Safety and Efficacy of L. Lactis CKDB001 in Subjects With Early Alzheimer's Disease

Inclusion Criteria: 1. Male and female adults aged ≥55 and ≤85 years at the time of written consent 2. Subjects with a Korean Mini-Mental State Examination (K-MMSE) score of 20 to 28 3. Have a global Clinical Dementia Rating (CDR) score of 0.5 to 1 and a CDR Memory Box score of 0.5 or greater 4. Subjects who test positive for amyloid on Positron Emission Tomography (PET) Exclusion Criteria: 1. Subjects with clinically significant diseases other than Alzheimer's disease that may confound cognitive assessment * History of central nervous system (CNS) diseases * Active central nervous system (CNS) infection capable of affecting cognitive function, or a history of infection resulting in neurological sequelae * Structural brain abnormalities identified on screening MRI that could account for cognitive impairment * Abnormal thyroid function identified at screening * Vitamin B12 deficiency identified at screening 2. History of seizure disorder or epilepsy 3. History or suspicion of alcohol or substance abuse/dependence 4. History of psychiatric disorders, including schizophrenia, bipolar disorder, or clinically significant major depressive disorder, with current active symptoms 5. History of malignancy diagnosed or recurrent within 5 years prior to screening 6. History of a major cardiovascular event within 12 months prior to screening 7. Cardiovascular disease requiring the administration of anticoagulants 8. Severe or active infectious disease requiring treatment with antibiotics or antivirals within 4 weeks prior to randomization, or expected to require such treatment during the study period 9. Clinically significant gastrointestinal disorders within 3 months prior to screening, or conditions that may lead to malabsorption 10. Treatment with any disease-modifying therapy for Alzheimer's disease within 1 year prior to screening 11. Initiation or dosage/regimen changes of symptomatic treatments for dementia within 12 weeks prior to screening 12. Chronic use of medications acting on the CNS or those that may affect cognitive function within 8 weeks prior to screening 13. Regular use of medications that may alter the gut microbiota within 4 weeks prior to screening