Leqembi Pen was approved in Japan on September 16, 2026, and has now been included in Japan's National Health Insurance (NHI) Drug Price List. It is the first and only anti-amyloid treatment in Japan that enables at-home administration.

Leqembi Pen is administered using an autoinjector and provides patients with a once-weekly subcutaneous treatment option in addition to intravenous (IV) administration every two weeks in a medical facility. The approved dose is 500 mg once weekly, administered through two pens.

The availability of Leqembi Pen provides patients and care partners with greater flexibility in how treatment is administered. At-home administration may reduce the need for clinic visits associated with IV treatment and make treatment easier to integrate into everyday life. It may also reduce the use of healthcare resources associated with IV administration. After appropriate education and training, treatment can be self-administered by the patient or administered by a family member or care partner under the management and guidance of a physician.

As with IV administration, MRI monitoring for amyloid-related imaging abnormalities (ARIA) is required prior to treatment initiation and at specified time points thereafter.

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The information was released for public disclosure, through the agency of the contact person below, on November 13, 2026, at 08:00 am CET.
 

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 six countries and regions. Following the initial phase with treatment every two weeks for 18 months, intravenous (IV) maintenance dosing with treatment every four weeks is approved in nine countries and regions, including the US, Japan, China and the United Kingdom, and applications have been filed in eleven 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. Subcutaneous initiation treatment was approved in China and Japan in September 2026, and applications are under review in four countries.

Eisai's Phase 3 clinical study (AHEAD 3-45) with lecanemab in individuals with preclinical Alzheimer's disease has been ongoing since July 2020. These individuals are clinically normal and have intermediate or elevated levels of amyloid in their brains. 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
BioArctic has a long-term collaboration with Eisai since 2005 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 in 2007, and the Development and Commercialization agreement for the antibody lecanemab back-up for Alzheimer's disease, which was signed in 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 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 therapies 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 visit www.bioarctic.com.