Clinical Trials

Inclusion Criteria:

• Meets National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS/ADRDA) criteria for probable AD
• Has a Modified Hachinski Ischemia Scale score of less than or equal to 4
• Has a Mini-Mental State Examination (MMSE) score of 20 through 26 at Screening visit
• Has a Geriatric Depression Scale score of less than or equal to 6 (on the staff-administered short form)
• Has had a magnetic resonance imaging (MRI) or computerized tomography (CT) scan performed within the past 2 years that has confirmed no findings inconsistent with a diagnosis of AD
• Has a florbetapir positron emission tomography (PET) scan or cerebrospinal fluid (CSF) result consistent with the presence of amyloid pathology at screening

Exclusion Criteria:

• Does not have a reliable caregiver who is in frequent contact with the participant (defined as at least 10 hours per week), will accompany the participant to the office and/or be available by telephone at designated times, and will monitor administration of prescribed medications
• Meets National Institute of Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS/AIREN) criteria for vascular dementia
• Has current serious or unstable illnesses including cardiovascular, hepatic, renal, gastroenterologic, respiratory, endocrinologic, neurologic (other than AD), psychiatric, immunologic, or hematologic disease and other conditions that, in the investigator's opinion, could interfere with the analyses of safety and efficacy in this study; or has a life expectancy of <2 years
• Has had a history within the last 5 years of a serious infectious disease affecting the brain or head trauma resulting in protracted loss of consciousness
• Has a history within the last 5 years of a primary or recurrent malignant disease with the exception of resected cutaneous squamous cell carcinoma in situ, basal cell carcinoma, cervical carcinoma in situ, or in situ prostate cancer with a normal prostate-specific antigen posttreatment
• Has a known history of human immunodeficiency virus (HIV), clinically significant multiple or severe drug allergies, or severe posttreatment hypersensitivity reactions
• Has received acetylcholinesterase inhibitor (AChEIs), memantine and/or other AD therapy for less than 4 months or has less than 2 months of stable therapy on these treatments
• Has received medications that affect the central nervous system (CNS), except treatments for AD, for less than 4 weeks
• Has a history of chronic alcohol or drug abuse/dependence within the past 5 years