US experience with recombinant factor VIIa for surgery and other invasive procedures in acquired haemophilia: analysis from the Hemostasis and Thrombosis Research Society Registry

Introduction Acquired haemophilia (AH) is a rare disorder caused by autoantibodies against factor VIII. Aim The Hemostasis & Thrombosis Research Society (HTRS) Registry was used to monitor the safety of recombinant FVII (rFVIIa). This study aims to report data from the HTRS Registry regarding safety and efficacy of rFVIIa for haemostatic management of surgeries and other invasive procedures in patients with AH. Methods For each rFVIIa-treated procedure, the initial dose, total dose, average infused dose, number of doses and treatment duration were calculated. Efficacy was assessed on a 4-point scale. Results Of 166 registered patients with AH, 37 patients underwent 58 procedures [30 (51%) rFVIIa-treated]. The median (range) age of all patients undergoing procedures was 70 (13–93) years; for rFVIIa-treated patients, 74 (28–89) years. Approximately 67% (39/58) of all procedures were elective. Overall, the most common procedures were endoscopy (12) and central venous access device (10); rFVIIa was used preoperatively (11), postoperatively (13) and during six follow-up procedures during ongoing postoperative rFVIIa treatment. The median (range) initial dose was 90.0 (44–187) μg kg−1 preoperatively and 106.0 (56–270) μg kg−1 postoperatively. For rFVIIa-treated episodes with a reported outcome, 20 (91%) were rated excellent/good or no additional agents used and 2 (9%) were rated as poor/ineffective requiring a switch to another bypassing agent. No thromboembolic events were reported. Conclusions Adequate haemostasis was provided for 91% of rFVIIa-treated procedures at doses largely conforming to the package insert. No safety concerns were reported.