Helixate® FS
Antihemophilic Factor (Recombinant)
Formulated with Sucrose
DESCRIPTION
Helixate® FS Antihemophilic Factor (recombinant) is a sterile, stable,
purified, nonpyrogenic, dried concentrate that has been manufactured using recombinant
DNA technology. Helixate FS (antihemophilic factor recombinant) is intended for use in the treatment of classical
hemophilia (hemophilia A), and is produced by Baby Hamster Kidney (BHK) cells
into which the human factor VIII (FVIII) gene has been introduced.1
The cell culture medium contains Human Plasma Protein Solution (HPPS) and recombinant
insulin, but does not contain any proteins derived from animal sources. Helixate
FS is a highly purified glycoprotein consisting of multiple peptides including
an 80 kD and various extensions of the 90 kD subunit. It has the same biological
activity as FVIII derived from human plasma. Compared to its predecessor product
HELIXATE® Antihemophilic Factor (Recombinant), Helixate FS (antihemophilic factor recombinant) incorporates
a revised purification and formulation process that eliminates the addition
of Albumin (Human).
The purification process includes an effective solvent/detergent virus inactivation step in addition to the use of the classical purification methods of ion exchange chromatography, monoclonal antibody immunoaffinity chromatography, along with other chromatographic steps designed to purify recombinant FVIII and remove contaminating substances.
Additionally, the manufacturing process was investigated for its capacity to
decrease the infectivity of an experimental agent of transmissible spongiform
encephalopathy (TSE), considered as a model for the vCJD and CJD agents.15-27
Several of the individual production and raw material preparation steps in the
Helixate FS (antihemophilic factor recombinant) manufacturing process have been shown to decrease TSE infectivity
of that experimental model agent. TSE reduction steps included the Fraction
II+III separation step for Human Plasma Protein Solution (6.0 log10)
and an anion exchange chromatography step (3.6 log10). These studies
provide reasonable assurance that low levels of CJD/vCJD agent infectivity,
if present in the starting material, would be removed.
Helixate FS (antihemophilic factor recombinant) is formulated with sucrose (0.9–1.3%), glycine (21–25 mg/mL), and
histidine (18–23 mM) as stabilizers in the final container in place of Albumin
(Human) as used in HELIXATE, and is then lyophilized. The final product also
contains calcium chloride (2–3 mM), sodium (27–36 mEq/L), chloride (32–40 mEq/L),
polysorbate 80 (64-96 µg/mL), and trace amounts of imidazole, tri-n-butyl phosphate,
and copper. The product contains no preservatives. The amount of sucrose in
each vial is 28 mg.(250, 500, and 1000 IU sizes) and 56mg. Intravenous administration
of sucrose contained in Helixate FS (antihemophilic factor recombinant) will not affect blood glucose levels. Each
vial of Helixate FS contains the labeled amount of recombinant FVIII in international
units (IU). One IU, as defined by the World Health Organization standard for
blood coagulation FVIII, human, is approximately equal to the level of FVIII
activity found in 1 mL of fresh pooled human plasma. Helixate FS (antihemophilic factor recombinant) must be administered
by the intravenous route.
REFERENCES
1. Lawn RM, Vehar GA: The molecular genetics of hemophilia. Sci Am 254(3):48–54,
1986.
15. Kimberlin RH, Walker CA: Characteristics of a short incubation model of
scrapie in the golden hamster. J Gen Virol 34(2):295-304, 1977.
16. Kimberlin RH, Walker CA: Evidence that the transmission of one source of
scrapie agent to hamsters involves separation of agent strains from a mixture.
J Gen Virol 39(3):487-96, 1978.
17. Kimberlin RH, Walker CA: Pathogenesis of scrapie (strain 263K) in hamsters
infected intracerebrally, intraperitoneally or intraocularly. J Gen Virol 67(2):255-63,
1986.
18. Prusiner SB, et al: Further purification and characterization of scrapie
prions. Biochemistry 21(26):6942-50, 1982.
19. Kascsak RJ, et al: Mouse polyclonal and monoclonal antibody to scrapie-associated
fibril proteins. J Virol 61(12):3688-93, 1987.
20. Rubenstein R, et al: Scrapie-infected spleens: analysis of infectivity,
scrapie-associated fibrils, and protease- resistant proteins. J Infect Dis
164(1):29-35, 1991.
21. Taylor DM, Fernie K: Exposure to autoclaving or sodium hydroxide extends
the dose-response curve of the 263K strain of scrapie agent in hamsters.
J Gen Virol 77(4):811-13, 1996.
22. Stenland CJ, et al: Partitioning of human and sheep forms of the pathogenic
prion protein during the purification of therapeutic proteins from human plasma.
Transfusion 42(11):1497-500, 2002.
23. Lee DC, Miller JL, Petteway SR: Pathogen safety of manufacturing processes
for biological products: special emphasis on KOGENATE® Bayer. Haemophilia
8(Suppl. 2):6-9, 2002.
24. Lee DC, Stenland CJ, Hartwell RC, et al: Monitoring plasma processing steps
with a sensitive Western blot assay for the detection of the prion protein.
J Virol Methods 84(1):77-89, 2000.
25. Lee DC, Stenland CJ, Miller JL, et al: A direct relationship between the
partitioning of the pathogenic prion protein and transmissible spongiform encephalopathy
infectivity during the purification of plasma proteins. Transfusion 41(4):449-55,
2001.
26. Cai K, Miller JL, Stenland CJ, et al: Solvent-dependent precipitation of
prion protein. Biochim Biophys Acta 1597(1):28-35, 2002.
27. Trejo SR, Hotta JA, Lebing W, et al: Evaluation of virus and prion reduction
in a new intravenous immunoglobulin manufacturing process. Vox Sang 84(3):176-87,
2003.