Eisai and Biogen have reached a new regulatory milestone in China with the acceptance of a Biologics License Application (BLA) for the subcutaneous formulation of LEQEMBI (lecanemab) by the National Medical Products Administration (NMPA). The application covers a subcutaneous autoinjector (SC-AI) version of the anti-amyloid beta protofibril antibody, which is already approved in intravenous (IV) form in several markets for the treatment of early Alzheimer’s disease (AD).
If approved, the subcutaneous formulation would allow patients to receive a once-weekly 500 mg dose—administered as two 250 mg injections—at home from the initiation of treatment. This would offer an alternative to the current IV infusion, which requires administration in a hospital or clinical setting. Each autoinjector injection takes approximately 15 seconds, potentially making treatment more convenient for patients and caregivers.
The move toward a subcutaneous, at-home option could significantly reduce the burden on healthcare systems by decreasing the need for infusion preparation, clinic visits, and nurse monitoring associated with IV dosing. Eisai and Biogen believe this streamlined approach could improve access to treatment and simplify the overall care pathway for patients with Alzheimer’s disease, particularly in a large and aging population such as China’s.
According to Eisai, an estimated 17 million people in China were living with mild cognitive impairment (MCI) or mild dementia due to Alzheimer’s disease in 2024, a figure expected to rise as the population continues to age. The availability of a more flexible dosing option could play a critical role in addressing the growing demand for effective and manageable treatments.
LEQEMBI targets amyloid beta protofibrils, which are believed to be among the most toxic forms of amyloid beta and are thought to play a central role in the neuronal injury and cognitive decline associated with Alzheimer’s disease. Protofibrils can damage brain cells directly, disrupt cell membranes, and impair synaptic connections, while also contributing to the formation of insoluble amyloid plaques. By reducing protofibrils, lecanemab is designed to slow disease progression and cognitive deterioration.
Eisai leads global development and regulatory submissions for LEQEMBI, while Eisai and Biogen co-commercialize and co-promote the therapy worldwide. Eisai retains final decision-making authority and will be responsible for product distribution in China, supported by information and education activities conducted through specialized medical representatives.
The NMPA’s acceptance of the BLA marks an important step toward expanding treatment options for Alzheimer’s disease patients in China and underscores the companies’ ongoing efforts to improve convenience and accessibility in disease-modifying therapies.