Effectiveness of Various Processing Steps for Viral Clearance of Therapeutic Proteins: Database Analyses of Commonly Used Steps

Abstract

The successful implementation of any biologically derived product in human clinical trials and as a marketed biopharmaceutical requires the critical utilization of effective viral clearance steps. As biologic products have inherent risks of potentially carrying and or amplifying adventitious viruses that may be present in or introduced into the original materials, a number of processing steps are needed to provide adequate virus removal. Some common process steps are introduced into downstream purification schemes that provide a physical means to separate and/or remove viruses from the therapeutic protein. The physical steps often include virus-removing filters and chromatographic resins in column or membrane configurations, but can also include the introduction of irradiation, high heat steps, or other means for destroying the infectivity of a virus. Chemical treatment steps are often utilized as a means to inactivate a wide variety of virus types. A general overview is provided that describes the most commonly used techniques for virus removal or inactivation for the validation of virus clearance. Data sets from studies performed at WuXi AppTec for a wide variety of biologics reveal a number of steps that provide guidance for the design of process steps dedicated to viral clearance. The overall efficiency of several process steps reveals a number of efficient, robust steps, such as nanofiltration which can be designed for removal of almost all viral species. Exposure to a low pH or solvent detergent is also a robust step for inactivating enveloped virus. Steps with greater variances in predictability include chromatography steps such as capture columns and anion exchange resins. A lower removal capacity is typically expected for other chromatography steps such as cation exchange steps.

Recent advances in (therapeutic protein) drug development

“…Additionally, as the products are synthesized by cells or organisms, complex purification processes are involved. Furthermore, viral clearance processes such as removal of virus particles by using filters or resins, as well as inactivation steps by using low pH or detergents, are implemented to prevent the serious safety issue of viral contamination of protein drug substances 8 . Given the complexity of therapeutic proteins with respect to their large molecular size, post-translational modifications, and the variety of biological materials involved in their manufacturing process, the ability to enhance particular functional attributes while maintaining product safety and efficacy achieved through protein-engineering strategies is highly desirable.…”

Polysaccharide-based chromatographic adsorbents for virus purification and viral clearance

“…Despite these positive results published some years ago, CEC has been considered to be less robust than AEC for removal of viral contaminants from therapeutic protein preparations [194,204]. AEC robustness has been validated by several studies in which AEC columns were packed with the strong AE resin Q Seph FF [205][206][207][208][209].…”

Non-infectious virus-like particles for the validation of membrane integrity and column performance in bioprocessing

“…In biopharmaceutical manufacture, the expression of therapeutic proteins in host cells will potentially be accompanied by the generation of viral impurities and potential viral contaminants, which are required to be removed or inactivated before formulation (FDA, 1997;Therapeutic Goods Administration, 2009). Ion exchange chromatography (IEC) is an efficient polishing step to remove impurities, including viral contaminants (Falconer et al, 2001;Cipriano et al, 2012). However, multiple re-use of IEC media will involve fouling, molecular build-up, ligand loss or degradation of the matrix support (Levison et al, 1999;Brorson et al, 2003).…”