Regulatory press release

Warrants exercise period commences today – potential proceeds to transform Circio into a clinical-stage circular RNA company

NOT FOR DISTRIBUTION OR RELEASE, IN WHOLE OR IN PART, DIRECTLY OR INDIRECTLY, IN OR INTO THE UNITED STATES OF AMERICA, THE UNITED KINGDOM, AUSTRALIA, CANADA, HONG KONG OR JAPAN, OR ANY OTHER JURISDICTION IN WHICH THE DISTRIBUTION OR RELEASE WOULD BE UNLAWFUL. THIS ANNOUNCEMENT DOES NOT CONSTITUTE AN OFFER OF ANY OF THE SECURITIES DESCRIBED HEREIN.

Oslo, Norway, 26 May 2026 – Circio Holding ASA (OSE: CRNA) (“Circio” or the “Company”), a biotechnology company developing novel circular RNA expression technology for gene and cell therapy, today announces the commencement of the exercise period for the 67,680,945 warrants (Nw.: frittstående tegningsretter) (the "Warrants") listed on the Oslo Stock Exchange under the ticker “CRNAS” (the "Warrant Program"), and the Company's planned use of the potential proceeds. The exercise period commences today, 26 May 2026 at 08:00 CEST to 9 June 2026 at 16:30 CEST, at an exercise price of NOK 8.2508 per warrant (the "Exercise Price").

The exercise period for Circio’s Warrant Program commences today at 08:00 CEST until 16:30 CEST on 9 June 2026, at an exercise price of NOK 8.2508 per Warrant (20% discount to volume weighted average price (VWAP) in the period 8–22 May 2026)
Each Warrant gives the holder a right to subscribe for one new share in the Company at the Exercise Price (the "New Shares")
The potential proceeds from the Warrants Program will be transformative: on top of Circio’s existing cash position, which already provides runway to end of 2030 on a focused preclinical platform strategy, the additional capital will take Circio’s lead circVec-AAV gene therapy program in a genetic heart disease into the clinic
Gross proceeds of NOK 150 million have already been secured through an underwriting agreement entered into by the Company in connection with the Warrant Program, providing certainty of the minimum capital available for the planned use of proceeds
Circio management has committed to exercise warrants for a total of NOK 1.25 million, of which NOK 350,000 by the Company's CEO Dr. Erik D Wiklund
The use of proceeds is structured as a two-step plan: NOK 150 million (already secured) funds a lead program through IND filing in 2H 2028; NOK 300 million extends this plan through Phase 1/2 clinical efficacy data, with runway to the end of 2030.
This development is fundamentally transformative for Circio on a stand-alone basis, taking the Company from a preclinical platform play to a clinical-stage circular RNA leader, and also materially sharpens its profile as a high value, strategic player in the gene and cell therapy field.
A webcast will be held on Thursday 28 May 2026 at 10:00 CEST, with CEO Dr. Erik D Wiklund presenting the Warrant Program, use of proceeds, and highlights from the recent Circio presentations at the American Society of Gene & Cell Therapy Annual Meeting 2026 (ASGCT 2026).

A transformative step – from a fully-funded preclinical platform into the clinic

Following the NOK 250 million private placement in April 2026, Circio has secured a cash runway to the end of 2030 on a focused preclinical platform strategy. This existing capital is being deployed to broaden and accelerate the circVec gene therapy platform across heart, eye and CNS, including completion of the ongoing feasibility study with a top-5 global pharmaceutical company, in vivo efficacy studies in disease models, non-human primate validation, lead candidate selection, and the buildout of in-house in vivo CAR-T cell therapy capability.

On top of this foundation, the potential proceeds from the Warrant Program will accelerate Circio’s lead circVec-AAV gene therapy program in genetic heart disease towards the clinic, through disease model efficacy testing and IND-enabling toxicology studies, targeting IND filing in 2H 2028 and clinical entry in 2029. The funding also supports scale-up of circVec-AAV manufacturing, establishment of a state-of-the-art in vivo CAR-T delivery system, and the buildout of clinical, CMC and corporate teams for the transition into clinical development.

“This is a defining moment for Circio,” said Dr. Erik Digman Wiklund, CEO of Circio. “Our existing cash position already provides runway until the end of 2030 to execute on a broad preclinical circVec platform strategy. The potential proceeds from the Warrant Program will take Circio a fundamental additional step further, accelerating the lead circVec gene therapy program towards IND-filing and turning Circio into a clinical-stage circular RNA company. This expands the value we can build in-house and positions Circio optimally for partnering and strategic discussions in the rapidly evolving circular RNA field.”

NOK 150 million already secured through underwriting agreement for the Warrant Program

To provide certainty around the minimum proceeds from the Warrant Program, Circio has secured gross proceeds of NOK 150 million through an underwriting agreement entered into in connection with the program (the "Underwriting"). The underwriting commitment ensures that Circio can initiate the planned transition to clinical development regardless of the final level of Warrant exercise. The underwriting commitment will be reduced on a NOK for NOK basis from NOK 150,000,000 if Warrants for a gross amount in excess of NOK 150,000,000 are exercised and thus be zero if Warrants are exercised for a gross amount of NOK 300,000,000.

The Underwriting is described further in a separate stock exchange announcement to be published shortly.

In addition to the Underwriting, members of Circio’s management have committed to exercise Warrants and subscribe for new shares for a total amount of NOK 1.25 million, including NOK 350,000 from the Company's CEO Dr. Erik Digman Wiklund.

A two-step use of proceeds plan

The planned use of proceeds is structured in two steps and maintains the end of 2030 cash runway, providing both downside certainty and meaningful upside optionality depending on the final level of Warrant exercise.

The first step (NOK 150 million, fully secured through the underwriting agreement) funds the lead circVec-AAV gene therapy program in a genetic heart disease through IND-enabling pharmacology and toxicology studies, IND filing in 2H 2028 and readiness for clinical entry in 2029, alongside scale-up of circVec-AAV manufacturing, expansion of circVec-AAV testing into novel tissues, establishment of a state-of-the-art in vivo CAR-T delivery system, and buildout of clinical and CMC teams. Additional funding from financing or partnering activities would be required to initiate the clinical study.

The second step (NOK 300 million in aggregate) adds a Phase 1/2 clinical study of the lead circVec-AAV gene therapy program in a genetic heart disease to generate clinical safety and efficacy data. Such clinical data would substantially strengthen and de-risk the circVec platform, and thereby also Circio´s overall position. This funding will include manufacturing of GMP material for clinical studies, validation of the in vivo CAR-T delivery system in primates, and establishment of non-viral delivery to novel cell and tissue types.

Webcast – 28 May 2026 at 10:00 CEST

CEO Dr. Erik Digman Wiklund will host a live webcast in Norwegian on Thursday 28 May 2026 at 10:00 CEST, summarizing Circio’s ASGCT 2026 presentations and the Warrant Program. Registration details are available on the Circio website.

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.

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This announcement is not and does not constitute an offer of securities for sale or a solicitation of an offer to purchase securities of the Company in the United States or any other jurisdiction. Copies of this document may not be sent to jurisdictions, or distributed in or sent from jurisdictions, in which this is barred or prohibited by law. The securities of the Company may not be offered or sold in the United States absent registration or an exemption from registration under the U.S. Securities Act of 1933, as amended (the "U.S. Securities Act").

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