Efficacy and safety of a VWF/FVIII concentrate in surgical procedures – results from the ongoing study Wilate-STATE

S. Halimeh1, M. Daoud1, M. Rieke2, T. Lang2, J. Kadar3, S. Alesci4, J. Koscielny5, J. Feddern6, S. Seeger6 (1Duisburg, Germany, 2Hohne, Germany, 3Cologne, Germany, 4Bad Homburg, Germany, 5Berlin, Germany, 6Langenfeld, Germany)

Bleeding disorders, coagulation and fibrinolytic factors
Date: 17.02.2017,
Time: 17:15 - 18:15

Objective: wilate® is a double inactivated VWF/FVIII (1:1 ratio) concentrate authorized in Germany since 2005. With the introduction of filling sizes 500 and 1000 IU in 2012, a non-interventional study (NIS) was started in Germany (STATE-Surveillance of tolerability and treatment efficacy). In this study we are aiming to confirm consistency of efficacy and safety data of wilate® used in routine clinical practice with data obtained in previous clinical and post-marketing studies. Probably matching the real-life situation, the predominant reason for administration of wilate® in this study was to prevent bleeding during and after surgery. For this reason, an evaluation of this subgroup was performed of which the results will be presented.

Methods: After obtaining informed consent, patients with hereditary or acquired von Willebrand disease (VWD) of any age requiring replacement therapy are eligible to be included in the study. A thorough documentation of anamnestic data is done before details of all injections in conjunction with the surgeries are documented. Details on the procedures performed and outcome including an efficacy assessment are rated using a 4-point-rating scale according to pre-defined criteria are documented. Depending on the haemostatic challenge, the surgeries are categorized in “minor” or “major” surgical procedures.

Results: Until data lock point, 50 patients underwent surgery. The distribution between the different types of VWD in the surgery group is as follows: 42 (84%) patients have type 1, 7 (14%) type 2 and 1 (2%) acquired VWD. The patients’ age ranges from 8 months to 74 years, including 34 paediatric patients (< 14 years). 13 minor and 37 major surgeries were performed. Adenotomy and tonsillectomy are the most frequently documented surgeries, which are classified as major operations due to their high bleeding risk (58%). In total, 213,000 IU were administered on 125 exposure days (ED) for surgeries. Per ED, a median of 31.2 and 33.3 IU/kg BW respectively for minor and major surgeries were administered (mean 34.0 + 10.9 IU/kg). The efficacy was rated excellent/good in 48 (96%) and moderate in 2 (4%) of cases based on all surgeries. None of the patients experienced an ADR.

Conclusion: The results of this interim analysis confirm the efficacy and safety of the investigated VWF/FVIII concentrate wilate® in managing bleeding prophylaxis during and after surgical procedure.