Production of high-potency concentrates of antihemophilic globulin in a closed-bag system

Joint health and pain in the changing hemophilia treatment landscape

INTRODUCTION

Hemophilia is an inherited bleeding disorder. Bleeding, and in particular joint hemorrhage results in chronic arthropathy and disability. Acute and chronic pain are frequent and limit activity and participation and result in decreased health-related quality of life. Remarkable progress has been made in the diagnosis and treatment of hemophilia but bleeding continues to prove recalcitrant to currently available treatments and joint disease remains problematic. Physiotherapy and pain management are mainstays of current multidisciplinary integrated care of people with hemophilia (PWH). The focus of this review is on preservation of joint health in the era of new and innovative therapies.

AREAS COVERED

A search of the PubMed Central was conducted on 1 February 2024 using the MeSH Major Topic terms identified as keywords for the manuscript. This review will highlight what is known and unknown about joint bleeding and arthropathy, including insights on pain as a related complication.

EXPERT OPINION

Recent advances in therapeutic interventions aimed at promoting healthy joints in PWH will be discussed, including both the pharmacological treatment landscape and related strategies to promote joint health.

Hemostatic capability of ultrafiltrated fresh frozen plasma compared to cryoprecipitate

This in vitro study evaluated the potential hemostatic effect of fresh frozen plasma (FFP) ultrafiltration on clotting factors, coagulation parameters, and plasma properties. ABO-specific units of FFP (n = 40) were prepared for the concentrated FFP and cryoprecipitate. Plasma water was removed from FFP by ultrafiltration using a dialyzer with a pump running at a 300 mL/min. The aliquot of each concentrated FFP after 50, 100, 200, and 250 mL of fluid removal were measured the standard coagulation assay, clotting activity, and plasma properties to compare those parameters of cryoprecipitate. Concentrated FFP contained 36.5% of fibrinogen in FFP with a mean concentration of 7.2 g/L, lower than the cryoprecipitate level. The levels of factor VIII (FVIII), von Willebrand factor (VWF):antigen (Ag), and VWF:ristocetin cofactor (RCo) were also lower in concentrated FFP, whereas the levels of factor V, factor IX, factor XIII, antithrombin and albumin was higher in concentrated FFP. Maximum clot firmness (MCF) in thromboelastometry was approximately one-half of that in cryoprecipitate. Although the levels of VWF:Ag, VWF:RCo, and FVIII differed depending on the ABO blood types, fibrinogen levels, and MCF were not significantly different among the ABO blood groups in FFP and concentrated FFP.

Damoctocog Alfa Pegol for Hemophilia A Prophylaxis: An Italian Multicenter Survey

Hemophilia A is characterized by a deficiency of clotting factor VIII (FVIII) requiring lifelong prophylactic treatment, typically with recombinant FVIII. In recent years, drugs with extended half-lives have become available, including damoctocog alfa pegol (Bayer S.p.A.). The clinical efficacy and safety of damoctocog alfa pegol were demonstrated in the PROTECT VIII phase II/III development program. To assess the physicians' experience and to collect data on prophylactic treatment with damoctocog alfa pegol, a monitoring survey was carried out among 15 Italian hemophilia centers. A total of 149 patients on treatment with damoctocog alfa pegol for at least 6 months were considered. Zero bleeds were reported in 75% of patients treated with damoctocog alfa pegol in the last 6 months; zero hemarthroses were reported in 82% of the same patients. Overall, 86% of patients with damoctocog alfa pegol reduced their monthly infusions. The estimated average reduction in IU/kg during prophylaxis with damoctocog alfa pegol, both monthly and annually, was around 17.5%. All involved clinicians were satisfied with damoctocog alfa pegol. Survey results suggest that damoctocog alfa pegol reduced the number of weekly infusions, annual bleeding, and joint bleeding rate in the majority of patients, improving joint health and patients' quality of life.

Hemophilia treatment innovation: 50 years of progress and more to come

With the goal of emphasizing the striking advances that materialized in hemophilia care particularly in the last 10 years, the progress of knowledge that started from the 1970s will first be sketched as background. Subsequently, the unmet needs pertaining to therapeutic adherence and thus to prophylaxis effectiveness led to the availability of factor VIII and IX products with an extended plasma half-life as well as to emicizumab, the first nonfactor medicine for subcutaneous administration in patients with hemophilia A with or without inhibitor. The issue of a still lacking cure for the disease is approached by means of gene therapy, the first products of which were approved in 2022 for adults with both hemophilia types. Finally, views will be offered on further progress that is expected in the next few years and how patients and their care providers may make personalized choices among the wide array of therapeutic options.

Hepatitis C Virus Infections in Patients with Hemophilia: Links, Risks and Management

Haemophilia is a rare, hereditary bleeding disorder. Clotting factor concentrates were a revolutionary treatment which changed the life of people with haemophilia. However, early generation of clotting factor concentrates, without viral inactivation procedures in the manufacturing process, led to an increased risk of transmission of blood-borne viral infections, mainly due to hepatitis C virus and human immunodeficiency virus. As only 20% of HCV-infected patients clear the infection naturally, chronic HCV infection constitutes a serious health problem and a major cause of chronic liver disease in this group of patients. Fortunately, the use of viral inactivation procedures in the plasma-derived factor concentrates manufacturing process and the availability of alternative treatment options, led to a significant reduction of transfusion-associated viral infections. The advent of multiple, orally administrated, highly effective direct-acting antivirals (DAAs) is changing the natural history of HCV infection in patients with haemophilia as these drugs have an excellent safety profile and achieve very high sustained virological response rates, similar to the general population. Eradication of HCV-infection in patients with haemophilia is feasible via micro-elimination projects.

The More Recent History of Hemophilia Treatment

The availability first in the 1970s of plasma-derived and then in the 1990s of recombinant clotting factor concentrates represented a milestone in hemophilia care, enabling not only treatment of episodic bleeding events but also implementation of prophylactic regimens. The treatment of hemophilia has recently reached new landmarks. The traditional clotting factor replacement therapy for hemophilia has been substituted over the last 10 years by novel treatments such as bioengineered factor VIII and IX molecules with extended half-life and non-factor treatments including the bispecific antibody emicizumab. This narrative review is dedicated to these newer therapies, which are contributing significantly to improving the long-term management of prophylaxis in hemophilia patients. Another section is focused on the current state of gene therapy, which is a promising definitive cure for severe hemophilia A and B.

Past, present and future of orthopedic surgery in hemophilia: looking to a world without bleeding and arthropathy in the near future

INTRODUCTION

The purpose of this article is to review the literature on orthopedic surgery in people with hemophilia (PWH), to better understand its past and present and attempt to predict the future.

AREAS COVERED

A Cochrane Library and PubMed (MEDLINE) search of studies related to orthopedic surgery in PWH was analyzed. A downward trend in orthopedic surgery in PWH has been observed. Patients on continuous prophylaxis are less likely to require orthopedic surgery. In patients with hemophilia, the risk of major bleeding remains high after total joint arthroplasty, even with factor replacement. Cases of acute compartment syndrome, pseudotumors and even limb amputations are still observed in PWH.

EXPERT OPINION

Orthopedic surgery for PWH should always be performed in specialized centers with multidisciplinary expertise in the correct management of hemophilia. It is paramount to perform an accurate preoperative coagulation screening before surgery. The availability of prophylaxis through replacement and the recent non-replacement therapy in the well-developed countries will diminish substantially or hopefully abolish completely the need for surgery in the treatment of PWH. Therefore, we are looking to a world without bleeding and arthropathy in the next future. Unfortunately, this is not true for the under-development countries.

The legacy of haemophilia: Memories and reflections from three survivors

Following the publication of a book of personal memories by one of us (CS^1,2), we have attempted to synthesis our joint memories of three ageing men, born in the era preceding universal access to treatment, in an attempt to describe our experience, our challenges and our reflections on the development of therapies, which have ensured that our experience of growing up with haemophilia in the 1950s and 1960s has not been mirrored by the current generation of patients. We describe our upbringing in different parts of Europe in health care systems which, while of varying standards, were all unable to offer the kind of care which developed after the development of specific therapies. We assess the effect of the contamination of these therapies by blood‐borne pathogens on our own development, and the development of our communities around us. In addition, we reflect on the lessons learnt, sometimes painfully, by our generation of people with haemophilia and how some of these enabled us to overcome substantial hurdles, survive and build productive lives. Finally, we survey the development of therapies in the past 20 years, and offer some reflections on how our experience can be integrated in a realistic expectation of what the future holds for our community, in our own affluent societies and in countries less advantaged economically. We hope that our thoughts may contribute to continued progress in the field of haemophilia care.

Impact of novel hemophilia therapies around the world

Hemophilia A and B are hereditary bleeding disorders, characterized by factor VIII or IX deficiencies, respectively. For many decades, prophylaxis with coagulation factor concentrates (replacement therapy) was the standard‐of‐care approach in hemophilia. Since the 1950s, when prophylaxis started, factor concentrates have been improved with virus inactivation and molecule modification to extend its half‐life. The past years have brought an intense revolution in hemophilia care, with the development of nonfactor therapy and gene therapy. Emicizumab is the first and only nonreplacement agent to be licensed for prophylaxis in people with hemophilia A, and real‐world data show similar efficacy and safety from the pivotal studies. Other nonreplacement agents and gene therapy have ongoing studies with promising results. Innovative approaches, like subcutaneous factor VIII and lipid nanoparticles, are in the preclinical phase. These novel agents, such as extended half‐life concentrates and emicizumab, have been available in resource‐constrained countries through the constant efforts of the World Federation of Haemophilia Humanitarian Aid Program. Despite the wide range of new approaches and therapies, the main challenge remains the same: to guarantee treatment for all. In this article, we discuss the evolution of hemophilia care, global access to hemophilia treatment, and the current and future strategies that are now under development. Finally, we summarize relevant new data on this topic presented at the ISTH 2021 virtual congress.

Spinal epidural hematoma in a child with hemophilia A with high titer inhibitors and follow-up with prophylactic emicizumab: case report and literature review

Hemorrhage in the central nervous system is the most severe and debilitating manifestation affecting patients with hemophilia A. The spinal epidural space is the most unusual and clinically challenging site of central nervous system hemorrhage in hemophilia A. These patients often show insidious neurological signs and symptoms that delay diagnosis and treatment. We share our experience treating a 4-year-old male patient with severe hemophilia A and high titer inhibitors with a spontaneous spinal epidural hematoma. The patient presented initially with intense headache and neck pain. After blood tests and imaging studies, bypassing agent therapy with recombinant-activated factor VII was used until discharge; this was later replaced with emicizumab. After 18 months, the patient is without neurological sequelae and has not experienced subsequent bleeding episodes. We review the available literature and discuss the relevance of emicizumab compared with standard therapies in the context of spontaneous spinal epidural hematoma.

Recent Advances in the Treatment of Hemophilia: A Review

Progress in hemophilia therapy has been remarkable in the first 20 years of the third millennium, but the innovation began with the description the fractionation of plasma in 1946. The first concentrates followed the discovery of FVIII in the cryoprecipitate of frozen plasma and FIX in the supernatant in the early 1960s, which led to the initial attempts at replacement therapy. Unfortunately, the lack of screening methods for viral pathogens resulted in people with hemophilia (PWH) receiving concentrates contaminated by hepatitis A virus, hepatitis C virus, and human immunodeficiency virus, as these concentrates were made from large industrial pools of plasma derived from thousands of donors. Fortunately, by 1985, viral screening methods and proper virucidal techniques were developed that made concentrates safe. Increasingly pure products followed the introduction of chromatography steps with monoclonal antibodies in the production process. The problem of immunogenicity of exogenously administered concentrates has not yet had a complete solution. The development of alloantibodies against FVIII in about 25-35% of PWH is the most serious adverse effect of replacement therapy. The next major advance followed the cloning of the F8 gene and later the F9 genes, which paved the way to produce concentrates of factors obtained by the recombinant DNA technology. The injected FVIII and FIX molecules had a relatively short circulating half-life in the plasma of people with hemophilia A and B, approximately 12 and 18 hours, respectively. The ability to prolong the plasma half-life and extend the interval between injections followed the application of methods to conjugate the factor molecule with the fragment crystallizable of IgG1 or albumin or by adding polyethylene glycol, which has led to an increase in the half-life of concentrates, especially for rFIX. The next frontier in hemophilia therapy is the application of durable and potentially curative therapies such as with gene addition therapy. Experiments in hemophilia B have demonstrated durable responses. Unfortunately, the results with gene therapy for hemophilia A have not been as remarkable and the durability must still be demonstrated. Nonetheless, the long-term safety, predictability, durability, and efficacy of gene therapy for hemophilia A and B remain an open question. At present, only healthy adult PWH have been enrolled in gene therapy clinical trials. The application of gene therapy to children and those with pre-existing antibodies against the delivery vector must also be studied before this therapy becomes widespread.

MRI predicts 5-year joint bleeding and development of arthropathy on radiographs in hemophilia

Magnetic resonance imaging (MRI) is considered as the reference standard to assess early joint changes in hemophilia. However, the clinical relevance of MRI findings is still unknown. The aim of this prospective study was to assess the predictive value of MRI for 5-year joint bleeding and progression of arthropathy in patients with hemophilia. Both knees and ankles of patients with hemophilia and absent or limited arthropathy on radiographs were assessed by using MRI and radiographs. MRI scans were scored according to the International Prophylaxis Study Group MRI score for hemophilic arthropathy. Patients were followed up for 5 years, including assessment of joint bleeding and repeated radiographic assessment. Associations between baseline MRI findings with 5-year bleeding and progression of arthropathy were expressed as odds ratios (OR), adjusted for severity of disease and joint bleeding history. Baseline assessment included 104 joints of 26 patients with hemophilia (median age, 21 years). Four ankles with severe joint changes were excluded. Follow-up was available for 96 (92%) of 104 joints. During 5 years of follow-up, bleeding was reported for 36% of joints. Five-year bleeding was significantly increased in joints with synovial hypertrophy at 80% vs 27% in joints without synovial hypertrophy (OR, 10.1; 95% confidence interval, 3.4-31.3). In joints with normal baseline radiographs, any osteochondral or synovial changes on MRI were associated with radiographic changes 5 years later (positive predictive value, 75%; negative predictive value, 98%). Joints with synovial hypertrophy on MRI had a significantly higher chance of 5-year bleeding. All MRI changes, except effusion, were strong predictors for development of arthropathy on radiographs.

Viral hepatitis in haemophilia: historical perspective and current management

The introduction of clotting factor concentrates has substantially improved the lives of people with clotting factor deficiencies. Unfortunately, the transmission of blood-borne viral infections through these plasma-derived products led to a huge epidemic of human immunodeficiency virus and viral hepatitis in people with haemophilia (PWH). In a significant proportion of PWH exposed to these viruses, the ensuing decades-long chronic infection resulted in excess morbidity and mortality. Fortunately, developments in the safety of blood products, as well as vaccination and highly effective antiviral treatments have improved the prospects of PWH. The present article reviews the background of the viral hepatitis epidemic in PWH, the natural history of hepatitis B and C infections and their long-term management.

A novel modified thaw-siphon method for extracting cryoprecipitate: The Bokutoh-siphon method

BACKGROUND

Cryoprecipitate (CRYO) is neither produced nor supplied by the Japanese Red Cross Society. A novel CRYO extraction method established in-house by modifying a thaw-siphon technique was demonstrated in this study.

STUDY DESIGN AND METHODS

A pack of fresh frozen plasma was thawed and equally divided into two bags for CRYO extraction by different methods. CRYO was extracted from the blood plasma using a standard centrifugation method and our modified thaw-siphon method (Bokutoh-siphon method; B method). The two different CRYOs extracted were analyzed to compare the differences in the amount of fibrinogen recovered, clotting factors extracted, and clotting activity.

RESULTS

The amount of fibrinogen in the CRYO extracted using the B-siphon method was similar to that obtained using the standard method (recovery of fibrinogen: B-siphon method: 71.2% vs. standard method: 61.0%). The amount of clotting XIII factor extracted using the B-siphon method was significantly lower than those extracted using the standard method. On the other hand, clotting II, V factors, and C1q esterase inhibitor not concentrated in CRYO content from the B-siphon method were significantly higher than that from the standard method.

CONCLUSION

A new in-house CRYO preparation method was established by modifying a previously used thaw-siphon method. A coagulation factor-rich CRYO was extracted from plasma frozen at -40°C along with the first fraction of thawed plasma, without using a large-capacity refrigerated centrifuge for blood bags.

The German Hemophilia Registry: Growing with Its Tasks

Hemophilia is a rare heredity bleeding disorder that requires treatment for life. While few therapeutic options were available in the past, multiple recent breakthroughs have fundamentally altered and diversified hemophilia therapy, with even more new therapeutic options forthcoming. These changes are mirrored by significant regulatory and legal changes, which have redefined the role of hemophilia registries in the European Union (EU). This dual paradigm shift poses new regulatory, scientific but also structural requirements for hemophilia registries. The aim of this manuscript is to enumerate these significant challenges and to demonstrate their incorporation into the redesign of the German Hemophilia Registry (Deutsches Hämophilieregister, dhr). To identify the spectrum of hemophilia therapies and the degree of regulatory changes, a horizon screening was performed. Consequently, a core dataset for the dhr was defined by harmonization with regulatory guidelines as well as other hemophilia registries and by heeding the needs of different stakeholders (patients, clinicians, regulators, and scientists). Based on this information, a new registry structure was established, which is optimized for capturing data on new and established hemophilia therapies in a changing therapeutic and regulatory landscape.

FVIII Immunogenicity-Bioinformatic Approaches to Evaluate Inhibitor Risk in Non-severe Hemophilia A

The life-long inhibitor risk in non-severe hemophilia A has been an important clinical and research focus in recent years. Non-severe hemophilia A is most commonly caused by point mutation, missense F8 genotypes, of which over 500 variants are described. The immunogenic potential of just a single amino acid change within a complex 2,332 amino acid protein is an important reminder of the challenges of protein replacement therapies in diverse, global populations. Although some F8 genotypes have been identified as "high risk" mutations in non-severe hemophilia A (e.g., R593C), this is likely, in part at least, a reporting bias and oversimplification of the underlying immunological mechanism. Bioinformatic approaches offer a strategy to dissect the contribution of F8 genotype in the context of the wider HLA diversity through which antigenic peptides will necessarily be presented. Extensive modeling of all permutations of FVIII-derived fifteen-mer peptides straddling all reported F8 genotype positions demonstrate the likely heterogeneity of peptide binding affinity to different HLA II grooves. For the majority of F8 genotypes it is evident that inhibitor risk prediction is dependent on the combination of F8 genotype and available HLA II. Only a minority of FVIII-derived peptides are predicted to bind to all candidate HLA molecules. In silico predictions still over call the risk of inhibitor occurrence, suggestive of mechanisms of "protection" against clinically meaningful inhibitor events. The structural homology between FVIII and FV provides an attractive mechanism by which some F8 genotypes may be afforded co-incidental tolerance through homology of FV and FVIII primary amino sequence. In silico strategies enable the extension of this hypothesis to analyse the extent to which co-incidental cross-matching exists between FVIII-derived primary peptide sequences and any other protein in the entire human proteome and thus potential central tolerance. This review of complimentary in vitro, in silico, and clinical epidemiology data documents incremental insights into immunological mechanism of inhibitor occurrence in non-severe hemophilia A over the last decade. However, complex questions remain about antigenic processing and presentation to truly understand and predict an individual person with hemophilia risk of inhibitor occurrence.

"Whatever Works": Innovations in the Treatment of Hemophilia in the United States 1783-1950

Treatment of the bleeding disorder hemophilia in the nineteenth century was empirical, based on clinical experience. Medications, transfusions of human or animal blood, and injections of blood sera were utilized in an attempt to halt life-threatening hemorrhages. After 1900, the application of clinical laboratory science facilitated the utilization of anti-coagulated blood and donor blood compatibility tests for safer emergency transfusions. But repeated transfusions produced blood incompatibility that limited future utilization. Investigation of hormones and snake venom as coagulants appeared hopeful during the 1930s, but plasma globulin research during World War II resulted in the isolation of antihemophilic factors that promptly reduced hemorrhage. Their application to bleeding episodes resulted in a more normal life for hemophiliacs after 1950.

Factor VIII: the protein, cloning its gene, synthetic factor and now - 35 years later - gene therapy; what happened in between?

The foundation of haemophilia A therapy in the last 35 years has been critically dependent on isolation of the Factor VIII (FVIII) protein and discovery of the cDNA sequence of the FVIII gene, published in 1984. Identification of the FVIII sequence resulted in a new era of recombinant concentrates and led to significant improvements in safety, set against the tragedy of widespread HIV and hepatitis infections in haemophilia patients from contaminated plasma-based products. We chronicle the scientific methods and race leading up to the publication of the FVIII DNA sequence and the legacy that follows through to revolutionary gene therapy treatment in clinical trials today.

Healthcare professionals in the 'tainted blood' era in Canada: Their forgotten emotions

INTRODUCTION

During the 1970s and early 1980s, Canada's comprehensive care haemophilic programs were established. Newer therapies led to a rapid increase in quality of life and expected life span for persons with haemophilia (PWH). The outlook was bright. However, beginning in 1982, the appearance of HIV/AIDS transmitted by treatment products led to the 'tainted blood' era with its devastating impact on PWH, recently highlighted in the Canadian Broadcasting Corporation mini-series 'Unspeakable'. What has received less notice is how the healthcare professionals (HCP) managing these patients then were affected.

AIM

To report the emotional effects of that era on HCPs.

METHODS

In developing an oral history of haemophilic care in Canada we have interviewed 76 HCPs, the majority of whom had worked in haemophilic clinics during that era. During each interview, we asked the interviewee to reflect on what this did to haemophilic care and to him/herself. The interview responses were analysed.

RESULTS

HCPs have been markedly affected by the events of the 1980s with feelings that persist more than 30 years later. Most related to the loss of so many of their patients and the inability to alter the rapidly changing course of events at the time.

CONCLUSION

The 'tainted blood' era had persistent strong emotional effects on HCPs. They were helpless to stop or to mitigate the devastating epidemics. Wellness support programs were less well developed then. While the focus is in the Canadian context, we suggest that a parallel can be drawn within haemophilic communities in other countries.

Critical Evaluation of Strategies for the Production of Blood Coagulation Factors in Plant-Based Systems

The use of plants as production platforms for pharmaceutical proteins has been on the rise for the past two decades. The first marketed plant-made pharmaceutical, taliglucerase alfa against Gaucher's disease produced in carrot cells by Pfizer/Protalix Biotherapeutics, was approved by the US Food and Drug Administration (FDA) in 2012. The advantages of plant systems are low cost and highly scalable biomass production compared to the fermentation systems, safety compared with other expression systems, as plant-based systems do not produce endotoxins, and the ability to perform complex eukaryotic post-translational modifications, e.g., N-glycosylation that can be further engineered to achieve humanized N-glycan structures. Although bleeding disorders affect only a small portion of the world population, costs of clotting factor concentrates impose a high financial burden on patients and healthcare systems. The majority of patients, ∼75% in the case of hemophilia, have no access to an adequate treatment. The necessity of large-scale and less expensive production of human blood coagulation factors, particularly factors associated with rare bleeding disorders, may be an important area for plant-based systems, as coagulation factors do not fit into the industry-favored production models. In this review, we explore previous studies on recombinant production of coagulation Factor II, VIII, IX, and XIII in different plant species. Production of bioactive FII and FIX in plants was not achieved yet due to complex post-translational modifications, including vitamin K-dependent γ-carboxylation and propeptide removal. Although plant-made FVIII and FXIII showed specific activities, there are no follow-up studies like pre-clinical/clinical trials. Significant progress has been achieved in oral delivery of bioencapsulated FVIII and FIX to induce immune tolerance in murine models of hemophilia A and B, resp. Potential strategies to overcome bottlenecks in the production systems are also addressed in this review.

Influence of canine donor plasma hemostatic protein concentration on quality of cryoprecipitate

BACKGROUND

Cryoprecipitate (CRYO) is a plasma component containing high concentrations of factor VIII (FVIII), von Willebrand factor (VWF), and fibrinogen. Because Greyhounds are reported to have lower plasma VWF and fibrinogen concentrations, their plasma may not yield high potency CRYO.

OBJECTIVES

To determine if plasma hemostatic protein concentration is a good predictor of CRYO potency and if a difference exists in quality of CRYO prepared from Greyhounds versus non-Greyhounds.

ANIMALS

Twenty Greyhounds and 20 non-Greyhounds.

METHODS

A 450 mL unit of blood was collected from each donor, centrifuged to prepare fresh frozen plasma (FFP), and processed to CRYO. Aliquots of FFP and CRYO were analyzed for FVIII, VWF, and fibrinogen content and factor recovery.

RESULTS

A positive correlation was found among donor plasma FVIII, VWF and fibrinogen concentration, and CRYO factor content (P < .001). Mean recovery was highest for VWF (67%), followed by fibrinogen (47%), and FVIII (37%). No breed difference was found in mean CRYO FVIII content, but CRYO VWF and fibrinogen were lower in Greyhounds (P = .004 and P < .001, respectively). No difference was found between Greyhounds and non-Greyhounds for the number of CRYO units meeting human blood banking standards.

CONCLUSIONS AND CLINICAL IMPORTANCE

Factor concentration in FFP is associated with CRYO potency, suggesting that prescreening of blood donors may enhance CRYO quality. Despite lower VWF and fibrinogen content, CRYO prepared from Greyhounds is acceptable based on blood banking standards for humans, indicating that Greyhound FFP does not need to be excluded from CRYO production.

The role of emicizumab, a bispecific factor IXa- and factor X-directed antibody, for the prevention of bleeding episodes in patients with hemophilia A

Hemophilia A, characterized by impaired or absent expression of factor VIII, has long been managed via direct factor replacement. Functionally, factor VIII acts as a cofactor for factor IXa and allows activation of factor X, which, in combination with factor V, generates thrombin. Bispecific antibodies such as emicizumab are recombinant, monoclonal antibodies capable of recognizing and binding to two distinct antigenic targets simultaneously; emicizumab binds factors IXa and X, resulting in spatial approximation and activation of factor X, thereby mimicking the actions of factor VIII. Critically, the presence of antifactor VIII antibodies, for example, inhibitors, impacts neither the mechanism nor the efficacy by which emicizumab functions. The results and interim analyses of the emicizumab clinical trials, HAVEN 1, 2, 3, and 4, are additionally reviewed and discussed.

Do we still need cryoprecipitate? Cryoprecipitate and fibrinogen concentrate as treatments for major hemorrhage - how do they compare?

INTRODUCTION

Major hemorrhage is a source of significant mortality and morbidity worldwide. Identification and characterization of coagulation impairment associated with major hemorrhage has suggested a key role for fibrinogen deficiency, however the optimum mode of replacement of fibrinogen remains unclear, and standardized major hemorrhage protocols may overlook context-dependent variations in individual patients' clotting derangement. Areas covered: This paper examines the current practice and evidence regarding the role of different modes of fibrinogen replacement in major hemorrhage in 3 distinct clinical settings: trauma, obstetric hemorrhage, and gastrointestinal hemorrhage with associated liver disease. A literature search was carried out electronically using Athens access to the National Health Service evidence health information resources, primarily PubMed and Google Scholar. Expert commentary: Two key questions need to be addressed. First, what is the role of concentrated fibrinogen (by comparison to no fibrinogen), and second, which concentrated source or product is more effective (or cost-effective)? Current practice and concept is derived largely from small pilot trials in the trauma setting, but results from larger studies are awaited. More comparative data on changes to clotting profiles in different groups of bleeding patients are needed to help delineate differences and guide interventional treatment studies.

A contemporary look at FVIII inhibitor development: still a great influence on the evolution of hemophilia therapies

INTRODUCTION

The development of inhibitors against factor VIII (FVIII) replacement therapy remains the most important challenge for clinicians in the treatment of hemophilia patients. This review focusses on risk factors and management of FVIII inhibitors, particularly in light of SIPPET study findings and subsequent analyses. Areas covered: A brief history and evolution of hemophilia therapies is provided, including an overview of conventional and new (including investigational) therapeutic approaches for the treatment of hemophilia. The SIPPET study, the first randomized clinical trial to demonstrate a lower incidence of inhibitors in previously untreated patients treated with plasma-derived FVIII products compared with recombinant FVIII products, has generated much debate. We review the SIPPET trial and reactions, in addition to preliminary observations from a single center's experience, the cost impact of inhibitors, recent findings from SIPPET subanalyses, and inhibitor development in previously-treated patients. Expert commentary: Despite recent advances in potential new treatment options for hemophilia, conventional factor replacement concentrates currently remain the cornerstone of treatment. It is paramount that clinicians familiarize themselves with the findings from the SIPPET trial and substudies, in order to better inform their patients and families on inhibitor risk factors and to aid the treatment decision-making process.

Inhibitor development in haemophilia according to concentrate

Inhibitor development represents the most serious side effect of haemophilia treatment. Any difference in risk of inhibitor formation depending on the product used might be of clinical relevance. It was this study’s objective to assess inhibitor development according to clotting factor concentrate in severe haemophilia A and B. The European Haemophilia Safety Surveillance (EUHASS) was set up as a study monitoring adverse events overall and according to concentrate. Since October 2008, inhibitors were reported at least quarterly. Number of treated patients was reported annually, specifying the number of patients completing 50 exposure days (Previously Untreated Patients, PUPs) without inhibitor development. Cumulative incidence, incidence rates and 95 % confidence intervals (CI) were calculated. Data from October 1, 2008 to December 31, 2012 were analysed for 68 centres that validated their data. Inhibitors developed in 108/417 (26 %; CI 22–30 %) PUPs with severe haemophilia A and 5/72 (7 %; CI 2–16%) PUPs with severe haemophilia B. For Previously Treated Patients (PTPs), 26 inhibitors developed in 17,667 treatment years [0.15/100 treatment years; CI 0.10–0.22) for severe haemophilia A and 1/2836 (0.04/100; (CI 0.00–0.20) for severe haemophilia B. Differences between plasma-derived and recombinant concentrates, or among the different recombinant FVIII concentrates were investigated. In conclusion, while confirming the expected rates of inhibitors in PUPs and PTPs, no class or brand related differences were observed.

Management of Hemophilia in Older Patients

In recent decades, several improvements in hemophilia care have resulted in increased quality of life and life expectancy for those affected by this inherited hemorrhagic condition. Nowadays, individuals with hemophilia enjoy a life expectancy at birth close to that of males in the general population. As a consequence of the increasing age of the hemophilia population, a growing number of these patients develop age-related co-morbidities, such as cardiovascular disease and cancer, the management of which represents a new challenge for caregivers at hemophilia treatment centers. This narrative review focuses on the clinical problems arising in older people with hemophilia, with particular attention to the optimal therapeutic strategies.

Efficacy, Reliability, and Safety of Completely Autologous Fibrin Glue in Neurosurgical Procedures: Single-Center Retrospective Large-Number Case Study

OBJECTIVE

Commercially available fibrin glue (Com-FG), which is used commonly worldwide, is produced with pooled human plasma from multiple donors. However, it has added bovine aprotinin, which involves the risk of infection, allogenic immunity, and allergic reactions. We evaluate the efficacy, reliability, and safety of completely autologous fibrin glue (CAFG).

METHODS

From August 2014 to February 2016, prospective data were collected and analyzed from 153 patients. CAFG was prepared with the CryoSeal System using autologous blood and was applied during neurosurgical procedures. Using CAFG-soaked oxidized regenerated cellulose and/or polyglycolic acid sheets, we performed a pinpoint hemostasis, transposed the offending vessels in a microvascular decompression, and covered the dural incision to prevent cerebrospinal fluid leakage.

RESULTS

The CryoSeal System had generated up to a mean of 4.51 mL (range, 3.0-8.4 mL) of CAFG from 400 mL autologous blood. Com-FG products were not used in our procedures. Only 6 patients required an additional allogeneic blood transfusion. The hemostatic effective rate was 96.1% (147 of 153 patients). Only 1 patient who received transsphenoidal surgery for a pituitary adenoma presented with the complication of delayed postoperative cerebrospinal fluid leakage (0.65%). No patient developed allergic reactions or systemic complications associated with the use of CAFG.

CONCLUSIONS

CAFG effectively provides hemostatic, adhesive, and safety performance. The timing and three-dimensional shape of CAFG-soaked oxidized regenerated cellulose and/or polyglycolic acid sheets solidification can be controlled with slow fibrin formation. The cost to prepare CAFG is similar compared with Com-FG products, and it can therefore be easily used at most institutions.

Progress in the contemporary management of hemophilia: The new issue of patient aging

The management of inherited coagulation disorders such as hemophilia A and B has witnessed dramatic progresses since the last few decades of the last century. Accordingly, persons with hemophilia (PWH) now enjoy a life expectancy at birth not different from that of males in the general population, at least in high income countries. Nowadays, a substantial proportion of PWH are aging, like their peers in the general population. This outstanding progress is accompanied by problems that are in part similar to those of any old person (multiple concomitant diseases and the resulting intake of multiple drugs other than those specific for hemophilia treatment). In addition, older PWH suffer from the consequences of the comorbidities that developed when their treatment was at the same time poorly available and unsafe. Typical hemophilia comorbidities affect the musculoskeletal system following joint and muscle bleeds, but also the liver and kidney are often impaired due to previous bloodborne infections such as viral hepatitis and HIV. Thus, the comorbidities of hemophilia superimposed on the multimorbidity and polypharmacy associated with aging create peculiar problems in the current management of these patients, that demand the coordinated holistic intervention of internists, geriatricians and clinical pharmacologists in addition to the care traditionally provided by pediatricians and hematologists.

The History of Clotting Factor Concentrates Pharmacokinetics

Clotting factor concentrates (CFCs) underwent tremendous modifications during the last forty years. Plasma-derived concentrates made the replacement therapy feasible not only in the hospital but also at patients’ home by on-demand or prophylactic regimen. Virucidal methods, implemented soon after hepatitis and AIDS outbreak, and purification by Mabs made the plasma-derived concentrates safer and purer. CFCs were considered equivalent to the other drugs and general rules and methods of pharmacokinetics (PK) were applied to their study. After the first attempts by graphical methods and calculation of In Vivo Recovery, compartment and non-compartment methods were applied also to the study of PK of CFCs. The bioequivalence of the new concentrates produced by means of recombinant DNA biotechnology was evaluated in head-to-head PK studies. Since the beginning, the large inter-patient variability of dose/response of replacement therapy was realized. PK allowed tailoring haemophilia therapy and PK driven prophylaxis resulted more cost effective. Unfortunately, the need of several blood samples and logistic difficulties made the PK studies very demanding. Recently, population PK (PopPK) has been applied to the prediction of CFCs dosing by Bayesian methodology. By PopPK also sparse data may allow evaluating the appropriateness of replacement therapy.

Production of recombinant coagulation factors: Are humans the best host cells?

The main treatment option for Hemophilia A/B patients involves the administration of recombinant coagulation factors on-demand or in a prophylactic approach. Despite the safety and efficacy of this replacement therapy, the development of antibodies against the coagulation factor infused, which neutralize the procoagulant activity, is a severe complication. The production of recombinant coagulation factors in human cell lines is an efficient approach to avoid such complication. Human cell lines can produce recombinant proteins with post translation modifications more similar to their natural counterpart, reducing potential immunogenic reactions. This review provides a brief overview of the most important characteristics of recombinant FVIII and FIX products available on the market and the improvements that have recently been achieved by the production using human cell lines.

The past and future of haemophilia: diagnosis, treatments, and its complications

Haemophilia A and B are hereditary haemorrhagic disorders characterised by deficiency or dysfunction of coagulation protein factors VIII and IX, respectively. Recurrent joint and muscle bleeds lead to severe and progressive musculoskeletal damage. Existing treatment relies on replacement therapy with clotting factors, either at the time of bleeding (ie, on demand) or as part of a prophylactic schedule. The major complication of such therapy is the development of neutralising antibodies (ie, inhibitors), which is most frequent in haemophilia A. Treatment might improve considerably with the availability of new modified drugs, which might overcome existing prophylaxis limitations by reducing dosing frequency and thereby rendering therapy less distressing for the patient. Subcutaneous administration of some new therapies would also simplify prophylaxis in children with poor venous access. Gene therapy has the potential for a definitive cure, and important results have been obtained in haemophilia B. Despite improvements in haemophilia care, the availability of clotting factor concentrates for all affected individuals worldwide remains the biggest challenge.

Reliability of Microwave Heating for Hemoderivative Thawing

The spoiling of coagulation factors, proteic patterns and specific activity has been comparatively determined in fresh frozen plasma, cryoprecipitates and hemodiagnostic sera, thawed in a 37 degrees C water bath and in a microwave oven. Effects of conventional and microwave heating are not significantly different, while results of the latter technique are rapid and aseptic. Previously, heating performances of a commercial microwave oven have been investigated for deionized water, saline solutions, and bovine serum. Furthermore, plastic containers of hemoderivatives have been tested to assure that no toxic products are released during microwave heating.

Where now for transfusion: the evolution of a paradigm and its logical progression

The development of transfusion over the past century and a half has been described as one of the blessings of modern medicine. But, in some ways, it is emerging as a decidedly mixed blessing, bringing epidemics as well as improved health. Given all the practice has been through, now is the right time to take a critical look at blood transfusion as it is practiced today, and whether it serves the individual patient as effectively as the interests of those who administer it.

Some Important Milestones in the Field of Blood Clotting

Several different kinds of 'milestone' in the field of blood coagulation are described from the middle decades of the 20th century. Although viewed from the standpoint of clotting per se, attention is also given to implications for innate immunity. The first milestone considered is the protracted saga of clotting dependence on vitamin K, an adventure that spanned more than five decades beginning in the 1920s. The second has to do with the discovery of a half-dozen 'new' clotting factors during the period immediately following World War II. A third pursues a narrower focus and examines the once mysterious transformation of fibrinogen into fibrin. Finally, the clinical treatment of classical hemophilia had a remarkable turning point in the 1960s as the result of simple but sensible measures.

The long and short of it: using the new factor products

Hemophilia A (HA) and B (HB) are classified as mild (>5%-40%) moderate (1%-5%) and severe (<1%) disease based on plasma factor activity. Severity of bleeding is commensurate with baseline factor levels in general; however, heterogeneity of bleeding in patients is well described. Recurrent bleeding with painful and disabling musculoskeletal complications is the largest source of morbidity for persons with hemophilia (PWH) but treatment advances through the years has led to improved outcomes. In the early 20th century, only whole blood and fresh frozen plasma (FFP) was available to treat bleeding episodes. In 1959, cryoprecipitate was discovered and became an option for treatment of HA in 1965. In the 1970s plasma fractionation led to the first standard half-life (SHL) concentrates. These products ushered in the use prophylactic therapy to prevent bleeding episodes. However, viral contamination slowed the use of prophylaxis until the 1980s when viral attenuation steps increased the safety of plasma concentrates. In the 1990s recombinant concentrates were developed and prophylactic therapy is increasing widely yet not yet universally used. However even with frequent SHL concentrate infusions outcomes are not optimal as PWH spend the majority of time with factor levels below the normal range and are at increased risk for bleeding. In 2014, the first extended half-life (EHL) products were approved for use and have begun to change the landscape of hemophilia care. Challenges of EHL implementation include patient selection, product selection, dose and schedule of infusions, monitoring for safety, efficacy and outcomes, and managing economic aspects of care.

Gene therapy for hemophilia: past, present and future

After numerous preclinical studies demonstrated consistent success in large and small animal models, gene therapy has finally seen initial signs of clinically meaningful success. In a landmark study, Nathwani and colleagues reported sustained factor (F)IX expression in individuals with severe hemophilia B following adeno-associated virus (AAV)-mediated in vivo FIX gene transfer. As the next possible treatment-changing paradigm in hemophilia care, gene therapy may provide patients with sufficient hemostatic improvement to achieve the World Federation of Hemophilia's aspirational goal of "integration of opportunities in all aspects of life… equivalent to someone without a bleeding disorder." Although promising momentum supports the potential of gene therapy to replace protein-based therapeutics for hemophilia, several obstacles remain. The largest challenges appear to be overcoming the cellular immune responses to the AAV capsid; preexisting AAV neutralizing antibodies, which immediately exclude approximately 50% of the target population; and the ability to scale-up vector manufacturing for widespread applicability. Additional obstacles specific to hemophilia A (HA) include designing a vector cassette to accommodate a larger cDNA; avoiding development of inhibitory antibodies; and, perhaps the greatest difficulty to overcome, ensuring adequate expression efficiency. This review discusses the relevance of gene therapy to the hemophilia disease state, previous research progress, the current landscape of clinical trials, and considerations for promoting the future availability of gene therapy for hemophilia.

A brief review of 50 years of perioperative thrombosis and hemostasis management

Perioperative thrombosis and hemostasis management has changed dramatically over the past 50 years. From two anticoagulants and one anti-aggregant, the number of currently available drugs has recently increased several-fold, leaving clinicians with the problem of choosing the optimal agent. Individualized preoperative assessment of bleeding risk based on bleeding history and testing limited to high-risk patients is an emerging concept. Based on the identification of risk factors for venous thromboembolism (VTE), pharmacologic and non-pharmacologic strategies for perioperative VTE prophylaxis have had a major impact on patient outcome. For patients undergoing surgery who are treated with anticoagulants and anti-aggregants, "bridging" strategies have been proposed. Bleeding management strategies have shifted focus from replacing lost blood volume to new approaches aimed at preventing blood loss, reducing the potential complications of blood loss, and preventing the transfusion of blood products. For some areas of perioperative thrombosis and hemostasis management, randomized controlled trial (RCT) data are emerging, but the database remains insufficient to date. Clearly, more RCTs need to be published for perioperative thrombosis and hemostasis management to become an evidence-based approach.

Native analysis of plasma-derived clotting factor VIII concentrates: "sponge effect" and contaminants

In the present study, we analysed two commercially available plasma-derived FVIII preparations, Beriate and Emoclot, through native gel-based approaches (CN-PAGE). The rationale behind this study was to assess whether protein complexes from plasma resisted the aggressive manufacturing processes. A preliminary analysis of plasma complexes was performed focusing on the molecular weight range between 45 kDa and 1 MDa. As a result, we could evidence in both preparations the presence of complexes, which resisted the cryoprecipitation, chromatographic and heat treatment processing steps. These complexes behaved in a "sponge-effect"-like fashion through the enrichment of otherwise less abundant contaminants. The use of an alternative electrophoretic approach such as CN-PAGE allowed us to confirm 2DE-based observations and expand the list of non-FVIII proteins which contaminate the preparations.