Eisai seeks marketing authorisation for Lecanemab to treat early Alzheimer's disease in Great Britain

The MAA is based on the results of the confirmatory Phase III Clarity AD study and Phase IIb clinical study (Study 201), which demonstrated that lecanemab treatment showed a reduction of clinical decline in early AD, and is subject to a validation to determine whether it will be accepted by the MHRA. Lecanemab selectively binds and eliminates soluble, toxic Aβ aggregates (protofibrils) that are thought to contribute to the neurotoxicity in AD. As such, lecanemab may have the potential to have an effect on disease pathology and the progression of the disease. The Clarity AD study of lecanemab met its primary endpoint and all key secondary endpoints with highly statistically significant results.

Lecanemab is the result of a strategic research alliance between Eisai and BioArctic. It is a humanized immunoglobulin gamma 1 (IgG1) monoclonal antibody directed against aggregated soluble (protofibril) and insoluble forms of amyloid-beta (Aβ).

In the U.S., lecanemab was granted accelerated approval for Alzheimer’s disease (AD) by the U.S. Food and Drug Administration (FDA) on January 6, 2023. On the same day, Eisai submitted a supplemental Biologics License Application (sBLA) to the FDA for approval under the traditional pathway. This application was accepted, and has been granted Priority Review, with a Prescription Drug User Fee Act (PDUFA) action date of July 6, 2023. In Europe, Eisai submitted a MAA to the European Medicines Agency (EMA) on January 9, 2023, which was accepted on January 26, 2023. In Japan, Eisai submitted a Marketing Authorization Application to the Pharmaceuticals and Medical Devices Agency (PMDA) on January 16, 2023, and Priority Review was designated by the Ministry of Health, Labour and Welfare (MHLW) on January 26, 2023. In China, Eisai initiated submission of data for a BLA to the National Medical Products Administration (NMPA) of China in December 2022, which was designated for Priority Review on February 27, 2023. In Canada, Eisai submitted a New Drug Submission (NDS) to Health Canada on March 31, 2023, and was accepted on May 15 of the same year.

Lecanemab is indicated for the treatment of AD in the U.S. Treatment with lecanemab should be initiated in patients with mild cognitive impairment or mild dementia stage of disease, the population in which treatment was initiated in clinical trials. There are no safety or effectiveness data on initiating treatment at earlier or later stages of the disease than were studied. This indication is approved under accelerated approval based on reduction in Aβ plaques observed in patients treated with lecanemab. Continued approval for this indication may be contingent upon verification of clinical benefit in a confirmatory trial.

Eisai has completed a lecanemab subcutaneous bioavailability study, and subcutaneous dosing is currently being evaluated in the Clarity AD OLE.

Since July 2020 the Phase III clinical study (AHEAD 3-45) for individuals with preclinical AD, meaning they are clinically normal and have intermediate or elevated levels of amyloid in their brains, is ongoing. AHEAD 3-45 is conducted as a public-private partnership between the Alzheimer’s Clinical Trial Consortium that provides the infrastructure for academic clinical trials in AD and related dementias in the U.S, funded by the National Institute on Aging, part of the National Institutes of Health, Eisai and Biogen. The Tau NexGen clinical study for Dominantly Inherited AD (DIAD), that is conducted by Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU), led by Washington University School of Medicine in St. Louis, has been ongoing since January 2022.

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