Phase 3 study of recombinant von Willebrand factor in patients with severe von Willebrand disease who are undergoing elective surgery

Abstract The safety, efficacy, and optimal dosing of a von Willebrand Factor/Factor VIII concentrate (Humate-P®) were evaluated in an open-label, uncontrolled study in patients with von Willebrand disease (VWD) undergoing elective surgery. During an initial pharmacokinetic (PK) phase, a detailed profile of FVIII:C, VWF:RCo, and VWF:AG was obtained for each patient after an infusion of 60 IU VWF:RCo/kg as Humate-P. Individual PK values were used to calculate subsequent loading and maintenance doses. Hemostatic efficacy was characterized using a 4-point scale (excellent, good, moderate/poor, or none) at several time points following surgery. Forty-two adults and children were enrolled in the study (17 VWD type 1; 6 type 2; 13 type 3; 6 type 2M), and 35 of these patients underwent a surgical procedure (classified as 3 oral, 7 minor, and 25 major). The median loading dose administered was 55.6 IU/kg (range 17.4 to 135.3 IU/kg). For patients with more severe VWD (baseline VWF:RCo<12 IU/dL), the median loading dose administered was 70.9 IU/kg (range 38.6 to 135.3 IU/kg). The dosing interval was 8 or 12 hours in most subjects (4 were dosed every 6 hours), and treatment duration ranged from 1 to 6 days depending on surgery type. Effective hemostasis (investigator- rated as “excellent” or “good”) was noted in 91.4% (32/35) of subjects immediately after surgery, 100% (35/35) of subjects 14 days after surgery, and 100% (34/34) of subjects evaluated 24 hours after the last infusion (primary endpoint). Mean blood loss was less than expected, and four patients required transfusions, related to their surgery. Only six adverse events were considered possibly treatment related: headache (3), itching, nausea, and dizziness (1). These results demonstrate that von Willebrand Factor/Factor VIII concentrate is safe and effective in the prevention of excessive bleeding during and after elective surgery in adult and pediatric patients with von Willebrand disease.

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von Willebrand factor/factor VIII concentrate (Humate-P) for management of elective surgery in adults and children with von Willebrand disease

Haemophilia ◽

10.1111/j.1365-2516.2011.02534.x ◽

2011 ◽

Vol 17 (6) ◽

pp. 895-905 ◽

Cited By ~ 36

Author(s):

J. C. GILL ◽

A. SHAPIRO ◽

L. A. VALENTINO ◽

J. BERNSTEIN ◽

C. FRIEDMAN ◽

...

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Elective Surgery ◽

Von Willebrand Disease ◽

Adults And Children ◽

Von Willebrand ◽

Willebrand Factor

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Hemostatic efficacy, safety, and pharmacokinetics of a recombinant von Willebrand factor in severe von Willebrand disease

Blood ◽

10.1182/blood-2015-02-629873 ◽

2015 ◽

Vol 126 (17) ◽

pp. 2038-2046 ◽

Cited By ~ 71

Author(s):

Joan C. Gill ◽

Giancarlo Castaman ◽

Jerzy Windyga ◽

Peter Kouides ◽

Margaret Ragni ◽

...

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Treatment Success ◽

Von Willebrand Disease ◽

Phase 3 ◽

Host Cell Proteins ◽

Terminal Half Life ◽

Hemostatic Efficacy ◽

Von Willebrand ◽

Willebrand Factor

Abstract This phase 3 trial evaluated the safety and hemostatic efficacy of a recombinant von Willebrand factor (rVWF) for treatment of bleeds in severe von Willebrand disease (VWD). rVWF was initially administered together with recombinant factor VIII (rFVIII) and subsequently alone, as long as hemostatic factor VIII activity (FVIII:C) levels were maintained. Pharmacokinetics (PK) were evaluated in a randomized cross-over design (rVWF vs rVWF:rFVIII at 50 IU VWF:ristocetin cofactor activity [RCo]/kg). Bleed control for all treated bleeds (N = 192 bleeds in 22 subjects) was rated good or excellent (96.9% excellent; 119 of 122 minor, 59 of 61 moderate, and 6 of 7 major bleeds) on a 4-point scale (4 = none to 1 = excellent). A single infusion was effective in 81.8% of bleeds. Treatment success, defined as the number of subjects with a mean efficacy rating of <2.5, was 100%. The PK profile of rVWF was not influenced by rFVIII (mean VWF:RCo terminal half-life: 22.6 hours for rVWF and 22.5 hours for rVWF:rFVIII). FVIII:C levels increased rapidly after rVWF alone, with hemostatic levels achieved within 6 hours and sustained through 72 hours after infusion. Eight adverse effects (AEs; 6 nonserious AEs in 4 subjects and 2 serious AEs [chest discomfort and increased heart rate, without cardiac symptomatology] concurrently in 1 subject) were associated with rVWF. There were no thrombotic events or severe allergic reactions. No VWF or FVIII inhibitors, anti-VWF binding antibodies, or antibodies against host cell proteins were detected. These results show that rVWF was safe and effective in treating bleeds in VWD patients and stabilizes endogenous FVIII:C, which may eliminate the need for rFVIII after the first infusion. This trial was registered at www.clinicaltrials.gov as #NCT01410227.

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How I treat low von Willebrand factor levels

Blood ◽

10.1182/blood-2018-10-844936 ◽

2019 ◽

Vol 133 (8) ◽

pp. 795-804 ◽

Cited By ~ 14

Author(s):

Michelle Lavin ◽

James S. O’Donnell

Keyword(s):

Von Willebrand Factor ◽

Elective Surgery ◽

Von Willebrand Disease ◽

International Consensus ◽

Sequence Variations ◽

Clinical Case Studies ◽

International Consensus Guidelines ◽

Von Willebrand ◽

Willebrand Factor

Abstract Partial quantitative deficiency of plasma von Willebrand factor (VWF) is responsible for the majority of cases of von Willebrand disease (VWD), the most common inherited human bleeding disorder. International consensus guidelines recommend that patients with reduced plasma VWF antigen (VWF:Ag) levels and bleeding phenotypes be considered in 2 distinct subsets. First, patients with marked reductions in plasma VWF levels (<30 IU/dL) usually have significant bleeding phenotypes and should be classified with “type 1 VWD.” In contrast, patients with intermediate reduced plasma VWF levels (in the range of 30-50 IU/dL) should be considered in a separate category labeled “low VWF levels.” These patients with low VWF commonly display variable bleeding phenotypes and often do not have VWF gene sequence variations. Because the pathophysiology underlying low VWF levels remains largely undefined, diagnosis and management of these patients continue to pose significant difficulties. In this article, we present a number of clinical case studies to highlight these common clinical challenges. In addition, we detail our approach to establishing a diagnosis in low VWF patients and discuss strategies for the management of these patients in the context of elective surgery and pregnancy.

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The Interaction of Botrocetin with Normal or Variant von Willebrand Factor (Types IIA and IIB) and Its Inhibition by Monoclonal Antibodies that Block Receptor Binding

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646298 ◽

1992 ◽

Vol 68 (04) ◽

pp. 464-469 ◽

Cited By ~ 9

Author(s):

Y Fujimura ◽

S Miyata ◽

S Nishida ◽

S Miura ◽

M Kaneda ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Von Willebrand Factor ◽

Binding Activity ◽

Von Willebrand Disease ◽

Platelet Glycoprotein ◽

Normal Individuals ◽

Rag 1 ◽

The One ◽

Von Willebrand ◽

Willebrand Factor

SummaryWe have recently shown the existence of two distinct forms of botrocetin (one-chain and two-chain), and demonstrated that the two-chain species is approximately 30 times more active than the one-chain in promoting von Willebrand factor (vWF) binding to platelet glycoprotein (GP) Ib. The N-terminal sequence of two-chain botrocetin is highly homologous to sea-urchin Echinoidin and other Ca2+-dependent lectins (Fujimura et al., Biochemistry 1991; 30: 1957–64).Present data indicate that purified two-chain botrocetin binds to vWF from plasmas of patients with type IIA or IIB von Willebrand disease and its interaction is indistinguishable from that with vWF from normal individuals. However, an “activated complex” formed between botrocetin and IIB vWF expresses an enhanced biological activity for binding to GP Ib whereas the complex with IIA vWF has a decreased binding activity. Among several anti-vWF monoclonal antibodies (MoAbs) which inhibit ristocetin-induced platelet aggregation and/or vWF binding to GPIb, only two MoAbs (NMC-4 and RFF-VIII RAG:1) abolished direct binding between purified botrocetin and vWF. This suggests that they recognize an epitope(s) on the vWF molecule in close proximity to the botrocetin binding site.

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The Genetic Defect of Type I von Willebrand Disease “Vicenza” Is Linked to the von Willebrand Factor Gene

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651575 ◽

1993 ◽

Vol 69 (02) ◽

pp. 173-176 ◽

Cited By ~ 5

Author(s):

Anna M Randi ◽

Elisabetta Sacchi ◽

Gian Carlo Castaman ◽

Francesco Rodeghiero ◽

Pier Mannuccio Mannucci

Keyword(s):

Von Willebrand Factor ◽

Autosomal Dominant ◽

Genetic Defect ◽

Von Willebrand Disease ◽

Type I ◽

Bleeding Tendency ◽

Factor Gene ◽

Low Levels ◽

Von Willebrand ◽

Willebrand Factor

SummaryType I von Willebrand disease (vWD) Vicenza is a rare variant with autosomal dominant transmission, characterized by the presence of supranormal von Willebrand factor (vWF) multimers in plasma, similar to those normally found in endothelial cells and megakaryocytes. The patients have very low levels of plasma vWF contrasting with a mild bleeding tendency. The pathophysiology of this subtype is still unknown. The presence of supranormal multimers in the patients’ plasma could be due to a mutation in the vWF molecule which affects post-translational processing, or to a defect in the cells’ processing machinery, independent of the vWF molecule. In order to determne if type I vWD Vicenza is linked to the vWF gene, we studied six polymorphic systems identified within the vWF gene in two apparently unrelated families with type I vWD Vicenza. The results of this study indicate a linkage between vWF gene and the type I vWD Vicenza trait. This strongly suggests that type I vWD Vicenza is due to a mutation in one of the vWF alleles, which results in an abnormal vWF molecule that is processed to a lesser extent than normal vWF.

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Characterization of Partial Gene Deletions in Type III von Willebrand Disease with Alloantibody Inhibitors

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648835 ◽

1994 ◽

Vol 72 (02) ◽

pp. 180-185 ◽

Cited By ~ 22

Author(s):

David J Mancuso ◽

Elodee A Tuley ◽

Ricardo Castillo ◽

Norma de Bosch ◽

Pler M Mannucci ◽

...

Keyword(s):

Von Willebrand Factor ◽

Von Willebrand Disease ◽

Pcr Analysis ◽

Gene Deletions ◽

Factor Gene ◽

Type Iii ◽

Large Deletions ◽

Von Willebrand ◽

Willebrand Factor

Summaryvon Willebrand factor gene deletions were characterized in four patients with severe type III von Willebrand disease and alloantibodies to von Willebrand factor. A PCR-based strategy was used to characterize the boundaries of the deletions. Identical 30 kb von Willebrand factor gene deletions which include exons 33 through 38 were identified in two siblings of one family by this method. A small 5 base pair insertion (CCTGG) was sequenced at the deletion breakpoint. PCR analysis was used to detect the deletion in three generations of the family, including two family members who are heterozygous for the deletion. In a second family, two type III vWD patients, who are distant cousins, share an -56 kb deletion of exons 22 through 43. The identification and characterization of large vWF gene deletions in these type III vWD patients provides further support for the association between large deletions in both von Willebrand factor alleles and the development of inhibitory alloantibodies.

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Autoantibody Selectively Inhibits Binding of von Willebrand Factor to Glycoprotein Ib. Recognition Site Is Located in the A1 Loop of von Willebrand Factor

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656047 ◽

1997 ◽

Vol 77 (04) ◽

pp. 760-766 ◽

Cited By ~ 4

Author(s):

Hiroshi Mohri ◽

Etsuko Yamazaki ◽

Zekou Suzuki ◽

Toshikuni Takano ◽

Shumpei Yokota ◽

...

Keyword(s):

Von Willebrand Factor ◽

Significant Inhibition ◽

Von Willebrand Disease ◽

Recognition Site ◽

Severe Bleeding ◽

Bleeding Tendency ◽

Virtual Absence ◽

Heavy Chains ◽

Von Willebrand ◽

Willebrand Factor

SummaryA 20-year-old man with severe von Willebrand disease recently presented a progressive bleeding tendency, characterized recurrent subcutaneous hemorrhages and cerebral hemorrhage. Mixing and infusion studies suggested the presence of an inhibitor directed against vWF:RCo activity of von Willebrand factor (vWF) without significant inhibition of the FVIII:C. The inhibitor was identified as an antibody of IgG class. The inhibitor inhibited the interaction of vWF in the presence of ristocetin and that of asialo-vWF with GPIb while it partially blocked botrocetin-mediated interaction of vWF to GPIb. The inhibitor reacted with native vWF, the 39/34kDa fragment (amino acids [aa] 480/ 481-718) and the recombinant vWF fragment (MalE-rvWF508-704), but not with Fragment III-T2 (heavy chains, aa 273-511; light chains, aa 674-728). A synthetic peptide (aa 514-542) did not inhibit vWF-inhibitor complex formation. We conclude that this is the first autoantibody of class IgG from human origin that recognizes the sequence in the A1 loop of vWF, resulting in a virtual absence of functional vWF and a concomitant severe bleeding tendency although recognition site is different from the residues 514-542 which is crucial for vWF-GPIb interaction.

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