Alzheimer's Disease Long-term Follow-up Study (ALF Study)

Inclusion criteria

* Men or women aged 40 to 90 * Diagnosis of dementia according to DSM-IV * Diagnosis of probable AD as defined by NINCDS-ADRDA criteria * Mild to moderate AD at baseline, as defined by MMSE score of 10 to 26 * Patients were generally healthy and ambulatory or ambulatory aided * Patients did not take acetylcholinesterase inhibitor 4 weeks before screening * Patients have useful MRI results 3 months before screening Exclusion * If they have evidence of TIA or major infarction * Epilepsy patients * If they have evidence of other degenerative or psychiatric disorder, other serious disorder, alcoholism or drug abuse * If they sensitive to acetylcholinesterase * If they taken concomitant medication which were not allowed