Integrated continuous processing of proteins expressed as inclusion bodies: GCSF as a case study

Area of Science:

• Biopharmaceutical Manufacturing
• Chemical Engineering
• Biotechnology

Background:

• Biopharmaceutical affordability remains a significant challenge, especially in developing nations.
• Integrated continuous manufacturing platforms offer enhanced productivity and economics for biopharmaceutical production.
• Continuous manufacturing processes for bacterial proteins are less developed compared to monoclonal antibodies.

Purpose of the Study:

• To develop an end-to-end integrated continuous downstream process for therapeutic proteins expressed in Escherichia coli inclusion bodies.
• To demonstrate the capability and consistency of the developed continuous bioprocessing train.
• To highlight complexities in process integration for continuous biomanufacturing.

Main Methods:

• An integrated continuous downstream process was designed, starting from inclusion bodies to unformulated drug substance.
• The process involved continuous refolding in a coiled flow inverter reactor.
• Downstream processing utilized three-column periodic counter-current chromatography for capture and three-column con-current chromatography for polishing.

Main Results:

• The continuous bioprocessing train operated uninterrupted for 26 hours.
• Product purity exceeded 99%, with high molecular weight impurities below 0.5%.
• Host cell proteins were below 100 ppm, and host cell DNA was below 10 ppb, with consistent quality attributes.

Conclusions:

• The developed integrated continuous downstream process offers a smaller facility footprint, higher productivity, and improved equipment/resin utilization.
• This approach addresses the need for more efficient and universal continuous manufacturing platforms for biotherapeutics.
• The study promotes advancements in continuous bioprocessing for bacterial protein therapeutics.