NMDA-enhancing Agent for Treatment of Mild Cognitive Impairment and Mild Alzheimer's Disease

NMDA activation plays an important role in learning and memory. NMDA receptors were found to decrease in the frontal lobe and hippocampus of Alzheimer\'s disease and mild cognitive function impairment. This study is a randomized, double-blind, placebo-controlled drug trial. All patients will be allocated randomly to 2 groups: (1) NMDA enhancer: DAOI-B group (starting dose: 250-500 mg/d); (2) placebo group. The study period is 24 weeks. The investigators hypothesize that DAOI-B may yield better efficacy than placebo for cognitive function in patients with mild cognitive impairment or mild Alzheimer\'s disease.