Leqembi is a humanised anti-soluble aggregated amyloid-beta monoclonal antibody.
The development follows the August 2024 approval for treating mild cognitive impairment (MCI) and mild dementia caused by Alzheimer’s in adults who are apolipoprotein E ε4 non-carriers or heterozygotes in the UK.
Following an initial 18-month regimen of 10mg/kg IV dosing every two weeks, patients may now transition to the maintenance schedule of 10mg/kg IV every four weeks or continue the biweekly dose.
Alzheimer’s is characterised by the buildup of amyloid-beta aggregates plaques and neurofibrillary tangles made of tau protein in the brain.
Given the Alzheimer’s biomarkers reaccumulation and return to placebo rate of decline once therapy ceases, it is crucial to continue maintenance treatment following the initial therapy for 18 months.
This approach is vital for slowing the progression of the condition and prolonging the therapeutic benefits, assisting patients in preserving their identity for a more extended period.
The approval aligns with recent regulatory decisions in countries including China and the US, informed by Phase III Clarity clinical trial data meeting primary and key secondary endpoints.
Eisai is acting as the lead for the antibody’s development and regulatory submissions worldwide.
Both Biogen and Eisai are jointly commercialising and promoting the product, with the latter holding final decision-making authority.