The case records of 13 patients (24 pregnancies) with von Willebrand's disease (vWD) were studies rettospectively. The overall incidence of primary and secondary post-partum haemorrhage (PPH) was 15.8% and 25% respectively, all primary PPH occurring in tyre 2 discase (3/14 deliveries, 21.4%). The risk of primary PPH in type 2 patients who did not receive prophylactic factor VIII was 37.5% (3/8 deliveries). Factor VIII coagulant activity (VIII:C) and von Willebrand factor antigen (vWF:Ag) rose above bascline values by a factor of at least 1.5 during the pregnancy in most case. More severely affected patients were less likely to benefit significatntly. A baseline VIII:C of <15 iu/dl (4/14 cases) was predictive of a third trimester level of <15 iu/dl. Improvements in the von Willebrand factor activity were less marked. The baseline von Willebrand factor activity was <15 iu/dl in all patients with serial data, none of whom achieved a third-trimester von Willebrand factor activity of >50 iu/dl. The bleeding times were unaltered significantly in all but one of the cases, reflecting a general failure of the primary haemostatic defect to improve with pregnancy. The findings demonstrate that coagulation parameters do not universally improve in pregnancy in vWD, especially when preconception levels are low. The risk of primary PPH is generally higher in type 2 diseases. The level of factor VIII:C is not a good predictor of the risk of primary PPH in type 2 patients. Secondary PPH is a significatnt risk in both type 1 and type 2 patients.

The safety and efficacy of adjusted continuous infusion (CI) of recombinant factor IX (FIX; BeneFix) was assessed in vitro and in a clinical study. BeneFix was reconstituted at 100 IU mL-1 with or without unfractionated heparin (4 U mL-1) and stored at either 4 degrees C or room temperature. Reconstituted BeneFix retained at least 90% activity over 14 days if stored at 4 degrees C but stability was reduced at room temperature. BeneFix reconstituted in a sterile pharmacy was free of bacterial contamination. Six patients with haemophilia B received seven CIs of BeneFix to cover routine surgery and severe bleeding episodes. The CIs lasted between 3 and 10 days. In all cases, haemostasis was excellent and the desired therapeutic FIX level was easily maintained. No thrombotic episodes or inhibitor development occurred but two patients developed thrombophlebitis at the infusion site when heparin was not added to the infusion. BeneFix is not currently licensed for CI and we suggest that studies to enable licensing should be established as soon as possible.

This prospective, multicentre, open-label study evaluated the efficacy and safety of a plasma-derived factor IX concentrate [Mononine, Coagulation Factor IX (Human) Monoclonal Antibody Purified] administered by continuous intravenous (CIV) infusion to patients with haemophilia B. Admission criteria included documented diagnosis of haemophilia B (mild, moderate, or severe). Twenty-eight patients (25 surgery, two trauma, one severe spontaneous haemorrhage) were enrolled to receive a therapeutic bolus dose followed by CIV infusion of factor IX (FIX) to maintain FIX:C plasma levels of 0.4-1.0 IU mL(-1) (i.e. 40-100%). A median intravenous bolus dose of 54.2 IU kg(-1) FIX was administered to a subset of 13 non-emergency patients 7-21 days prior to CIV infusion to determine pharmacokinetic parameters in order to guide the dosing for CIV. For treatment, a bolus injection (median FIX dose; 89.6 IU kg(-1)) (range, 12.4-108.3), followed by a median total CIV infusion dose of 396.4 IU kg(-1) (range, 44.9-785.5) was administered at a median rate of 3.84 IU kg(-1) h(-1) (range, 1.74-7.33) for 107.17 h (range, 31.75-144). Twenty-four patients completed 72-120 h of FIX CIV infusion. Overall, 'excellent' (i.e. achievement of normal haemostasis) efficacy was reported in 23 of 24 (96%) evaluable patients, and 'good' (i.e. slight oozing) efficacy was reported in one (4%) patient. Median FIX:C was 72-86% for all patients receiving FIX by CIV on all days. Nine patients reported 13 adverse events that were possibly related to study medication but were not deemed serious by the investigator and were mainly because of local irritation at the infusion site. FIX CIV infusion therapy is safe and effective in the treatment of haemophilia B patients undergoing surgery, exposed to trauma, or experiencing severe spontaneous haemorrhage.