Industrial Platform for Purifying Influenza Virus Particles (Comparison)
Avir Green Hills Biotechnology is developing innovative seasonal and pandemic influenza vaccines based on the deletion of the NS1 gene (del NS1 vaccine).The vaccine is replication-defective and applied intranasally. Recently,clinical phase I studies for H1N1 monovalent vaccine and H5N1 avian influenza vaccine were completed. Both were confirmed to be safe and immunogenic for humans. A production and purification process, which was successfully employed for the pilot-scale production of H1N1 and H5N1 influenza A vaccine virus, will be presented and compared to standard ultracentrifugation method. Details on obtained life virus yields as well as impurity removal will be given. The vaccine virus is produced in static cell culture using Vero (African Green monkey kidney) cells. After clarification the vaccine virus bulk is purified using the same(chromatography-based) scheme for all different subtypes: Concentration by tangential ultrafiltration, AEX chromatography using a CIM QA monolith, and an SEC polishing step allowing for buffer exchange. This purification scheme guarantees the thorough depletion of host cell DNA and total protein. For the ultracentrifugation approach chromatographic steps were replaced by a gradient ultracentrifugation step, comparison data are shown. In addition, an HPLC method for quantifying influenza virus in the vaccine with the use of CIM monolithic columns will be presented and the results will be compared with haemagglutination method.