Brief Summary:

An urgent need exists to find effective treatments for Alzheimer's disease (AD) that can arrest or reverse the disease at its earliest stages. The emotional and financial burden of AD to patients, family members, and society is enormous, and is predicted to grow exponentially as the median population age increases. Current FDA-approved therapies are modestly effective at best. This study will examine a novel therapeutic approach using intranasal insulin (INI) that has shown promise in short-term clinical trials. If successful, information gained from the study has the potential to move INI forward rapidly as a therapy for AD. The study will also provide evidence for the mechanisms through which INI may produce benefits by examining key cerebral spinal fluid (CSF) biomarkers and hippocampal/entorhinal atrophy. These results will have considerable clinical and scientific significance, and provide therapeutically-relevant knowledge about insulin's effects on AD pathophysiology. Growing evidence has shown that insulin carries out multiple functions in the brain, and that insulin dysregulation may contribute to AD pathogenesis.

This study will examine the effects of intranasally-administered insulin on cognition, entorhinal cortex and hippocampal atrophy, and cerebrospinal fluid (CSF) biomarkers in amnestic mild cognitive impairment (aMCI) or mild AD. It is hypothesized that after 12 months of treatment with INI compared to placebo, subjects will improve performance on a global measure of cognition, on a memory composite and on daily function. In addition to the examination of CSF biomarkers and hippocampal and entorhinal atrophy, the study aims to examine whether baseline AD biomarker profile, gender, or Apolipoprotein epsilon 4 (APOE-ε4) allele carriage predict treatment response.

In this study, 240 people with aMCI or AD will be given either INI or placebo for 12 months, following an open-label period of 6 months where all participants will be given active drug. The study uses insulin as a therapeutic agent and intranasal administration focusing on nose to brain transport as a mode of delivery.