ATHN 9: Severe VWD Natural History Study

ATHN 9 is a natural history study to assess the safety of various Von Willebrand Factor (VWF) regimens for different indications (on-demand, surgery and prophylaxis) in adult and pediatric participants with clinically severe congenital VWD.

Inclusion Criteria: 1. Participants with severe Von Willebrand Disease with Type 3 VWD or VWF:RCo, VWF:GPlbM or VWF:Ag ≤30% of pooled normal control plasma on more than one occasion; 2. Participants with clinically severe VWD as defined by VWF:RCo, VWF:GPlbM or VWF:Ag ≤40% of normal with severe bleeding phenotype defined as requiring recurrent use of factor concentrates; and 3. Co-enrollment in the ATHNdataset. Exclusion Criteria: 1. Diagnosis of platelet-type VWD; 2. Diagnosis of acquired VWD (clinical diagnosis based on association with hypothyroidism, lymphoproliferative and myeloproliferative disorders, malignancies and cardiovascular disease, typically aortic stenosis or LVAD).