Stability and sterility of a recombinant factor VIII concentrate prepared for continuous infusion administration

Minipumps may facilitate cost-effective and convenient continuous infusion (CI) therapy for severe hemophilia A, This study evaluated the in vitro ste rility, ability to support bacterial growth, and specific activity stabilit y of a recombinant factor VIII (FVIII; Bioclate(TM), Centeon) delivered by simulated CI at a variety of temperatures and after the addition of heparin or antibiotic, Closed system Cls of Bioclate(TM) (89.5 IU/ml) with and wit hout heparin were sampled and cultured over a 6 day period. Bioclate(TM) (5 3.7 IU/ml) with and without heparin or vancomycin was inoculated with 102-1 05 CFU/ml of S. aureus, S. epidermidis, Escherichia coli, E. cloacae, or Y. enterocolitica and assessed by quantitative culture after 1 and 3 days, Th e stability of Bioclate(TM) (50, 100, and 250 IU/ml) at three temperatures (21 degrees C, 37 degrees C, and 39 degrees C) with and without heparin or vancomycin was tested over a period of 28 days, FVIII activity was measured in triplicate by a chromogenic assay (Coamatic(R) Factor VIII, Chromogenix ) and purity evaluated by Western blot. No bacterial growth was detected du ring CI of FVIII for up to 6 days. Following bacterial inoculation, there w as rapid growth (>3 log increase) of all tested bacterial species except S. aureus which only displayed a 1 log expansion at 3 days. The addition of h eparin containing 9.45 mu g/U benzyl alcohol had no effect on bacterial gro wth. The addition of vancomycin caused a modest suppression of S. aureus gr owth but not of E. coli. Diluent alone did not support bacterial growth, Ne ither concentration, increased temperature, nor the addition of heparin or vancomycin had a significant effect on FVIII activity stability. Samples re tained >75% baseline activity for between 3 and 7 days, except the infusion of Bioclate(TM) 50 IU/ml plus heparin maintained at 21 degrees C which rem ained stable far 28 days. Western blot analysis supported the activity assa y findings. Standard and concentrated preparations of Bioclate(TM) are suit able for CI when delivered by the MiniMed(R) 404-SP minipump, Because of th e observed nutritive capability of this FVIII concentrate for sustaining ba cterial growth, any contamination could result in systemic infection. Am. J , Hematol. 62:13-18, 1999. (C) 1999 Wiley-Liss, Inc.