· Seven patients were enrolled in the safety cohort with follow-up for three
months
  · TG01 was well tolerated, and no safety concerns were reported
  · The study is now open for full enrollment

Oslo, Norway, 7 December 2023 - Circio Holding ASA (OSE: CRNA), a biotechnology
company developing novel circular RNA and immunotherapy medicines, today
announces that mutant RAS cancer vaccine TG01 adjuvanted by QS-21 STIMULON has
passed the planned safety cohort review without any concerns in the multiple
myeloma trial at Oslo University Hospital (OUS). The study has now opened for
full enrollment of twenty patients in total.

Ola Melin, TG program lead of Circio Holding ASA, said: "This is the first time
TG01 has been given to multiple myeloma patients, and the first formal safety
review of TG01 administration with QS-21 STIMULON as adjuvant. As expected,
there were no safety concerns reported, and we are very pleased that the study
can now continue as planned. Dr. Schjesvold and his team have been very
efficient to achieve this milestone rapidly, and we expect that the study will
be fully enrolled during 2024."

In this phase 1 clinical trial, TG01 is being tested as a monotherapy in
multiple myeloma in a clinical collaboration between OUS and Circio. The study
is led by multiple myeloma expert Dr. Fredrik Schjesvold with OUS as the study
sponsor. Circio provides TG01 drug supply, scientific support and a financial
contribution.

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

Renate Birkeli, Investor Relations
Phone: +47 922 61 624
Email: renate.birkeli@circio.com (renate.birkeli@targovax.com)

About Circio

Building next generation RNA therapeutics

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

Circio has established a unique circular RNA (circRNA) platform to develop novel
circRNA medicines for rare disease, vaccines, and cancer. 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 for many purposes. 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 two clinical trials in RAS-mutated
pancreatic cancer and multiple myeloma in the USA and 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.