Inclusion Criteria:

• Written informed consent (Informed consent #1) obtained before any assessment is performed, including consent to receive disclosure of their APOE genotype.
• Male or female, age 60 to 75 years inclusive, at the time of signing Informed consent #1:  
  • Once the cap of approximately 20% of total participants in the age group 60-64 years at time of signature of ICF#2 is met, a restriction to this age group will apply.
  • Note: the same age limitations of 60-75 years, inclusive is also applied at the time of signing Informed consent #2.
• Females must be considered post-menopausal and not of child bearing potential.  Confirmation will be obtained for those who continue on to the Screening Epoch.
• Mini-Mental State Examination (MMSE) total score ≥ 24 (can be based on documented result obtained within the previous 3 months).
• Psychological readiness to receive APOE genotype information based on predisclosure rating scales, specifically:
  • Geriatric Depression Scale (GDS) total score < 6.  If the score is between 6 and 10 (inclusive), the participant can only be included based on investigator’s judgment, with special attention given to the questions:
    • Item 3: “Do you feel your life is empty?”
    • Item 6: “Are you afraid that something bad is going to happen to you?”
    • Item 12: “Do you feel pretty worthless the way you are now?”
    • Item 14: “Do you feel your situation is hopeless?”
  • Six Item Subset Inventory of the STAI-AD total score <17.
  • If the score is between 17 and 19 (inclusive), the participant can only be included based on the investigator’s judgment.
• Participant is fluent in, and able to read, the language in which study assessments are administered (e.g. completion of at least 6 years of regular schooling or sustained employment).
• Participant’s willingness to have a study partner for the Screening and Treatment epoch (see Screening and Treatment Epoch Inclusion criteria #6 below).

Exclusion Criteria:

• Any disability that may prevent the participant from completing all study requirements (e.g., blindness or deafness that is not appropriate for age, severe language difficulty).
• Current medical or neurological condition that might impact cognition or performance on cognitive assessments e.g., MCI, dementia, Huntington’s disease, Parkinson’s disease, Lyme disease, schizophrenia, bipolar disorder, major depression, active seizure disorder, history of traumatic brain injury with loss of consciousness, alcohol/drug abuse or dependence currently, or dependence within the last two years.
• Advanced, severe progressive or unstable disease that may interfere with the safety, tolerability and study assessments, or put the participant at special risk, e.g. active hepatitis or HIV infection based on a positive lab result in the last 12 months for HBV/HCV and/or HIV), severe renal impairment, severe hepatic impairment, uncontrolled or significant cardiac disease including recent (within six months) myocardial infarction, congestive heart failure (New York Heart Association [NYHA] functional class III-IV), unstable angina, or long QT syndrome.
• History of malignancy of any organ system, treated or untreated, within the past 60 months, regardless of whether there is evidence of local recurrence or metastases. However, localized nonmalignant tumors not requiring systemic chemo- or radio-therapy, localized basal or squamous cell carcinoma of the skin, or in-situ cervical cancer are permitted.
• History of hypersensitivity to any of the investigational drugs or their excipients/adjuvant, or to drugs of similar chemical classes.
• Indication for or current treatment with ChEIs and/or another prescription AD treatment (e.g. memantine).
• Contraindication or intolerance to MRI or PET investigations (with fluorinated radioligands).

Exclusion Criteria:

• Any disability that may prevent the participants from completing all study requirements.
• Current medical or neurological condition that might impact cognition or performance on cognitive assessments.
• Advanced, severe progressive or unstable disease that may interfere with the safety, tolerability and study assessments, or put the participant at special risk.
• History of malignancy of any organ system, treated or untreated, within the past 60 months.
• History of hypersensitivity to any of the investigational drugs or their excipients / adjuvant or to drugs of similar chemical classes.
• Indication for, or current treatment with ChEIs and/or another AD treatment (e.g. memantine).
• Contraindication or intolerance to MRI or PET investigations (with fluorinated radio ligands).
• Brain MRI results showing findings unrelated to AD that, in the opinion of the Investigator might be a leading cause to cognitive decline, might pose a risk to the participant, or might prevent a satisfactory MRI assessment for safety monitoring.
• Suicidal Ideation in the past six months, or Suicidal Behavior in the past two years.
• A positive drug screen at Screening, if, in the Investigator's opinion, this is due to drug abuse.
• Significantly abnormal laboratory results at Screening, not as a result of a temporary condition.
• Current clinically significant ECG findings.

For Cohort - II only:

• Participants with depigmenting or hypopigmenting conditions (e.g. albinism vitiligo) or active / history of chronic urticarial in the past year.