Recombinant AAV Production Platforms: Comparative insights for gene therapy manufacturing

Recombinant adeno-associated virus (rAAV) has emerged as a leading platform for gene therapy, leveraging both naturally occurring and engineered capsids to deliver therapeutic transgenes. As clinical and research demand for rAAV has grown, vector quality and manufacturing consistency have become critical considerations. Two production platforms account for the vast majority of clinically relevant rAAV supply: the human embryonic kidney cell line (HEK-293) and the Spodoptera frugiperda (Sf9) insect cell line paired with baculovirus expression vectors. The platforms differ in empty-to-full capsid ratios and process impurities, including encapsidation of host-cell and plasmid DNA. While Sf9 offers advantages in yield, scalability, and manufacturing economics, engineering appropriate capsid protein stoichiometries within the baculovirus system remains a challenge. This review examines these and other key features of each platform as they relate to vector quality and clinical suitability.

What you will learn

01

How the HEK-293 and Sf9/baculovirus platforms differ in upstream design, from helper function delivery and plasmid consolidation to the translational engineering needed to achieve correct Rep and VP1:VP2:VP3 stoichiometry

02

Why downstream purification trains are largely parallel across both platforms, and how lysis, clarification, immunoaffinity capture, and AEX-based enrichment of full capsids determine recovery and empty-to-full ratios

03

How vector genome integrity, capsid composition, and certificates of analysis underpin meaningful platform comparisons—and why reported potency differences often reflect preparation quality rather than the production system itself

Key interests

rAAV manufacturing

HEK-293

Sf9/baculovirus

Capsid stoichiometry

Empty:full ratio

Downstream processing

Vector genome integrity

Critical quality attributes