Study of SPG302 in Adult Participants With Mild-to-Moderate Alzheimer's Disease (AD)

This phase 2 study will evaluate the safety, tolerability, clinical efficacy, pharmacokinetics, and pharmacodynamics of SPG302 in adult participants with mild-to-moderate AD.

This is a phase 2, multicenter study to assess the safety, tolerability, CNS effects, pharmacokinetics, pharmacodynamics and clinical efficacy of SPG302 in adult participants with mild-to-moderate AD. The study will consist of 2 parts: Part A: Placebo-controlled, randomized, safety and preliminary efficacy cohort with daily dosing for 28 day cycles Part B: a randomized expansion cohort of daily dosing for 28 day cycles

Inclusion Criteria: * Age 45-85 * Diagnosis of mild to moderate AD * Clinical laboratory values within normal range or \< 1.5 times ULN * If receiving AD-specific treatment, have been on stable dose for ≥ 3 months prior to first dose of study drug. * Life expectancy of \>2 years * Able and willing to provide written informed consent Exclusion Criteria: * Any physical or psychological condition that prohibits study completion * Known cardiac disease * Active or history of malignancy in the past 5 years * Serious infection that will not be resolved by first day of study intervention. * History of clinically significant CNS event or diagnosis in the past 5 years. * Acute illness within 30 days of Day 1 * History of suicidal behavior or suicidal ideation * History of chronic alcohol use or substance abuse in the last 5 years * HIV, hepatitis B and/or hepatitis C positive * Vaccines within 14 days * Receipt of investigational products within 30 days * Blood donation within 30 days * Pregnant or breastfeeding