The FDA-approved cancer drug bexarotene effectively restores cognitive function and memory within days in mice with a genetically engineered form of Alzheimer’s disease, neuroscientists report (Science, DOI: 10.1126/science.1217697). Gary Landreth, director of the Alzheimer Research Laboratory at Case Western Reserve University, and colleagues report that treatment with bexarotene clears mouse brains not only of diffuse excess amyloid-β protein but also of plaques of deposited amyloid-β, both of which are hallmarks of the disease. Within 72 hours, areas of plaque had decreased by more than 50%; plaque areas were reduced by 75% after 14 days of treatment. The mice were also able to again perform tasks that they had lost the ability to do, such as nesting. The drug stimulates retinoid X receptors, which in turn help stimulate the production of the protein ApoE, which is crucial for clearing the brain of excess amyloid-β. Although the results are tantalizing, the effectiveness of the drug as a treatment in humans is still unclear, the researchers note.