An updated analysis of viral clearance unit operations for biotechnology manufacturing

Virus filtration process is used to ensure viral safety in the biopharmaceutical downstream processes with high virus removal capacity (i.e., >4 log10). However, it is still constrained by protein fouling, which results in reduced filtration capacity and possible virus breakthrough. This study investigated the effects of protein fouling on filtrate flux and virus breakthrough using commercial membranes that had different symmetricity, nominal pore size, and pore size gradients. Flux decay tendency due to protein fouling was influenced by hydrodynamic drag force and protein concentration. As the results of prediction with the classical fouling model, standard blocking was suitable for most virus filters. Undesired virus breakthrough was observed in the membranes having relatively a large pore diameter of the retentive region. The study found that elevated levels of protein solution reduced virus removal performance. However, the impact of prefouled membranes was minimal. These findings shed light on the factors that influence protein fouling during the virus filtration process of biopharmaceutical production.

Section: Introductionmentioning

confidence: 99%

Effect of protein fouling on filtrate flux and virus breakthrough behaviors during virus filtration process

Suh

Jin

Park

et al. 2023

“…Due to the concern that virus breakthrough to permeate may occur due to the pressure drop during a process pause as previously described (Ajayi et al, 2022; Fan et al, 2021; Johnson et al, 2022), a 60 min process pause was included after loading the virus‐spiked mAb, and virus removability for inline spiking of MVM or X‐MuLV was evaluated for both the flow‐through fraction of the mAb and the flow‐through fraction with the buffer wash. As shown in Table 3 for mAb spiked with MVM or X‐MuLV, complete clearance was achieved for both the flow‐through fraction and the flow‐through plus wash with MVM LRV of ≥5 and X‐MuLV LRV of ≥3. The relatively lower X‐MuLV LRV for the filter than the two‐column process can be attributed to the lower X‐MuLV spike titer.…”

Section: Resultsmentioning

confidence: 99%

Viral clearance in end‐to‐end integrated continuous process for mAb purification: Total flow‐through integrated polishing on two columns connected to virus filtration

Shirataki

Matsumoto

Konoike

et al. 2023

There are few reports of the adoption of continuous processes in bioproduction, particularly the implementation of end‐to‐end continuous or integrated processes, due to difficulties such as feed adjustment and incorporating virus filtration. Here, we propose an end‐to‐end integrated continuous process for a monoclonal antibody (mAb) with three integrated process segments: upstream production processes with pool‐less direct connection, pooled low pH virus inactivation with pH control and a total flow‐through integrated polishing process in which two columns were directly connected with a virus filter. The pooled virus inactivation step defines the batch, and high impurities reduction and mAb recovery were achieved for batches conducted in succession. Viral clearance tests also confirmed robust virus reduction for the flow‐through two‐column chromatography and the virus filtration steps. Additionally, viral clearance tests with two different hollow fiber virus filters operated at flux ranging from 1.5 to 40 LMH (liters per effective surface area of filter in square meters per hour) confirmed robust virus reduction over these ranges. Complete clearance with virus logarithmic reduction value ≥4 was achieved even with a process pause at the lowest flux. The end‐to‐end integrated continuous process proposed in this study is amenable to production processes, and the investigated virus filters have excellent applicability to continuous processes conducted at constant flux.

“…The filters investigated are grouped into first‐ and second‐generation filters (Opeyemi et al, 2022). First generation filters are designed for downstream manufacturing processes.…”

Section: Resultsmentioning

confidence: 99%

Protection of biomanufacturing processes from virus contamination through upstream virus filtration of cell culture media

Wieser

Modrof

Kreil

2023

Cell‐based manufacturing processes have occasionally been exposed to adventitious viruses, leading to manufacturing interruptions and unstable supply situations. The rapid progress of advanced therapy medicinal products needs innovative approaches to avoid any unwelcome reminder of the universal presence of viruses. Here, we investigated upstream virus filtration as a clearance step for any product too complex for downstream interventions. Culture media virus filtration was investigated with respect to virus clearance capacities under extreme conditions such as high process feed loading (up to ~19,000 L/m²), long duration (up to 34 days), and multiple process interruptions (up to 21 h). The small nonenveloped Minute virus of mice was used as relevant target virus, and as worse‐case challenge for the investigated virus filters with a stipulated pore‐size of about 20 nm. Certain filters—especially of the newer second generation—were capable of effective virus clearance despite the harsh regimen they were subjected to. The biochemical parameters for un‐spiked control runs showed the filters to have no measurable impact on the composition of the culture media. Based on these findings, this technology seems to be quite feasible for large volume premanufacturing process culture media preparations.