Author Archives: Patricia Greenhalgh

Prefiltration and Process Improvements: Enhancing Virus Filter Performance with the Use of Adsorptive Depth or Surface Modified Prefilters

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Improvements in upstream process development often generate complex, high titer process streams, placing considerable demands on downstream processing steps. Protein aggregates in these feeds influence hydraulic performance of virus filters resulting in over-sized platforms and a significant impact on process economics. Virus filters from a broad range of manufactures provide robust viral clearance but the impact of aggregates on flux is dependent on the filter. The impact of conditioning protein solutions using prefiltration was assessed with several monoclonal antibody feed…

December 20, 2016

Impact of Process Interruption on Virus Retention of Small-Virus Filters

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Manufacturers of biopharmaceuticals using mammalian cell culture must have processes in place to minimize the likelihood of virus contamination of their products. Regulatory agencies provide guidelines for testing strategies and best practices to assure raw-material safety and control of the manufacturing process. Safety assurance relies on an interdependent matrix of managed risks, including characterization and control of raw materials, extensive testing of process intermediates, and demonstration of the virus removal capabilities of purification unit operations Figure 1:  () A dedicated…

November 1, 2013

Predicting Virus Filtration Performance with Virus Spike Characterization

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Evaluating a virus filter should, in theory, be a straightforward exercise. Membrane-based filtration is a robust virus reduction technology that plays an important role in virus safety for most drug production processes. An appropriate virus filter for a given process is generally selected through preliminary testing with relevant drug feed material. Data acquired during such tests are used to determine hydraulic performance targets such as expected flow rates and total throughputs. A virus clearance evaluation study is then performed in…

March 1, 2011