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Study of BAN2401 (lecanemab) in people with early stage Alzheimer's disease to evaluate its effectiveness in preventing disease progression

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial focuses on studying Preclinical Alzheimer's Disease in people who have different levels of brain amyloid buildup. The study tests a medication called lecanemab (also known as BAN2401), which is given through intravenous infusion. During the study, some participants will also receive imaging tests using two special substances: [18F]NAV4694 and [18F]MK-6240, which help visualize changes in the brain.

The main purpose is to determine if lecanemab works better than placebo in people who are in the early stages of Alzheimer's disease but have not yet developed symptoms. The study consists of two parts: one for people with high levels of amyloid in the brain (A45 Trial) and another for those with intermediate levels (A3 Trial). The treatment period lasts for 216 weeks, which is about four years.

During the study, participants will receive regular doses of either lecanemab or placebo through an IV line. They will also undergo brain imaging tests called PET scans that use special tracking substances to measure the amount of amyloid and another protein called tau in their brains. The study includes regular memory and thinking tests to track any changes in brain function over time. After the main study period, participants may have the option to continue in an extension phase of the trial.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial screening

    Your eligibility will be assessed through several tests, including memory assessments and brain imaging.

    A plasma biomarker test will be performed to check brain amyloid levels.

    Your cognitive function will be evaluated using tests including the Mini Mental State Examination (MMSE) and Memory Scale.

  2. Step 2

    Assignment to trial group

    Based on your amyloid levels, you will be assigned to either the A45 trial (elevated amyloid) or A3 trial (intermediate amyloid).

    You will be randomly assigned to receive either lecanemab or a placebo through intravenous infusion.

  3. Step 3

    Treatment period

    The treatment will continue for 216 weeks (approximately 4 years).

    Regular brain scans will be performed at weeks 96 and 216 to monitor changes in amyloid and tau proteins.

    Your memory and cognitive function will be regularly assessed throughout the study.

    A study partner (family member or friend) will need to maintain regular contact with you to provide information about your daily activities.

  4. Step 4

    Extension phase

    After completing the main study period, you may be eligible to continue in an extension phase.

    The extension phase will focus on evaluating the long-term safety of the treatment.

    Continued participation of your study partner will be required during this phase.

Who can join the trial?

9 criteria

  • Age between 55 to 80 years at the time of consent. People aged 55-64 must have at least one of these risk factors: - A close family member (parent, sibling) diagnosed with dementia before age 75 - Having at least one APOE4 gene variant - Previously confirmed elevated brain amyloid through testing
  • Must have a plasma biomarker test showing intermediate or elevated brain amyloid levels, or previous test results confirming these levels
  • Score of 0 on the Clinical Dementia Rating (CDR) scale, which measures cognitive and functional performance
  • Score of 27 or higher on the Mini Mental State Examination (MMSE), with adjustments based on education: - 25 or higher for 12 years or less of education - 26 or higher for 13-15 years of education - 27 or higher for 16+ years of education
  • Score of 6 or higher on the Wechsler Memory Scale-Revised Logical Memory test, which evaluates memory function
  • Must have specific levels of brain amyloid as measured by PET scan: - Above 40 centiloids for A45 Trial - Between 20-40 centiloids for A3 Trial
  • Must have a study partner who: - Has weekly contact with the participant - Can provide information about the participant's daily activities - Is willing to participate in the study
  • Must provide written informed consent
  • Must be willing and able to follow all study requirements

Who cannot join the trial?

14 criteria

  • History of brain disorders including stroke (blocked or bleeding blood vessels in the brain), seizures (fits), or brain tumors
  • Current diagnosis of any significant psychiatric disorder (mental health condition requiring treatment)
  • History of alcohol or substance abuse within the past 5 years
  • Presence of any medical conditions that could interfere with brain scan procedures
  • Previous participation in other clinical trials involving experimental medications within 6 months
  • Known allergies to study medication components
  • Significant heart, liver, or kidney disease
  • Uncontrolled high blood pressure
  • Active cancer or cancer treatment within the last 5 years
  • Blood clotting disorders or regular use of blood-thinning medications
  • Pregnancy, breastfeeding, or planning to become pregnant during the study
  • Unable to undergo MRI (magnetic resonance imaging) scans due to metal implants or claustrophobia (fear of confined spaces)
  • Severe vision or hearing problems that could interfere with cognitive testing
  • Regular use of medications that could affect memory or thinking abilities
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Investigated drugs

BAN2401 (lecanemab) is an investigational medication designed to target and remove beta-amyloid proteins from the brain. It belongs to a class of drugs called monoclonal antibodies. This medication works by binding to and clearing out harmful amyloid protein deposits that are thought to contribute to the development of Alzheimer's disease. It is administered through intravenous infusion and is being studied for its potential to slow down or prevent the progression of Alzheimer's disease in people who have early signs or are at risk of developing the condition.

What is already known about the treatment

BAN2401 - An investigational monoclonal antibody administered through intravenous infusion, designed to target and remove beta-amyloid plaques in the brain for the treatment of preclinical Alzheimer's Disease. This medication is currently being studied in clinical trials to evaluate its effectiveness in patients with elevated and intermediate amyloid levels, focusing on its ability to slow cognitive decline and reduce brain amyloid accumulation. BAN2401 works by selectively binding to and eliminating toxic beta-amyloid aggregates, which are believed to contribute to the progression of Alzheimer's disease, and belongs to the class of disease-modifying anti-amyloid therapies.

Investigated diseases

  • Preclinical Alzheimer's Disease

    A phase that occurs before the clinical symptoms of Alzheimer's disease become apparent. During this stage, changes begin to occur in the brain, particularly the accumulation of amyloid protein, but individuals remain cognitively normal. This condition involves gradual biological changes that can start many years before noticeable memory problems develop. People in this stage maintain their ability to perform daily activities and may not show any obvious signs of cognitive decline.

  • Early Preclinical Alzheimer's Disease

    The earliest detectable stage of Alzheimer's disease progression, characterized by subtle brain changes and intermediate levels of amyloid protein accumulation. During this phase, individuals maintain normal cognitive function and independence in daily activities. The brain undergoes early biological changes, though these changes are not yet severe enough to cause noticeable symptoms. This stage represents a crucial period where disease processes have begun but have not yet impacted cognitive abilities.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-510888-39-00Protocol codeBAN2401-G000-303Estimated enrolment1 400 patientsSponsorEisai Limited

sourced from the EU Clinical Trials Register and site verification

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