Eisai Co. and Biogen Inc. have announced that the Department of Health in Hong Kong has approved humanised anti-soluble aggregated amyloid-beta (Aβ) monoclonal antibody 'Leqembi' for treatment of Alzheimer’s disease (AD).

Treatment with Leqembi should be initiated in patients with mild cognitive impairment (MCI) or mild dementia stage of disease, the population in which treatment was initiated in clinical trials.

Leqembi selectively binds to soluble Aβ aggregates (protofibrils), as well as insoluble Aβ aggregates (fibrils) which are a major component of Aβ plaques, thereby reducing both Aβ protofibrils and Aβ plaques in the brain. Leqembi is the first approved treatment shown to reduce the rate of disease progression and to slow cognitive and functional decline through this mechanism. Hong Kong is the fifth approval, following approvals in the US, Japan, China, and South Korea.

Thiss approval in Hong Kong is based on the large global Phase 3 Clarity AD study. In the Clarity AD study, Leqembi met its primary endpoint and all key secondary endpoints with statistically significant results. In Hong Kong, 9.3% of people aged 70 years and older were living with dementia, increasing to 32% of those aged 85 years and older. Of whom with dementia, 73.5% were reported to have Alzheimer's disease.