Von Willebrand Disease

The aim of this study is to assess the pharmacokinetics (PK), efficacy, and safety of Biostate® in subjects with Von Willebrand Disease (VWD). Pharmacokinetic Component: PK parameters will be determined from a subgroup of subjects. Subjects who complete the PK component will subsequently continue in the efficacy component of the study, either continuing on a previously established prophylaxis regimen or continuing to receive on-demand treatment with the occurrence of non-surgical bleeding (NSB) events. Efficacy Component: Three treatment arms are defined for the efficacy component of the study. (1) Subjects who are currently being treated on a set prophylaxis regimen with a VWF product at the time of study entry will be enrolled in the "Prophylaxis" arm. (2) Subjects not being treated on a set prophylaxis regimen at the time of study entry who require a VWF product for the treatment of NSB events will be enrolled in the "On-demand" arm and commence using Biostate in the treatment o