To Evaluate Effects of AZD1446, Placebo and Donepezil in Patients With Alzheimer's Disease

A Phase II, Multi-center, Randomized, Double-blind, Placebo-controlled, Crossover Study to Evaluate the Pharmacodynamic Effect of Single and Multiple Oral Doses of AZD1446/ Placebo and a Single Dose of Donepezil on Quantified Electroencephalography and Event-Related Potentials in Patients With AD

The purpose of this study is to evaluate whether treatment with single and multiple oral doses of AZD1446 for 1 week will have effect on Quantified Electroencephalography and Event-Related Potentials in patients with Alzheimers Disease. The total treatment period is 9 weeks, divided into 5 equally long sub-periods of 7 days and 4 wash-out periods of 7 days each.

Inclusion Criteria:

• Clinical diagnosis of probable Alzheimer´s Disease
• Hachinski Ischaemic score < 4
• MSE score 18 to 24

Exclusion Criteria:

• History of any clinically significant disease or dementia other than Alzheimer´s Disease
• Current major depressive disorder or other major psychiatric disorders