Treatment and prevention of acute bleedings in von Willebrand disease--efficacy and safety of Wilate, a new generation von Willebrand factor/factor VIII concentrate

Hemostatic management of von Willebrand disease during childbirth with a plasma-derived von Willebrand factor/factor VIII concentrate

BACKGROUND

Females with von Willebrand disease (VWD) do not show the same increases in von Willebrand factor and factor (F)VIII levels during pregnancy as females without VWD and are at higher risk of excessive bleeding associated with childbirth. Data on hemostatic management for childbirth in VWD patients are limited.

OBJECTIVES

To evaluate the dosing, efficacy, and safety of plasma-derived von Willebrand factor/FVIII (wilate) for prevention of excessive bleeding associated with childbirth in females with any type of VWD.

METHODS

Data for females with VWD who received wilate for hemostatic coverage for childbirth during 2 prospective clinical studies were analyzed.

RESULTS

Ten females with VWD and a mean age at enrolment of 29.6 years were treated with wilate to prevent excessive bleeding associated with childbirth. Two patients had type 1, 4 had type 2 (2 2A, 1 2B, and 1 2M), and 4 had type 3 VWD. Of the 10 deliveries, 5 were by cesarean section. Patients received a mean of 9.5 infusions of wilate over 6.8 exposure days, with a mean total dose of 234 IU/kg per delivery and 25 IU/kg per infusion. Hemostatic management for all deliveries was rated excellent or good, with no excessive bleeding during delivery and no postpartum bleeding during the period of wilate treatment in any patient. Two patients experienced 8 possible or probable treatment-related adverse events; all were mild or moderate and resolved. No thromboembolic events were observed.

CONCLUSION

The results of this case series indicate that wilate provided effective hemostatic cover for childbirth in females with VWD during delivery and postpartum.

Improved prevention of bleeding episodes with emicizumab in 3 patients with concomitant hemophilia A and von Willebrand disease

The typical phenotype of hemophilia A (HA) is that of frequent bleeding episodes, up to several per month, unless prophylactic factor VIII (FVIII) replacement or alternatives are given. Related bleeding may be heightened in severity or frequency by co-morbid bleeding disorders. Based on the reported prevalence of von Willebrand disease (VWD) of up to 1% of the general population, the co-existence of HA and VWD occurs, but is likely less recognized. Prophylactic FVIII replacement may or may not adequately prevent bleeding in persons with HA and mild VWD, and plasma-derived concentrates containing FVIII and von Willebrand factor (VWF) may be used for more successful bleeding prophylaxis. However, therapy adherence remains problematic for many reasons, one being treatment via intravenous access. Emicizumab is a nonfactor subcutaneous prophylactic therapy for HA that may overcome this concern. We describe three patients, with severe HA and VWD, for whom regular FVIII/VWF prophylaxis was deemed inadequate. FVIII/VWF prophylaxis was replaced with weekly prophylactic injections of the bispecific monoclonal antibody, emicizumab. When the patients were transitioned to emicizumab, all experienced a significant reduction in their annualized bleed rate (ABR). Although the mechanism of action does not directly affect or replace VWF function, emicizumab may be an effective prophylaxis alternative to FVIII/VWF concentrate in patients with concomitant severe HA and VWD.

von Willebrand disease

von Willebrand disease (VWD) is the most common inherited bleeding disorder. The disorder is characterized by excessive mucocutaneous bleeding. The most common bleeding manifestations of this condition include nosebleeds, bruising, bleeding from minor wounds, menorrhagia or postpartum bleeding in women as well as bleeding after surgery. Other less frequent symptoms include gastrointestinal bleeding, haematomas or haemarthroses. VWD pathophysiology is complex and results from defects in von Willebrand factor (VWF) glycoprotein. Quantitative deficiencies are responsible for type 1 VWD with a partial decrease of VWF and type 3 with the complete absence of VWF. Qualitative abnormalities cause type 2 VWD, being further divided into types 2A, 2B, 2M and 2N. Although common, VWD is at risk of misdiagnosis, overdiagnosis and underdiagnosis owing to several factors, including complex diagnosis, variability of bleeding symptoms, presence of external variables (blood groups and other physiological modifiers such as exercise, thyroid hormones, oestrogens, and ageing), and lack of disease awareness among non-specialist health-care providers. Establishing the correct VWD diagnosis requires an array of specialized phenotypic assays and/or molecular genetic testing of the VWF gene. The management of bleeding includes increasing endogenous VWF levels with desmopressin or infusion of exogenous VWF concentrates (plasma-derived or recombinant). Fibrinolytic inhibitors, topical haemostatic agents and hormonal therapies are used as effective adjunctive measures.

Retrospective chart review of GI bleeding in people with von Willebrand disease

INTRODUCTION

Gastrointestinal (GI) bleeding events (BEs) in von Willebrand disease (VWD) are difficult to diagnose and often recurrent. Limited data from clinical trials has led to lack of consensus on treatment options.

AIM

Describe current treatments and outcomes for GI BEs in people with VWD.

METHODS

This retrospective, observational, multicentre chart review study was conducted from January 2018 through December 2019 and included patients with inherited VWD with ≥1 GI BE in the preceding 5 years. Baseline characteristics, number and aetiology of BEs, associated GI-specific morbidities/lesions, treatment and outcomes were analysed descriptively.

RESULTS

Sixty bleeds were reported in 20 patients with type 1 (20%), type 2 (50%) and type 3 (30%) VWD. During the 5-year study period, 31 (52%) BEs had one identified or suspected cause; multiple causes were reported in 11 (18%). Most GI BEs (72%) were treated with a combination of von Willebrand factor (VWF), antifibrinolytics and/or other haemostatic or non-haemostatic treatments. Time to resolution did not differ by VWF treatment use; however, BEs treated with non-VWF treatments tended to resolve later. In patients with GI-specific morbidities/lesions, 84% resolved with first-line treatment; time to resolution tended to be longer than in patients without such morbidities/lesions. Thirteen BEs occurred in patients receiving prophylaxis and 47 in patients receiving on-demand treatment; 18 BEs resulted in a switch to prophylaxis after bleed resolution.

CONCLUSIONS

This study confirms the unmet need for the management of recurrent GI BEs in people with VWD and the need for prospective data, especially on prophylaxis.

von Willebrand factor/factor VIII concentrate (Wilate) prophylaxis in children and adults with von Willebrand disease

ABSTRACT

Long-term prophylaxis with a von Willebrand factor (VWF) concentrate is recommended in patients with von Willebrand disease (VWD) who have a history of severe and frequent bleeds. However, data from prospective studies are scarce. WIL-31, a prospective, noncontrolled, international phase 3 trial, investigated the efficacy and safety of Wilate prophylaxis in severe patients with VWD. Male and female patients 6 years or older with VWD types 1, 2 (except 2N), or 3 who had completed a prospective, 6-month, on-demand, run-in study (WIL-29) were eligible to receive Wilate prophylaxis for 12 months. At baseline, patients (n = 33) had a median age of 18 years. Six (18%) patients had severe type 1, 5 (15%) had type 2, and 22 (67%) had type 3 VWD. The primary end point of a >50% reduction in mean total annualized bleeding rate (TABR) with Wilate prophylaxis vs prior on-demand treatment was met; mean TABR during prophylaxis was 5.2, representing an 84.4% reduction. The bleeding reduction was consistent across age, sex, and VWD types. The mean spontaneous ABR was 3.2, representing an 86.9% reduction vs on-demand treatment. During prophylaxis, 10 (30.3%) patients had 0 bleeding events and 15 (45.5%) patients had 0 spontaneous bleeding events. Of 173 BEs, 84.4% were minor and 69.9% treated. No serious adverse events related to study treatment and no thrombotic events were recorded. Overall, WIL-31 showed that Wilate prophylaxis was efficacious and well-tolerated in pediatric and adult patients with VWD of all types. The WIL-29 and WIL-31 trials were registered at www.ClinicalTrials.gov as #NCT04053699 and #NCT04052698, respectively.

Real-World Efficacy and Safety of Plasma-Derived Von Willebrand Factor-Containing Factor VIII Concentrates in Patients With Von Willebrand Disease in Italy

Plasma-derived von Willebrand factor-containing factor VIII concentrates (pd-VWF/FVIII-C) are the mainstay of treatment in von Willebrand disease (VWD). Real-world data on efficacy and safety of these pd-VWF/FVIII-C are required. To retrospectively evaluate the efficacy and safety of pd-VWF/FVIII-C (Fanhdi® and Alphanate®, Grifols) in clinical practice in Italy. A multicentric, observational, retrospective study at 10 Italian centers was conducted. Eligible patients diagnosed with inherited VWD (ISTH criteria) were treated with either Fanhdi® or Alphanate® for bleeding episodes, prevention of surgical bleeding and secondary long-term prophylaxis (SLTP) according to clinical practice with medical records collected from January 2007 to December 2019. Efficacy/safety of pd-VWF/FVIII-C was assessed according to FDA-agreed objective criteria following regulatory procedures. Fifty-seven patients (M/F: 21/36) were enrolled in the study with the following VWD types: VWD1 (n = 29, 52%), VWD2A (n = 10, 18%), VWD2B (n = 7, 12%), VWD2M (n = 2, 4%), VWD2N (n = 1, 2%), VWD2 unclassified (n = 1, 2%), and VWD3 (n = 7, 12%). These pd-VWF/FVIII-C were used to manage 58 bleeding episodes (n = 24 patients), 100 surgeries (n = 47 patients), and 7 SLTP (n = 6 patients). Global clinical efficacy with these pd-VWF/FVIII-C was reported to be excellent/good in 85% of bleeding episodes, 98% of surgeries, and 100% of SLTP. As far as safety, no adverse-drug-related episodes, immunogenic or thrombotic events were reported. This study confirmed that Fanhdi® and Alphanate® were effective and safe in the management of bleeding episodes, the prevention of bleeding during surgeries and for SLTP in Italian patients with inherited VWD.

Neurological Complications Associated with Hereditary Bleeding Disorders

PURPOSE OF REVIEW

Hereditary bleeding disorders may have a wide variety of clinical presentations ranging from mild mucosal and joint bleeding to severe central nervous system (CNS) bleeding, of which intracranial hemorrhage (ICH) is the most dreaded complication. In this review, we will discuss the pathophysiology of specific hereditary bleeding disorders, namely, hemophilia A, hemophilia B, and von Willebrand disease (vWD); their clinical manifestations with a particular emphasis on neurological complications; a brief overview of management strategies pertaining to neurological complications; and a review of literature guiding treatment strategies.

RECENT FINDINGS

ICH is the most significant cause of morbidity and mortality in patients with hemophilia. Adequate control of bleeding with the administration of specific factors or blood products, identification of risk factors for bleeding, and maintaining optimal coagulant activity are essential for appropriately managing CNS bleeding complications in these patients. The administration of specific recombinant factors is tailored to a patient's pharmacokinetics and steady-state levels. During acute bleeding episodes, initial factor activity should be maintained between 80 and 100%. Availability of monoclonal antibody Emicizumab has revolutionized prophylactic therapies in patients with hemophilia. Management of ICH in patients with vWD involves using plasma-derived factor concentrates, recombinant von Willebrand factor, and supportive antifibrinolytic agents individualized to the type and severity of vWD. Hemophilia and vWD are the most common hereditary bleeding disorders that can predispose patients to life-threatening CNS complications-intracranial bleeds, intraspinal bleeding, and peripheral nerve syndromes. Early care coordination with a hematologist can help develop an effective prophylactic regimen to avoid life-threatening bleeding complications in these patients. Further research is needed to evaluate using emicizumab as an on-demand treatment option for acute bleeding episodes in patients with hemophilia.

Targeting von Willebrand disease: the current status and future directions of management therapies

INTRODUCTION

von Willebrand disease (VWD) is the commonest inherited bleeding disorder, and is typically caused by deficits in the quantity or quality of von Willebrand factor (VWF).

AREAS COVERED

This review describes the main clinical, diagnostic, and therapeutic aspects of VWD, with particular attention to its management. In addition, standard and avant-garde replacement therapies based on the use of VWF are discussed.

EXPERT OPINION

The goal of treatment for VWD is to reverse the double hemostatic defect resulting from the abnormal or reduced expression of VWF and the concomitant factor VIII (FVIII) deficiency. Treatment consists of managing any bleeds and both short-term prophylaxis (i.e. for surgery or invasive procedures) and long-term prophylaxis. While desmopressin is suitable for most patients with type 1 VWD, VWF/FVIII concentrates are the treatment of choice for the other types of VWD. Beside plasma-derived VWF/FVIII concentrates, whose safety and efficacy have been demonstrated by several clinical trials, products containing only VWF, obtained by plasma fractionation and recombinant DNA technology, have become available and marketed more recently. The clinical use of these VWF-only products is particularly attractive in the setting of surgery and long-term prophylaxis, such as the prevention of recurrent gastrointestinal bleeding in cases of angiodysplasia.

Gastrointestinal bleeding in von Willebrand patients: special diagnostic and management considerations

INTRODUCTION

Severe and recurrent gastrointestinal (GI) bleeding caused by angiodysplasia is a significant problem in patients with von Willebrand disease (VWD) and in those with acquired von Willebrand syndrome (AVWS). At present, angiodysplasia-related GI bleeding is often refractory to standard treatment including replacement therapy with von Willebrand factor (VWF) concentrates and continues to remain a major challenge and cause of significant morbidity in patients despite advances in diagnostics and therapeutics.

AREAS COVERED

This paper reviews the available literature on GI bleeding in VWD patients, examines the molecular mechanisms implicated in angiodysplasia-related GI bleeding, and summarizes existing strategies in the management of bleeding GI angiodysplasia in patients with VWF abnormalities. Suggestions are made for further research directions.

EXPERT OPINION

Bleeding from angiodysplasia poses a significant challenge for individuals with abnormal VWF. Diagnosis remains a challenge and may require multiple radiologic and endoscopic investigations. Additionally, there is a need for enhanced understanding at a molecular level to identify effective therapies. Future studies of VWF replacement therapies using newer formulations as well as other adjunctive treatments to prevent and treat bleeding will hopefully improve care.

Patients with von Willebrand disease in China: Results of an online survey

INTRODUCTION

Little is known about the clinical characteristics of von Willebrand disease (VWD) patients in China, the impact of Covid-19 on them and their genetic mutation.

AIM

To describe the clinical characteristics of a group of VWD patients in China, the impact of Covid-19 on them and their genetic mutation.

METHODS

An online survey using a self-designed questionnaire was conducted among patients within a WeChat group of VWD patients in China. Data were analysed using t-test, the Chi-square test, Fisher's exact test and rank sum test.

RESULTS

Data from a total of 96 patients were collected. Several important findings are yielded. Above all, type 3 patients accounted for over half of the surveyed patients. Secondly, a surprising rate (>40%) of patients had experience of being misdiagnosed. Thirdly, treatment regimens were dominated by cryoprecipitate, blood-derived FVIII and plasma, and only a small percentage of patients received prophylaxis. Fourthly, we identified 17 new von Willebrand factor (VWF) mutant genes which merit further investigation. Additionally, Covid-19 was found to pose some challenges for the patients.

CONCLUSION

In China, the high rates of type 3 patients and misdiagnosis suggest that most of the VWD patients may never be diagnosed in China. When it comes to diagnosis and treatment, there is a large gap between developing countries like China and developed countries.

Special considerations in GI bleeding in VWD patients

Gastrointestinal (GI) bleeding is an important cause of morbidity and mortality in von Willebrand disease (VWD). It has been noted that GI bleeding caused by angiodysplasia is overrepresented in VWD patients compared to other causes. The bleeding from angiodysplasia is notoriously difficult to treat; recurrences and rebleeds are common. A growing body of basic science evidence demonstrates that von Willebrand factor negatively regulates angiogenesis through multiple pathways. VWD is clinically highly associated with angiodysplasia. The predisposition to angiodysplasia likely accounts for many of the clinical difficulties related to managing GI bleeding in VWD patients. Diagnosis and treatment are challenging with the current tools available, and much further research is needed to further optimize care for these patients with regard to acute treatment, prophylaxis, and adjunctive therapies. In this review we provide an overview of the available literature on GI bleeding in VWD and explore the molecular underpinnings of angiodysplasia-related GI bleeding. Considerations for diagnostic effectiveness are discussed, as well as the natural history and recurrence of these lesions and which therapeutic options are available for acute and prophylactic management.

Recombinant von Willebrand factor prophylaxis in patients with severe von Willebrand disease: phase 3 study results

International guidelines conditionally recommend long-term prophylaxis in patients with von Willebrand disease (VWD) and severe and frequent bleeding. As recombinant von Willebrand factor (rVWF; vonicog alfa) may reduce the frequency of treated spontaneous bleeding events (BEs), we investigated the efficacy and safety of rVWF prophylaxis in adults with severe VWD. Patients with BEs requiring VWF therapy in the past year (on-demand VWF therapy [prior on-demand group] or plasma-derived VWF prophylaxis [pdVWF; switch group]) were enrolled in a prospective, open-label, nonrandomized, phase 3 study. The planned duration of rVWF prophylaxis was 12 months; starting rVWF dose was 50 ± 10 VWF: ristocetin cofactor (VWF:RCo) IU/kg twice weekly (prior on-demand group) or based on prior pdVWF weekly dose/dosing frequency (switch group). The primary endpoint was annualized bleeding rate (ABR) of treated spontaneous BEs (sABR) during rVWF prophylaxis. Over the 12-month study period, treated sABR decreased by 91.5% on-study vs historical sABR in 13 patients in the prior on-demand group, and by 45.0% in 10 patients in the switch group (model-based analysis ratio, 0.085; 95% confidence interval [CI], 0.021-0.346 and 0.550; 95% CI, 0.086-3.523, respectively). No treated spontaneous BEs were recorded in 84.6% (11/13) and 70.0% (7/10) of patients, respectively. The safety profile of rVWF was consistent with the previously established profile, with no new adverse drug reactions identified. Findings suggest that rVWF prophylaxis can reduce treated spontaneous BEs in patients previously receiving on-demand VWF therapy and maintains at least the same level of hemostatic control in patients who switch from prophylaxis with pdVWF to rVWF, with a favorable safety profile. This trial was registered at www.clinicaltrials.gov (#NCT02973087) and www.clinicaltrialsregister.eu (#EudraCT 2016-001478-14).

Engineered Molecular Therapeutics Targeting Fibrin and the Coagulation System: a Biophysical Perspective

The coagulation cascade represents a sophisticated and highly choreographed series of molecular events taking place in the blood with important clinical implications. One key player in coagulation is fibrinogen, a highly abundant soluble blood protein that is processed by thrombin proteases at wound sites, triggering self-assembly of an insoluble protein hydrogel known as a fibrin clot. By forming the key protein component of blood clots, fibrin acts as a structural biomaterial with biophysical properties well suited to its role inhibiting fluid flow and maintaining hemostasis. Based on its clinical importance, fibrin is being investigated as a potentially valuable molecular target in the development of coagulation therapies. In this topical review, we summarize our current understanding of the coagulation cascade from a molecular, structural and biophysical perspective. We highlight single-molecule studies on proteins involved in blood coagulation and report on the current state of the art in directed evolution and molecular engineering of fibrin-targeted proteins and polymers for modulating coagulation. This biophysical overview will help acclimatize newcomers to the field and catalyze interdisciplinary work in biomolecular engineering toward the development of new therapies targeting fibrin and the coagulation system.

Outcomes of long-term von Willebrand factor prophylaxis use in von Willebrand disease: A systematic literature review

BACKGROUND

Von Willebrand Disease (VWD) is a common inherited bleeding disorder. Patients with VWD suffering from severe bleeding may benefit from the use of secondary long-term prophylaxis.

AIM

Systematically summarize the evidence on the clinical outcomes of secondary long-term prophylaxis in patients with VWD and severe recurrent bleedings.

METHODS

We searched Medline and EMBASE through October 2019 for relevant randomized clinical trials (RCTs) and comparative observational studies (OS) assessing the effects of secondary long-term prophylaxis in patients with VWD. We used Cochrane Risk of Bias (RoB) tool and the RoB for Non-Randomized Studies of interventions (ROBINS-I) tool to assess the quality of the included studies. We conducted random-effects meta-analyses and assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

We included 12 studies. Evidence from one placebo controlled RCT suggested that VWD prophylaxis as compared to no prophylaxis reduced the rate of bleeding episodes (Rate ratio [RR], .24; 95% confidence interval [CI], .17-.35; low certainty evidence), and of epistaxis (RR, .38; 95%CI, .21-.67; moderate certainty evidence), and may increase serious adverse events RR 2.73 (95%CI .12-59.57; low certainty). Evidence from four before-and-after studies in which researchers reported comparative data suggested that VWD prophylaxis reduced the rate of bleeding (RR .34; 95%CI, .25-.46; very low certainty evidence).

CONCLUSION

VWD prophylaxis treatment seems to reduce the risk of spontaneous bleeding, epistaxis, and hospitalizations. More RCTs should be conducted to increase the certainty in these benefits.

Clinical Efficacy and Safety of Fanhdi®, a Plasma-Derived VWF/Factor VIII Concentrate, in von Willebrand Disease in Spain: A Retrospective Study

Objective

To evaluate the efficacy and safety of a plasma-derived factor VIII concentrate containing von Willebrand Factor (pdVWF/FVIII) in standard clinical practice in von Willebrand Disease (VWD) patients.

Methods

A retrospective, multicentric, observational study of VWD patients treated with Fanhdi^®, a pdVWF/FVIII concentrate, from January 2011 to December 2017 was conducted at 14 centers in Spain. Efficacy and safety were evaluated for acute bleeding episodes, for prevention of bleeding in surgeries, and for secondary long-term prophylaxis.

Results

Seventy-two eligible patients, type 1, 2, 3 VWD (25%/38.9%/36.1%) were treated for spontaneous and traumatic bleeding (140 episodes, n = 41 patients), to prevent surgical bleeding (69 episodes, n = 43 patients); and for secondary long-term prophylaxis (18 programs, n = 13 patients). Replacement therapy with pdVWF/FVIII showed an excellent to good clinical efficacy in 96.7% of the bleeding episodes, 100% during surgical procedures and 100% during prophylaxis. No adverse events (AEs), nor serious AEs related to the product were observed.

Conclusions

Fanhdi^® was effective, safe and well tolerated in the management of bleeding episodes, the prevention of bleeding during surgeries, and for secondary long-term prophylaxis in VWD patients.

Gastrointestinal Bleeding in Congenital Bleeding Disorders

Gastrointestinal bleeding (GIB) is serious, intractable, and potentially life-threatening condition. There is considerable heterogeneity in GIB phenotypes among congenital bleeding disorders (CBDs), making GIB difficult to manage. Although GIB is rarely encountered in CBDs, its severity in some patients makes the need for a comprehensive and precise assessment of underlying factors and management approaches imperative. Initial evaluation of GIB begins with assessment of hematological status; GIB should be ruled out in patients with chronic anemia, and in presentations that include hematemesis, hematochezia, or melena. High-risk patients with recurrent GIB require urgent interventions such as replacement therapy for treatment of coagulation factor deficiency (CFD). However, the best management strategy for CFD-related bleeding remains controversial. While several investigations have identified CBDs as potential risk factors for GIB, research has focused on assessing the risks for individual factor deficiencies and other CBDs. This review highlights recent findings on the prevalence, management strategies, and alternative therapies of GIB related to CFDs, and platelet disorders.

Von Willebrand Disease: Current Status of Diagnosis and Management

Von Willebrand disease (VWD) is a common bleeding disorder, affecting male and female individuals equally, that often manifests in mucosal bleeding. VWD can be secondary to a quantitative (Type 1 and Type 3) or qualitative (Type 2) defects in Von Willebrand factor (VWF). Initial testing includes VWF antigen, as well as a platelet binding assay to differentiate between qualitative and quantitative defects. Further subtyping requires additional testing and is needed to ensure appropriate treatment. Desmopressin, antifibrinolytics, hormonal treatments for heavy menstrual bleeding, and VWF concentrates are commonly used in the treatment of VWD.

Real-World Data on the Effectiveness and Safety of wilate for the Treatment of von Willebrand Disease

Background  The efficacy and safety of wilate (human von Willebrand factor/coagulation factor VIII) in patients with von Willebrand disease (VWD) has been demonstrated in clinical trials. Here, we present real-world data on the use of wilate for the routine care of patients with VWD.

Objectives  The objectives of this observational, prospective, phase 4 study were to evaluate the safety, tolerability, and effectiveness of wilate in on-demand treatment of bleeding episodes (BEs), long-term prophylaxis, and surgical prophylaxis among patients with any type of VWD.

Methods  Patients were enrolled at 31 study centers in 11 countries and followed for up to 2 years. Safety endpoints included adverse drug reactions (ADRs) and drug tolerability. Effectiveness was assessed using annualized bleeding rates (ABRs) during prophylaxis and predefined criteria for the treatment of BEs and surgical prophylaxis.

Results  A total of 111 patients (76 [68%] female) including 41 (37%) children were treated with wilate. Twenty-five patients received prophylaxis, 29 on-demand treatment, and 62 surgical prophylaxis. Tolerability was rated by patients as “excellent” for 96.2% of 6,497 infusions. No unexpected ADRs or thrombotic events were reported. Median ABR during prophylaxis was 1.9. Effectiveness was assessed as “excellent” or “good” by patients and investigators for 100% of BEs treated on-demand, 98% (patient rating) and 99% (investigator rating) of breakthrough BEs, and 99% of surgical procedures (investigator rating).

Conclusion  wilate was safe, well tolerated, and effective for the prevention and treatment of bleeding in pediatric and adult VWD patients in a real-world setting.

ASH ISTH NHF WFH 2021 guidelines on the management of von Willebrand disease

BACKGROUND

von Willebrand disease (VWD) is a common inherited bleeding disorder. Significant variability exists in management options offered to patients.

OBJECTIVE

These evidence-based guidelines from the American Society of Hematology (ASH), the International Society on Thrombosis and Haemostasis (ISTH), the National Hemophilia Foundation (NHF), and the World Federation of Hemophilia (WFH) are intended to support patients, clinicians, and health care professionals in their decisions about management of VWD.

METHODS

ASH, ISTH, NHF, and WFH formed a multidisciplinary guideline panel. Three patient representatives were included. The panel was balanced to minimize potential bias from conflicts of interest. The University of Kansas Outcomes and Implementation Research Unit and the McMaster Grading of Recommendations Assessment, Development and Evaluation (GRADE) Centre supported the guideline development process, including performing and updating systematic evidence reviews (through November 2019). The panel prioritized clinical questions and outcomes according to their importance to clinicians and patients. The panel used the GRADE approach, including GRADE Evidence-to-Decision frameworks, to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 12 recommendations and outlined future research priorities.

CONCLUSIONS

These guidelines make key recommendations regarding prophylaxis for frequent recurrent bleeding, desmopressin trials to determine therapy, use of antiplatelet agents and anticoagulant therapy, target VWF and factor VIII activity levels for major surgery, strategies to reduce bleeding during minor surgery or invasive procedures, management options for heavy menstrual bleeding, management of VWD in the context of neuraxial anesthesia during labor and delivery, and management in the postpartum setting.

Translating the success of prophylaxis in haemophilia to von Willebrand disease

INTRODUCTION

There is limited awareness of von Willebrand disease (VWD), leading to challenges in both diagnosis and defining the optimal treatment approach for these patients. Patients with VWD are typically treated on-demand, with short-term prophylaxis used during surgery. In contrast, early initiation, and long-term use of prophylaxis is the standard of care in patients with severe haemophilia and can be successfully used to prevent joint bleeding and reduce chronic arthropathy.

AIM

To provide an understanding of the current evidence for the prophylactic treatment of patients with VWD and compare this to the management of patients with haemophilia.

METHODS

Review of published literature using a non-systematic search of PubMed and reference lists of sourced articles.

RESULTS

The successes seen with prophylaxis in haemophilia provide the rationale for long-term prophylaxis in patients with severe forms of VWD; preventing spontaneous, excessive and sometimes life-threatening bleeding, and reducing chronic joint disease. Currently, there are a few clinical trials assessing the long-term benefits of prophylaxis in VWD, and guidelines for the optimal prophylaxis treatment approach are lacking. Greater attempts to provide comprehensive, long-term care for patients with VWD are needed but still lacking within the community. This review highlights the success of prophylaxis in haemophilia and how this knowledge might be applied and translated to patients with VWD.

CONCLUSIONS

Lessons can be learned from the use of prophylaxis in haemophilia and prophylaxis should be considered the standard of care for a subgroup of patients with severe VWD.

An Open-Label Extension Study to Assess the Long-Term Efficacy and Safety of a Plasma-Derived von Willebrand Factor (VWF)/Factor VIII (FVIII) Concentrate in Patients with von Willebrand Disease (SWIFT-VWDext Study)

Objective

Plasma-derived von Willebrand factor/factor VIII (pdVWF/FVIII; VONCENTO^®, CSL Behring) is a high-concentration, low-volume, high-purity concentrate, which contains a high level of high-molecular-weight multimers and a VWF/FVIII ratio of ~2.4:1. The SWIFT ("Studies with von Willebrand factor/Factor VIII") program is evaluating pdVWF/FVIII in patients with von Willebrand disease (VWD). The long-term efficacy and safety profile of pdVWF/FVIII was investigated in this multicenter, open-label, extension study.

Methods

Pediatric, adolescent, and adult patients with VWD who required treatment of non-surgical bleeds (NSBs), treatment during surgical events or who were receiving prophylaxis and who had completed one of two previous clinical trials of pdVWF/FVIII were included. Efficacy and safety analyses were performed for on-demand (n=10), prophylaxis (n=8), or on-demand and prophylaxis (n=2) treatment in patients pre-treated with pdVWF/FVIII for ≥12 months.

Results

Seven patients experienced a total of 402 NSBs in the on-demand arm, of which 77 required treatment and nine NSB events in three patients were considered major. Nine patients reported 118 NSBs in the prophylaxis arm, with 96 events requiring treatment and seven patients experiencing 12 major NSB events. Excellent or good hemostatic efficacy was reported by the investigator for 98.7% (on-demand) and 97.9% (prophylaxis) of NSB events treated with pdVWF/FVIII, without relevant differences between subgroups by age. pdVWF/FVIII was well tolerated, and the adverse events seen were mild-moderate and consistent with the safety profile for this product seen in other studies. There were no cases of anaphylactic reactions and angioedema, development of VWF/FVIII inhibitors, thromboembolic events, or viral infections.

Conclusion

This contemporary comprehensive development program evaluating pdVWF/FVIII across all ages demonstrates long-term safety and efficacy for treatment and prevention of bleeds in patients with severe VWD, supporting the benefit-risk profile of pdVWF/FVIII.

New therapies for von Willebrand disease

The management of von Willebrand disease (VWD) is based upon the dual correction of the primary hemostasis defect, due to the inherited deficiency of von Willebrand factor (VWF), and of the secondary defect of factor VIII coagulant activity (FVIII:C), due to the loss of binding and stabilization by VWF of this intrinsic coagulation factor in flowing blood. The traditional therapeutic weapons (the synthetic derivative of the antidiuretic hormone desmopressin and plasma-derived VWF/FVIII concentrates) are able to transiently correct both the defects. With the goal of tackling the primary deficiency in the disease, that is, VWF, but at the same time exploiting the normal capacity of patients to produce FVIII, the novel approach of replacing only VWF was implemented in the last 10 years. Following the manufacturing of a concentrate fractionated from human plasma and of one obtained by recombinant DNA technology, clinical studies have shown that VWF-only products correct not only the primary VWF deficiency but also the secondary FVIII:C deficiency. The demonstrated efficacy of these products in various clinical situations and, ultimately, in such a hemostasis-challenging context as surgery testifies to the effectiveness and safety of this approach. It remains to be seen whether VWF-only products are efficacious and safe in still-unexplored situations, such as use in children; the long-term use for prophylaxis; and in recurrent gastrointestinal (GI) bleeding due to angiodysplasia, a major therapeutic problem in VWD.

Management of von Willebrand disease with a factor VIII-poor von Willebrand factor concentrate: Results from a prospective observational post-marketing study

BACKGROUND

A triple-secured plasma-derived von Willebrand factor (pdVWF) almost devoid of factor VIII (FVIII):WILFACTIN® , was approved in France in 2003, and then in other countries for the treatment of patients with von Willebrand disease (VWD).

OBJECTIVE

To investigate long-term safety and efficacy of the product in real-life over the first 5 post-approval years.

PATIENTS/METHODS

This prospective, observational, national post-marketing study (PMS) enrolled patients of all ages and VWD types. Patients were observed for up to 3 years and treated for one or more occasions. Efficacy was assessed for each major event. Breakthrough bleeding rate 3 days post-infusion and annualized bleeding rate (ABR) were also evaluated for long-term prophylaxis.

RESULTS

Overall, 155 of 174 patients enrolled from 31 centers were eligible for efficacy assessment. Most patients (76.8%) were severely affected (VWF:RCo ≤ 15 IU/dL). They were treated for 743 bleeds and 140 surgeries including childbirth. Efficacy outcomes were excellent/good for 98.2% of 56 major surgeries and 94.0% of 67 major bleeds. Approximately 75% of 49 major mucosal bleeds were effectively managed without FVIII co-administration. In 32 patients receiving prophylaxis, breakthrough bleeding occurred in 1.5% of infusions and median ABR was 1.0 for 20 patients treated ≥ 12 months. Excellent tolerability was confirmed with no safety concerns. No thrombotic events were observed.

CONCLUSIONS

Results from this PMS increase the clinical experience of a FVIII-poor pdVWF in patients of all ages and VWD types including those with thrombotic risk factors and emphasize that giving FVIII is not always mandatory to effectively treat patients with severe VWD.

Update and Review of Bleeding Considerations in Dermatologic Surgery: Anticoagulants and Antiplatelets

BACKGROUND

Bleeding is an unavoidable risk of dermatologic surgery. The risk may be higher in patients taking agents that affect hemostasis.

OBJECTIVE

The aim of this study was to provide an updated review of current anticoagulant and antiplatelet therapy available in the market and their associated risk of bleeding complications in cutaneous surgery.

MATERIALS AND METHODS

A review of PubMed and MEDLINE was performed to review the English-language medical literature.

RESULTS

Many anticoagulant and antiplatelet therapies exist. Several studies recommend the continued use of antiplatelet and anticoagulant medications in the perioperative period. Combination regimens and novel oral anticoagulants may be associated with an increased risk of bleeding.

CONCLUSION

An updated understanding of antiplatelet and anticoagulant agents is critical for the surgeon. Current evidence does not support the discontinuation of antiplatelet and anticoagulant agents in the perioperative period under most circumstances. However, relevant data on novel oral anticoagulant agents are still sparse, suggesting that a precautionary approach is warranted.

Pharmacokinetics, Efficacy and Safety of a Plasma-Derived VWF/FVIII Concentrate (Formulation V) in Pediatric Patients with von Willebrand Disease (SWIFTLY-VWD Study)

Purpose

Formulation V (VONCENTO^®) is a plasma-derived high-concentration/low-volume, high-purity von Willebrand factor (VWF)/factor VIII (FVIII) concentrate, originally indicated for von Willebrand disease (VWD) in adults and adolescents. This multicenter, open-label study (SWIFTLY-VWD) evaluated the pharmacokinetics (PK), as well as hemostatic efficacy and safety, of Formulation V in pediatric patients (<12 years) with severe VWD requiring treatment or prophylaxis of bleedings.

Methods

PK investigations were performed following one dose of Formulation V at Day 1 and 180. Nonsurgical bleeds were analyzed, while hemostatic efficacy was graded as excellent/good/moderate/none. Safety assessments included adverse events, and presence of VWF and/or FVIII inhibitors.

Results

Formulation V was administered as on-demand (N=13) or prophylaxis therapy (N=4) for 12 months (<6 years, N=9; 6 to <12 years, N=8). PK parameters for VWF markers were generally comparable to adults but showed lower VWF:ristocetin cofactor (RCo) exposure. Incidence of major bleeds was lower for prophylaxis (3.3%) than on-demand therapy (27.1%); joint bleeds were also lower (3.3% vs 11.5%, respectively). Investigator-reported excellent/good hemostatic efficacy against nonsurgical bleeds was 100%. No clinically relevant differences in PK, hemostatic efficacy, or safety were observed between age-groups (<6 years and 6 to <12 years). Formulation V was well tolerated. Adverse events were mild–moderate and consistent with the adult safety profile. No cases of anaphylactic reactions or angioedema, development of FVIII/VWF inhibitors, thromboembolic events, or viral infections were reported.

Conclusion

This study provides evidence for use of Formulation V to treat and prevent bleeding in pediatric patients with severe VWD, and led to the European approval of Formulation V in children.

New therapies for von Willebrand disease

The management of von Willebrand disease (VWD) is based upon the dual correction of the primary hemostasis defect, due to the inherited deficiency of von Willebrand factor (VWF), and of the secondary defect of factor VIII coagulant activity (FVIII:C), due to the loss of binding and stabilization by VWF of this intrinsic coagulation factor in flowing blood. The traditional therapeutic weapons (the synthetic derivative of the antidiuretic hormone desmopressin and plasma-derived VWF/FVIII concentrates) are able to transiently correct both the defects. With the goal of tackling the primary deficiency in the disease, that is, VWF, but at the same time exploiting the normal capacity of patients to produce FVIII, the novel approach of replacing only VWF was implemented in the last 10 years. Following the manufacturing of a concentrate fractionated from human plasma and of one obtained by recombinant DNA technology, clinical studies have shown that VWF-only products correct not only the primary VWF deficiency but also the secondary FVIII:C deficiency. The demonstrated efficacy of these products in various clinical situations and, ultimately, in such a hemostasis-challenging context as surgery testifies to the effectiveness and safety of this approach. It remains to be seen whether VWF-only products are efficacious and safe in still-unexplored situations, such as use in children; the long-term use for prophylaxis; and in recurrent gastrointestinal (GI) bleeding due to angiodysplasia, a major therapeutic problem in VWD.

A phase III study comparing secondary long-term prophylaxis versus on-demand treatment with vWF/FVIII concentrates in severe inherited von Willebrand disease

BACKGROUND

There is a lack of prospective clinical trials specifically designed to evaluate the benefits of prophylaxis with vWF/FVIII concentrates in patients with inherited von Willebrand disease (vWD). The aim of the study was to compare efficacy of secondary long-term prophylaxis (PRO) with vWF/FVIII in the prevention of bleeding episodes in severe vWD patients to standard of care (on-demand treatment; ODT).

MATERIALS AND METHODS

In this 12-month, phase III, open-label study (PRO.WILL), vWD patients (aged ≥6 years) were randomised to PRO (n=9; 5 completed) or ODT (n=10; 7 completed) treatment with Fanhdi^®/Alphanate^® (Grifols) according to current licensing status for use in vWD. We assessed the proportion of patients who did not present any spontaneous bleeding episode, adverse events (AEs) or thrombotic events.

RESULTS

All patients on ODT had vWD type 2 or 3 vs 70% of patients on PRO. All ODT patients experienced bleeds vs 60% on PRO. PRO patients showed fewer bleeds (n=32 vs n=172 [112 in the same patient, mostly mucosal]; p<0.0001) and lower risk of bleeding (relative attributable risk estimate: -0.667; 95% CI: -2.374, -0.107; p<0.001). Most frequent bleeds in ODT and PRO groups were, respectively, epistaxis (n=52 vs n=15) and gastrointestinal (n=13 [9 in the same patient] vs n=1). While most bleeds lasted one day under ODT (31/32), only epistaxis did so in PRO group (14/15). No AEs due to study medication were observed.

DISCUSSION

Despite the small sample size and the heterogeneity of the study population, patients on vWF/FVIII prophylaxis showed a reduction in bleeding risk and rate compared to on-demand treatment.

Efficacy and safety of a new generation von Willebrand factor/factor VIII concentrate (Wilate®) in the management of perioperative haemostasis in von Willebrand disease patients undergoing surgery

The aim of this study was to assess the efficacy of Wilate®, a new generation, plasma-derived, high-purity, double virus-inactivated von Willebrand factor (VWF) and factor VIII (FVIII) concentrate (ratio close to physiological 1:1) in the perioperative management of haemostasis in von Willebrand disease (VWD). Data for VWD patients who received Wilate® for perioperative management were obtained from four European, prospective, open-label, non-controlled, non-randomised, multicentre phase II or III clinical trials. A total of 57 surgical procedures were performed (major: n = 27; minor n = 30) in 32 patients. The majority of patients (n = 19, 59.4%) had type 3 VWD, 9 (28.1%) had type 2 VWD and four (12.5%) had type 1 VWD. During major surgery, median daily FVIII dose and mean number of infusions were 25 IU•kg-1 FVIII (VWF:RCô23 IU•kg-1) and 11.0, respectively. Corresponding values for minor surgery were 35 IU•kg-1 (VWF:RCo ~32 IU•kg-1) and 1.5. The efficacy of Wilate® was rated by the investigator as excellent or good in 51 of 53 (96%) procedures. Tolerability was rated as very good or good in 100% of major surgeries (27 of 27) and minor surgeries (29 of 29). Wilate® is an effective and well-tolerated VWF/FVIII replacement therapy in the perioperative management of haemostasis in patients with VWD. It can be administered at a similar FVIII dose, but at a lower VWF dose, as compared to older generation products. Clinical benefits were shown in a population with a high proportion of type 3 VWD patients.

Gastrointestinal angiodysplasia and bleeding in von Willebrand disease

Von Willebrand disease (VWD), the most common genetic bleeding disorder, is characterised by a quantitative or qualitative defect of von Willebrand factor (VWF). Patients with VWD suffer from mucocutaneous bleeding, of severity usually proportional to the degree of VWF defect. In particular, gastrointestinal bleeding associated with angiodysplasia is often a severe symptom of difficult management. This review focuses on the pathophysiology, diagnosis and treatment of VWD-associated gastrointestinal angiodysplasia and related bleeding.

Angiodysplasia in von Willebrand Disease: Understanding the Clinical and Basic Science

Severe and intractable gastrointestinal bleeding caused by angiodysplasia is a debilitating problem for up to 20% of patients with von Willebrand disease (VWD). Currently, the lack of an optimal treatment for this recurrent problem presents an ongoing challenge for many physicians in their management of affected patients. Over the past few years, studies have pointed to a regulatory role for the hemostatic protein, von Willebrand factor (VWF), in angiogenesis, providing a novel target for the modulation of vessel development. This article will review the clinical implications and molecular pathology of angiodysplasia in VWD.

Recombinant von Willebrand factor for severe gastrointestinal bleeding unresponsive to other treatments in a patient with type 2A von Willebrand disease: a case report

A recombinant von Willebrand factor (rVWF) was recently approved in the United States for on-demand treatment and control of bleeding episodes in adults with von Willebrand disease (VWD). In contrast to plasma-derived VWF products available in the United States, rVWF does not contain factor VIII (FVIII). To date, there is no published experience of rVWF in clinical practice. We report the acute and prophylactic use of rVWF in a patient with VWD type 2A and severe gastrointestinal bleeding. Dosing with plasma-derived VWF/FVIII concentrates was constrained by FVIII accumulation; the bleeding was unresponsive, and multiple red blood cell transfusions were required. After initiation of rVWF (4200 IU every other day), bleeding symptoms subsided, and no red blood cell transfusions were required during more than 3 months of prophylactic therapy (most recent dosage: 2800 IU every other day). rVWF may be effective in the prevention, as well as treatment, of severe bleeding symptoms in VWD.

Pharmacokinetics, efficacy, and safety of a plasma-derived VWF/FVIII concentrate (VONCENTO) for on-demand and prophylactic treatment in patients with von Willebrand disease (SWIFT-VWD study)

Supplemental Digital Content is available in the text

VONCENTO (CSL Behring Gmbh, Marburg, Germany) is a plasma-derived, high concentration, lower volume [relative to HAEMATE P (CSL Behring)], high-purity von Willebrand factor (VWF)/factor VIII (FVIII) concentrate with a VWF/FVIII ratio similar to HAEMATE P. This open-label, multicentre study investigated the pharmacokinetic, haemostatic efficacy, and safety profiles of VONCENTO in study participants at least 12 years of age with von Willebrand disease (VWD) who required treatment of nonsurgical bleeding (NSB) events or underwent surgery or prophylaxis. The first 12-month on-demand treatment period comprised a pharmacokinetic investigation and an efficacy analysis. After 12 months, qualifying study participants were switched to prophylactic therapy and included in a further 12-month efficacy analysis. In total, 21 study participants (including three adolescents, and 13 study participants with VWD type 3) received VONCENTO as on-demand treatment for 12 months. ‘Excellent’/‘good’ haemostatic efficacy was achieved in 98.3% of the 407 NSB events assessed by investigators. Following the switch to prophylactic treatment, the total number of NSBs in eight patients markedly decreased from 304 to 10 (with haemostatic efficacy judged to be ‘excellent’ for all). The annualised bleeding rate also significantly decreased from a median of 26.5 events to one event. Safety assessments showed no inhibitory antibodies to either FVIII or VWF, no transmission of infectious agents, no thromboembolic events and no treatment-related serious adverse events. VONCENTO was shown to be well tolerated and provided excellent haemostatic efficacy in the treatment of bleeds or during prophylaxis in study participants with VWD, including also those with type 3, the severest form of VWD.

Von Willebrand factor for menorrhagia: a survey and literature review

BACKGROUND

von Willebrand disease (VWD) is the most common congenital bleeding disorder. In women, menorrhagia is the most common bleeding symptom, and is disabling with iron deficiency anaemia, high health cost and poor quality of life. Current hormonal and non-hormonal therapies are limited by ineffectiveness and intolerance. Few data exist regarding von Willebrand factor (VWF), typically prescribed when other treatments fail. The lack of effective therapy for menorrhagia remains the greatest unmet healthcare need in women with VWD. Better therapies are needed to treat women with menorrhagia.

METHODS

We conducted a survey of US haemophilia treatment centres (HTCs) and a literature review using medical subject heading (MeSH) search terms 'von Willebrand factor,' 'menorrhagia' and 'von Willebrand disease' to assess the use of VWF in menorrhagia. Analysis was by descriptive statistics.

RESULTS

Of 83 surveys distributed to HTC MDs, 20 (24.1%) provided sufficient data for analysis. Of 1321 women with VWD seen during 2011-2014, 816 (61.8%) had menorrhagia, for which combined oral contraceptives, tranexamic acid and desmopressin were the most common first-line therapies for menorrhagia, whereas VWF was third-line therapy reported in 13 women (1.6%). Together with data from 88 women from six published studies, VWF safely reduced menorrhagia in 101 women at a dose of 33-100 IU kg(-1) on day 1-6 of menstrual cycle.

CONCLUSIONS

This represents the largest VWD menorrhagia treatment experience to date. VWF safely and effectively reduces menorrhagia in women with VWD. A prospective clinical trial is planned to confirm these findings.

Prophylaxis escalation in severe von Willebrand disease: a prospective study from the von Willebrand Disease Prophylaxis Network

BACKGROUND

Treatment of mucosal bleeding (epistaxis, gastrointestinal bleeding, and menorrhagia) and joint bleeding remains problematic in clinically severe von Willebrand disease (VWD). Patients are often unresponsive to treatment (e.g. desmopressin or antifibrinolytic therapy) and may require von Willebrand factor (VWF) replacement therapy. There are little data on the use of prophylaxis in VWD, and none have been applied in a prospective, treatment escalation design.

OBJECTIVE

Evaluate the effect of escalating dose prophylaxis in severe VWD.

METHODS

Patients eligible for enrollment in this prospective study included those with type 1 VWD with VW factor activity-ristocetin cofactor ratio ≤ 20% and unresponsive to desmopressin, patients with type 2 VWD not responsive to desmopressin and all subjects with type 2B and type 3 VWD. Entry criteria were strictly defined, as were therapy escalation parameters and clinical data collection.

RESULTS

Eleven subjects completed the study. Six had type 2A, and five had type 3 VWD. Six patients presented with epistaxis, three with GI bleeding, and two with joint bleeding. Seven had dose escalation above the first level. Among the 10 subjects with evaluable bleeding log data, use of prophylaxis decreased the median annualized bleeding rate from 25 to 6.1 (95% confidence interval of the rate difference: -51.6 to -1.7), and the median annualized bleeding rate was even lower (4.0; 95% confidence interval: -57.5 to -5.3) when the subjects reached their final dosing level.

CONCLUSION

This is the first prospective study to demonstrate that prophylaxis with VW factor concentrates is highly effective in reducing mucosal and joint bleeding rates in clinically severe VWD.

Successful aortic aneurysm repair in a woman with severe von Willebrand (type 3) disease

von Willebrand disease type 3 (VWD3) is a rare but the most severe form of von Willebrand disease; it is due to almost complete lack of von Willebrand factor activity (VWF:RCo). It is inherited as autosomal recessive trait; whilst heterozygote carriers have mild, or no symptoms, patients with VWD3 show severe bleeding symptoms. In the laboratory, this is characterised by undetectable VWF:Ag, VWF:RCo, and reduced levels of factor VIII < 0.02 IU/dL. The bleeding is managed with von Willebrand/FVIII factor concentrate replacement therapy. In this rare but challenging case we report on the successful excision and repair of an ascending aortic aneurysm following adequate VWF/FVIII factor concentrate replacement using Haemate-P.

Efficacy and safety of Wilate in paediatric VWD patients under 6 years of age - results of a prospective multicentre clinical study including recovery information

Treatment with exogenous von Willebrand factor (VWF) is indicated in patients with von Willebrand disease (VWD) in whom treatment with 1-deamino-8-d-arginine vasopressin/desmopressin is contraindicated. Wilate is a new generation plasma-derived concentrate of native VWF and coagulation factor VIII (FVIII) (in a physiological 1:1 ratio) developed for the treatment of VWD. This is the first study to report safety, efficacy and in vivo recovery (IVR) data from 15 paediatric patients less than 6 years of age who received Wilate for either prophylaxis, on-demand treatment or for treatment in surgical procedures during a prospective open-label trial (VWD type 1: 5, type 2A: 1, type 2B: 2, type 3: 6, unknown type: 1 patients). Analysis of IVR for VWF and FVIII suggested an appropriate and consistent rise in coagulation activity after Wilate administration. Overall efficacy was rated as excellent or good for 99.7% [prophylactic infusions] and 100% [bleeding episodes/surgical procedures]. More than 82% of bleeding episodes resolved after 1 day of treatment, and a Wilate dosage of 20-50 IU kg(-1) was sufficient to achieve haemostasis in 97% of bleeding episodes. All surgical procedures were successfully managed with Wilate. No thromboembolic events were observed during the study, and no patient developed anti-VWF antibodies or FVIII inhibitors. In conclusion, this study confirms both the expected IVR profile in paediatric patients and the excellent efficacy, tolerability and safety profile of Wilate observed previously in adults. Wilate showed excellent efficacy in the treatment of bleeding when used prophylactically or on-demand, and in the treatment of surgical procedures.

Von Willebrand disease-associated angiodysplasia: a few answers, still many questions

The association between angiodysplasia and von Willebrand disease (VWD) has been known for more than 40 years. Bleeding in the gastrointestinal tract associated with angiodysplasia worsens the clinical course of this inherited haemorrhagic disorder and management may become difficult and challenging. Angiodysplasia associated with acquired defects or dysfunctions of von Willebrand factor (VWF) has also been reported in a variety of conditions such as monoclonal gammopathies, Heyde syndrome and in carriers of ventricular assist devices. The most recent advances concerning the mechanistic, clinical and therapeutic aspects of VWD-associated angiodysplasia are summarized in this review, together with the limitations of our knowledge that warrant further research in the frame of international cooperation.

Von Willebrand disease

Long-term prophylaxis is not as well known in Von Willebrand disease (VWD) as in hemophilia but attempts to evaluate prophylaxis scientifically in VWD have started. A few cohort studies have been reported. In an international effort the Von Willebrand disease prophylaxis network (VWD PN) has been formed to investigate the role of prophylaxis in clinically severe VWD (e.g., patients with type 3 VWD) that is nonresponsive to other treatments. Findings from the VWD PN studies will hopefully provide more robust evidence for which patients might best benefit from prophylaxis and for appropriate dosing regimens for prophylaxis in patients with VWD.

von Willebrand's disease: a report from a meeting in the Åland islands

von Willebrand's disease (VWD) is probably the most common bleeding disorder, with some studies indicating that up to 1% of the population may have the condition. Over recent years interest in VWD has fallen compared to that of haemophilia, partly the result of focus on blood-borne diseases such as HIV and hepatitis. Now the time has come to revisit VWD, and in view of this some 60 international physicians with clinical and scientific interest in VWD met over 4 days in 2010 in the Åland islands to discuss state-of-the-art issues in the disease. The Åland islands are where Erik von Willebrand had first observed a bleeding disorder in a number of members of a family from Föglö, and 2010 was also the 140th anniversary of his birth. This report summarizes the main papers presented at the symposium; topics ranged from genetics and biochemistry through to classification of VWD, pharmacokinetics and laboratory assays used in the diagnosis of the disease, inhibitors, treatment guidelines in different age groups including the elderly who often have comorbid conditions that present challenges, and prophylaxis. Other topics included managing surgeries in patients with VWD and the role of FVIII in VWF replacement, a controversial subject.