Purification of enveloped viruses and virus-like particles poses several challenges due to their large size and complexity. Here we describe the development, scaling, and implementation of a single step method for the purification of a retrovirus-like particle. Specifically, we describe the processes of purification media screening, buffer system development, column scaling, cGMP process streamlining and optimizing. Presented in this case study, purification media screening and initial buffer system development were performed using 19 mL of bioreactor feed stream and 1.0 mL columns. Additional process development on 1.0 mL columns included the introduction of a pre-column nuclease digest and increasing the feedstream to column volume ratio of 19:1 to 60:1. Column scaling was performed in 4 steps. First, column length was increased from 2.0 cm to 20.0 cm. Next, column diameter was increased from 0.8 cm to 2.6 cm to 6.2 cm, and finally to 17.8 cm. In aggregate, process scale was increased from 19 mL to 275 L, or approximately 14,000-fold. Concurrent with column scaling, the nuclease digest, and buffer system was further optimized to reduce enzyme and buffer consumption, increase column life, and reduce process time. The resulting cGMP unit operation required approximately three hours to process 275 liters of nuclease treated feedstream and was used to produce material for clinical trials.

Downstream process development for a clinical stage retrovirus-like particle

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.