The study was terminated after completing the dose escalation portion of the study. The expansion cohort was not initiated to conduct a global trial based on the approved US IND using a new manufacturing process.

The purpose of this study is to evaluate the safety, tolerability, and preliminary efficacy of SNK01 (autologous natural killer cell), as a single agent, for the treatment of subjects with Alzheimer's disease.

Inclusion Criteria:

• Capable of giving signed informed consent which includes compliance with the requirements and restrictions listed in the informed consent form and protocol. If the subject is incapable of giving or signing informed consent, the subject must have a legally authorized representative willing to consent on their behalf.
• Subject must be ≥ 55 to 85 years old at the time of consent.
• Magnetic resonance imaging (MRI) scans of the brain within the past six months reveal evidence and findings consistent with Alzheimer's disease, including hippocampal volume loss and/or overall cerebral atrophy (cerebral volume loss).
• Fluorodeoxyglucose-positron emission tomography (FDG-PET) scans of the brain within the past six months reveal evidence and findings consistent with mild cognitive impairment or Alzheimer's disease.
• Subject presenting, during evaluation by the study Investigator, to have spontaneous memory loss or presenting abnormal memory function in early screening.
• Subject must be in good health with adequate hearing and vision.
• Subject must have a reliable caregiver.
• Women of childbearing potential who are not abstinent and intend to be sexually active with a nonsterilized male partner must be willing to use an adequate method of contraception throughout the study and for one month following the last day of the last administration of final study drug dose. Acceptable methods include hormonal contraception (oral contraceptives [taken 90 days prior to administration of study drug], intrauterine devices (IUD), or double barrier methods (e.g., vaginal diaphragm/vaginal sponge plus condoms, or condom plus spermicidal jelly), sexual abstinence, or a vasectomized partner.

Exclusion Criteria:

• Any medical or neurological conditions, other than Alzheimer's disease, that could contribute to the cause of cognitive impairment in the subject. Examples include, but are not limited to, frontotemporal dementia (FTD), Lewy body dementia, vascular dementia, Parkinson's disease, corticobasal degeneration, Creutzfeldt-Jakob disease, progressive supranuclear palsy, Huntington's disease, normal pressure hydrocephalus, seizure disorders or cerebral hypoxia, post-traumatic stress disorder (PTSD), or alcohol or medication use or abuse.
• Subject does not present with signs of mild cognitive impairment or Alzheimer's disease at screening, or during evaluation by the study Investigator.
• Subject presents with significant brain disease including hemorrhage or infarction.
• Subject has a history of cerebrovascular accident or transient ischemic attack (TIA), or unexplainable loss of consciousness during the past year.
• Subject has a history of schizophrenia, schizoaffective disorder, major depressive disorder (MDD), bipolar disorder, or any other clinically relevant psychiatric disease.
• Subject has a history of seizure episodes within the past three years.
• Subject has uncontrolled diabetes mellitus.
• Subject has a history of unstable angina, myocardial infarction, chronic heart failure, or clinically relevant conduction abnormalities within the year prior to screening.
• Subject suffers from renal or hepatic failure.
• Subject is infected with the human immunodeficiency virus (HIV), Hepatitis B (Hep B), Hepatitis C (Hep C), or any other infection or active systemic disease.
• Subject is using anticoagulants (except aspirin at or below a prophylactic dose).
• Subject is currently exceeding the normal recommended dosage for any drug used to treat Alzheimer's disease (e.g., memantine or acetylcholinesterase inhibitors [AChEI]).
• Subject has contraindication to MRI scans, FDG-PET scans, or lumbar spinal taps.
• Subject whose safety is considered to be at risk from trial's intervention, as determined by the study Investigator.
• Pregnant or lactating female subjects.