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Prof. Dr. Kurt Eyer is co-author of a groundbreaking essay

Pharmaceutical planner Prof Dr Kurt Eyer is co-author of a groundbreaking essay

We are proud to call some of the most talented scientists and engineers in the pharmaceutical industry “our colleagues”. One of them is Prof. Dr. Kurt Eyer, Lead Engineer – Process Bio at Pharmaplan Switzerland, who recently co-authored a scientific essay that was published in the journal Biotechnology and Bioengineering (Wiley-Verlag 2020). Increasing cleaning performance is a ubiquitous topic in pharmaceutical downstream processes. A new direction to improve purification processes is shown in Kurt’s paper.


His article shows that affinity chromatography (protein A step) is a critical step in host cell protein (HCP) clearance -Contaminations in purification processes with monoclonal antibodies (mAb). Although this is one of the most effective purification steps, different concentrations of protein contaminants are often observed in the eluate.
The results show that optimization of the mAb purification process using Protein A as the primary capture step depends primarily on being able to effectively deplete DNA and associated complexes early in the process rather than trying to incorporate HCP reduction directly at the harvest step. These results could be confirmed with three different therapeutic mAbs expressed by the same CHO (Chinese Hamster Ovary) cell line.
Removing more contaminants early in the process ultimately results in the protection of the chromatography columns an increased purification performance.

This simplifies the process by removing multiple types of contaminants in a single process step, resulting in better process economics. Future processes could be simplified, e.g. by reducing the size of the chromatography columns, significantly reducing the filter surface area for sterilization filters and fewer polishing steps. Of course, this still has to be proven with other cell lines and for other processes, but the experiments have shown a new possibility for process intensification.
Congratulations to Kurt on your outstanding publication, which has great potential, pharmaceutical mAb production and its process intensification to change in the future! We’re proud to have you on board!
To read the full article, please visit:

Source: Van de Velde J, Saller MJ, Eyer K, Voloshin A. Chromatographic clarification overcomes chromatin‐mediated hitch‐hiking interactions on Protein A capture column. Biotechnology and Bioengineering. 2020;1-9.