Application Note - Innovative Medicine Manufacturing

Challenge

Process development is under constant time pressure. With the help of platform approaches, efforts are ongoing to reduce the number of factors influencing a process to bring a finished product to the pharmaceutical market more quickly. The more familiar you are with the process, the easier it is to identify influencing factors and evaluate the cells' response to derive the highest-yield production strategy.

Impedance spectroscopy not only shows the viable cell volume but also provides information on intracellular conductivity and cell size distribution, which is valuable for understanding the cells' response to process control. When combined with real-time CO2 measurements, challenges such as CO2 accumulation from 500 L at the bottom of the reactor are observed at a new level.

Results

Process control in the small reactor is relatively easy to implement. Even here, the aim is to follow simple protocols that can then be scaled to production. In most cases, viability and viable cell density are indicators of a successful process. How active a cell is, or what osmotic state it is in, is often ignored because this cannot be observed in offline samples. The data from KBI Biopharma shows an increasing trend in permittivity, which represents the living biovolume. The cells are induced by a temperature shift, and the conductivity trend indicates the feeding points (graph B).

Changing trends in alpha and fc indicate the lag phase for the first 45 hours. Thereafter, the fc trend indicates the cells' response to the feed. The current theory is that the cells use their ion channels to adapt to the new conditions. Towards the end of the process, the cells' development into an apoptotic state can be observed in the alpha trend (graph C).

Conclusion

• Changes in the cell at the intracellular level and in the cell size distribution offer opportunities for process development and for production.
• New approach such as changing the feeding strategy with different time, volume, concentration, and feed media can enhance/improve: change of the feeding strategy with different time, volume, concentration and feed media.

Potential improvements:

Shortening time to market by implementing feeding strategies that enable higher yields in less time can improve process productivity.