Circio announces that the ongoing feasibility study with a major global pharmaceutical corporation is progressing to in vivo testing

April 24, 2026
Press release - Regulatory

Oslo, Norway, 24 April 2026 – Circio Holding ASA (OSE: CRNA), a biotechnology company developing novel circular RNA expression technology for gene and cell therapy, today announces that the previously reported feasibility study with one of the major global pharmaceutical corporations is progressing to the next phase of testing.

Reference is made to the stock exchange notice by Circio on 18 November 2025, announcing a feasibility study with a major global pharmaceutical company. The project involves testing of Circio’s circVec circular RNA expression technology for delivery with AAV vectors in a specific therapeutic area. Initial technical testing in vitro has now been successfully completed, and certain circVec candidates have been selected for further testing in vivo. The project is performed by Circio and is fully funded by the pharmaceutical company. The agreement does not include any downstream rights or obligations on either party.

About Circio
Building circular RNA expression systems for enhanced gene and cell therapies

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.

This information is considered to be inside information pursuant to the EU Market Abuse Regulation (MAR) and is subject to the disclosure requirements pursuant to MAR and section 5-12 of the Norwegian Securities Trading Act. The information was submitted for publication at 2026-04-24 22:00 CEST.

This stock exchange announcement was published by Mats Hermansen, VP Finance, on behalf of the Company, at the time and date stated above in this announcement.