A Study to Verify the Clinical Benefit of Aducanumab in Participants With Early Alzheimer's Disease

Inclusion Criteria

• •The participant must have confirmed amyloid beta pathology by cerebrospinal fluid (CSF) or amyloid PET
• •Must have a history of subjective memory decline with gradual onset and slow progression over the 6 months before Screening, confirmed by study partner
• •The participant must have 1 informant/care partner who, in the Investigator's opinion, has frequent and sufficient contact with the participant (at least 10 hours/week in person or by phone) as to be able to provide accurate information about the participant's cognitive and functional abilities over time
• •Must meet all of the following clinical criteria for MCI due to Alzheimer's disease or mild Alzheimer's disease according to National Institute on Aging and Alzheimer's Association (NIA-AA) criteria
• •1. Have an MMSE score between 22 and 30 inclusive
• •2. Have a CDR memory score \>0.5
• •3. Have a Clinical Dementia Rating Scale Global Score (CDR-GS) of 0.5 or 1.0
• •4. Have a Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) score of 85 or lower indicative of objective cognitive impairment
• •Apart from a clinical diagnosis of early Alzheimer's disease, the participant must be in good health as determined by the Investigator based on medical history and screening assessments
• •Must consent to apolipoprotein E (ApoE) genotyping. (Note: Participants are not required to be ApoE ε4 carriers)
• •A negative PET scan result with any amyloid-targeting ligand within 12 months prior to Screening