Concentrated von Willebrand factor for treating patients with von Willebrand disease

For patients with von Willebrand disease, functional levels of circulating von Willebrand factor (VWF) need to be raised to establish hemostasis or prevent excessive or delayed bleeding as immediately prior to and then after invasive procedures. For the common, mild deficiencies, an initial response to DDAVP (desmopressin) is usually sufficient for hemostasis; additional or follow-up dosing may be required, however. For those patients in whom an adequate hemostatic response cannot be achieved with DDAVP, on in whom DDAVP is contraindicated, treatment or supplementation with a plasma-derived concentrate containing VWF is necessary. The functional content of VWF in concentrates varies, however, and optimal dosing in terms of activity and frequency remain to be defined. For perspective, previous clinical usage of cryoprecipitate is compared to recent series with different concentrates. The latter include use to provide hemostasis for acute bleeding episodes or to prevent excessive bleeding from invasive procedures including surgeries.