Protocol Amendment PA01: To allow re-screening of patients, changes of eligibility criteria and to provide clarifications where needed. Major Changes: Safety Follow-up visit window: this was defined as up to 7 days for patients who withdrew. Visits taking place over 2 consecutive days: it was clarified that IMP had to be dispensed on the second day, after all assessments were performed. Drop-out Retrieval Visit: it was clarified that only new SAEs which were considered as possibly/probably related to IMP by the investigator were to be reported. Screening period: it was clarified that this need not necessarily be a 2-week period, but that it could be up to 2 weeks. Safety follow-up of patients who withdraw consent: it was clarified that such patients had to have a safety follow-up visit, but that the visit was only to be recorded in the medical records. Exclusion criterion 17: it was clarified that patients with pacemakers were eligible provided they followed a routine check-up with their doctor and were considered stable. Exclusion criterion 28: the exclusion criteria for heart rate and the duration of the PR interval were revised. Re-screening: the possibility of re-screening patients, who failed screening due to certain treatable medical conditions, but who were otherwise eligible was added. MMSE: it was clarified that at the Screening visit, this was to be performed prior to any of the other assessments, including ADAS-Cog. SAEs: it was added that under no circumstance were investigators to report SAEs to Lundbeck beyond 24 hours. Concomitant medication: clarifications on the use of other investigational drugs, selected anticonvulsants, and trazodone were provided.