Berlin, Germany ̶ May 27, 2026
ProBioGen today announced the launch of AGE1.CR.ReX®, its next-generation avian designer cell line for stable, high-titer poxvirus production and rapid generation of recombinant modified vaccinia Ankara (MVA). Enabled for switchable gene expression and the proprietary TetherexX™ System, the new platform is designed to accelerate and simplify the development of modern poxvirus-based vaccines and oncolytic viruses while improving genetic stability and manufacturing reliability.
Built on ProBioGen’s proven GMP AGE1.CR.pIX® lineage, AGE1.CR.ReX has been engineered to enable inducible control of transgene expression during virus production. This eliminates selection pressure against difficult or unstable transgenes, a common challenge in poxvirus vector development that can otherwise result in reduced viral titers, inconsistent batch performance, and repeated plaque purification cycles.
The AGE1.CR.ReX host cell line directly addresses these issues by enabling more stable recombinant MVA generation with higher productivity and increased process robustness. As a result, developers can achieve production-ready virus candidates faster and with greater confidence. Central to this is the TetherexX System, ProBioGen’s proprietary approach for rapid generation and rescue of pure recombinant MVA. Tetherin, a cellular factor of the innate immune system, is used here as a novel selection marker to selectively eliminate parental viruses, reducing the need for operator-intensive purification steps and supporting a more reliable path toward production-ready virus candidates.
Combined with the TetherexX System, the AGE1.CR.ReX platform offers several advantages:
The TetherexX system together with the AGE1.CR.ReX cell line build the foundation for ProBioGen’s/Minapharm’s recent initiative towards an African Bundibugyo Ebola virus (BDBV) vaccine. In addition, AGE1.CR.ReX is designed for applications where conventional systems may fail to deliver both transgene stability and high viral titers and is also well suited in the development of oncolytic viruses, personalized medicines, and for supporting pandemic preparedness programs.
"In developing AGE1.CR.ReX, we focused on solving one of the bottlenecks that may impact recombinant poxvirus generation: maintaining stable transgene expression without compromising yields," said Dr. Ingo Jordan, Vice President Vaccine Strategies at ProBioGen. "The combination of inducible transgene control and the TetherexX System enables faster development timelines and more robust industrial manufacturing workflows for vaccine and viral vector developers."
"AGE1.CR.ReX and TetherexX are essential innovations for epidemic preparedness. They open the door for MVA as one of the rapid response vaccine platforms," explained Dr. Volker Sandig, Chief Scientific Officer at ProBioGen. "Without these technologies accelerated development and reliable manufacture of an MVA-based BDBV vaccine would not be possible."
AGE1.CR.ReX is fully developed and GMP-banked at ProBioGen and is available with full technology transfer and integrated GMP manufacturing support.
About ProBioGen
ProBioGen is a Berlin-based expert in the development and manufacturing of biopharmaceuticals, viral vectors, and vaccines, powered by proprietary technologies that enhance product quality and features. It has developed multiple innovative vaccine platforms, including Lenti.RiGHT®, AGE1 host cell lines and the IP-protected MVA-CR19 strain, which has a unique genomic signature. Operating for over 30 years, ProBioGen runs three manufacturing lines in Berlin, where 300 employees contribute to advancing next-generation therapies and global biotech innovation.
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