Biogen Gains as Alzheimer's Drug Leqembi Secures UK Approval
Regulators approve less-frequent maintenance dosing for Leqembi, bolstering its competitive stance against rivals in the growing Alzheimer's market.
Biogen Inc. (BIIB) shares climbed after UK regulators approved a less-frequent maintenance dosing schedule for Leqembi, the company’s pivotal Alzheimer's treatment developed with partner Eisai. The decision is a key commercial victory, aimed at improving patient convenience and strengthening the drug's foothold in a fiercely competitive market.
The UK’s Medicines and Healthcare products Regulatory Agency (MHRA) gave the green light for an intravenous maintenance dose of Leqembi to be administered once every four weeks. This follows the initial bi-weekly induction phase, offering a more manageable long-term treatment plan for patients with early-stage Alzheimer's disease. The news was met with positive investor sentiment, with Biogen's stock rising over 3% in the trading session prior to the formal announcement, closing at $164.73.
The approval addresses a critical aspect of chronic disease management: treatment burden. For patients and caregivers, a monthly infusion is significantly less disruptive than a bi-weekly schedule, a factor that could influence physician and patient preference. This strategic enhancement comes as Biogen and Eisai are locked in a global battle for market share with Eli Lilly's competing Alzheimer's therapy, donanemab.
Analysts have been watching the rollout closely. Following the news, Stifel upgraded Biogen's stock from 'Hold' to 'Buy', reflecting renewed confidence in the company's commercial strategy for Leqembi. The drug is a cornerstone of Biogen’s efforts to pivot from its aging portfolio of multiple sclerosis treatments and establish a new revenue driver. The consensus rating among analysts remains a 'Moderate Buy,' with an average price target of $176.72.
The competitive landscape for Alzheimer's treatments has intensified dramatically. Eli Lilly’s donanemab received marketing authorization in the UK in October 2024 and in the European Union in September 2025. While both drugs are designed to remove amyloid plaques from the brain, clinical data suggests nuanced differences. A Phase III study showed donanemab slowed cognitive decline by 35% over 18 months, a figure that has been a key part of its marketing push.
The market opportunity is substantial. The UK Alzheimer's therapeutics market was valued at approximately $263 million in 2024 and is projected to nearly double to almost $500 million by 2033, according to market research from Grand View Research. The broader European market for neurodegenerative diseases is expected to expand from $1.15 billion in 2022 to $4.5 billion by 2030.
In a statement released by Biogen and Eisai, the companies emphasized that the approval provides "greater flexibility for patients and their caregivers in managing long-term treatment." The decision was based on modeling of data from the companies' Phase 3 Clarity AD study, which formed the basis of Leqembi's initial approvals worldwide.
For Biogen, which has a market capitalization of approximately $23.7 billion, the successful commercialization of Leqembi is critical. With quarterly revenue growth at a modest 2.8% year-over-year, the company is counting on its Alzheimer’s franchise to drive future growth. This latest regulatory milestone in the UK is a crucial step in that direction, but the path forward will be defined by the intense commercial and clinical rivalry with Eli Lilly for a dominant position in this high-stakes therapeutic area.