The CIRCADIAN Study: Evaluation of Modulating Effect of Galantamine on Circadian Rhythm in Patients With Mild to Moderate Alzheimer's Disease

Inclusion Criteria: * Diagnosis of Alzheimer-type dementia according to the definition of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM IV-TR) and a diagnosis of possible or probable Alzheimer-type dementia, according to NINCDS-ADRDA classification (American Psychiatric Association, 2000 * McKhann, G. et al, 1984) * should have moderate dementia, evidenced by a Mini-Mental Status examination (MMSE) score between 12 and 20, including these limits * At inclusion, a recent CT or MRI must be available * Physical examination and the electrocardiogram (ECG) performed at the screening visit must be normal or consistent with the underlying illness in the study population * History of sleep behavior changes (eg: insomnia, daytime sleepiness, changes in sleep/wakefulness cycle) 2 or more weeks before, reported by the caregiver * Patients should have a caregiver sufficiently informed of their condition and, if possible, living with them * Patients (or their legally-acceptable representatives) must have signed an informed consent document indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study Exclusion Criteria: * History of other neurodegenerative disorders, such as Parkinson's disease, Pick disease or Huntington's chorea, Down syndrome, Creutzfeldt-Jakob disease (patients with mild extrapyramidal signs for which no treatment is required are not excluded from the trial) * Clinically significant cardiovascular disease expected to limit the ability of the patient to participate and complete the study * Any history of epilepsy or seizures (except for febrile seizures in childhood) * Clinically significant psychiatric condition, according to the DSM-IV criteria, particularly major depression or schizophrenia currently * Active peptic ulcer (treatment of the disease started \< 3 months or treatment is not successful * Clinically significant liver, renal, pulmonary, metabolic, or endocrine disorders * Clinically significant urinary flow obstruction * History of or suspected alcoholism or drug abuse in accordance to the DSM-IV criteria, in the past year, or previous history of prolonged abuse * Previous therapy with memantine or an acetylcholinesterase inhibitor (including galantamine) * Patients receiving antipsychotics, hypnotic or sedative agents (those patients who need this kind of medication during the study would be withdrawn from the study and replaced) * Bedridden patients