Three Viresolve Pro Micro devices were tested for each MAb. The MAb 1 solution was approximately 6.0 g/L protein concentration.
The MAb 2 solution was approximately 4.5 g/L protein concentration. After adding a 1% v/v MMV virus spike, feeds were filtered
through a 0.22 µm filter. As can be seen from the results obtained with MAb 2, even at 90% flow decay, no passage of MMV was
observed. With MAb 1, no passage of MMV was observed even after 13 kg/m2 of the protein was challenged. It was not possible to run to such high flow decays with MAb 1, because adequate feed material
was not available. The results presented in Table 2 demonstrate robust virus clearance performance across a range of volumetric
loadings, mass loadings, and flow decay points.
Figure 7 shows capacity performance of Viresolve Pro Micro devices on 16 proteins tested. Most feed streams were tested at
30 psig (2.1 bars) using constant pressure operation. No prefiltration was used except the industry standard practice of a
sterilizing grade filter. The achieved protein mass capacity averaged 6,900 g/m2 when limited to 4 h processing time and 75% flow decay. The results demonstrate achievement of high mass capacities and
short processing times with Viresolve Pro devices.
Further, the BGT has been developed as a new, proprietary release test that uses a two- component gas mixture, in which there
is a large difference in permeability between the two gases across a wetted membrane and concentration is measured on the
downstream side. A deviation from the expected concentration is an indication of the presence of a defect that could negatively
affect the virus-retention capabilities of the device. Data presented in Table 3 demonstrates the superior sensitivity of
this test in comparison to the traditional air-water flux test. Three devices, constructed from the same membrane lot, were
tested with air-water diffusion, BGT, and virus retention testing. Although the BGT could discriminate among devices with
small differences in retention, the air-water diffusion test could not.
In summary, the Viresolve Pro Solution can provide high capacities and high viral retention under a range of processing conditions.
This performance allows for increased productivity in manufacturing operations, often reduces the system size required for
manufacturing. The flexibility of the fully disposable devices allows for ease of use and speed in process development and
manufacturing. Enhanced release testing delivers a higher degree of virus-retention assurance.