Clinical Trials

Inclusion Criteria:

• Meets National Institute on Aging/Alzheimer's Association (NIAAA) core clinical criteria for probable AD dementia or prodromal AD (consistent with the NIAAA diagnostic criteria and guidelines for mild cognitive impairment [MCI]).
• Evidence of the AD pathological process, as confirmed by CSF or amyloid PET scan.
• Demonstrated abnormal memory function.
• MMSE score great than or equal to 22 (≥ 22).
• Clinical dementia rating-global score (CDR-GS) of 0.5 or 1.0. 
• Availability of a reliable study partner who accepts to participate in study procedures throughout the 2 years duration of study.
• If receiving symptomatic AD medications, the dosing regimen must have been stable for 3 months prior to baseline and until randomization. 
• For enrollment in the China extension, patients must have residence in mainland China, Hong Kong, or Taiwan and be of Chinese ancestry.

Exclusion Criteria: 

• Any evidence of a condition other than AD that may affect cognition.
• History of schizophrenia, schizoaffective disorder, major depression, or bipolar disorder.
• History or presence of clinically evident systemic vascular disease that in the opinion of the investigator has the potential to affect cognitive function.
• History or presence of clinically evident cerebrovascular disease.
• At risk for suicide in the opinion of the investigator.
• Patients with evidence of folic acid deficiency.
• Alcohol and/or substance abuse or dependants in past 2 years.
• Relevant brain hemorrhage, bleeding disorder and cerebrovascular abnormalities.
• Any contraindications to brain MRI.
• Unstable or clinically significant cardiovascular, kidney or liver disease. 
• Uncontrolled hypertension.