Eisai and Biogen gain Priority Review in China for subcutaneous LEQEMBI (lecanemab) autoinjector. Enables weekly home dosing to ease Alzheimer’s care amid 17M patient burden.
Written By: Sana Khan BPharm
Reviewed By: Pharmacally Editorial Team
Eisai Co., Ltd. and Biogen Inc. have received Priority Review designation in China for the subcutaneous autoinjector formulation of LEQEMBI (lecanemab), advancing efforts to expand home-based treatment options for patients with early Alzheimer’s disease.
The Biologics License Application for the subcutaneous formulation was accepted in January 2026 and is being reviewed under the Priority Review and Approval Procedure of China’s National Medical Products Administration, a pathway designed to accelerate access to medicines with clear clinical value.
What the subcutaneous option could change
If approved, the subcutaneous autoinjector would allow LEQEMBI to be administered at home from the start of treatment. The once-weekly 500 mg dose is delivered as two 250 mg injections, each taking approximately 15 seconds. This approach would provide an alternative to the current intravenous regimen, which requires hospital-based infusions every two weeks.
The shift to at-home administration could reduce treatment burden for patients and caregivers while lowering healthcare resource use related to infusion preparation and monitoring.
Alzheimer’s disease burden in China
Eisai estimates that around 17 million people in China were living with mild cognitive impairment or mild dementia due to Alzheimer’s disease in 2024, a number expected to increase as the population ages.
About LEQEMBI and its mechanism
LEQEMBI is a humanized IgG1 monoclonal antibody that targets aggregated forms of amyloid-beta, particularly protofibrils, which are believed to contribute to neuronal injury and cognitive decline in Alzheimer’s disease. The therapy originated from a research collaboration between Eisai and BioArctic, with Eisai holding global development and commercialization rights.
Global regulatory and clinical landscape
Globally, LEQEMBI has been approved in 53 countries and regions, including the United States, China, Japan, Europe, South Korea, Taiwan, and Saudi Arabia. Intravenous maintenance dosing every four weeks, following an initial biweekly phase, has already been approved in several major markets.
In the United States, subcutaneous maintenance dosing was approved in August 2025. A supplemental application for subcutaneous initiation dosing was accepted in January 2026 and granted Priority Review, with a regulatory decision expected by May 24, 2026. Japan also received an application for a subcutaneous injectable formulation in late 2025.
Market access in China
In China, LEQEMBI has been available in the private market since June 2024. In December 2025, the intravenous formulation was included in the Commercial Insurance Innovative Drug List introduced by the National Healthcare Security Administration, supporting the development of insurance coverage for the therapy.
Collaboration framework
Eisai leads global development and regulatory submissions for lecanemab, with Eisai and Biogen co-commercializing and co-promoting the product worldwide. Eisai retains final decision-making authority and oversees distribution and medical information activities in China.
References
Biologics License Application for Subcutaneous Formulation of “LEQEMBI®” (lecanemab) for the Treatment of Early Alzheimer’s Disease Designated for Priority Review in China, 08 February 2026, Biologics License Application for Subcutaneous Formulation of “LEQEMBI®” (lecanemab) for the Treatment of Early Alzheimer’s Disease Designated for Priority Review in China | Biogen
Biologics License Application for Subcutaneous Formulation of “LEQEMBI®” (lecanemab) for the Treatment of Early Alzheimer’s Disease Designated for Priority Review in China, 09 February 2026, https://www.eisai.com/news/2026/pdf/enews202608pdf.pdf