* Circio has filed an EPO patent application covering a novel genetic element
  that improves the efficiency of circVec-driven circRNA generation by ~4-fold
* This innovation significantly enhances gene expression from AAV-vectors,
  thereby solving a major challenge of conventional gene therapy
* The invention protects critical aspects of the circVec platform and
  strengthens Circio s position as the global leader in circRNA based gene
  expression

Oslo, Norway, 21 May 2026 -- Circio Holding ASA (OSE: CRNA), a biotechnology
company developing novel circular RNA expression technology for gene and cell
therapy, today announces that it has filed a new circVec patent application
with the European Patent Office (EPO), to be expanded with a subsequent global
Patent Cooperation Treaty (PCT) application.

The invention covers critical features required for efficient circular RNA
biogenesis and protein production from DNA and viral vectors. The patent
expands on the existing circVec intellectual property estate and cements
Circio s position as the global leader in circular RNA based gene expression
systems.

"This patent filing is an important milestone in Circio s development and
optimization of the circVec platform technology" said Dr. Thomas B Hansen, CTO
of Circio. "The novel genetic element we have discovered is very effective. To
our knowledge, this has never previously been tested in the context of circRNA
biogenesis. Therefore, this discovery is ideal for patenting to provide strong
intellectual protection of our versatile and powerful circVec platform."

This recent innovation improves intracellular generation of circRNA by
increasing the efficiency of circularization by approximately 4-fold, in
comparison to circVec vectors without the novel element. The specific design
consistently enhances performance and appears to be a critical general design
feature to achieve efficient circRNA-based gene expression from vectors for
both research and therapeutic applications.

Circio has already filed several PCT patent applications covering multiple
aspects of the circVec platform technology. Preclinical in vitro and in vivo
data demonstrate that incorporation of the novel genetic element into circVec,
particularly in the context of AAV gene therapy, substantially increases
circRNA output compared to conventional expression constructs. If granted, the
present application will further extend Circio s intellectual property estate
and provide new coverage with specific relevance for circular RNA-based gene
and cell therapeutics.

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 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.
ties are being conducted by the wholly owned subsidiary\
Circio AB in Stockholm\, Sweden.\