Abstract Number: PB0919
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » VWF and von Willebrand Factor Disorders - Clinical Conditions
Background: Type 3 von Willebrand disease (type 3 VWD) is the rarest and most severe form of VWD, with almost total or near total lack of VWF. This also leads to a deficiency of factor VIII, which can no longer be protected by VWF. Current treatment for patients with type 3 VWD consists of on-demand infusions of plasma derived FVIII/VWF combinations or recombinant VWF factor. Prophylaxis is not standard of care. The FDA has approved emicizumab-kxwh, a subcutaneously administered, humanized, bispecific, monoclonal antibody to FIXa and FX that substitutes FVIIIa function, for prophylaxis in patients with hemophilia A of all ages. Since type 3 VWD also has low FVIII, we report the successful, novel, prophylactic use of emicizumab-kxwh in four individuals with type 3 VWD including 2 children and 2 adults.
Aims: Reports of significant improvement in symptoms in patients with type 3 VWD after institution of emicizimab-kxwh prophylaxis.
Methods: Case reports of two adult female patients with type 3 VWD who suffered from a lifetime of complications associated with severe hemorrhagic events requiring multiple hospitalizations, infusions of factor concentrate, and blood transfusions. Started prophylaxis with emicizumab-kxwh in the spring/summer of 2019.
Two pediatric patients aged 2 and 6 years, hospitalized multiple times for significant bleeding after minor childhood traumas. They had been treated with multiple doses of factor VIII/VWF concentrates and even recombinant FVIIa. Initiated prophylaxis with emicizumab-kxwh.
Results: Significant improvement in the symptoms of all patients and the adults’ perception of quality of life.
Conclusions: Subcutaneous emicizumab-kxwh prophylaxis in symptomatic patients with type 3 VWD was effective. As more substituting and rebalancing therapies in hemostasis become available, guidelines for prophylaxis in bleeding disorders like type 3 VWD will change. Multicenter trials about efficacy and safety as well as patient-reported outcomes (PRO) will greatly help in formulating the guidelines.
To cite this abstract in AMA style:
Pawar A, Braunstein K, Michals J, Vo K, Schafer K. Prophylactic Subcutaneous Emicizumab-kxwh in Adults and Children with Symptomatic Type 3 von Willebrand Disease [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/prophylactic-subcutaneous-emicizumab-kxwh-in-adults-and-children-with-symptomatic-type-3-von-willebrand-disease/. Accessed April 25, 2024.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/prophylactic-subcutaneous-emicizumab-kxwh-in-adults-and-children-with-symptomatic-type-3-von-willebrand-disease/