Circio presents groundbreaking in vivo data showing up to 50-fold enhanced circVec-AAV gene expression in eye

26 Feb 2026 07:00 CET

* New data in eye: New in vivo results show that AAV-circVec 4.0 outperforms
conventional mRNA-based AAV expression by up to 50-fold following local
delivery to eye
* Validation in heart: Previously reported 40-fold enhanced gene expression in
heart has been further validated and extended, confirming the potential of
the AAV-circVec approach in cardiac disease
* Successful fundraising: NOK 68.6 million (approx. USD 7 million) was raised
in a 50% oversubscribed financing transaction to support broadened and
accelerated development of the circVec platform

Oslo, Norway, 26 February 2026 -- Circio Holding ASA (OSE: CRNA), a
biotechnology company developing novel circular RNA expression technology for
gene and cell therapy, today announces it is presenting new and confirmatory
in vivo data for its circVec-AAV expression platform. The in vivo results
show, for the first time, up to 50-fold enhanced AAV-circVec expression in the
eye compared to conventional mRNA-based AAVs. These results open ophthalmology
as a promising avenue for development of circVec based gene therapy.

Circio management will provide an overview of the new circVec results and a
financial update in a live webcast at 10:00am CET, today, 26 February 2026.
CTO Dr. Thomas B Hansen will present a summary of recently completed
experiments testing AAV gene therapy enhanced by the latest generation 3.2 and
4.0 designs of Circio's circular-RNA expression platform circVec in heart and
eye.

Local delivery of AAV-circVec 4.0 to the eye achieves the strongest
improvement vs. mRNA-based AAV to date, with up to 50-fold increased gene
expression observed in vivo. Importantly, the data also demonstrate that
AAV-circVec still can outperform a conventional AAV by 10-fold when delivered
at a 90% reduced dose level.

Increasing industry interest is one of the reasons Circio has selected eye
disease (ophtamology) as another area of development, as evidenced by several
recent strategic transactions by major pharma companies and specialist
investors. The circVec platform offers a novel circular RNA-based gene
expression system that has the potential to substantially increase the
potency, reduce toxicity and lower cost for AAV-based therapeutics targeting
genetic and degenerative eye diseases with high unmet medical need.

In parallel, Circio has continued to build the AAV-circVec 3.2/4.0 data
package in heart. The previously reported 40-fold gene expression increase has
been reproduced in new experiments, and molecular analyses of ex vivo tissue
samples demonstrate that 80% of heart cells are positive for circVec
expression following systemic AAV delivery at low doses. Moreover, RNA and AAV
DNA copy number quantification confirm, as expected, that the circVec
expression advantage is directly caused by the increased durability of
circular RNA vs. mRNA, which validates the main scientific rationale
underpinning the circVec platform.

"Circio is undertaking broad characterization and optimization of the circVec
technology, and the strong AAV gene expression performance in heart has now
been exceeded by in vivo data in eye," said Dr. Thomas B Hansen, CTO of
Circio. "The expanding data package clearly demonstrates the potential of the
circVec platform to improve efficacy, safety, and accessibility of AAV gene
therapy. Next, our focus will be to apply these promising technical findings
in disease-relevant contexts, with the aim to develop therapeutic AAV-circVec
constructs to treat heart and eye disease with high unmet medical needs."

Earlier in Q1 2026, Circio completed a financing, first announced in December
2025, raising a total of NOK 68.6 million (approx. USD 7 million) in a 50%
oversubscribed rights issue and parallel private placements. The transactions
will provide Circio with the required capital to accelerate circVec R&D
activities over the next twelve months. An associated warrant structure with
exercise in June 2026 can bring in additional capital and extend the financing
runway well into the second half of 2027.

"The robust technological foundation, unique expertise and strong in vivo
data, combined with the recently announced R&D collaboration with a global
pharma company, were key elements to achieve a highly successful fundraising,"
said Dr. Erik Digman Wiklund, CEO of Circio. "With strong support from
existing shareholders, we were able to raise substantially more funds than
originally targeted. The capital infusion will enable Circio to expand the R&D
team in Stockholm, accelerate circVec platform development and deliver
important scientific milestones to generate new business development
opportunities and support Circio s continued growth."

Presenters:
CEO Dr. Erik Digman Wiklund
CTO Dr. Thomas Birkballe Hansen

Time: 10:00 CET on Thursday 26 February 2026

Click here to access Teams webcast
(https://teams.microsoft.com/meet/31333387615034?p=2AsTUx1434hLnCr0FC)
Meeting ID: 313 333 876 150 34
Passcode: 8SA24KF2

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

Neil Hunter -- Hunter PR
Phone: +44 782 125 5568
Email: neiljameshunter@gmail.com

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 40-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 article 17 and section 5-12 of the Norwegian Securities
Trading Act. The information was submitted for publication at 2026-02-26 07:00
CET.

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.

More information:
Access the news on Oslo Bors NewsWeb site

666862_260226 1Q26 Webcast.pdf