Who Owns Aricept?

Eisai chemists discovered donepezil at the company's Tsukuba research center in the 1980s, pursuing a cholinesterase inhibitor that could slow the cognitive decline of Alzheimer's disease. The drug entered clinical development in the late 1980s.

The FDA approved Aricept on 25 November 1996 for mild to moderate Alzheimer's disease, making it the second cholinesterase inhibitor approved for the condition after tacrine, but with a far better safety profile that made it the standard of care. Eisai co-marketed it in the US with Pfizer, and it launched across Europe, Japan, and other markets through the late 1990s.

Aricept became the world's best-selling Alzheimer's drug, reaching peak global sales above $3 billion annually. The 2006 approval of a severe-disease indication and the 2010 launch of the 23 mg dose extended the franchise.

US patent expiry in November 2010 triggered one of the industry's largest generic entries, and branded sales fell sharply. Eisai's legal efforts to protect the franchise, including a dispute over the forced switch to the 23 mg formulation, drew antitrust scrutiny and a federal court ruling in 2015 ordering continued availability of the older formulation.

Today Aricept remains available as a branded product in many markets, but donepezil is overwhelmingly dispensed as a generic. Eisai's dementia focus has moved to Leqembi (lecanemab), the anti-amyloid antibody developed with Biogen and approved in 2023.