Inclusion Criteria:  Signed informed consent from subject (or legally authorized representative, LAR) and study partner. Male or female, age 50 to 90 inclusive. Have a study partner who is able to accompany the subject, has frequent contact with subject. Meet criteria for Alzheimer's Disease by NIAA-AA criteria. Must speak English fluently. Must have education of at least 8 years. Must have adequate hearing and visual abilities. MMSE score of 14 to 28. Clinical Dementia Rating (CDR) Global score of 0.5 to 2.0 inclusive. Absence of suicidal ideation for at least 1 year. Absence of medical conditions that could affect ability to participate in study. MRI within 1 year of screening, not showing clinically significant structural lesions. Subjects without available MRI within 1 year, must have an MRI performed for eligibility. Stable neuropsychiatric medications for at least 2 months prior to screening. If female, must not be of childbearing potential, as defined by being postmenopausal (more than 1 year without periods) or surgically sterile for at least 6 months prior to screening. If male, must agree to use contraception if with a potentially childbearing partner.  Exclusion Criteria:  Presence of clinically significant disorders of the central nervous system other than Alzheimer's disease, such as Lewy Body Disease, Parkinson's disease, hydrocephalus, epilepsy, demyelinating disease, brain tumors, or psychiatric disorders (such as schizophrenia, or severe affective disorders). Serious or unstable hematologic, hepatic, renal, pulmonary, cardiac, or other medical disease. Chronic hepatitis B or C infection, indicated by positive HBSAg, or HCV-Ab with HCV RNA presence. Known history of human immunodeficiency virus (HIV) infection. Known immune disorder that has a history of requiring treatment with immunosuppressive drugs within the past 1 year. Have a drug or alcohol abuse within 12 months prior to screening. Clinically significant laboratory abnormalities at screening. Screening ECG showing repeated QTcF > 480 msec, or other clinically significant abnormalities. Clinically significant structural brain abnormalities, such as hydrocephalus or intra-axial brain tumors. Participation in another investigational study within 30 days or 5 half-lives prior to screening, whichever is greater. Participation in another study that would have cognitive testing during the duration of this study. No history of Covid19 or viral infections within 3 months. Have a clinically significant medical, surgical, laboratory, or behavioral abnormality, which in the judgment of the Investigator makes the subject unsuitable for the study.