Phase 3 IGIV, 10% in Alzheimer´s Disease

Inclusion Criteria: * Males or females of age 50 to 89 years inclusive at the time of screening * Written informed consent obtained from either the subject or the subject's legally authorized representative prior to any study-related procedures * Written informed consent obtained from an able and competent caregiver who is willing to comply with the requirements of the protocol pertaining to him/her, including facilitating the subject's participation in the study * Diagnosis of Probable Alzheimer´s Disease (AD) according to NINCDS-ADRDA\* 1984 criteria (\* National Institute of Neurological and Communicative Disorders and Stroke - Alzheimer's Disease and Related Disorders Association) * Dementia of mild to moderate severity (Mini-Mental State Examination \[MMSE\] 16-26 inclusive at the time of screening) * Neuroimaging (computed tomography \[CT\] or MRI) performed after symptom onset consistent with AD diagnosis * Willingness to comply with the requirements of the protocol and ability to comply with testing and infusion regimen, including adequate corrected visual acuity and hearing ability * For at least 12 weeks prior to screening, on stable doses of AD medication(s) approved by local regulatory authorities. Subjects must not be on two acetylcholinesterase inhibitors concurrently. * Venous access for repeated infusion and phlebotomy * If receiving psychoactive medications (eg, antidepressants other than monoamine oxidase inhibitors \[MAOIs\] and most tricyclics, antipsycho…