A Study to Evaluate Safety, Tolerability, and Efficacy of BAN2401 in Subjects With Early Alzheimer's Disease

Key Inclusion criteria for Mild Cognitive Impairment due to Alzheimer's Disease

- intermediate likelihood:

1. Subjects who meet the National Institute of Aging - Alzheimer's Association (NIA-AA) core clinical criteria for mild cognitive impairment due to Alzheimer's disease - intermediate likelihood
2. Subjects who have a CDR score of 0.5 and a Memory Box score of 0.5 or greater at Screening and Baseline
3. Subjects who report a history of subjective memory decline with gradual onset and slow progression over the last one year before Screening; MUST be corroborated by an informant
4. Subjects with objective impairment in episodic memory as indicated by 1-1.5 standard deviations below age-adjusted mean in the WMS-IV

Key Inclusion criteria for Mild Alzheimer's Dementia:

1. Subjects who meet the NIA-AA core clinical criteria for probable Alzheimer's Disease
2. Subjects who have a CDR score of 0.5-1.0 and a Memory Box score of 0.5 or greater at Screening and Baseline

Inclusion criteria that must be met by all subjects:

1. Positive amyloid load as indicated by PET assessment
2. Age between 50 and 90 years, inclusive
3. MMSE score equal to or greater than 22, and equal to or less than 30, at Screening and Baseline
4. BMI less than 35 at Screening
5. Females must not be pregnant or lactating, and specified contraceptive precautions must be followed
6. Subjects on acetylcholinesterase inhibitor or memantine therapy for Alzheimer's disease must be on a stable dose for at least 12 weeks prior to baseline
7. Subjects must have identified caregivers/informants
8. Subjects must provide written informed consent.

Key Exclusion criteria:

1. Any neurological condition that may be contributing to cognitive impairment above and beyond that caused by the subject's AD
2. History of transient ischemic attacks (TIA), stroke, or seizures within 12 months of Screening
3. Any psychiatric diagnosis or symptoms, (e.g., hallucinations, major depression, or delusions) that could interfere with study procedures in the subject
4. . Contraindications to MRI scanning, including cardiac pacemaker/ defibrillator, ferromagnetic metal implants, e,g., in skull and cardiac devices other than those approved as safe for use in MR scanners
5. Evidence of other clinically significant lesions that could indicate a dementia diagnosis other than AD on brain MRI at Screening, or other significant pathological findings on brain MRI at Screening
6. A prolonged QT/QTc interval (QTc > 450 ms) as demonstrated by a repeated electrocardiogram (ECG)
7. Certain other specified medical conditions
8. Severe visual or hearing impairment that would prevent the subject from performing psychometric tests accurately