RESUMO
INTRODUCTION: Development of inhibitors to human FVIII (hFVIII) significantly complicates the control of bleeding events in patients with haemophilia A. AIM: This prospective, multicentre, open-label, non-comparative, Phase II study evaluated the haemostatic activity of a recombinant B-domain-deleted porcine FVIII (r-pFVIII), in the treatment of non-life/non-limb-threatening bleeding in individuals with haemophilia A and FVIII inhibitors. METHODS: Acute bleeding episodes in patients with pFVIII inhibitor titres <0.8 BU mL-1 were treated with 50 U kg-1 body weight r-pFVIII. Those with pFVIII inhibitor titres of >0.8 BU mL-1 received an initial calculated r-pFVIII loading dose followed by 50 U kg-1 treatment dose. Treatment continued at 6-hourly intervals until bleeding was determined, controlled or till a maximum of eight doses was reached. RESULTS: All 25 bleeding episodes in nine patients (mean age: 23.7 years; range: 14-34 years) were controlled successfully with eight or fewer injections of r-pFVIII. The median time from bleeding onset to the administration of r-pFVIII was 5.7 h (range: 1.5-20.0 h). Twenty of the bleeding episodes (80%) were controlled with one treatment dose of r-pFVIII (with or without a loading dose, median dose: 200.8 U kg-1 ; range: 50-576 U kg-1 ) regardless of pFVIII level. r-pFVIII was well tolerated and no treatment-emergent serious adverse events were considered by the investigator to be related to r-pFVIII administration. CONCLUSION: The results suggest that FVIII replacement therapy with r-pFVIII could be a viable alternative to bypassing agents for the treatment of bleeding episodes in individuals with haemophilia A and FVIII inhibitors.
Assuntos
Hemofilia A/tratamento farmacológico , Hemorragia/tratamento farmacológico , Adolescente , Adulto , Animais , Fator VIII/uso terapêutico , Feminino , Humanos , Masculino , Estudos Prospectivos , Suínos , Adulto JovemRESUMO
Rare bleeding disorders (RBDs) include the hereditary deficiency of fibrinogen, factor (F)II, FV, FV + FVIII, FVII, FX, FXI or FXIII. RBDs do not confer a protective effect against atheromatous plaque formation, and thus the need for cardiovascular (CV) surgery in RBD patients is expected to increase with improved healthcare access (diagnosis and management) and longevity of the population. Clinical data regarding the management of RBDs in this setting are sparse, but the perioperative care team is obliged to gain a better understanding on available biological and pharmacological hemostatic agents. Perioperative management of RBDs in CV surgery is further complicated by heparin anticoagulation, haemodilution, and consumption of procoagulant and anticoagulant proteins associated with cardiopulmonary bypass (CPB). The aims of this review are to summarize pathophysiology of RBDs and laboratory monitoring pertinent to CV surgery, available factor replacement agents, and to provide the framework for perioperative coagulation management of RBD patients.
Assuntos
Transtornos da Coagulação Sanguínea/terapia , Procedimentos Cirúrgicos Cardíacos , Assistência Perioperatória/métodos , HumanosRESUMO
BACKGROUND: Haemophilia care is commonly provided via multidisciplinary specialized management. To date, there has been no systematic assessment of the impact of haemophilia care delivery models on patient-important outcomes. OBJECTIVE: To conduct a systematic review of published studies assessing the effects of the integrated care model for persons with haemophilia (PWH). SEARCH METHODS: We searched MEDLINE, EMBASE and CINAHL up to April 22, 2015, contacted experts in the field, and reviewed reference lists. SELECTION CRITERIA: Randomized and non-randomized studies of PWH or carriers, focusing mainly on the assessment of care models on delivery. DATA COLLECTION AND ANALYSIS: Two investigators independently screened title, abstract, and full text of retrieved articles for inclusion. Risk of bias and overall quality of evidence was assessed using Cochrane's ACROBAT-NRSI tool and GRADE respectively. Relative risks, mean differences, proportions, and means and their variability were calculated as appropriate. RESULTS: 27 non-randomized studies were included: eight comparative and 19 non-comparative studies. We found low- to very low-quality evidence that in comparison to other models of care, integrated care may reduce mortality, hospitalizations and emergency room visits, may lead to fewer missed days of school and work, and may increase knowledge seeking. CONCLUSION: Our comprehensive review found low- to very low-quality evidence from a limited number of non-randomized studies assessing the impact of haemophilia care models on some patient-important outcomes. While the available evidence suggests that adoption of the integrated care model may provide benefit to PWH, further high-quality research in the field is needed.
Assuntos
Gerenciamento Clínico , Hemofilia A/terapia , Modelos de Enfermagem , Ensaios Clínicos como Assunto , Bases de Dados Factuais , Atenção à Saúde/métodos , Atenção à Saúde/normas , Hemofilia A/mortalidade , Hemofilia A/patologia , Humanos , Tempo de InternaçãoRESUMO
This guideline was developed to identify evidence-based best practices in haemophilia care delivery, and discuss the range of care providers and services that are most important to optimize outcomes for persons with haemophilia (PWH) across the United States. The guideline was developed following specific methods described in detail in this supplement and based on the GRADE (Grading of Recommendations, Assessment, Development and Evaluation approach). Direct evidence from published literature and the haemophilia community, as well as indirect evidence from other chronic diseases, were reviewed, synthesized and applied to create evidence-based recommendations. The Guideline panel suggests that the integrated care model be used over non-integrated care models for PWH (conditional recommendation, moderate certainty in the evidence). For PWH with inhibitors and those at high risk for inhibitor development, the same recommendation was graded as strong, with moderate certainty in the evidence. The panel suggests that a haematologist, a specialized haemophilia nurse, a physical therapist, a social worker and round-the-clock access to a specialized coagulation laboratory be part of the integrated care team, over an integrated care team that does not include all of these components (conditional recommendation, very low certainty in the evidence). Based on available evidence, the integrated model of care in its current structure, is suggested for optimal care of PWH. There is a need for further appropriately designed studies that address unanswered questions about specific outcomes and the optimal structure of the integrated care delivery model in haemophilia.
Assuntos
Gerenciamento Clínico , Hemofilia A/terapia , Autoanticorpos/sangue , Atenção à Saúde/métodos , Atenção à Saúde/organização & administração , Atenção à Saúde/normas , Medicina Baseada em Evidências , Hemofilia A/patologia , Humanos , Pesquisa , Fatores de RiscoRESUMO
Haemophilia management is complicated by the extreme variability in laboratory practices. Lack of consistency or comparability in testing makes it difficult to establish diagnostic criteria or disease severity, and complicates response assessment. A global survey was conducted to document current practices. A 35-min survey was completed by 30 laboratory scientists in each of seven countries (France, Germany, Italy, Japan, Spain, UK, USA; 210 in total); results were weighted by average country testing volume in haemophilia. Eighty-three per cent of participants reported participation in a Quality Assurance scheme. Ninety per cent reported using clotting tests in haemophilia A and 88% in haemophilia B (55% and 53% frequent use respectively). Sixty-eight per cent reported chromogenic assays were used in haemophilia A, with only 23% reporting frequent use, compared to only 11% reporting any use in haemophilia B. Twenty-nine separate activated partial thromboplastin time (aPTT) reagents were reported for haemophilia A and 27 aPTT reagents were reported for haemophilia B, with one-quarter or less obtaining reagents or kits from any single manufacturer. Fifty-four per cent run a calibration curve with every factor VIII (FVIII) assay. The mean number of plasma dilutions varied from 2 to 4 for FVIII assays and from 1 to 3 for FIX assays. Results indicate very low consistency in materials and practices used to test for factor activity in haemophilia. A number of responses suggest that some laboratory scientists' understanding of best practices or guidelines in haemophilia could be improved. More education and broader understanding is recommended regarding assay types, assay components, test material and instrument features and capabilities.
Assuntos
Hemofilia A/diagnóstico , Hemofilia B/diagnóstico , Testes de Coagulação Sanguínea/normas , Compostos Cromogênicos/química , Compostos Cromogênicos/metabolismo , Fator IX/análise , Fator IX/normas , Fator VIII/análise , Fator VIII/normas , Hemofilia A/patologia , Humanos , Laboratórios , Tempo de Tromboplastina Parcial , Inquéritos e QuestionáriosRESUMO
Coagulation factor V (FV) deficiency is a rare autosomal recessive bleeding disorder. We investigated a patient with severe FV deficiency (FV:C < 3%) and moderate bleeding symptoms. Thrombin generation experiments showed residual FV expression in the patient's plasma, which was quantified as 0.7 ± 0.3% by a sensitive prothrombinase-based assay. F5 gene sequencing identified a novel missense mutation in exon 4 (c.578G>C, p.Cys193Ser), predicting the abolition of a conserved disulphide bridge, and an apparently synonymous variant in exon 8 (c.1281C>G). The observation that half of the patient's F5 mRNA lacked the last 18 nucleotides of exon 8 prompted us to re-evaluate the c.1281C>G variant for its possible effects on splicing. Bioinformatics sequence analysis predicted that this transversion would activate a cryptic donor splice site and abolish an exonic splicing enhancer. Characterization in a F5 minigene model confirmed that the c.1281C>G variant was responsible for the patient's splicing defect, which could be partially corrected by a mutation-specific morpholino antisense oligonucleotide. The aberrantly spliced F5 mRNA, whose stability was similar to that of the normal mRNA, encoded a putative FV mutant lacking amino acids 427-432. Expression in COS-1 cells indicated that the mutant protein is poorly secreted and not functional. In conclusion, the c.1281C>G mutation, which was predicted to be translationally silent and hence neutral, causes FV deficiency by impairing pre-mRNA splicing. This finding underscores the importance of cDNA analysis for the correct assessment of exonic mutations.
Assuntos
Processamento Alternativo , Deficiência do Fator V/genética , Fator V/genética , Mutação , Animais , Linhagem Celular , Éxons , Deficiência do Fator V/sangue , Deficiência do Fator V/diagnóstico , Expressão Gênica , Humanos , Masculino , Trombina/biossíntese , Adulto JovemRESUMO
Haemophilia therapy is experiencing an unprecedented expansion in the number and novelty of clotting factor concentrates. Every product must be licensed by regulatory authorities, primarily on the basis of its safety and efficacy profiles. The low prevalence of haemophilia, and other inherited bleeding disorders, presents a significant challenge to patient recruitment for preauthorization clinical trials, especially given the low frequency of inhibitory antibodies, the major adverse event related to clotting factor exposure. Other challenges include a lack of harmonization between the major regulatory authorities in certain key areas, the selection of laboratory monitoring methodologies and the difficulty in obtaining high-quality phase IV safety data following authorization. These aspects will be reviewed in this session, which will also highlight the roles played by the World Federation of Hemophilia and International Society on Thrombosis and Haemostasis in the promotion of these discussions.
Assuntos
Fator IX/uso terapêutico , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemofilia B/tratamento farmacológico , Transtornos Herdados da Coagulação Sanguínea/tratamento farmacológico , Fatores de Coagulação Sanguínea/uso terapêutico , Ensaios Clínicos como Assunto , Fator IX/administração & dosagem , Fator IX/efeitos adversos , Fator VIII/administração & dosagem , Fator VIII/efeitos adversos , Humanos , Projetos de Pesquisa , Resultado do TratamentoRESUMO
Given the rarity of haemophilic pseudotumours, consensus on management is lacking. We describe the clinical features and management of haemophilic pseudotumours by retrospectively reviewing the medical records of haemophilia patients with a diagnosis of pseudotumour seen at our Hemophilia Center from 1981 to 2011. We recorded the following data: type and severity of haemophilia, documented aetiological antecedent, localization of the pseudotumour, presenting symptoms, management and outcome. We identified 12 pseudotumours in 11 patients over a 30-year period. Six patients had known inhibitors or a history of inhibitor. An aetiological antecedent leading to the development of pseudotumour was reported in nine cases. Localization of the pseudotumour was confined to soft tissue (n = 3) and bone (n = 8). Six of the 12 pseudotumours (50%) were not diagnosed at the time of initial presentation, with a delay ranging from 6 weeks to 6 years. In eight cases, surgical intervention (surgical drainage, n = 2; excision, n = 4; limb amputation, n = 2) was the initial treatment choice, with complete resolution in six cases. Conservative management with close monitoring occurred in three cases, with one case subsequently requiring surgical resection. We conclude that haemophilic pseudotumours still occur sporadically, and the diagnosis is frequently delayed. Surgical intervention is generally a safe and effective treatment, although conservative management may be appropriate in selected cases.
Assuntos
Hemofilia A/complicações , Hemofilia B/complicações , Neoplasias/diagnóstico , Neoplasias/etiologia , Adulto , Idoso , Amputação Cirúrgica , Diagnóstico Tardio , Drenagem , Embolização Terapêutica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemAssuntos
Desamino Arginina Vasopressina/uso terapêutico , Fator VIII/metabolismo , Hemofilia A/terapia , Hemostáticos/uso terapêutico , Mutação/genética , Adulto , Arginina Vasopressina/análogos & derivados , Fator VIII/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Hemophilia is a rare disorder that is complex to diagnose and to manage. These evidence-based guidelines offer practical recommendations on the diagnosis and general management of hemophilia, as well as the management of complications including musculoskeletal issues, inhibitors, and transfusion-transmitted infections. By compiling these guidelines, the World Federation of Hemophilia aims to assist healthcare providers seeking to initiate and/or maintain hemophilia care programs, encourage practice harmonization around the world and, where recommendations lack adequate evidence, stimulate appropriate studies.
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Fatores de Coagulação Sanguínea/uso terapêutico , Hemofilia A/terapia , Hemorragia/prevenção & controle , Hemostáticos/uso terapêutico , Assistência Integral à Saúde/organização & administração , Atenção à Saúde/organização & administração , Hemofilia A/diagnóstico , Humanos , Manejo da DorRESUMO
The bleeding patterns of severe von Willebrand's disease (VWD) adversely affect quality of life, and may be life threatening. There is a presumed role for prophylaxis with VWF-containing concentrates, but data are scarce. The von Willebrand Disease Prophylaxis Network (VWD PN) was formed to investigate the role of prophylaxis in clinically severe VWD that is not responsive to other treatment(s).Using a retrospective design, the effect of prophylaxis was studied. Availability of records to document, or reliably assess, the type and frequency of bleeding episodes prior to, and after, the initiation of prophylaxis was required. Annualized bleeding rates were calculated for the period prior to prophylaxis, during prophylaxis and by primary bleeding indication defined as the site accounting for more than half of all bleeding symptoms. The Wilcoxon signed-rank test of differences in the medians was used. Sixty-one subjects from 20 centres in 10 countries were enrolled. Data for 59 were used in the analysis. The median age at onset of prophylaxis was 22.4 years. Type 3 VWD accounted for the largest number (N = 34, 57.6%). Differences in bleeding rates within individuals during compared with before prophylaxis were significant for the total group (P < 0.0001), and for those with primary bleeding indications of epistaxis (P = 0.0005), joint bleeding (P = 0.002) and GI bleeding (P = 0.001). The effect of prophylaxis was similar among those age < 18 years and those ≥ 18. One person developed an inhibitor during treatment. We conclude that prophylactic treatment of VWD is efficacious.
Assuntos
Coagulantes/uso terapêutico , Hemorragia/prevenção & controle , Doenças de von Willebrand/tratamento farmacológico , Fator de von Willebrand/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Hemartrose/etiologia , Hemartrose/prevenção & controle , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem , Doenças de von Willebrand/complicaçõesRESUMO
Rare disease research is increasingly challenging. For those with haemophilia, this is an exciting time, with the promise of new therapies at the bench and in early phase clinical trials. Yet, it is also a time for critical assessment and planning to assure the success of the clinical research effort. As successes at the bench have enabled transition of novel peptides, longer-acting factor products and gene therapy to clinical trials, clinicians face the challenges of limited number of patients, competing priorities and strained resources. To solve these problems and assure the success of the clinical research effort, it is essential that the research process be enabling and the dialogue be global, involving academia with industry, and physicians with patients. This is a critical juncture in the process, especially with new national initiatives in clinical research at hand. Needs must be assessed and priorities must be set to assure that despite the challenges, exciting new therapies will ultimately translate into safe, effective therapies for patients. Finally, these challenges are by no means restricted only to rare disease research. With the evolution of genetic medicine, it is likely that the general medical disease research of the future will include small clinical trials of new agents for small subsets of patients with certain disease mutations. Thus, the milestones we achieve in this ongoing process will hopefully not only enable clinical trials research in a rare disease, but also in many medical genetic disease of the future.
Assuntos
Pesquisa Biomédica , Hemofilia A , Hemofilia B , Doenças Raras , Hemofilia A/genética , Hemofilia A/terapia , Hemofilia B/genética , Hemofilia B/terapia , Humanos , Doenças Raras/genética , Doenças Raras/terapiaRESUMO
OBI-1 is a recombinant B-domain deleted porcine factor VIII (FVIII). FVIII treatment in those with haemophilia A may be complicated by the development of anti-FVIII antibodies (inhibitors) leading to a failure to respond to treatment with human FVIII. To compare the pharmacokinetics and safety of a single dose of OBI-1 with Hyate:C in subjects with haemophilia A and inhibitors, subjects were randomized to receive either Hyate:C followed by placebo or placebo followed by OBI-1 in a double-blind fashion. FVIII levels were assayed using both a one-stage coagulation assay (OSCA) and chromogenic assay. Pharmacokinetic parameters for FVIII were calculated for 6/9 subjects randomized; in three subjects baseline anti-porcine FVIII inhibitors led to a lack of measurable FVIII activity. Mean C(max) appeared higher for OBI-1 (OSCA: 176.00 U dL(-1), standard deviation ± 88.00; chromogenic: 151.00 ± 31.51 U dL(-1)) than Hyate:C (OSCA: 82.3 ± 19.22 U dL(-1); chromogenic: 52.67 ± 13.8 U dL(-1)). Mean AUC also appeared higher for OBI-1 (OSCA: 2082.87 ± 1323.43 U h(-1) dL(-1) ; chromogenic: 1817.28 ± 625.14 U h(-1) dL(-1)) than Hyate:C (OSCA: 1177.8 ± 469.49 U h(-1) dL(-1); chromogenic: 707.61 ± 420.05 U h(-1) dL(-1)). Two infusion-related events occurred: one with Hyate:C, one with placebo. Four of five subjects without anti-porcine FVIII inhibitors at baseline remained porcine FVIII inhibitor negative 29 days after infusion. A single dose of OBI-1 appears to have higher bioavailability than Hyate:C in subjects with haemophilia A without measurable anti-porcine FVIII inhibitors, and is well tolerated. These results should be confirmed in a larger phase 2/3 study.
Assuntos
Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Hemofilia A/terapia , Adolescente , Adulto , Animais , Inibidores dos Fatores de Coagulação Sanguínea/sangue , Fator VIII/efeitos adversos , Fator VIII/antagonistas & inibidores , Hemofilia A/sangue , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/efeitos adversos , Fragmentos de Peptídeos/farmacocinética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Suínos , Adulto JovemRESUMO
SUMMARY: While the majority of this session will deal with selected inherited vascular abnormalities that may manifest as a haemorrhagic disorder, the initial discussion by Dr Key will focus on the interplay between the vessel wall and components of the coagulation system, with a focus on haemophilia A and B. Although it is generally accepted that physiological haemostasis is triggered by contact of blood with tissue factor (TF), there remains some controversy regarding the cellular origin of TF in vivo. In addition, the initiation and propagation of thrombin generation are highly dependent on the balance of pro- and anticoagulant functions of endothelium, a profile that varies significantly throughout the vasculature. Drs De Paepe and Malfait address heritable collagen disorders such as the Ehlers-Danlos syndromes (EDS), a heterogeneous group of diseases involving the skin, ligaments and joints, blood vessels and internal organs. Most EDS subtypes are caused by mutations in genes encoding fibrillar collagens, or in genes coding for enzymes involved in posttranslational modifications of collagens. Accurate biochemical and molecular testing is now available for most EDS subtypes and can direct genetic counselling and medical management for these disorders. Dr Shovlin reviews recent developments in hereditary haemorrhagic telengiectasia (HHT), a frequently undiagnosed disorder characterized by arteriovenous malformations in multiple organs. These abnormal blood vessels are the result of mutations in one of a number of genes whose protein products influence TGF-beta signalling in vascular endothelial cells. Several HHT management guidelines have been published and are discussed.
Assuntos
Doenças do Colágeno/fisiopatologia , Síndrome de Ehlers-Danlos/fisiopatologia , Hemofilia A/complicações , Hemofilia B/complicações , Hemostasia , Colágeno/metabolismo , Diagnóstico Diferencial , Síndrome de Ehlers-Danlos/diagnóstico , Células Endoteliais/fisiologia , Endotélio/fisiologia , Epistaxe/genética , HumanosAssuntos
Inibidores dos Fatores de Coagulação Sanguínea/sangue , Fator VIII/imunologia , Adulto , Idoso , Análise por Conglomerados , Demografia , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemofilia A/patologia , Humanos , Masculino , Razão de Chances , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , Adulto JovemRESUMO
We used data collected as part of the Universal Data Collection (UDC) surveillance project in haemophilia treatment centers (HTC) to study the incidence, risk factors and impact of septic arthritis among males with haemophilia. Patients participating in UDC on two or more occasions were included. Cases were defined as patients with documented joint infection. Characteristics of the cases were compared with those of haemophilia patients without infection. Among the 8026 eligible patients with 36 015 person-years of follow-up, 30 (0.37%) had a documented joint infection (incidence rate 83 per 100 000 person-years). In a logistic regression model, only increasing age (OR = 6.1 for age > or =30), race/ethnicity other than white (OR = 3.9), presence of inhibitor (OR = 3.9), invasive procedure in the past year (OR = 2.7) and presence of one or more target joints (OR = 3.2) remained statistically significant. Central venous access devices use and hepatitis C virus and HIV infection were not associated with septic arthritis risk after adjusting for potential confounders. Study limitations include possible underestimation of septic arthritis rate in this population and its retrospective design. We conclude that septic arthritis is an uncommon complication of haemophilia occurring primarily in joints most affected by bleeding and reparative surgical interventions.