Design of experiments-guided membrane capture facilitates integration of continuous virus inactivation using Phi6 as a surrogate virus in an intensified downstream process.

The growing demand for cost-efficient and flexible biomanufacturing has increased interest in process-intensified downstream platforms. This study evaluates an intensified monoclonal antibody (mAb) purification sequence, where two unit operations traditionally performed in batch mode-Protein A capture and low pH virus inactivation (VI)-are redesigned to enhance productivity and minimize resource usage. Rapid-cycling Protein A membrane chromatography was optimized using a design-of-experiments approach to address inherent membrane challenges such as buffer consumption. Wash step volumes were systematically reduced without compromising host cell protein or host cell DNA clearance, yielding a 70% reduction in total wash buffer consumption. At manufacturing scale, membrane adsorbers achieved critical quality attributes comparable to a benchmark resin, while increasing productivity ~20-fold and lowering capture-step costs. Protein A eluates were processed in a novel continuous virus inactivation (cVI) system using bacteriophage Phi6 as a surrogate for enveloped viruses. At residence times of 35 and 70 min, the cVI system achieved a ≥5-log reduction, equaling conventional batch performance without compromising mAb quality. The study demonstrates that membrane-based Protein A capture and continuous VI can be seamlessly integrated into an intensified DSP framework. This approach effectively maintains product quality while significantly reducing buffer usage and cost, thus supporting modular intensification strategies for clinical-scale mAb manufacturing.