Circio and Tcelltech jointly announce CAR-T cell therapy research collaboration

* The collaboration will combine Circio's circVec and Tcelltech's nanoSMAR technologies to generate next-generation in vivo CAR-T and TCR-T cells with enhanced and more durable expression * The collaboration is part of Circio s strategy to test circVec across multiple modalities and delivery technologies to create novel highly differentiated in vivo CAR-T therapies

Oslo, Norway, and Mannheim, Germany 24 June 2026 -- Circio Holding ASA (OSE: CRNA), a biotechnology company developing novel circular RNA expression technology for gene and cell therapy, and Tcelltech GmbH, a biotechnology company developing non-viral, episomal DNA vector technology for the engineering of T cells, today jointly announce a research collaboration to combine Circio s circVec circular RNA expression technology with Tcelltech s double-stranded, non-integrating nanoSMAR vector platform for the development of next generation engineered T-cell therapies.

Engineered T-cell therapies such as CAR-T have transformed the treatment of certain cancers. However, ex vivo manufacturing remains complex and the shift towards in vivo approaches currently relies on viral vectors that have significant safety concerns. By integrating the technologies developed by Circio and Tcelltech, the parties aim to engineer T-cells with enhanced and sustained CAR/TCR expression, without the need for viral vectors. The aim is to develop novel in vivo cell therapies that are safer and more durable than current in vivo approaches.

"The combination of Tcelltech's non-viral, episomal nanoSMAR DNA vector platform with Circio's circVec expression technology holds great promise for the development of in vivo gene delivery systems that are non-disruptive to target cells, maintain high expression levels, and enable straightforward, cost-effective manufacturing. Furthermore, the exceptionally large cargo capacity of nanoSMAR vectors---beyond what is achievable with viral approaches---enables the design of complex, and sophisticated constructs incorporating multiple payload genes and regulatory elements," said Dr. Richard Harbottle, Head of Vector Technology and Manufacturing at Tcelltech.

Under the collaboration, Circio and Tcelltech will combine Circio's circVec circular RNA expression technology with Tcelltech's non-viral, high-cargo capacity nanoSMAR vector platform and evaluate the combination in engineered T cells through a staged research program. An initial proof-of-concept phase will compare how strongly and how durably the different technology combinations drive gene expression in primary human T cells, followed by a functional phase in which CD19-directed CAR T cells are generated and tested for their ability to kill tumor cells.

"In vivo T cell therapy is one of the most exciting frontiers for our circVec technology and is a rapidly advancing approach that could make these therapies more scalable and accessible," said Dr. Victor Levitsky, Chief Scientific Officer of Circio. "Tcelltech s universal nanoSMAR platform is a promising and differentiated delivery technology for T-cells, which we expect will act synergistically with circVec-enhanced payload expression. This collaboration fits into Circio s broad business development strategy of testing circVec across multiple modalities and delivery systems to identify the optimal technology combination and identify the most promising therapeutic avenues."

About Tcelltech Tcelltech GmbH - founded by a team of clinicians and scientists from the German Cancer Research Center DKFZ - has developed technology platforms, nanoSMAR and selecTCR, which can overcome some of the fundamental challenges and limitations, like manufacturing complexity and cost or suitable target identification and targeting moiety generation, currently prohibiting the success of immunotherapies for a larger number of patients. A clinical study targeting glioblastoma with a TCR cell therapy manufactured ex vivo with a nanoSMAR-based DNA vector is planned in 2026. We are working towards in vivo cell therapies and believe that our platforms will significantly improve immunotherapies for cancer and other diseases.

About Circio Circio Holding ASA is a biotechnology company developing novel circular RNA expression technology for gene and cell therapy.

Circio has established a unique circular RNA (circRNA) vector expression technology for next generation RNA, DNA and viral therapeutics. The proprietary circVec platform is based on a modular genetic construct designed for efficient biogenesis of multifunctional circRNA inside target cells. The circVec platform has applications in multiple therapeutic settings, including genetic medicine, cell therapy and chronic disease. It has demonstrated 75-fold increased RNA half-life and up to 50-fold enhanced protein expression vs conventional mRNA-based viral and non-viral vector systems, with the potential to become a new gold-standard gene expression technology. The circVec R&D activities are being conducted by the wholly owned subsidiary Circio AB in Stockholm, Sweden.

For further information, please contact: Erik Digman Wiklund, CEO Phone: +47 413 33 536 Email: erik.wiklund@circio.com

Lubor Gaal, CFO Phone: +34 683 34 3811 Email: lubor.gaal@circio.com