The primary objective of this study is to investigate the safety and efficacy of simufilam (PTI-125) in enhancing cognition and slowing cognitive and functional decline following 52-week, repeat-dose oral administration in participants with mild-to-moderate AD. Secondary objectives include the assessment of simufilam's effect on neuropsychiatric symptoms and caregiver burden. A third objective is to investigate the effect of simufilam treatment on plasma biomarkers. A limited number of research sites will be invited to participate in the pharmacokinetic (PK) and plasma biomarker sub-study. Collection of PK samples will enable an exposure-response analysis. Approximately 100 subjects will participate (50 per group). Plasma samples will be collected during the Screening Visit and again at Weeks 28 and 52. Change from Baseline for plasma biomarkers represent additional secondary endpoints.~Safety will be evaluated by adverse event monitoring, vital signs, clinical labs, and the Columbia Suicide Severity Rating Scale at every visit. Subjects will undergo magnetic resonance imaging (MRI) during screening to ensure entry criteria are met (unless recent MRI confirms entry criteria). Resting electrocardiograms will be conducted at Baseline (Study Day 1) and Weeks 4, 28, and 52. A complete physical and neurological examination will be performed at screening, and brief examinations will be performed at all other visits. Weight will be measured during the Screening Period, at Baseline (Study Day 1), and at all other visits.~An independent Data Safety Monitoring Board (DSMB) will meet periodically to review subject safety assessments and determine if dosing may continue. A charter will be developed with specific guidance for the DSMB.
A 52-week safety and efficacy study of simufilam (PTI-125) given twice daily to participants with mild-to-moderate Alzheimer's disease (AD) for 52 weeks. Approximately 750 participants will be randomized (1:1) to receive either placebo or 100 mg tablets of simufilam, twice daily, for 52 weeks. Clinic visits will occur 4 weeks after the baseline visit, and then every 12 weeks until the end of the study. The safety of simufilam, and its efficacy in enhancing cognition and slowing cognitive and functional decline will be evaluated.