· circVec results demonstrate significantly enhanced protein expression and
durability vs. conventional mRNA-based expression with DNA vectors in vivo
  · CircioŽs R&D strategy is centered on gene therapy, where circVec can deliver
substantial improvement over current gold-standard approaches
  · Circio has selected AAV-based gene therapy for Alpha-1-antitrypsin
deficiency (AATD) as the lead program
  · Circio aims to secure the first circVec partnering deal within twelve months
  · The recent circVec data and a financial update are presented in a company
update webcast available on CircioŽs website

Oslo, Norway 17 April 2024 - Circio Holding ASA (OSE: CRNA), a biotechnology
company developing next generation circular RNA vector technology for gene
therapy, today announces that it has established technical in vivo proof-of
-concept for its proprietary circVec circular RNA platform by demonstrating
statistically significant improvement in durability over mRNA-based expression.
The circVec technology has broad potential, particularly to enhance the potency
and reduce cost of current gold-standard gene therapy, and the R&D strategy is
centered on this rapidly expanding therapeutic area.

"The circVec 2.1 design is performing very well in vitro, and this is now being
translated in vivo with demonstration of enhanced expression level and
durability for circVec 2.1 DNA vectors in mouse models. This provides an
important technical proof-of-concept for CircioŽs technology platform in a real
biological system, which we expect will translate into improved gene therapies
for patients in the future," said Dr. Thomas B Hansen, CTO at Circio. "This new
data indicate that circVec has the potential to outperform current gold-standard
gene therapy approaches, and we are rapidly advancing to design and test circVec
in several AAV and DNA-based therapeutic vector formats."

In parallel to the in vivo characterization, Circio has tested and incorporated
further features into the circVec platform. A dual-function 'remove-&-replace'
concept has been designed and validated in vitro for Alpha-1-antitrypsin
deficiency (AATD), with the ability to both replace functional AAT protein and
remove the disease variant. This genetic disease causes severe symptoms in the
lung and liver, and there are currently no satisfactory therapeutic options
available. AATD represents a major unmet medical need and there are over 200,000
patients affected in the USA and EU.

"Establishing a robust technical in vivo proof-of-concept is a major milestone
for the development of the circVec platform. Based on this validation, Circio
will now explore which targets and diseases represent the best therapeutic and
commercial opportunities," said Dr. Erik Digman Wiklund, CEO at Circio.
"Initially, we have selected AATD as the lead program where our unique 'remove-&
-replace' circVec design has an opportunity to solve two pathological issues in
a single differentiated product. Our aim is to establish in vivo proof-of
-concept in AATD within the next twelve months and select a lead therapeutic
candidate by the middle of next year. We are confident that circVec can be
highly effective in AATD and produce novel gene therapies that outperform
current approaches."

To CircioŽs knowledge, circVec 2.1 far exceeds other known intra-cellular
circRNA-based expression systems, both in terms of circRNA biogenesis efficiency
and protein yield. The platform still has further potential, and Circio is
continuously improving the technology towards circVec 3.0 and beyond. The
platform is protected by deep internal expertise and know-how, with three
patents protecting the core technological features filed to date, and additional
applications in progress.

"Although AATD is CircioŽs lead internal focus, we are continuously exploring
new applications and disease targets to build and broaden our technology
platform and have several ongoing external dialogues to identify opportunities
for future collaborations. Circio is currently working to address specific
questions and requests from these prospective partners and aim to complete our
first business development transaction within the next twelve months," said Dr.
Lubor Gaal, CFO and Head of Business Development at Circio.

The recent circVec data, as well as a financial update and information about the
intended fundraising during Q2 2024, are presented and discussed in a webcast
available via CircioŽs webpage and the Redeye platform link:

Link to webcast - access via Redeye (https://redeye
-3.wistia.com/medias/ghqlfw3t3i)

Circio company update 17 April
PDF.pdf (https://mb.cision.com/Public/17093/3962653/90a924e82debe550.pdf)

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

Lubor Gaal, CFO
Phone: +34 683343811
Email: lubor.gaal@circio.com (erik.wiklund@targovax.com)

About Circio

Building next generation RNA therapeutics

Circio Holding ASA is a biotechnology company developing novel circular RNA gene
therapies and immunotherapy medicines.

Circio has established a unique circular RNA (circRNA) platform for genetic
medicine. The proprietary circVec technology is based on a modular genetic
cassette design for efficient biogenesis of multifunctional circRNA from DNA and
viral vectors, which can be deployed in multiple disease settings. The circVec
platform has demonstrated enhanced and more durable protein expression than
classic mRNA vector systems, and has the potential to become the new gold
-standard for DNA and virus-based therapeutics in the future. The circRNA R&D
activities are being conducted by the wholly owned subsidiary Circio AB based at
the Karolinska Institute in Stockholm, Sweden.

In addition, Circio is developing a cancer vaccine, TG01, targeting KRAS driver
mutations. TG01 is currently being tested in three clinical trials: RAS-mutated
pancreatic cancer and lung and non-resectable pancreatic cancer in US, and
multiple myeloma in Norway. These studies are being run through academic
collaborative networks, supported by prestigious research grants from Innovation
Norway and the Norwegian Research Council, creating read-outs and future
optionality for the program at low cost to Circio.