Efficacy and safety of a VWF/FVIII concentrate (wilate®) in inherited von Willebrand disease patients undergoing surgical procedures

Introduction: Surgical procedures in von Willebrand disease (VWD) patients may require prophylactic treatment with exogenous von Willebrand factor (VWF) and coagulation factor VIII (FVIII) to prevent excessive bleeding. Wilate® is a plasma-derived, double virus-inactivated, highly purified, freeze-dried VWF/FVIII concentrate, containing both factors in a physiological activity ratio of 1:1. Aim: To investigate the efficacy and safety of wilate® in maintaining haemostasis in VWD patients undergoing surgical procedures. Methods: This prospective, open-label multinational clinical study documents 28 individuals who underwent 30 surgical procedures managed with wilate®. Twenty-one patients had VWD Type 3, and 21 surgeries were major. Efficacy was assessed intra- and postoperatively by the surgeon and investigator, respectively, and adjudicated by an Independent Data Monitoring Committee, using an objective scale based on blood loss, transfusion requirements and postoperative bleeding and oozing. Treatment success (primary endpoint) was determined using a composite assessment algorithm and was formally assessed. Results: Surgical prophylaxis with wilate® was successful in 29 of 30 procedures. The overall rate of success was 96.7% (98.75% CI: 0.784, 1.000). All 21 surgeries in patients with VWD Type 3 were managed successfully. There was no accumulation of VWF or FVIII after multiple dosing, and no thromboembolic events or inhibitors to VWF or FVIII were observed. Conclusions: Wilate® demonstrated effective prevention and treatment of bleeding in inherited VWD patients undergoing surgery, with no clinically significant safety concerns. © 2016 The Authors. Haemophilia Published by John Wiley & Sons Ltd.