Amsterdam & Oegstgeest, The Netherlands, October 1, 2026 – Annogen, a leader in making gene therapies safer and more effective through advanced gene expression engineering, today announced a collaboration with Genewity, a clinical-stage gene therapy company dedicated to developing durable, one-time treatments for children with severe genetic diseases. Together, the two companies will work to identify and validate promoters precisely matched to the requirements of Genewity's therapeutic programs, thereby ensuring that the gene therapies that Genewity develops are built on the strongest possible biological foundations and safety requirements.
The difference a promoter makes
For families whose children are born with severe genetic diseases, the promise of gene therapy is profound: a single treatment, using the child's own cells, that corrects the underlying defect.
Turning that promise into a reliable, durable therapy depends on every component working as intended in the actual biological environment of the patient. A critical component of this is the promoter, the regulatory sequence that determines whether a therapeutic gene is expressed at the right level, in the right cells and consistently over time.
Working with a suboptimal promoter can mean insufficient therapeutic effect and can even lead to safety issues. Therefore, choosing the best promoter, i.e. one that has been rigorously validated to drive the required level of expression, while resilient to silencing and does not lead to safety issues, is one of the most consequential decisions in the design of a gene therapy. It is precisely here that Annogen's expertise makes a difference.
Validated expression in the cells that matter
Annogen's strategy is different from typical offerings which will often rely on public data to make computational predictions, which then need to be validated by the customer. Instead, Annogen goes through iterations of designing and testing, starting from large-scale public and proprietary SuRE™ datasets, and ending with validations in the relevant cell types. Importantly, this screening can be performed in the exact cell types a therapy will ultimately need to work in, including in vivo and cell states for which no prior reference data exists. The result is a promoter that not merely works in theory but instead is proven to work in the specific biological context that matters.
For Genewity's programs, this means generating direct functional evidence of which promoters drive strong, stable expression in primary blood cells under conditions relevant to clinical use, in the cells that will ultimately be returned to patients.
A shared commitment to children who cannot wait
Genewity's mission is to develop therapies that address the root cause of severe genetic diseases in children, in a single treatment. That ambition demands that every component of a therapy will be selected with the rigor and care that the patients and families deserve.
Annogen exists to bring that standard to gene expression engineering. By ensuring that the promoters powering a therapeutic gene have been functionally validated in the precise biological context they will encounter in a patient, Annogen helps its partners build cell and gene therapies that are safer, more effective, and better equipped to deliver on their clinical promise.
"We are proud to support Genewity's mission to bring durable, transformative treatments to children with severe genetic diseases," said Dr. Jorisvan Arensbergen, CEO and founder of Annogen. "The work we do together on transgene expression is not an ancillary consideration, but it is central to whether a therapy works as intended, safely and durably, in the patients who need it most. That is what drives us."
About Annogen
Annogen B.V. is an independent, Amsterdam-based biotechnology company making gene expression truly programmable. At Annogen, we are making promoter design a highly effective and precis eengineering discipline grounded in large-scale in-vivo datasets, enabling novel therapies that are safer and more effective. Annogen supports leading biopharmacompanies with bespoke promoter design, some driving clinical-stage programs, and in addition develops proprietary off-the-shelf promoters. We are a team of 10+ people combining deep scientific expertise with a pragmatic, collaborative approach to deliver solutions with real-world impact. For more information, visit www.annogen.bio.
About Genewity
Genewity is a clinical-stage biotechnology company based in the Netherlands, developing one-time gene therapies for life-threatening rare pediatric diseases. Our ex vivo lentiviral gene therapy approach uses a patient’s own bone marrow stem cells, which are genetically modified outside the body to address the underlying genetic defect, and then returned to the patient. Genewity is based at the Leiden Bio Science Park in the Netherlands. For more information, visit www.genewity.tech.
Contact Annogen: Dr. Martijn Kelder, Chief Strategy Officer, info@annogen.bio
Contact Genewity: Dr. Arno Bisschop, Chief Executive Officer, info@genewity.tech
