Prevent Postpartum Hemorrhage in Women with Von Willebrand Disease: the VWD-WOMAN Trial

The purpose of this 8-week single center, randomized, open-label phase III trial to compare recombinant von Willebrand factor (rVWF, Vonvendi®)) plus tranexamic acid (TA, Cyclokapron®) vs. rVWF alone to prevent postpartum hemorrhage (PPH) in women with Von Willebrand disease (VWD). VWD is an inherited bleeding disorder that occurs in 1% of the population. It is caused by deficient or defective von Willebrand factor (VWF). Treatment at delivery is with VWF concentrate, based on U.S. and European guidelines, and as DDAVP, a non-VWF protein, is contraindicated as it may cause hyponatremia (low salt) and seizures due to fluid replacement at delivery. Yet, blood loss is 1.5-fold greater in VWD than non-VWD controls. The investigators believe this is due to physiologic (protective) fibrinolysis (clot breakdown) in the first 3 hours after delivery, which may protect controls from excess clotting after delivery, but which may increase bleeding in subjects with VWD. PPH a significant cause of maternal morbidity and mortality in women. PPH is defined as >1000 ml within the first 24 hours of vaginal or cesarean delivery. PPH peaks in the first 2-3 hours postpartum, a time during which there is early activation of the fibrinolytic system, with a 2-fold increase TPA (tissue plasminogen activator). So while uterine atony is the major cause of PPH, accounting for 63% of PPH cases, but in 37% of cases, uterotonic agents fail.

TA is an anti-fibrinolytic therapy (prevents clot breakdown) which reduces bleeding and prevents clot breakdown in surgery, trauma, and in controls at delivery, if it is given within 3 hours of delivery. In the WOMAN trial, a large trial of over 10,000 women without bleeding disorders, TA was safe and effective in reducing PPH when given intravenously (in a vein) within 3 hours of vaginal or cesarean delivery. As TA is approved by the US. Food and Drug Administration (FDA) to treat and prevent bleeding in VWD, the investigators propose to study rVWF plus TA vs. VWF alone to reduce PPH in subjects with VWD. This is a pilot study to determine if recruitment, randomization, and study drug administration can be performed successfully, and shows preliminary safety and efficacy in subjects with VWD. rVWF (Vonvendi®) will be administered by intravenous infusion before delivery and on day 1 and day 2 postpartum. Tranexamic acid (Cyclokapron®) will be administered by intravenous infusion within 3 hours postpartum. Randomization will be at delivery to either rVWF at delivery and on day 1 and day 2 postpartum, plus TA within three hours postpartum; or rVWF alone at delivery and on day 1 and day 2 postpartum.