Publication of data from WIL-31 study marks a milestone in improving long-term care for patients with severe von Willebrand disease (VWD)

• WIL-31 is the largest prospective prophylaxis study in VWD

• WIL-31 is the only study in VWD with a prospective on-demand run-in study as an intra-individual comparator

• wilate^® prophylaxis is highly effective at reducing bleeding rates in children and adults with all types of VWD vs prior on-demand treatment

Octapharma announced today the publication of the results from the clinical study WIL-31, which investigated the efficacy and safety of prophylaxis with wilate^®, a von Willebrand factor/factor VIII (VWF/FVIII) concentrate, in patients with all types of von Willebrand disease (VWD). The results have been published in the leading medical journal Blood Advances. [Sidonio RF Jr et al. “Von Willebrand factor/factor VIII concentrate (wilate^®) prophylaxis in children and adults with von Willebrand disease”]

The lead author and Principal Investigator of the WIL-31 study, Robert F. Sidonio Jr, M.D. (Medical Director of Hemophilia at the Aflac Cancer & Blood Disorders Center with Children’s Healthcare of Atlanta and Associate Professor of Pediatrics at Emory University School of Medicine), commented:

“WIL-31 is the largest prospective study to date examining the efficacy and safety of regular prophylaxis in patients with VWD. Importantly, the study included a diverse patient population, including young children and adults, males and females, and all types of VWD. The findings from WIL-31 provide strong evidence to support the use of VWF prophylaxis and have led to the recent addition of wilate^® prophylaxis as a therapeutic indication for VWD in the US, widening its access to the US patient population.”

The WIL-31 study (NCT04052698) was a prospective, multinational, open-label, non-controlled phase III study assessing wilate^® prophylaxis in preventing bleeds in VWD. Efficacy was assessed in 33 adult and pediatric VWD patients aged 6 years and older from 14 centers in eight countries, with patients receiving wilate^® prophylaxis two or three times weekly for 12 months. All patients had taken part in a prospective 6-month run-in study (WIL-29) during which they received on-demand treatment with any available VWF concentrate, allowing assessment of the efficacy of prophylaxis at an intra-individual level.  

The primary endpoint of the study, >50% reduction in mean total annualized bleeding rate (ABR) during wilate^® prophylaxis compared with prior on-demand treatment, was met. Mean total ABR during wilate^® prophylaxis was 5.2 compared with 33.4 during on-demand treatment, representing a decrease of 84%. Mean spontaneous ABR decreased by 87% during wilate^® prophylaxis compared with on-demand treatment. Reductions in total and spontaneous bleeding were comparable across age groups, bleeding sites and VWD disease types, and between males and females. The majority of patients were dosed twice weekly and the median weekly dose of wilate^® was relatively low (58 IU/kg) compared to the dose range recommended in the prescribing information.  

Seven women with child-bearing potential were included in the study. This allowed the investigators to gain insights into the effect of wilate^® prophylaxis on heavy menstrual bleeding, which is a major problem in women with VWD as there are limited clinical data on effective treatments. Although the data are based on a small sample size, they suggest that wilate^® prophylaxis has a positive impact in reducing heavy menstrual bleeding, with 71% (n=5) patients not experiencing heavy menstrual bleeding during wilate^® prophylaxis.

Prophylaxis with wilate^® was well tolerated across VWD types, in children and adults, and in males and females. During the 12 months of wilate^® prophylaxis, there were no serious adverse events related to wilate^® and no thrombotic events or FVIII accumulation.

“In contrast to haemophilia A, prophylaxis is not standard of care in VWD and less than 10% of patients with severe VWD receive prophylaxis”, said Sigurd Knaub, SVP CR&D Haematology. “This is due in part to the scarcity of data from prospective trials. The results of the WIL-31 study help to fill this gap, providing strong evidence for the benefits of a prophylactic strategy in patients with severe VWD. Increasing the adoption of prophylaxis in VWD is expected to lead to improved outcomes and reduced disease burden for people suffering from VWD.”

Octapharma would like to thank all participating centers, as well as the patients and their caregivers, for their contribution to the study. Further publications on other analyses from the WIL-31 study are planned.

About wilate^®

wilate^® is a high-purity human von Willebrand factor/factor VIII (VWF/FVIII) concentrate, that undergoes two virus inactivation steps during its production¹. No albumin is added as a stabiliser¹. The purification processes result in a 1:1 ratio of VWF to FVIII that is similar to normal plasma¹. wilate^® contains a VWF triplet structure and content of large high molecular weight multimers similar to normal human plasma¹. wilate^® is available in 500 IU and 1,000 IU presentations².

wilate^® is indicated for the prevention and treatment of haemorrhage or surgical bleeding in von Willebrand disease (VWD), when desmopressin (DDAVP) alone is ineffective or contra-indicated, and for the treatment and prophylaxis of bleeding in patients with haemophilia A (congenital factor VIII deficiency)². The indication for prophylaxis in the US is detailed in the updated prescribing information available here: wilate Full Prescribing Information (wilateusa.com)

About Octapharma

Headquartered in Lachen, Switzerland, Octapharma is one of the largest human protein manufacturers in the world, developing and producing human proteins from human plasma and human cell lines.

Octapharma employs more than 11,000 people worldwide to support the treatment of patients in 118 countries with products across three therapeutic areas: Immunotherapy, Hematology, and Critical Care.

Octapharma has seven R&D sites and five state-of-the-art manufacturing facilities in Austria, France, Germany and Sweden, and operates more than 190 plasma donation centers across Europe and the US. Octapharma has 40 years of experience in patient care.

Octapharma press releases are specifically for health specialist/medical media and are not for consumer press. 

References

1. Stadler M et al. Biologicals 2006; 34:281–8.

2. wilate® Summary of Product Characteristics 2023.