[Clinical trials in Alzheimer disease. Comments on the project of FDA's guidelines]

The draft guidelines for the clinical evaluation of antidementia drugs give an important series of advice on all trials phases: the main objective, in the present state of knowledge, is to improve memory. patients must have a confirmed dementia, and other causes than Alzheimer diseases must be excluded by appropriate investigations. They should not be too severely ill, but they should be institutionalized, at least during the first phase of treatment, the placebo controlled trial and the dose-effect relationship are necessary, the cross-over trial is not advised, the treatment duration should be at least 3 to 6 months, two strictly independent evaluations are necessary: cognitive tests, and clinical global impression based only on interviews of the patient, the file must contains at least 1000 cases with at least 300 cases treated 3-6 months with at least the median dose.