Leqembi is already approved in the UK for intravenous (IV) treatment every two weeks.[1] The proposed intravenous maintenance dosing variation application offers the possibility to reduce lecanemab infusion frequency from every two weeks to every four weeks for eligible adult patients with early Alzheimer's disease in the UK after the initial 18 months of treatment of the currently approved dosing regimen.

The submission is part of Eisai's ongoing commitment to addressing the unmet needs of people living with Alzheimer's disease, healthcare systems and wider society. The MHRA will evaluate the application and decide whether to approve or reject the proposal.

Alzheimer's disease is a chronic disease which progresses in stages and increases in severity over time.[2] Alzheimer's disease is the leading cause of death in the UK [3], with early Alzheimer's disease usually being the first stage of the disease where symptoms become noticeable, such as forgetting recent events or conversations.[4]^{, [5]} As Alzheimer's disease progresses, everyday activities, hobbies and social engagements become more challenging, and independence is lost.^{4, 5} 

Leqembi is approved in the US, Japan, EU, China, United Kingdom and other markets.

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The information was released for public disclosure, through the agency of the contact persons below, on April 30, 2025, at 09:30 CET.
 

For further information, please contact: 
Charlotte af Klercker, Senior Director Sustainability and Communications
E-mail: charlotte.afklercker@bioarctic.com
Telephone: +46 73 515 09 70

Anders Martin-Löf, CFO 
E-mail:  anders.martin-lof@bioarctic.com
Telephone: +46 70 683 79 77

About lecanemab (Leqembi^®)
Lecanemab 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).

Lecanemab is approved in the U.S., Japan, EU, China, United Kingdom, and several other markets for the treatment of mild cognitive impairment (MCI) due to Alzheimer's disease (AD) and mild AD dementia.

Lecanemab's approvals in these countries were primarily based on Phase 3 data from Eisai's global Clarity AD clinical trial, in which it met its primary endpoint and all key secondary endpoints with statistically significant results.

For UK prescribing information, see Lecanemab United Kingdom Summary of Product Characteristics. Available at: https://www.medicines.org.uk/emc/product/15908. ►:This medicine is subject to additional monitoring. This will allow quick identification of new safety information.

Eisai has also submitted applications for regulatory approval of lecanemab in several other countries and regions. In January 2025, the supplemental Biologics License Application (sBLA) for intravenous (IV) maintenance dosing of the treatment was approved in the U.S. After an 18 months initiation phase with once every two weeks of dosing, a transition to the maintenance dosing regimen of 10 mg/kg once every four weeks or continuing 10 mg/kg once every two weeks may be considered. Additionally, the U.S. Food and Drug Administration (FDA) accepted Eisai's Biologics License Application (BLA) for the Leqembi subcutaneous autoinjector for weekly maintenance dosing in January 2025 and set a PDUFA action date for August 31, 2025.

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 Leqembi 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 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 visit www.bioarctic.com.