Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) announced today the presentation of data from the company’s extensive Alzheimer’s disease (AD) pipeline, including six oral presentations that will provide deeper insights into lecanemab’s potential as a treatment for early AD. Eisai initiated a rolling submission of a Biologics License Application (BLA) for lecanemab, an investigational anti-amyloid beta (Aβ) protofibril antibody, for the treatment of early AD, to the U.S. Food and Drug Administration (FDA) under the accelerated approval pathway in September 2021. The lecanemab data and additional research findings from Eisai’s robust AD pipeline will be featured in 10 presentations, including five late breaker oral presentations, at the 14th Clinical Trials on Alzheimer’s Disease (CTAD) conference, November 9-12, 2021, in Boston, Massachusetts and virtually.


“The findings Eisai will present at CTAD provide scientific insights into the potential role of lecanemab in the treatment of early Alzheimer’s disease as well as the relationship between clearance of amyloid-beta plaque from the brain, changes in blood-based biomarkers and clinical outcomes,” said Michael Irizarry, M.D., Vice President, Deputy Chief Clinical Officer, Neurology Business Group, Eisai Inc. “We are working to advance lecanemab and our other targeted investigational compounds as quickly as possible in our commitment to bringing solutions to patients and their families.”


The focus on AD has historically been on alleviating cognitive, functional, and behavioral symptoms, but there has been significant progress in understanding the biological mechanisms of the disease and Eisai’s investigational pipeline aims to treat the range of underlying pathophysiology, including amyloid, tau and neurodegeneration.


“With lecanemab’s rolling BLA submission to the FDA under the accelerated approval pathway, completion of enrollment of 1,795 patients in the confirmatory Phase 3 Clarity AD clinical trial, initiation of a lecanemab subcutaneous dosing Phase 1 study and the ongoing Phase 3 AHEAD 3-45 study in people with pre-clinical Alzheimer’s disease, it is an exciting time for lecanemab and Eisai’s AD franchise,” said Ivan Cheung, Chairman, Eisai Inc., Senior Vice President, President Neurology Business Group and Global Alzheimer’s Disease Officer, Eisai Co., Ltd. “We are optimistic about the promise lecanemab and other investigational compounds in our robust pipeline may have for people living with Alzheimer’s disease.”


Major Presentations Provide Deeper Scientific Insights into Lecanemab’s Potential as a Treatment for Early AD

  • Roundtable: Presentation of the latest lecanemab data, followed by esteemed faculty, Drs. Jeffrey Cummings, Randall Bateman and Christopher van Dyck, facilitating a conversation about the results and insights useful to the broader AD community (Oral Roundtable 5)
  • Oral presentation about consistency of efficacy assessments across various statistical methods from the lecanemab Phase II proof-of-concept study (Study 201) in people living with early AD (LB9)
  • Oral presentation regarding the introduction of plasma biomarker screening for Phase 3 AHEAD 3-45 study for preclinical AD (LB4)
  • Oral presentation outlining the baseline characteristics for the Phase 3 Clarity AD clinical trial for people living with early AD (ROC22)

■ CTAD 2021 Presentations Relating to Eisai’s Investigational Compounds and Research

Topic, Session,
Time (Eastern Standard Time)
Title, Presenter/Author

Oral communication (onsite),
Roundtable 5
Wednesday, November 10;

2:00 – 2:30 p.m.

Assessment of the Clinical Effects of Lecanemab, the Correlation of Plasma Aβ 42/40 Ratio with Changes in Brain Amyloid PET SUVr, and Safety from the Core and Open Label Extension of the Phase 2 Proof-of-Concept Study, BAN2401-G000-201, in Subjects with Early Alzheimer’s Disease 

Presenter: C. Swanson, J. Cummings, R. Bateman and C. van Dyck

Oral communication (onsite), LB9
Thursday, November 11;

11:20 – 11:35 a.m.

Consistency of Efficacy Assessments Across Various Statistical Methods from the Lecanemab Phase 2 Proof-of-Concept Study, BAN2401-G000-201, in Subjects with Early Alzheimer’s Disease


Presenter: DA Berry

Oral communication (onsite), LB4
Thursday, November 11;

9:35 – 9:50 a.m.

Introduction of Plasma Biomarker Screening for the AHEAD 3-45 Study


Presenter: R. Sperling

Oral communication (virtual), ROC22
Friday, November 12;

On-demand from 8:00 a.m.

Baseline Characteristics for CLARITY-AD: A Phase 3 Placebo-Controlled, Double-Blind, Parallel-Group, 18-Month Study Evaluating Lecanemab (BAN2401) in Early Alzheimer's Disease


Presenter: C. Swanson

Oral communication (virtual), ROC23
Friday, November 12;

On-demand from 8 a.m.

A Stepwise Tier-Based Approach for Determining Patient Eligibility in CLARITY AD: A Phase 3 Placebo-Controlled, Double-Blind Study to Confirm the Safety and Efficacy of Lecanemab (BAN2401) 10 mg/kg Biweekly in Patients with Early Alzheimer's Disease


Presenter: M. Gee


Poster (onsite), P42

Accelerating Alzheimer’s Disease Drug Development by Pre-Competitive Data Sharing with the Critical Path for Alzheimer’s Disease (CPAD) Consortium for Generation of High-Impact Quantitative Drug Development Tools


Presenter: S. Sivakumaran, et al


Poster (remote), RP27

Decision-Making and Reactions on Genetic Testing in Alzheimer’s Disease Among Patients, Caregivers and Healthcare Professionals


Authors: A. Tahami, et al


Poster (remote), RP4

Improving Screening Efficiency Through Alternate Story Recall


Authors: T. Doherty, et al

Oral communication (virtual), LBR8 
Tuesday, November 9;

On-demand from 8:00 a.m.

Prediction of Brain Amyloid Pathology Using the C2N PrecivityAD™ Test in the MissionAD Study Samples


Presenter: D. Verbel

Oral communication (virtual), LBR9
Tuesday, November 9;

On-demand from 8:00 a.m.

Evaluation of Tau Deposition Using [18F] PI-2620 PET in MCI and Early AD: A MissionAD Tau Sub-Study


Presenter: S. Bullich


■ Key Biogen Abstract Presentations for Joint Assets

Topic, Session,
Time (Eastern Standard Time)
Title, Presenter/Author

Oral communication (virtual), LBR2
Tuesday, November 9;

On-demand from 8:00 a.m.

Baseline EMBARK data from EMERGE, ENGAGE, and PRIME Participants in the EMBARK Re-Dosing Study      


Presenter: S. Cohen 

Oral communication (virtual), LBR4 
Tuesday, November 9;

On-demand from 8:00 a.m.

Defining a Standardized MRI Acquisition Protocol to be Proposed to ICARE AD Sites for Baseline and ARIA Monitoring


Presenter: T. Benzinger

Oral Communication, (onsite),
Roundtable 8

Thursday, November 11; from 5:15 p.m.

Dose and time dependent changes in plasma ptau181 in patients treated with aducanumab in the ENGAGE and EMERGE trials


Presenter: O. Hanson


Poster (onsite), LP22

Updated US Prevalence Estimates Accounting for Racial and Ethnic Diversity for Trials and Therapies Targeting Mild Cognitive Impairment Due to AD and Mild AD Dementia


Authors: N. Maserejian, et al

This release discusses investigational uses of agents in development and is not intended to convey conclusions about efficacy or safety. There is no guarantee that such investigational agents will successfully complete clinical development or gain health authority approval.




Eisai Co., Ltd.

Public Relations Department

TEL: +81-(0)3-3817-5120


Eisai Inc. (U.S.)

Libby Holman





[Notes to editors]


  1. 1. About lecanemab (Development Code: BAN2401)

Lecanemab is an investigational humanized monoclonal antibody for Alzheimer’s disease (AD) that is the result of a strategic research alliance between Eisai and BioArctic. Lecanemab selectively binds to neutralize and eliminate soluble, toxic amyloid-beta (Aβ) aggregates (protofibrils) that are thought to contribute to the neurodegenerative process in AD. As such, lecanemab may have the potential to have an effect on disease pathology and to slow down the progression of the disease. With regard to the results from pre-specified analysis at 18 months of treatment, Study 201 demonstrated reduction of brain Aβ accumulation (P<0.0001) and slowing of disease progression measured by ADCOMS* (P<0.05) in early AD subjects. The study did not achieve its primary outcome measure** at 12 months of treatment. The Study 201 open-label extension was initiated after completion of the Core period and a Gap period off treatment (average of 24 months) to evaluate safety and efficacy, and is underway.


Eisai obtained the global rights to study, develop, manufacture and market lecanemab for the treatment of AD pursuant to an agreement concluded with BioArctic in December 2007. In March 2014 Eisai and Biogen entered into a joint development and commercialization agreement for lecanemab and the parties amended that agreement in October 2017. Currently, lecanemab is being studied in a pivotal Phase 3 clinical study in symptomatic early AD (Clarity-AD), following the outcome of the Phase 2 clinical study (Study 201). In July 2020 the Phase 3 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, was initiated. 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 Alzheimer’s Disease and related dementias in the U.S, funded by the National Institute on Aging, part of the National Institutes of Health, and Eisai.


* Developed by Eisai, ADCOMS (AD Composite Score) combines items from the ADAS-Cog (Alzheimer’s Disease Assessment Scale-cognitive subscale), CDR (Clinical Dementia Rating) and the MMSE (Mini-Mental State Examination) scales to enable a sensitive detection of changes in clinical functions of early AD symptoms and changes in memory.

** An 80% or higher estimated probability of demonstrating 25% or greater slowing in clinical decline at 12 months treatment measured by ADCOMS from baseline compared to placebo              


  1. 2. About Aducanumab-avwa

Biogen licensed aducanumab, a human monoclonal antibody, from Neurimmune in 2007 under a collaborative development and license agreement. Since October 2017, Biogen and Eisai have collaborated on the development and commercialization of aducanumab globally.


  1. 3. About the Collaboration between Eisai and Biogen for AD

Eisai and Biogen are collaborating on the joint development and commercialization of AD treatments. Eisai serves as the lead in the co-development of lecanemab.


  1. 4. About the Collaboration between Eisai and BioArctic for AD

Since 2005, BioArctic has had a long-term collaboration with Eisai regarding the development and commercialization of drugs for the treatment of AD. The commercialization agreement on the lecanemab antibody was signed in December 2007, and the development and commercialization agreement on the antibody lecanemab back-up for AD was signed in May 2015. Eisai is responsible for the clinical development, application for market approval and commercialization of the products for AD. BioArctic has no development costs for lecanemab in AD.