Alzheimer's disease (AD) is an age-related degenerative disorder of the brain, characterized by progressive decline in cognitive function and ability to perform activities of daily living, and ultimately can lead to death due to complications of the disease. AD is thought to be caused by an excess of A-Beta amyloid, a sticky protein in the brain that forms amyloid plaques. Treatments that slow the synthesis or deposition of A-Beta amyloid, or that increase clearance, might be expected to slow the progression of AD.