Monoclonal antibodies represent a significant proportion of biologics in the pharmaceutical industry. Antibodies or immunoglobulins (Ig) are complex molecules about 150 kDa in size that are produced by mammalian cells in dedicated bioreactors. As the product can become infected with viruses during the production process, it is necessary to ensure their removal in the downstream processes. Thus, viruses are removed by chromatography steps, virus inactivation and virus filtration procedures. The latter can be performed in 2 ways, as direct (DFF) or as tangential filtration (TFF). In our case, direct filtration was performed, with which we wanted to compare the virus filtration steps on a production and laboratory scale. The laboratory test was performed under the same conditions as on production scale, using filters of the same type and manufacturer. A pressure vessel was used for the experiment and it was adjusted at constant pressure with a digital manometer. The filtrate was collected in a beaker and its mass was monitored using a balance. The samples were measured for pH, conductivity, concentration, content of aggregated mAbs, content of acidic and basic variants of mAbs, percentage of purity of mAbs, content of other variants of mAbs and calculated step yields. The data was compared using a t-test and the averages of the laboratory scale results were compared with the 3SD intervals of the production scale results. We proved that the process of virus filtration on a laboratory scale is comparable to the process on a production scale for parameters pH, conductivity, aggregate content, percentage of purity, acid and basic mAb variants and mAb 2 variants content. For parameters concentration, step yields, mAb 1 variants and mAb 3 variants content, a statistically significant difference between the data obtained in the laboratory and production scale was found.
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