This study evaluates the effects of Ginkgo biloba on blood biomarkers related to Alzheimer's disease in patients with mild cognitive impairment. Participants will be randomly assigned to receive either Ginkgo biloba or a placebo for 6 months. Changes in blood biomarkers, including p-tau217 and neurofilament light (NfL), as well as cognitive function, will be assessed to determine whether Ginkgo biloba may influence disease-related biological processes.

Ginkgo biloba has been widely used for cognitive impairment and is suggested to exert neuroprotective effects through antioxidant, anti-inflammatory, and anti-amyloid mechanisms. However, its effects on Alzheimer's disease-related blood biomarkers remain unclear. Alzheimer's disease is characterized by amyloid and tau pathology, which can be partially reflected by plasma p-tau217, while neurofilament light (NfL) reflects neuroaxonal injury.

This is a multicenter, randomized, double-blind, placebo-controlled study conducted in patients with mild cognitive impairment due to Alzheimer's disease. Participants will be assigned in a 1:1 ratio to receive either Ginkgo biloba 240 mg or placebo once daily for 6 months.

The study aims to evaluate whether Ginkgo biloba administration affects these blood biomarkers (p-tau217, NfL) and whether changes in biomarkers are associated with cognitive outcomes measured by the Clinical Dementia Rating-Sum of Boxes (CDR-SB). By analyzing these relationships, this research seeks to explore the potential disease-modifying effects of Ginkgo biloba.

Inclusion Criteria:

• Age 20 years or older
• Clinical Dementia Rating (CDR) score of 0.5
• Patients clinically indicated for treatment with Ginkgo biloba extract

Exclusion Criteria:

• Current use of cholinesterase inhibitors such as donepezil, rivastigmine, or galantamine.
• Refusal to provide informed consent.
• Presence of neurological or psychiatric conditions other than Alzheimer's disease that may affect cognitive function.
• Known hypersensitivity to Ginkgo biloba extract or any of its components.
• Pregnant women.
• Genetic conditions associated with lactose intolerance, including galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption.
• Presence of bleeding disorders at screening, or requirement for continuous use of medications that may affect study drug efficacy (e.g., anticoagulants, antiplatelets, thrombolytics, peripheral vasodilators, PGE1 and its derivatives).
• Any condition that, in the opinion of the investigator or study staff, makes the participant unsuitable for the study or unable to comply with study procedures.

There is no plan to share individual participant data to protect the privacy of study participants and comply with institutional data protection policies.