Achieving high mass‐throughput of therapeutic proteins through parvovirus retentive filters

Abstract

Parvovirus retentive filters that assure removal of viruses and virus-like particles during the production of therapeutic proteins significantly contribute to total manufacturing costs. Operational approaches that can increase throughput and reduce filtration area would result in a significant cost savings. A combination of methods was used to achieve high throughputs of an antibody or therapeutic protein solution through three parvovirus retentive filters. These methods included evaluation of diatomaceous earth or size-based prefilters, the addition of additives, and the optimization of protein concentration, temperature, buffer composition, and solution pH. An optimum temperature of 35°C was found for maximizing throughput through the Virosart CPV and Viresolve Pro filters. Mass-throughput values of 7.3, 26.4, and 76.2 kg/m(2) were achieved through the Asahi Planova 20N, Virosart CPV, and Viresolve Pro filters, respectively, in 4 h of processing. Mass-throughput values of 73, 137, and 192 kg/m(2) were achieved through a Millipore Viresolve Pro filter in 4.0, 8.8, and 22.1 h of processing, respectively, during a single experiment. However, large-scale parvovirus filtration operations are typically controlled to limit volumetric throughput to below the level achieved during small-scale virus spiking experiments. The virus spike may cause significant filter plugging, limiting throughput. Therefore newer parvovirus filter spiking strategies should be adopted that may lead to more representative viral clearance data and higher utilization of large-scale filter capacity.

The effects of buffer condition on the fouling behavior of MVM virus filtration of an Fc‐fusion protein

“…Viral filtration is one of the most expensive steps during the downstream processing of therapeutic proteins (G. R. Bolton, Basha, & LaCasse, 2010). Viral filtration is one of the most expensive steps during the downstream processing of therapeutic proteins (G. R. Bolton, Basha, & LaCasse, 2010).…”

Interactions between protein molecules and the virus removal membrane surface: Effects of immunoglobulin G adsorption and conformational changes on filter performance

“…Decreased throughput due to membrane fouling during the production processes is another critical issue in virus filtration . Membrane fouling is commonly observed regardless of filter type and two main causes for the related decline in filter performance have been proposed . First, the adsorption of proteins onto a wide variety of membrane surfaces (caused by protein‐surface interaction) reduces the effective size of the membrane pores and causes caking on the membrane surface.…”

Adapting viral safety assurance strategies to continuous processing of biological products

“…Therefore, when designing any viral filtration into a continuous flow‐through process, product specific factors, such as buffer pH, conductivity, pressure, or flow rates and their effect on viral filter retention must be considered. Potential frameworks for these considerations exist for batch processing (Bolton et al, ; Dishari et al, ; Hongo‐Hirasaki et al, ) that may be utilized in designing continuous viral filtration methods or when performing validation studies. As with batch processing methods, integrating any novel or adapted viral filtration into a continuous flow‐through polishing process will require validation of clearance, but often this can be performed as an isolated unit in batch mode.…”

“…The utilization of novel polishing processes, such as the charcoal based process seen in a case study by Gillespie et al () may increase the pressure and load limitations of viral filters in a CP. Another step utilized in batch processes to mitigate filter fouling and extend their lifetimes, is the use of pre‐filtration devices prior to utilizing viral filters in the purification process (Bolton et al, , ; Brown et al, ; Challener, ) which can be utilized based on evaluated bioburden limits of the filters chosen (Yang et al, ). The potential for these technologies is discussed elsewhere in this review, but these would also require periodic switch out as well.…”