Hydrophobic Interaction chromatography (HIC) is a powerful polishing tool for the downstream purification and manufacture of biotherapeutics. HIC offers orthogonal selectivity for the clearance of difficult process and product-related impurities such as aggregates, host cell proteins and endogenous and adventitious viruses.  In this study, a family of POROS HIC resins with novel ethyl and benzyl chemistries was used to successfully polish two clinical stage monoclonal antibodies harboring very high levels of product aggregation (>10%). In addition to aggregate removal, viral…