To Evaluate Safety, Tolerability and Pharmacological Effects of PU AD in Subjects With Mild AD Dementia

This is a multicenter, randomized, double blind, placebo controlled, parallel group Phase 2A study with one active dose of PU AD and matching placebo, once daily (qd), designed to assess safety, tolerability and pharmacological effects of oral PU AD (dihydrochloride salt) in subjects with mild AD. This study will be performed at up to 50 clinical sites in the US and approximately 150 subjects are expected to participate in this study, with 75 subjects in each treatment arm randomized 1:1. Subjects with mild AD meeting all inclusion criteria and none of the exclusion criteria are eligible to participate in this study. The study consists of a Screening Period (including Pre treatment) (4 weeks), Treatment Period (24 weeks), and a safety Follow up visit (within 30 days \[±7 days\] after the last dose of IMP). The expected study duration is 24 Months. The Screening Visit and Pre treatment Visit will take place within 4 weeks of dosing to assess eligibility of subjects. Enrolled subjects will return to the site for randomization and baseline assessments at Week 1. Subjects will be randomized with a 1:1 ratio to one of two treatment arms: 30 mg PU AD or matching 30 mg placebo qd. During the 24 Week Treatment Period, subjects will be administered 30 mg PU AD or matching 30 mg placebo qd, orally. According to investigator's clinical judgement, subjects experiencing intolerable AEs, if medically necessary, may be allowed to adjust the dose regimen from 30 mg qd to 30 mg every other day (qod), with approval by the medical monitor. If patients still cannot tolerate the adjusted dose regimen, the investigator must discuss early termination with the medical monitor. Subjects will return to the site at Week 2, Week 4, Week 6, Week 12, Week 18, and Week 24 for study assessments as specified PK sampling time points are specified in and will support a population PK model. . Any subject who discontinues prior to completion of the study, and reached 12 weeks of treatment should have all scheduled assessments of the Week 24/Early Termination (ET) Visit completed. All subjects will return to the site for a Follow up Visit, within 30 days (±7 days) after the last dose of study for safety assessments at the Week 28/End of Study (EoS) Visit