Biogen and Eisai have announced that the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) has approved an updated dosing regimen for their jointly developed Alzheimer’s disease treatment, LEQEMBI (lecanemab). LEQEMBI is a humanised, anti-soluble aggregated amyloid-beta (Aβ) monoclonal antibody.
The MHRA first authorised LEQEMBI in August 2024 for the treatment of mild cognitive impairment (MCI) and mild dementia due to Alzheimer’s disease in adult patients who meet specific diagnostic criteria.
Alzheimer’s disease is a progressive neurodegenerative disease characterised by the formation of plaques – protein deposits made of amyloid-beta aggregates and neurofibrillary tangles made of tau protein – in the brain. In the UK, estimates suggest that around 982,000 people are living with dementia, with Alzheimer’s disease being the cause in 60-70% of cases. These figures are expected to rise as the population ages.
The latest approval enables the use of a once-monthly intravenous (IV) maintenance dose, administered every four weeks. After completing 18 months of the initial regimen – 10 mg/kg IV every two weeks – patients may either transition to the monthly maintenance schedule or continue the original dosing approach.
The initial LEQEMBI dosing regimen is currently approved in 51 countries and remains under review in a further nine. The monthly maintenance dose has now been approved in the US, China and the UK, with regulatory submissions under consideration in four additional countries and regions. Eisai is responsible for leading development and regulatory activities, while Biogen supports commercialisation and co-promotion.
LEQEMBI’s regulatory progress follows positive results from Eisai’s global phase 3 Clarity AD trial, which demonstrated statistically significant outcomes across all primary and key secondary endpoints. A second phase 3 study evaluating lecanemab in patients with preclinical Alzheimer’s disease commenced in July 2020 and is ongoing.