Recent work suggests that modulation of brain cholesterol and its derivatives might be a beneficial therapeutic approach for treating Alzheimer’s Disease. In particular, we have created stem cell versions of human Alzheimer’s Disease “in a dish”, and also used mouse models of Alzheimer’s Disease pathology to show that a drug approved for use in AIDS treatment, called efavirenz, significantly alters several biochemical changes typical of Alzheimer’s Disease.  In addition, our preliminary work and published work suggests strongly that efavirenz should be used at low doses, but not high doses typical of AIDS treatment. We now propose to test efavirenz in a Phase 1 trial in early Alzheimer patients for safety and predicted changes in brain cholesterol turnover and biomarkers of the disease. Positive results will lead to testing for beneficial effects on Alzheimer’s Disease in Phase 2 clinical trials.