Objective:
To evaluate efficacy of IB1001 for perioperative management of bleeding under surgical circumstances in hemophilia B patients.
Methods:
The efficacy of IB1001 for perioperative management has been evaluated in a prospective, open-label, multicenter international study where 17 subjects (16 male PTPs and one female hemophilia B carrier) underwent 20 major surgical procedures. The PTPs were defined as patients with a minimum of 150 exposures to another factor IX preparation. The subjects had severe or moderately severe (factor IX level ≤ 2 IU/dL) hemophilia B without inhibitors, with exception of one mild hemophilia B female carrier. Efficacy of IB1001 was based on the surgeon’s assessment including estimation of blood loss as ‘less than expected’, ‘expected’, or ‘more than expected’ at the time of surgery and assessment of hemostasis at 12 and 24 hours post-surgery as ‘superior’, ‘adequate’, or ‘poorly controlled’. Transfusion requirements were also monitored.
Summary:
Thirteen major procedures in 12 male subjects were managed by bolus regimen, and 6 major procedures in 4 male subjects were managed by continuous infusion regimen. Mean loading dose for 13 major procedures managed by bolus regimen was 120 ± 11.4 IU/kg and mean maintenance bolus dose (given every 12 hours) was 59.7 ± 12.2 IU/kg. During the 24 hours following surgery, factor IX levels were successfully maintained over 60%, as intended. Factor IX levels at pre-infusion were 59.7% ± 15.9% at 12 hours after surgery and 54.4% ± 16.5% at 24 hours after surgery. For a major procedure in one female carrier, the bolus dose was 110 IU/kg, while the mean maintenance dose was 44.9 ± 7.0 IU/kg. Mean loading dose for 6 major procedures managed by continuous infusion regimen was 95.4 ± 14.5 IU/kg and the mean maintenance infusions were 7.1 ± 4.0 IU/kg/hr. In all major procedures, blood loss at the time of surgery was ‘expected’ or ‘less than expected’ as assessed by the surgeon. IB1001 was rated by the surgeon as ‘superior’ or ‘adequate’ in controlling hemostasis post-surgery, including 8 knee arthroplasties, two elbow arthroplasties, one knee amputation, one percutaneous Achilles tendon lengthening, one open inguinal hernia repair, one tibiotalar fusion, two arthroscopic synovectomies, three debridements and one total hysterectomy/bilateral oopherectomy. There were no transfusions required perioperatively.
Conclusions:
At the time of surgery, blood loss was expected or less than expected after IB1001 treatment, while post-surgery effective hemostasis control was achieved following IB1001 treatment in hemophilia B patients.