["alzheimer's disease"]
['s47445 5mg', 's47445 15mg', 's47445 50mg', 'placebo']

        Inclusion Criteria:

          -  Out-patients

          -  Able to perform neuropsychological tests

          -  Have a responsible informant

          -  DSM-IV-TR criteria for Dementia of the Alzheimer's Disease Type

          -  Mini mental State Examination (MMSE) = 15-24 both inclusive

          -  National Institute of Mental Health (NIMH) provisional criteria for depression in AD
             (NIMH-dAD)

          -  Cornell Scale for Depression in Dementia total score > or = 8

          -  Patients who have never been treated with AD treatments or patients who have stopped
             AD treatment whatever the reason

          -  Patients either not currently treated with an antidepressant or patients being treated
             with an antidepressant at the recommended dose for at least 8 weeks without clinical
             efficacy, who can stop this treatment according to the investigator's opinion.

        Exclusion Criteria:

          -  Patients not able to read or write

          -  Patients having participated in a study testing disease modifying therapy for AD, or
             in another study with administration of investigational drug or device within the
             previous 3 months prior to selection visit

          -  Depressive symptoms that, in investigator's judgment, are clearly due to a medical
             condition other than AD, or are a direct result of non-mood related dementia symptoms

          -  History of epilepsy or solitary seizure

          -  Medical history of Major Depressive Disorder more than 3 years before onset of the
             disease, treated with antidepressive drugs or electroconvulsive therapy

          -  Severe or unstable disease of any type that could interfere with safety and efficacy
             assessments

          -  Alcohol abuse or drug abuse or addiction, as judged by the clinician (excluding
             nicotine)

          -  Clinically relevant lactose intolerance

          -  Antidepressant treatment not stopped for at least 3 weeks before inclusion

          -  Significant worsening of depressive symptoms or high suicidal risk according to
             investigator's judgment

          -  For optional extension phase: medically instable Chronic Obstructive Pulmonary Disease
             and asthma, known hypersensitivity to donepezil hydrochloride or piperidine
             derivatives
      