Optimization of multi-column chromatography for capture and polishing at high protein load.

Abstract

Integrated Continuous Biomanufacturing reduces manufacturing costs while maintaining product quality. A key contributor to high biopharmaceutical costs, specifically monoclonal antibodies (mAbs), is chromatography. Protein A ligands are usually preferred but still expensive in the manufacturing context, and batch chromatography under-utilizes the columns' capacity, compromising productivity to maintain high yields. Continuous chromatography increases columns' Capacity Utilization (CU) without sacrificing yield or productivity. This work presents the in-silico optimization of a 3 Column Periodic Counter-current Chromatography (3C-PCC) of a capture and polishing step for mAbs from a high titer harvest (c_mAb = 5 g/L). The 3C-PCC was modeled and Pareto-fronts for continuous and batch modes were used to optimize the 3C-PCC steps varying the flow rate and percentage of breakthrough achieved in the interconnected loading, maximizing Productivity and CU, for varying concentrations of mAb (batch mode concentration of 5 g/L and continuous mode concentration of 2.5, 5, 7.5, and 10 g/L). The shape of the breakthrough curve significantly impacts the optimization of 3C-PCC. The model output was validated for three different protein A ligands using a pure mAb solution. MAb Select SuRe pcc was selected to continuously capture mAb from a high-titer clarified cell culture supernatant (harvest). The product eluates were pooled and used for continuous polishing using a Cation-Exchange resin (CaptoS ImpAct). Experimental results validated model predictions (<7% deviation in the worst case) and a process with two 3C-PCC in sequence was proposed, with a productivity of approximately 100 mg/mL res/h.