ProteoGenix Launches New XtenCHOTM Transient CHO Expression System to Improve Biologics Development

March 15, 2022

XtenCHO - new ultra-high yield transient expression system

New CHO system offers ten times higher yields, optimised plasmid stability and smart protocols with less hands-on time

Schiltigheim, France – ProteoGenix, a contract research organization specialized in biologics discovery and bioproduction, announces the launch of its XtenCHOTM Transient Expression System. Due to its enhanced plasmid stability and optimized metabolism, the new proprietary mammalian cell-based expression host achieves up to ten times higher yields with less hands-on time compared to existing solutions. The new CHO host aims to simplify recombinant protein production and accelerate early phase drug screening.

XtenCHOTM was developed by ProteoGenix from the parental cell line CHO-K1 by engineering its genome to exhibit properties that ultimately maximize protein production yields. Compared to other commercially available CHO systems, the new cell line has enhanced robustness, recovering quickly after thawing and performing well even in suboptimal conditions.

Its ultra-high yields result from the concerted effect of using an optimized animal component-free growth medium, one-step highly efficient transfection reagent, and ultra-high expression vector. These components work together to reduce premature plasmid loss and create a three to ten-fold increase in transient gene expression (TGE) yields in comparison to market-leading CHO systems.

The new host has been used and optimized by ProteoGenix’s experts for the past 5 years to produce over 3500 recombinant proteins. These have included antibodies from multiple species, isotopes and formats, such as bispecific antibodies, ADCs and nanobodies. In addition, a large number of non-antibody proteins have been produced, including highly functional enzymes, membrane-bound receptors, cytokines, interleukins and transcription factors.

As part of its mission to support research labs around the world, ProteoGenix has launched its XtenCHOTM Transient Expression System Kit for widespread use within the life science research community. This follows extensive testing and optimization by the ProteoGenix team. With the ability to perform superior protein folding and human-like post-translational modifications, XtenCHOTM has proven to be ideal for the small and medium-scale production of monoclonal antibodies.

“The new XtenCHOTM system produces monoclonal antibodies that are indistinguishable from biopharmaceutical-grade biologics produced in stable systems. This eases process scalability and reduces the risks when transitioning from the bench to the clinic,” said Dr. Raphaël Hopfner, CSO and co-founder of ProteoGenix.

“We have launched XtenCHOTM to help speed up the process of early drug development; making it safer, more flexible, accessible and easier to integrate into existing biologics discovery workflows using cost-effective reagents to achieve very high yields,” added Philippe Funfrock, CEO and co-founder of ProteoGenix.

XtenCHOTM Transient Expression System is for Research Use Only. For more information, click here.

About ProteoGenix – ProteoGenix is a France-based biotech contract research organization (CRO) providing flexible end-to-end solutions for the discovery and development of life-saving biologics, precision diagnostic tools, and high-quality reagents for research. As a global leader in antibody, protein, peptide, and gene production, ProteoGenix aims at fostering the development of next-generation immunotherapies by focusing on developability. For more information, please visit

For further information, please contact:

Clément Aubin
Product Manager
T: +33 (0)390 20 54 70