* AAV-circVec 3.2 achieves 40-fold enhanced protein expression in heart vs.
conventional mRNA-based AAV gene delivery
* Results are highly statistically significant and have been confirmed both by
longitudinal live imaging and ex vivo tissue analyses
* Similar results from ongoing experiments targeting other tissues with
different AAV variants support broad applicability of the circVec technology
as a novel platform to transform gene therapy
* Circio has selected Danon disease as the initial cardiac indication to
validate the AAV-circVec technology in a therapeutic setting
Oslo, Norway 8 October 2025 -- Circio Holding ASA (OSE: CRNA), a biotechnology
company developing powerful circular RNA technology for next generation
nucleic acid medicine, today announces the publication of a comprehensive data
package demonstrating AAV-circVec in vivo tissue-specific proof-of-concept.
The results are being delivered in a poster presentation at the European
Society of Cell and Gene Therapy (ESGCT) annual meeting 2025 in Seville,
Spain.
In the ESGCT poster presentation, Circio is presenting new and expanded in
vivo results demonstrating the advantage of circVec as a novel expression
system to transform AAV gene therapy. In heart tissue, circVec 3.2 shows
highly localized activity that outperforms conventional mRNA-based AAV
expression by up to 40-fold. These results have been demonstrated and
confirmed both by IVIS scanning and post-mortem ex vivo tissue analysis. To
validate the technology in a therapeutically relevant setting, Circio has
initiated technical development of circVec-AAV gene therapy constructs for
Danon disease, a devastating cardiac genetic disease with no therapeutic
options available today.
"Circio has worked systematically to optimize the circVec design for AAV gene
delivery over the past two years. The latest circVec 3.2 generation
incorporates a novel genetic feature that drives up AAV protein expression to
levels that substantially exceed conventional mRNA-based AAVs. We are now
advancing rapidly to validate these findings in relevant genetic disease
models," said Dr. Thomas B. Hansen, CTO of Circio. "Importantly, the strong
advantage in the heart is also observed in several other tissues and AAV
variants. This consistency supports broad applicability of our circVec
platform, thereby opening development and partnering opportunities in multiple
therapeutic areas."
The presentation also includes data showing a strong increase in expression
levels with the trend for continued signal accumulation following local
delivery of previous generation circVec 2.0 AAV vector to the eye. Testing of
the latest generation circVec 3.2 in eye and other tissues is currently being
initiated, and a novel circVec generation 4.0, which incorporates further
genetic enhancer elements, is due to enter initial in vivo screening
experiments.
"ESGCT provides an excellent forum to showcase the circVec platform to a wide
academic and industry audience as a potential solution to address the key
issue preventing broad adoption and success of AAV gene therapy," said Dr.
Erik D Wiklund, CEO of Circio. "The AAV field has recently experienced several
major setbacks due to severe toxicity issues in ongoing clinical studies.
Switching to circVec-based expression can enable substantial dose reduction,
which we expect will lead to considerable improvements in safety for patients
and lower treatment cost. The circVec platform could thereby completely
transform the clinical and commercial viability of AAV therapy as we know it
today and establish circVec as a novel gold-standard gene expression system."
Title of presentation and poster:
CircVec: Enhancing gene and cell therapy using circular RNA vector expression
technology (poster no. 1041)
Presenter: CTO Dr. Thomas B Hansen & CSO Dr. Victor Levitsky
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 powerful circular RNA
vector expression technology for next generation nucleic acid medicine.
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 2025-10-08 07:00
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.