Continuous downstream processing is increasingly evaluated and implemented in the biopharmaceutical industry. For the capture of monoclonal antibodies using protein A affinity chromatography, periodic counter-current processes have been described. While general process principles have been fully understood, the focus has shifted to important manufacturing-related aspects such as scale-up, control and validation.
As part of a process validation procedure, we present an outline of a risk-based model-assisted process characterization approach for the twin column capture process CaptureSMB. The basic procedure uses process description, risk analysis and ranking, parameter testing and statistical analysis as main elements. It is shown how modeling can be used to significantly lower the experimental burden of twin column capture process validation and find optimal process operating ranges.