Therapeutic trials in Alzheimer's disease.

Therapeutic trials activity in Alzheimer's disease increased during the past year, with both the initiation of new and the continuation of ongoing symptomatic treatment studies designed to demonstrate enhancement of cognitive abilities. Interest in interventions for noncognitive or behavioral symptoms has also increased. Attempts to convert new basic scientific discoveries into clinical approaches that slow the progression of the disease also generated enthusiasm. Timely consideration of certain critical methodological, ethical, and policy issues are likely to enhance this late phase activity in drug development in the years to come.