LEQEMBI(R) (Lecanemab) Approved for the Treatment of Alzheimer’s Disease in Australia

TOKYO and CAMBRIDGE, Mass., Sept. 24, 2025 – (JCN Newswire) – Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) and Biogen Inc. (Nasdaq: BIIB, Corporate head office: Cambridge, Massachusetts, CEO: Christopher A. Viehbacher, “Biogen”) revealed today that the Therapeutic Goods Administration (TGA)of Australia has actually authorized the humanized anti-soluble aggregated amyloid-beta (Aβ) monoclonal antibody “LEQEMBI ®” (brand, generic name: lecanemab) for moderate cognitive problems (MCI) or moderate dementia due to Alzheimer’s illness (ADVERTISEMENT) (jointly described as early advertisement) in grownups who are either ApoEε4 * non-carriers or heterozygous providers.

In action to February 2025 TGA choice not to authorize lecanemab as a treatment for individuals with early advertisement, in March 2025, Eisai asked for an evaluation by the Administrative Review Tribunal. As an outcome of conversations throughout this procedure, the TGA and Eisai reached an arrangement that caused the approval of LEQEMBI.

In Australia, the variety of individuals coping with dementia was approximated to be roughly 425,000 in 2024, and is reported to increase to almost 1,100,000 by 2065.1 advertisement is thought about the most typical reason for dementia, normally representing 60-70% of cases.2 advertisement is a progressive, ruthless illness with amyloid beta (Aβ) and tau as trademarks that is triggered by a constant underlying neurotoxic procedure that starts before amyloid plaque elimination and continues later.3,4,5 Only LEQEMBI battles advertisement in 2 methods– targeting both the harmful protofibrils ** and amyloid plaque 2, which can affect tau downstream.

Eisai acts as the lead for lecanemab’s advancement and regulative submissions internationally with Eisai and Biogen co-commercializing and co-promoting the item and Eisai having last decision-making authority.

* Apolipoprotein E is a protein associated with the metabolic process of fats in people. It is linked in advertisement. Individuals with just one (heterozygous) or no copy (non-carriers) of the ApoE ε4 gene are less most likely to experience ARIA than individuals with 2 ApoE ε4 copies (homozygous).2 ARIA is an acknowledged crucial negative effects with lecanemab that includes swelling and prospective bleeding in the brain.6,7

** Protofibrils are thought to add to the brain injury that accompanies advertisement and are thought about to be the most poisonous kind of Aβ, having a main function in the cognitive decrease connected with this progressive, incapacitating condition.3 Protofibrils trigger injury to nerve cells in the brain, which in turn, can adversely affect cognitive function by means of numerous systems, not just increasing the advancement of insoluble Aβ plaques however likewise increasing direct damage to brain cell membranes and the connections that transfer signals in between afferent neuron or afferent neuron and other cells. It is thought the decrease of protofibrils might avoid the development of advertisement by decreasing damage to nerve cells in the brain and cognitive dysfunction.4

For more information, please see: https://www.eisai.com/news/2025/pdf/enews202566pdf.pdf

Subject: Press release summary