Developing a robust and scalable platform for AAV8 production

Creating robust and scalable bioprocesses is essential for the production of viral vectors, particularly adeno-associated virus (AAV), which are in growing demand for gene therapy applications. This study presents the design and implementation of a scalable AAV8 production platform, leveraging extensive in-house expertise. Three production campaigns were conducted: two at the 2-liter scale and one at the 50-liter scale. The robustness of the upstream and downstream processes was confirmed in the 2-liter campaigns, yielding consistent titers and recoveries close to 80 %. Scalability was validated, demonstrating successful translation from the 2-50 L scale without compromising titers, recoveries, or product quality with a 3-fold enrichment of full capsids. Key modifications, such as adjustments to inoculation concentration, the choice of nuclease, and the direct loading of clarified material onto affinity chromatography, were evaluated to enhance process economics. These modifications did not adversely impact the production process and resulted in significant cost savings. Noteworthy, this study highlights a three-fold enrichment of full capsids, showcasing the process's ability to deliver a higher quality product. While the process is optimized for AAV8, only the polishing step is serotype-specific. The rest of the operations can be broadly applied to other AAV serotypes with minor adjustments. This flexibility suggests potential for wider applications in gene therapy and other fields.