Leqembi Iqlik® for initiation treatment launched in the US

Stockholm, Sweden, August 24, 2026 – BioArctic AB's (publ) (Nasdaq Stockholm: BIOA B) partner Eisai today announced that lecanemab-irmb subcutaneous injection (US brand name: Leqembi Iqlik®), which was approved by the FDA on July 13, now is available in the US for initiation therapy for early Alzheimer’s disease[1].Leqembi Iqlik is the first-of-its-kind anti-amyloid treatment that offers at-home dosing for initiation and maintenance (approved in the US).

Leqembi Iqlik is administered via an autoinjector, introducing a convenient alternative to intravenous (IV) infusion from the start of treatment. For initiation, the approved regimen is 500 mg once weekly, delivered as two 250 mg injections, each administered in approximately 15 seconds.

Expanding convenience and flexibility in Alzheimer’s care

The availability of Leqembi Iqlik for both initiation and maintenance therapy in the US offers patients and carers greater convenience and flexibility throughout the treatment journey. At-home administration reduces the need for IV infusions and clinic visits, making treatment easier to integrate into daily life. Leqembi Iqlik may also help reduce healthcare resource utilization associated with IV administration. As with intravenous treatment, MRI monitoring for ARIA is required before treatment initiation and at specified time points thereafter.

Please see full Prescribing Information for Leqembi, including Boxed WARNING.

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The information was released for public disclosure, through the agency of the contact person below, on August 24, 2026, at 2:05 pm CEST.
For further information, please contact:
Oskar Bosson, Chief Investor Relations & Communications Officer

E-mail: oskar.bosson@bioarctic.com

Telephone: +46 704 107 180
Jenny Ljunggren, External Communications and Investor Relations Manager

E-mail: jenny.ljunggren@bioarctic.com

Telephone: +46 76 013 86 08
About Leqembi® (lecanemab)
Leqembi is the result of a strategic research alliance between BioArctic and Eisai. It is a humanized immunoglobulin gamma 1 (IgG1) monoclonal antibody directed against aggregated soluble (protofibril) and insoluble forms of amyloid-beta (Aβ).

Leqembi is approved in 53 countries and is under regulatory review in 6 countries. Following the initial phase with treatment every two weeks for 18 months, intravenous (IV) maintenance dosing with treatment every four weeks is approved in 8 countries, including the United Kingdom, China, the US and Japan, and applications have been filed in 12 countries and regions. In the US, Leqembi Iqlik®is approved for subcutaneous dosing with an autoinjector as a starting dose and maintenance treatment of early Alzheimer’s disease. In November 2025, a new drug application for subcutaneous formulation of Leqembi was submitted in Japan. In December 2025, Leqembi was included in the “Commercial Insurance Innovative Drug List”,recently introduced by the National Healthcare Security Administration (NHSA) of China.In January 2026, the Biologics License Application for subcutaneous formulation of Leqembi was accepted in China and in February, the application was designated for priority review.

Since July 2020, Eisai’s Phase 3 clinical study (AHEAD 3-45) with lecanemab in individuals with preclinical Alzheimer’s disease meaning they are clinically normal and have intermediate or elevated levels of amyloid in their brains, is ongoing. The study was fully recruited in October 2024. AHEAD 3-45 is a four-year study conducted as a public-private partnership between Eisai, Biogen and the Alzheimer's Clinical Trial Consortium that provides the infrastructure for academic clinical trials in Alzheimer’s disease and related dementias in the US, funded by the National Institute on Aging, part of the National Institutes of Health. Since January 2022, the Tau NexGen clinical study for Dominantly Inherited Alzheimer’s disease (DIAD), that is conducted by Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU), led by Washington University School of Medicine in St. Louis, is ongoing and includes lecanemab as the backbone anti-amyloid therapy.

About the collaboration between BioArctic and Eisai
Since 2005, BioArctic has a long-term collaboration with Eisai regarding the development and commercialization of drugs for the treatment of Alzheimer’s disease. The most important agreements are the Development and Commercialization agreement for the lecanemab antibody, which was signed 2007, and the Development and Commercialization agreement for the antibody lecanemab back-up for Alzheimer’s disease, which was signed 2015. In 2014, Eisai and Biogen entered into a joint development and commercialization agreement for lecanemab. Eisai is responsible for the clinical development, application for market approval and commercialization of the products for Alzheimer’s disease. BioArctic has the right to commercialize lecanemab in the Nordic region and is currently preparing for commercialization in the Nordics together with Eisai. BioArctic has no development costs for lecanemab in Alzheimer’s disease and is entitled to payments in connection with sales milestones as well as royalties on global sales.

About BioArctic AB
BioArctic AB (publ) is a Swedish research-based biopharma company focusing on innovative treatments that can delay or stop the progression of neurodegenerative diseases. The company invented Leqembi® (lecanemab) – the world's first drug proven to slow the progression of the disease and reduce cognitive impairment in early Alzheimer's disease. Leqembi has been developed together with BioArctic’s partner Eisai, who are responsible for regulatory interactions and commercialization globally. In addition to Leqembi, BioArctic has a broad research portfolio with antibodies against Parkinson's disease and ALS as well as additional projects against Alzheimer's disease. Several of the projects utilize the company's proprietary BrainTransporter™ technology, which has the potential to actively transport antibodies across the blood-brain barrier to enhance the efficacy of the treatment. BioArctic's B share (BIOA B) is listed on Nasdaq Stockholm Large Cap. For further information, please visitwww.bioarctic.com.