(485b) Mechanistic Modeling to Enhance Production of Recombinant Adeno-Associated Virus with Insect Cells

The demand of recombinant adeno-associated virus (rAAV) for gene therapies is forecast to soon outreach the current production capacity, considering the growing number of approved products and of pre-clinical and clinical stage trials.^1,2 Current rAAV manufacturing processes have less-than-desired yields and produce a significant amount of empty capsids.^3,5 Recently, FDA approved the first rAAV-based gene therapy product manufactured in the invertebrate Sf9 cell line derived from Spodoptera frugiperda with the baculovirus expression vector system (BEVS).^4,6,7 The BEVS technology demonstrated scalable production of high rAAV volumetric titers that provide a substantial economy of scale in reducing cost-of-goods.^8,9 In this work, a mechanistic model is developed to describe the key extracellular and intracellular phenomena occurring during baculovirus infection and rAAV virion maturation in the Sf9 cells. The predictions of the model show good agreement with several experimental datasets on rAAV manufacturing in Sf9 cells using BEVS. A model-based analysis of the process is carried out to provide insights on potential bottlenecks that limit the formation of full capsids. The analysis suggests process as well as genetic modifications that can enhance rAAV productivity.

References

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9. Joshi, P.R.H., Cervera, L., Ahmed, I., Kondratov, O., Zolotukhin, S., Schrag, J., Chahal, P.S., and Kamen, A.A. (2019). Achieving high-yield production of functional aav5 gene delivery vectors via fedbatch in an insect cell-one baculovirus system. Mol Ther Methods Clin Dev 13, 279–289.