PB1415 - Use of recombinant von Willebrand factor concentrate for peri-partum haemostatic management of women with type 2 VWD; a case series

Background: Recombinant VWF concentrate (rVWF) ensures adequate replacement of VWF activity without accumulation of FVIII.

Aims: We describe a case series of three women who were treated with recombinant VWF.

Methods: Pharmacokinetic studies were performed at 32-34 weeks gestation. VWF:RiCo, VWF:Ag, FVIII were assessed pretreatment, 30 minutes, 3, 6, and 24 hours post-infusion.

Results: Two women had type 2M and one had 2B VWD.All women received 60iu/kg rVWF. Mean pre-treatment levels of VWF:Rico, VWF:Ag, FVIII were 14, 90, 50, 137IU/dL respectively. Pharmacokinetic studies showed 736% increase in VWF:RiCo (mean 103IU/dl) at 30 mins and dropped by 2,14,32% (mean 101, 87, 59IU/dL) at 3,6,24 hours, respectively. VWF:Ag increased by 92% (mean 173IU/dL) at 30 mins, followed by 2, 1 and 11% reduction at 3, 6 and 24 hours post-treatment (mean 170, 168 and 158IU/dL). Factor VIII did not change at 30 mins and rose by 17, 1 and 25% at 3, 6 and 24 hours (mean 160, 162 and 203 IU/dL) (Figure 1). Two women had planned a Caesarean section with spinal anaesthesia without any complications. One woman with type 2B VWD developed thrombocytopenia; platelet count was 32x109/L when she attended in labour at 38 weeks. Due to platelet clumping and difficulty obtaining an accurate level, emergency Caesarean section was performed with general anaesthesia. She developed uterine atony and postpartum haemorrhage (1500 ml). rVWF was stopped by 2 weeks post-partum. All women were also given tranexamic acid for 6 weeks.

Conclusion(s): Recombinant VWF concentrate has provided adequate peripartum haemostasis while preventing rise of FVIII in the first 24 hours after delivery when VTE risk is highest.