in the daily practice are discussed according to review publications in this field and existing clinical evidence. RESULTS: First important step is the bleeding history of the patient. The different signs of bleeding are important hints for the cause. The global assays Quick (PT) and PTT in combination with platelet count and function reveal a primary knowledge of the kind of the acquired bleeding disorder. In addition special coagulation tests normally lead to the exact diagnosis of the cause of bleeding. CONCLUSIONS: Patients with newly developed bleeding symptoms should be examined for acquired coagulation disorders. The clinical sings in combination with the special coagulation tests allow the correct diagnosis.