To clinically validate previously reported stability experience and describe the utilization of continuous infusion (CI) factor VIII (FVIII) replacement therapy with turoctocog alfa for the management of an acute bleeding episode in a patient with hemophilia A.
A 46-year-old woman who belongs to a kindred of women who display a unique dominant inheritance pattern of hemophilia A, with baseline FVIII 4% presented with a right thigh posterior compartment hematoma. After initial bolus administration, on hospital day 2 the hematology consult service initiated a continuous infusion of turoctocog alfa at an initial rate of 4 units/ kilogram/ hour (u/kg/hr), to maintain 100% factor VIII replacement. The syringe containing the recombinant FVIII (rFVIII) concentrate was changed approximately every 8 hours with a maximum 10-hour stability according to published data. When FVIII activity levels were suboptimal, intermittent standard bolus infusions were administered and the rate of the continuous infusion was increased incrementally. The FVIII activity level was measured using the one stage aPTT based clotting assay with STA PTT-Automate reagent on a STAGO model STAR Max.
On hospital days 2 though 6, FVIII activity ranged 55% to 131%. By hospital day 8 the Factor VIII level climbed suddenly to above 200%, and the patient demonstrated marked clinical improvement of the hematoma. Also, on hospital day 8, her course was complicated by development of an upper extremity superficial venous thrombosis with associated cellulitis at an IV access site, which were treated by IV removal and antibiotics. The decision was made to complete the remainder of a planned fourteen-day course of rFVIII as an outpatient. The CI was stopped to allow the FVIII activity level to drop below 80%, and subsequently restarted at a lower rate to maintain a level of at least 50% until patient discharge on Day 11. The turoctocog alfa was not restarted during the remainder of the hospitalization as FVIII level remained above 50%. She had continued clinical resolution of the hematoma and returned to usual activities including moderate exercise after several weeks.
The safety and efficacy of turoctocog alfa via bolus injection is supported by the guardianTM trials. This report describes the successful use of CI turoctocog alfa for management of an acute severe bleed and confirms prior stability data. Our patient’s massive hematoma was effectively managed with CI FVIII replacement with turoctocog alfa during her hospitalization. This case highlights the need for close monitoring of FVIII activity and adjustment of CI dosing and illustrates the challenges and potential complications of an unexpected rise in FVIII activity. Reporting of case experiences are crucial to guide future use. Use of CI factor replacement ensures efficient use of expensive resources and effective treatment of acute and surgical bleeds.