The only drug approved by the Food and Drug Administration (FDA) to treat moderate to severe Alzheimer's disease (AD), memantine (Namenda) has shown a clear benefit for patients taking it in combination with donepezil, a cholinesterase inhibitor. In a randomized, double-blind, placebo-controlled clinical trial, researchers studied over 300 patients with moderate to severe AD receiving stable doses of donepezil plus either memantine or a placebo. Those in the memantine group had significantly better outcomes on measures of cognition, activities of daily living, global outcome (overall function), and behavior.
Approved by the FDA late last year, memantine is the first of a new class of drugs for AD. Because of its unique mechanism of action, it represents a new approach to treatment of late-stage AD.