Viral clearance using disposable systems in monoclonal antibody commercial downstream processing.

Once highly selective protein A affinity is chosen for robust mAb downstream processing, the major role of polishing steps is to remove product related impurities, trace amounts of host cell proteins, DNA/RNA, and potential viral contaminants. Disposable systems can act as powerful options either to replace or in addition to polishing column chromatography to ensure product purity and excellent viral clearance power for patients' safety. In this presentation, the implementation of three disposable systems such as depth filtration, membrane chromatography, and nanometer filtration technology in a commercial process are introduced. The data set of viral clearance with these systems is presented. Application advantages and disadvantages including cost analysis are further discussed.

pH-conductivity hybrid gradient cation-exchange chromatography for process-scale monoclonal antibody purification.

The commercial production of recombinant human monoclonal antibody therapeutics demands robust processes. In this article we describe the development of a pH-conductivity hybrid gradient for a cation-exchange chromatography step to obtain high binding capacity and consistent purification resolution in scale process. Operational parameters and their ranges were characterized with DOE statistical method. Aggregate, DNA and leached protein A removal were examined during development. The advantages and disadvantages of hybrid gradient elution compared to sodium chloride gradient elution were explored. As this step was designed as a good fit for the compatibility of the feed and operating pH/conductivity conditions for next step, the effects of elution by either changing sodium chloride concentration or changing pH of elution buffers on overall separation efficiency were compared. The operation condition was further confirmed in six 2000 L scale runs. The thorough evaluation demonstrated process reliability of hybrid gradient cation-exchange chromatography with high step purity and yield.

New Q membrane scale-down model for process-scale antibody purification.

Process-scale antibody production requires polishing steps with extremely high product throughput and robust operation. In this communication, the Sartobind Q membrane adsorber for process-scale antibody production is evaluated as an alternative to Q column chromatography. Although the capacity seen with large-scale membrane adsorbers is competitive with column chromatography, the same throughput is not achieved with the current scale-down models. The operational issues currently found in membrane scale-down models, including backpressure, which significantly compromises the membrane's capacity, were examined. A new scale-down model was designed to mimic the liquid flow path found in the large-scale capsule, and a new process capacity equivalent at both small and large scale was successfully achieved. Results of a 4-model virus study with a redesigned Sartobind Q absorber scale-down model at the new process capacity are presented.