Production processes of licensed recombinant factor VIII preparations

The state-of-the-art treatment for hemophilia A is replacement therapy with recombinant factor VIII (rFVIII) made possible by genetic engineering advances. Currently, there are four different products licensed and available for hemophilia A patients. All are produced by recombinant mammalian cells in large-scale fermenter cultures, purified to high purity, formulated in stable formulations and freeze dried. The first-generation products Recombinate and Kogenate (also sold as Helixate by Aventis) are characterized as full-length human factor VIII molecules and formulated using human serum albumin as a stabilizer. The second-generation product ReFacto contains an improved albumin-free sucrose formulation and incorporates advanced antiviral safety procedures in the manufacturing process. It is a truncated B region-deleted form of factor VIII (FVIII) that makes use of a nonhuman peptide linker 14 amino acids in length to connect the 80 and 90 kD subunits. The most recently licensed rFVIII product is the second-generation Kogenate product called KOGENATE Bayer/Kogenate FS, which combines the advantages of the human full-length FVIII molecule with an albumin-free, sucrose-based synthetic formulation as well as an improved viral safety profile. In this article, the manufacturing processes for each of the four different products are discussed in detail, focusing on expression systems and cell lines, culture medium, technical culture systems, purification process (including viral removal potential), and final formulation.