The Phase 3 WIL-31 study was the largest prospective study with an on-demand run in study as an intra-individual comparator investigating the efficacy and safety of VWF prophylaxis in patients with VWD and provides evidence for the use of wilate prophylaxis to reduce HMB in girls/women with VWD. Here, VWF is linked to von Willebrand disease (hereditary or acquired).