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.

The purpose of this study is to create and maintain a registry, which is a database (a searchable collection of information) about children, adolescents and young adults with pediatric onset of rheumatic diseases. This data may help in the evaluation of the safety and benefit of medications that are prescribed to patients who have rheumatic diseases.