Evaluation of E2609 in Subjects With Mild Cognitive Impairment or Mild Dementia Due to Alzheimer's Disease (Study: E2609-A001-101 Amendment 02)

Study Overview
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Brief Summary
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Subjects will be adults aged 50 to 85 years who have subjective memory complaints and mild cognitive impairment or mild dementia due to Alzheimer's disease (AD). Subjects taking thyroxine or thyroid supplements and subjects receiving an acetylcholinesterase inhibitor (AChEI) and/or memantine for AD must be on a stable dose for at least 12 weeks prior to Screening and remain on their stable dose throughout the trial. Subjects will receive placebo or a single oral dose of E2609. Safety assessments will be conducted. Additionally, the pharmacokinetics of E2609 and drug effects will be evaluated using cerebrospinal fluid biomarkers and cognitive and psychological measures.

Official Title
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A Randomized, Double-blind, Placebo-controlled Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Single Oral Doses of E2609 in Subjects With Mild Cognitive Impairment or Mild Dementia Due to Alzheimer's Disease

Conditions
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Alzheimer's Disease

Intervention / Treatment
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* Drug: E2609
* Drug: Placebo for E2609


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Meets the current cognitive classification of MCI or mild dementia due to AD pathology (all subjects having a positive biomarker for amyloid β) as defined by the National Institute on Aging - Alzheimer's Association (NIA-AA) research criteria Aged 50 to 85 years, inclusive at time of consent Exclusion criteria: Currently has any neurological condition other than AD (Alzheimer's disease)-related that could be contributing to the subject's cognitive impairment Significant pathological findings on brain MRI at Screening, including but not limited to multiple microhemorrhages Any psychiatric diagnosis or symptoms, e.g., hallucinations, major depression,anxiety or delusions that in the Investigator's opinion could interfere with assessment of cognition or confound the diagnosis of MCI or mild dementia due to AD in the subject. A lifetime history of cerebrovascular events or non-vasovagal related loss of consciousness within the last 10 years Any other abnormality of the ECG at Screening and/or Baseline (including QRS > 110 ms, abnormal electrical axis, PR interval > 220 ms and conduction abnormalities) considered clinically significant by the investigator History of cardiac arrhythmias, ischemic heart disease or cerebrovascular disease Lower spinal malformation on physical or lumbar spine radiography, local spinal infection, or other abnormality, including but not limited to obesity, that would prevent LP or insertion of an indwelling catheter for CSF sampling Any history of seizure disorder, symptomatic seizures (not including a history of simple febrile seizures in childhood) or any past or present medical condition which, in the opinion of the investigator has the potential to reduce seizure threshold (e.g., history of head trauma or concussion, previous alcohol abuse, substance abuse).

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: E2609<br> | Drug: E2609<br>* E2609 capsules: 5 mg, 25 mg, 50 mg, and 200 mg E2609 doses: 5 mg, 10 mg, 25 mg, 50 mg, 100 mg, 200 mg, and 400 mg According to the randomized study design, participants who are assigned to receive E2609 will each receive a single assigned dose consisting of two capsules of E2609 or in some cases one capsule of E2609 and one of placebo<br>|
| Placebo Comparator: Placebo for E2609<br> | Drug: Placebo for E2609<br>* Placebo capsules According to the randomized study design, participants who are assigned to receive placebo will each receive a single dose consisting of two capsules of placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent change from baseline in cerebrospinal fluid amyloid-beta levels |  | baseline to 36 hours post-dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of adverse events |  | 8 days |