Scalable downstream process development for in vivo gene therapy products: understanding full/empty separation capabilities and challenges with ion exchange chromatography

Abstract

Adeno-associated viruses (AAVs) for in vivo gene therapy are a dominant viral vector platform in the gene therapy landscape. A key challenge in viral vector manufacturing, particularly with AAVs, is effective and consistent separation of full particles (i.e. viral vector capsids containing the full recombinant cDNA of the gene of interest) from empty capsids. Monolith-based ion exchange chromatography (IEX) is a promising tool to achieve this separation but poses challenges with consistency upon scale-up. This paper outlines some of the scale-up challenges and potential mitigations to achieve consistent separation of full and empty particles. IEX is evolving to become the industry standard for downstream separations as industrialization of gene therapy manufacturing continues.