BIVV001, a new class of factor VIII replacement for hemophilia A that is independent of von Willebrand factor in primates and mice

Abstract Factor VIII (FVIII) replacement products enable comprehensive care in hemophilia A. Treatment goals in severe hemophilia A are expanding beyond low annualized bleed rates to include long-term outcomes associated with high sustained FVIII levels. Endogenous von Willebrand factor (VWF) stabilizes and protects FVIII from degradation and clearance, but it also subjects FVIII to a half-life ceiling of ∼15 to 19 hours. Increasing recombinant FVIII (rFVIII) half-life further is ultimately dependent upon uncoupling rFVIII from endogenous VWF. We have developed a new class of FVIII replacement, rFVIIIFc-VWF-XTEN (BIVV001), that is physically decoupled from endogenous VWF and has enhanced pharmacokinetic properties compared with all previous FVIII products. BIVV001 was bioengineered as a unique fusion protein consisting of a VWF-DʹD3 domain fused to rFVIII via immunoglobulin-G1 Fc domains and 2 XTEN polypeptides (Amunix Pharmaceuticals, Inc, Mountain View, CA). Plasma FVIII half-life after BIVV001 administration in mice and monkeys was 25 to 31 hours and 33 to 34 hours, respectively, representing a three- to fourfold increase in FVIII half-life. Our results showed that multifaceted protein engineering, far beyond a few amino acid substitutions, could significantly improve rFVIII pharmacokinetic properties while maintaining hemostatic function. BIVV001 is the first rFVIII with the potential to significantly change the treatment paradigm for severe hemophilia A by providing optimal protection against all bleed types, with less frequent doses. The protein engineering methods described herein can also be applied to other complex proteins.

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Successful Treatment with Emicizumab of Patient with Type 2N Normandy and Severe Hemophilia a

Blood ◽

10.1182/blood-2021-153096 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 4249-4249

Author(s):

Paulette Bryant ◽

Elizabeth Lineberger ◽

Courtney Huckel Carr ◽

Angela Kaus

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Half Life ◽

Elbow Joint ◽

Hemophilia A ◽

Bleeding Episode ◽

Treatment Burden ◽

Severe Hemophilia ◽

Von Willebrand ◽

Willebrand Factor

Abstract It is unusual to have both Type 2N VWD and severe hemophilia A. Type 2N (Normandy) von Willebrand Disease (VWD) is an uncommon recessive disorder resulting in a defect in the binding site of von Willebrand Factor (VWF) with factor VIII. Factor VIII plasma levels are low due to rapid clearance. Our patient has severe hemophilia A (factor VIII <1%; Inversion 22) with no history of inhibitors and is heterozygous for a known pathogenic mutation (c2560C>T; p. Arg854Trp) Type 2N "Normandy". He benefited from the use of HEMLIBRA® (Emicizumab-kxwh, Genentech) a humanized bispecific monoclonal antibody with a long half-life independent of VWF interaction. The patient was diagnosed at 11 months old with excessive bleeding from his frenulum and began episodic standard factor VIII. He had 10 bleeds including knees, arms and hamstring before starting prophylaxis at 3 yrs. of age. On ADVATE 50 units/kg/dose twice a week he had nose bleeds, soft tissue bleeds, and joint bleeds. At 11 yrs. of age, the nose bleeds increased daily. VWD testing revealed VWF activity 25%, VWF Antigen 42%, Factor VIII <1% and Normal Multimers with Type 2 Normandy genotype. ALPHANATE® (Anti-hemophiliac factor/von Willebrand factor complex (human), Grifols) prophylaxis was started to address mucosal bleeding however the right elbow synovitis progressed to right elbow contracture and bone cyst on MRI. He returned briefly to ADVATE® 50 units/kg MWF to every other day prophylaxis with continued intermittent bleeding in right elbow joint. With the diagnosis of Type 2N, and the availability of VONVENDI ® (Recombinant von Willebrand factor, Takeda), he was placed on ADYNOVATE® (Antihemophilic Factor Recombinant PEGylated, Takeda) daily and VONVENDI® every 3rd day starting at 14 yrs. old. The combination of ADYNOVATE® every 12-24 hours with VONVENDI® daily to every other day improved his acute bleeding episodes including his nose bleeds (Half-life ADONYVATE®+VONVENDI® 9.25 hr. vs. Half-life ADVATE® 5.5 hr.). The patient continued to participate in high-risk activities such as playing on trampoline which contributed to his injuries but his family felt the treatment was better than previous therapies. After considering the treatment burden of 2 types of factors more than 5 times a week and progression of synovitis in right elbow joint, the patient was started on HEMLIBRA® with weekly subcutaneous injections. Four weeks of loading dose (3 mg/kg/dose) was followed by once per week prophylaxis at standard dosing 1.5 mg/kg weekly. The first bleeding episode on HEMLIBRA® was reported after tooth restoration October 2019. After receiving both ADYNOVATE® and VONVENDI® pre-op, he developed swelling with suspected hematoma at the angle of his jaw about 4 days post-op treated successfully with ADYNOVATE® /VONVENDI®. In April 2020, he had right elbow pain stereotypic of a joint bleeding episode after yard work which was treated successfully with ADYNOVATE® /VONVENDI®. No report of severe nosebleeds. To our knowledge this is the first example of successful use of HEMLIBRA® in a patient with Type 2N VWD and severe hemophilia A. It is unclear why the ALPHANATE® was not clinically effective however the combination of VONVENDI® and ADYNOVATE® provided improved hemostasis with frequent infusions and high cost before the start of HEMLIBRA®. HEMLIBRA once a week has significantly reduced the treatment burden and improved bleeding prevention. The genotype of this patient is unusual however this approach may be successful in other types of VWD that result in significant bleeding phenotype. Figure 1 Figure 1. Disclosures Bryant: Novo Nordisk: Consultancy, Honoraria; Bristol Myers Squib: Consultancy, Honoraria; Hema Biologics: Consultancy, Honoraria. Carr: Genentech: Speakers Bureau; Bayer: Speakers Bureau; Medexus: Speakers Bureau.

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Normal cleavage of von Willebrand factor by ADAMTS-13 in the absence of factor VIII in patients with severe hemophilia A

Journal of Thrombosis and Haemostasis ◽

10.1111/jth.12299 ◽

2013 ◽

Vol 11 (9) ◽

pp. 1769-1772 ◽

Cited By ~ 3

Author(s):

J. Chen ◽

D. W. Chung ◽

J. Le ◽

M. Ling ◽

B. A. Konkle ◽

...

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Hemophilia A ◽

Severe Hemophilia ◽

Von Willebrand ◽

Willebrand Factor

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Normal Cleavage of Von Willebrand Factor by ADAMTS13 In the Absence of Factor VIII In Patients with Severe Hemophilia A

Blood ◽

10.1182/blood.v116.21.2114.2114 ◽

2010 ◽

Vol 116 (21) ◽

pp. 2114-2114

Author(s):

Junmei Chen ◽

Dominic W. Chung ◽

Jennie Le ◽

Barbara A. Konkle ◽

José A. López

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Hemophilia A ◽

Conflicts Of Interest ◽

Ex Vivo ◽

Adamts13 Activity ◽

Severe Hemophilia ◽

Post Infusion ◽

Von Willebrand ◽

Willebrand Factor

Abstract Abstract 2114 The size of von Willebrand factor (VWF), a carrier protein for factor VIII (FVIII), is regulated by plasma metalloprotease ADAMTS13 proteolytic activity. Recently studies by Cao et al. (PNAS, 2008; 105: 7416–7421) found that under shear stress, exogenous FVIII enhanced ADAMTS13 cleavage of VWF, especially the high molecular weight multimers, in a system using purified proteins. Based on this result, the authors suggested that in the absence of FVIII, such as in patients with severe hemophilia A, VWF will have ultra-large multimers due to defects in ADAMTS13 proteolytic process, which can be corrected by infusion of FVIII. Here, we assessed VWF multimers, antigen, and ADAMTS13 activity in citrated plasma from seven patients with severe hemophilia A. The FVIII levels in six patients were less than 1% and in one was 4%. Plasma from two patients was available both pre- and post-FVIII replacement therapy (recombinant FVIII). All patients displayed VWF multimer patterns similar to those in pooled normal plasma (PNP), and the two patients receiving FVIII infusions displayed no change in VWF multimer size or pattern between their pre- and post-infusion samples. In all patients, the VWF antigen level (0.32–0.76) was below the PNP value (designated as 1), and all had increased ADAMTS13 activity (measured by the ability of plasma to cleave a small A2 peptide substrate) (1.09–1.79, PNP designated as 1), yielding an increased ratio of ADAMTS13 activity to VWF antigen in these patients (1.4–5.2 compared to PNP). We also examined cleavage of endogenous VWF by ADAMTS13 in the plasmas of the two patients studied pre- and post-infusion, yielding different FVIII levels. In this assay, we first diluted plasma 10-fold with a buffer containing 10 mM HEPES, 6.5 mM BaCl2, and 1.5 M urea, incubated at 37°C, and ADAMTS13 cleavage was stopped at different time points with EDTA. VWF multimer patterns were examined on a 1.5% agarose gel. We found that ADAMTS13 cleaved VWF efficiently in patient plasma deficient in FVIII, similar to that in PNP. The extent of cleavage was correlated with the ratio of ADAMTS13 activity to VWF antigen, rather than with the FVIII levels. In conclusion, patients with severe hemophilia A appear to have normal ADAMTS13 processing of VWF multimers in vivo and ex vivo. Further studies of the effect of FVIII and VWF levels on ADAMTS13 cleavage of VWF and clinical correlation are needed. Disclosures: No relevant conflicts of interest to declare.

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Cost analysis of plasma-derived factor VIII/von Willebrand factor versus recombinant factor VIII for treatment of previously untreated patients with severe hemophilia A in the United States

Journal of Medical Economics ◽

10.1080/13696998.2018.1468335 ◽

2018 ◽

Vol 21 (8) ◽

pp. 762-769 ◽

Cited By ~ 5

Author(s):

Ellis J. Neufeld ◽

Robert F. Sidonio ◽

Ken O’Day ◽

M. Chris Runken ◽

Kellie Meyer ◽

...

Keyword(s):

United States ◽

Cost Analysis ◽

Factor Viii ◽

Von Willebrand Factor ◽

Hemophilia A ◽

Factor Versus ◽

The United States ◽

Severe Hemophilia ◽

Von Willebrand ◽

Willebrand Factor

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Role of factor VIII-binding capacity of endogenous von Willebrand factor in the development of factor VIII inhibitors in patients with severe hemophilia A

Haematologica ◽

10.3324/haematol.2018.212001 ◽

2019 ◽

Vol 104 (8) ◽

pp. e369-e372 ◽

Cited By ~ 3

Author(s):

Yohann Repessé ◽

Catherine Costa ◽

Roberta Palla ◽

Elika Farrokhi Moshai ◽

Annie Borel-Derlon ◽

...

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Hemophilia A ◽

Binding Capacity ◽

Severe Hemophilia ◽

Von Willebrand ◽

Willebrand Factor

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Faculty Opinions recommendation of Alloantibodies to therapeutic factor VIII in hemophilia A: the role of von Willebrand factor in regulating factor VIII immunogenicity.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725335385.793503724 ◽

2015 ◽

Author(s):

Gili Kenet

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Hemophilia A ◽

Von Willebrand ◽

Willebrand Factor

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A novel cause of mild/moderate hemophilia A: mutations scattered in the factor VIII C1 domain reduce factor VIII binding to von Willebrand factor

Blood ◽

10.1182/blood.v96.3.958 ◽

2000 ◽

Vol 96 (3) ◽

pp. 958-965 ◽

Cited By ~ 55

Author(s):

Marc Jacquemin ◽

Renaud Lavend'homme ◽

Abdellah Benhida ◽

Beatrijs Vanzieleghem ◽

Roseline d'Oiron ◽

...

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

Cho Cells ◽

Hemophilia A ◽

Chinese Hamster ◽

Expression Vectors ◽

Scatchard Analysis ◽

C1 Domain ◽

Von Willebrand ◽

Willebrand Factor

Abstract The mechanisms responsible for the low factor VIII (fVIII) activity in the plasma of patients with mild/moderate hemophilia A are poorly understood. In such patients, we have identified a series of fVIII mutations (Ile2098Ser, Ser2119Tyr, Asn2129Ser, Arg2150His, and Pro2153Gln) clustered in the C1 domain and associated with reduced binding of fVIII to von Willebrand factor (vWf). For each patient plasma, the specific activity of mutated fVIII was close to that of normal fVIII. Scatchard analysis showed that the affinity for vWf of recombinant Ile2098Ser, Ser2119Tyr, and Arg2150His fVIII mutants was reduced 8-fold, 80-fold, and 3-fold, respectively, when compared with normal fVIII. Given the importance of vWf for the stability of fVIII in plasma, these findings suggested that the reduction of fVIII binding to vWf resulting from the above-mentioned mutations could contribute to patients' low fVIII plasma levels. We, therefore, analyzed the effect of vWf on fVIII production by Chinese hamster ovary (CHO) cells transfected with expression vectors for recombinant B domain-deleted normal, Ile2098Ser, Ser2119Tyr, and Arg2150His fVIII. These 3 mutations impaired the vWf-dependent accumulation of functional fVIII in culture medium. Analysis of fVIII production by transiently transfected CHO cells indicated that, in addition to the impaired stabilization by vWf, the secretion of functional Ile2098Ser and Arg2150His fVIII was reduced about 2-fold and 6-fold, respectively, by comparison to Ser2119Tyr and normal fVIII. These findings indicate that C1-domain mutations resulting in reduced fVIII binding to vWf are an important cause of mild/moderate hemophilia A.

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Genetic determinants of VWF clearance and FVIII binding modify FVIII pharmacokinetics in pediatric hemophilia A patients

Blood ◽

10.1182/blood.2019000190 ◽

2019 ◽

Vol 134 (11) ◽

pp. 880-891 ◽

Cited By ~ 7

Author(s):

Laura L. Swystun ◽

Kenichi Ogiwara ◽

Orla Rawley ◽

Christine Brown ◽

Ilinca Georgescu ◽

...

Keyword(s):

Blood Group ◽

Von Willebrand Factor ◽

Half Life ◽

Hemophilia A ◽

Blood Type ◽

Abo Blood Group ◽

Genetic Determinants ◽

Group Status ◽

Von Willebrand ◽

Willebrand Factor

Abstract Factor VIII (FVIII) pharmacokinetic (PK) properties show high interpatient variability in hemophilia A patients. Although previous studies have determined that age, body mass index, von Willebrand factor antigen (VWF:Ag) levels, and ABO blood group status can influence FVIII PK, they do not account for all observed variability. In this study, we aim to describe the genetic determinants that modify the FVIII PK profile in a population of 43 pediatric hemophilia A patients. We observed that VWF:Ag and VWF propeptide (VWFpp)/VWF:Ag, but not VWFpp, were associated with FVIII half-life. VWFpp/VWF:Ag negatively correlated with FVIII half-life in patients with non-O blood type, but no correlation was observed for type O patients, suggesting that von Willebrand factor (VWF) half-life, as modified by the ABO blood group, is a strong regulator of FVIII PK. The FVIII-binding activity of VWF positively correlated with FVIII half-life, and the rare or low-frequency nonsynonymous VWF variants p.(Arg826Lys) and p.(Arg852Glu) were identified in patients with reduced VWF:FVIIIB but not VWF:Ag. Common variants at the VWF, CLEC4M, and STAB2 loci, which have been previously associated with plasma levels of VWF and FVIII, were associated with the FVIII PK profile. Together, these studies characterize the mechanistic basis by which VWF clearance and ABO glycosylation modify FVIII PK in a pediatric population. Moreover, this study is the first to identify non-VWF and non-ABO variants that modify FVIII PK in pediatric hemophilia A patients.

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