Efficacy and Safety of LY451395 in Patients With Probable Alzheimer's Disease

Inclusion Criteria: * Must have a clinical diagnosis of Alzheimer's Disease * Must be at least 50 years of age * Must fluently read and speak English * Must have a reliable caregiver Exclusion Criteria: * Has serious health problems other than Alzheimer's Disease * Cannot swallow whole pills * Has had a menstrual period in the last two years * Takes insulin for diabetes * Has taken Aricept, Reminyl, or Exelon in the last 5 weeks