Condition: Alzheimer Disease

The purpose of this study is to assess the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of MK-2214 in adults with mild cognitive impairment (MCI) or mild-to-moderate Alzheimer’s Disease (AD). The primary hypothesis (Part 1) is that at a generally well tolerated dose level, the true geometric mean concentration at Day 85 of MK-2214 in cerebrospinal fluid is >0.3 nanomolar (nM). Optional healthy older participants (Part 2) may receive MK-2214 at dose levels determined by criteria met in Part 1.