A Study to Evaluate the Safety and Tolerability of SAGE-718 in Participants With Mild Cognitive Impairment or Mild Dementia Due to Alzheimer's Disease (AD)

Study Overview
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Brief Summary
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The primary purpose of this study is to evaluate the safety and tolerability of SAGE-718 and its effects on cognitive and neuropsychiatric symptoms in participants with mild cognitive impairment (MCI) or mild dementia due to Alzheimer's disease (AD).

Official Title
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An Open-Label Evaluation of the Safety and Tolerability of SAGE-718 in Participants With Mild Cognitive Impairment or Mild Dementia Due to Alzheimer's Disease

Conditions
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Alzheimer Disease, Cognitive Dysfunction, Mild Dementia

Intervention / Treatment
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* Drug: SAGE-718


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participant meets the following criteria for MCI or mild dementia due to AD at Screening: has a memory complaint, has clinical dementia rating (CDR) score of 0.5 to 1.0 (inclusive) with a memory box score ≥0.5, has essentially preserved activities of daily living Participant has a score of 15 to 24 (inclusive) on the Montreal Cognitive Assessment at Screening Participant has normal premorbid intelligence quotient (IQ) at Screening Participant has a study partner who is reliable, competent, at least 18 years of age, willing to be available to the study center by phone, support study-specific activities, and accompany the participant to study visits as needed Exclusion Criteria: Participant has any medical or neurological condition (other than AD) that might be contributing to the participant's cognitive impairment or history of cognitive decline Participant has a history of brain surgery, deep brain stimulation, a significant head injury causing loss of consciousness greater than 30 minutes, or hospitalization due to a brain injury Participant has a history, presence, and/or current evidence of a clinically-significant intracranial abnormality (eg, stroke, hemorrhage, space-occupying lesion) that could account for the observed cognitive impairment (excluding abnormalities consistent with underlying AD pathology) Participant has a history of possible or probable cerebral amyloid angiopathy, according to the Boston Criteria Participant has a history of seizures or epilepsy, with the exception of a single episode of febrile seizures in childhood Participant has current or recent suicidality

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 80 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SAGE-718<br>Participants will receive a single dose of SAGE-718 oral tablets, once daily in the morning for 14 days. | Drug: SAGE-718<br>* SAGE-718 oral tablets.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Treatment-Emergent Adverse Events (TEAE) | An adverse event (AE) is any untoward medical occurrence in a patient or clinical investigation participant administered a pharmaceutical product that does not necessarily have a causal relationship with this treatment. A TEAE is an AE that occurs after the first administration of a study drug. | Up to Day 28 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With Clinically Significant Changes in Vital Signs Measurements |  | Up to Day 28 | 
| Percentage of Participants With Clinically Significant Changes in Laboratory Assessments |  | Up to Day 28 | 
| Percentage of Participants With Clinically Significant Changes in Electrocardiogram (ECG) Measurements |  | Up to Day 28 | 
| Percentage of Participants With Change From Baseline Responses on the Columbia Suicide Severity Rating Scale (C-SSRS) | The C-SSRS scale consists of a baseline evaluation that assesses the lifetime experience of participants with suicidal ideation (SI) and suicidal behavior (SB) and a postbaseline evaluation that focuses on suicidality since the last study visit. The C-SSRS includes 'yes' or 'no' responses for assessment of suicidal ideation and behavior as well as numeric ratings for severity of ideation, if present (from 1 to 5, with 5 being the most severe). | Up to Day 28 |