It is important to ensure that conditions used during processing are within the parameters used during the scaled-down virus
retention assessment studies. Because most parvovirus retentive filters exhibit a decline in virus retention ability with
flow decay, it is important to ensure that flow decay during processing is comparable to that observed during retention studies.
Other parameters to be monitored during processing include solution conditions, volumetric throughput, and post-production
Virus filtration is a critical component in the manufacture of biological therapeutics. Implementation of a virus retentive
filter is one of many steps a manufacturer will take to ensure product safety. The choice of a virus filter is driven mainly
by robust virus retention. Nevertheless, robust retention should be achieved as economically as possible. This brief overview
of regulatory-, process-, and filter-related considerations should aid filter users in selecting the right virus filter and
in initiating filter optimization studies.
Gerd Kern is technology manager, virus management solutions, for Millipore SAS, 39, route industrielle de la Hardt, 67120 Molsheim,France, +33.(0).188.8.131.52.00, fax: +33.(0).184.108.40.206.93, firstname.lastname@example.org
Mani Krishnan is program manager, virus and biomolecular clearance, for Millipore Corporation, 80 Ashby Road, Bedford, MA 01730, 800.645.5476, fax: 800.645.5439, email@example.com
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