Current treatment of mild cognitive impairment and Alzheimer's disease.

Current therapy for Alzheimer's disease (AD) consists of two classes of drugs: the cholinesterase inhibitors, of which there are three currently available medications; and the glutamate modulators, of which there is one. There has been no new information regarding efficacy of the cholinesterase inhibitors or memantine in AD over the past year, but a large, randomized trial concerning mild cognitive impairment was reported. Donepezil delayed conversion to dementia for 12 months but not longer in that trial, whereas vitamin E had no impact on outcomes. The results of the first immunization therapy for AD were released in 2005. Adverse events forced the premature discontinuation of the trial, but there were some grounds for optimism about the basic approach. Several new agents targeted directly at amyloid beta peptide production are currently in clinical trials, but no large studies have been reported over the past year.