Journal of Bioequivalence & Bioavailability

Production and functional characterization of recombinant clotting factor VIII

International Conference and Exhibition on Biowaivers & Biosimilars

September 10-12, 2012 Hilton San Antonio Airport, USA

Molina ES, Sogayar MC and Demasi MAA

Posters: J Bioequiv Availab

Abstract:

Human recombinant clotting factor VIII (rhFVIII) is used for replacement therapy in prevention and treatment of Hemophilia A. In order to improve the production yield of rhFVIII in mammalian cells, we produced an engineered version of this construct (rFVIII-NUCEL) and expressed it in a genetically engineered CHO-DG44 cell line. Since versions of FVIII containing juxtaposed new amino acid sequences may produce dissimilarities in efficacy and safety, we produced and assessed the bioavailability of rhFVIII through in vivo and ex vivo assays, compared to the reference product (Kogenate, Bayer). Concentrated rhFVIII-NUCEL was injected into hemophilic mice (strain B6; 129S4F8tm1kaz/J) to assess the in vivo FVIII activity by the tail bleeding assay. The results showed that the hemophilic phenotype was reversed in 5/5 animals evaluated with doses above 50 IU/Kg body weight, similarly to the 5/5 result observed in animals treated with Kogenate and differently from 0/10 animals treated with saline, noting that normal clotting phenotype was found in 5/5 wild type (WT) animals (strain 129/J). The FVIII ex vivo activity was estimated in plasma samples of hemophilic mice previously treated with rhFVIII reference product, determining that ex vivo activity found in plasma of animals which received 50 IU/Kg was 610?160 mIU/ml, value estimated to be 63% of that found in WT (1084?137 mIU/ml). These results indicate that our rhFVIII-NUCEL displays prompting its further characterization. The future perspectives include purification of rhFVIII-NUCEL to assess its in vivo and ex vivo bioavailability, as well as its immunogenicity profile when compared with reference product