Evaluate the Safety and Efficacy of AD-35 Tablet in Subjects With Mild to Moderate Alzheimer's Disease

In this multicenter, randomized, double blind, parallel-group, placebo controlled phase II study, 240 patients with mild to moderate Alzheimer's Disease are planned to be enrolled and randomly assigned 1:1:1 to receive placebo, or different doses of AD-35 tablet (30 or 60 mg). After the first 26 weeks, subjects on active study drug will remain on the current doses, and subjects assigned to placebo will be randomized to receive 30 mg and 60 mg AD-35 tablet in a 1:1 ratio, respectively, for the second 26 weeks. This study will evaluate the safety, preliminary efficacy and pharmacokinetics of AD-35 tablets in patients with mild to moderate Alzheimer's Disease.