Effects of Sirolimus on Asymptomatic ApoE4 Carriers

Alzheimer's disease is a devastating neurodegenerative disease characterized by accumulation of clumps (also called plaques) and bundles of fibers (also called tangles) in the brain, for which there is currently no cure. Sirolimus (Rapamycin) is an FDA-approved medication which may improve the blood flow to the brain. The purpose of the clinical trial is to find out whether sirolimus can help improve blood flow and energy use in the brain in women ages 45 to 65 who have the ApoE4 gene, a gene which increases the risk of developing Alzheimer's disease later in life. There will be two arms in this trail, a sirolimus arm and a placebo arm. A placebo is a pill that looks like the study drug, but it does not have any real medicine in it. Participants will be randomized to one arm or the other, but not to both arms. Three study visits over a 12-week period are required. Participants will: (i) Complete some questionnaires about how well you think; (ii) Complete genetic testing for the ApoE4 gene; (iii) Have blood work, blood pressure and height and weight collected; (iv) Take either Sirolimus or a placebo daily, by mouth, for approximately 4 weeks; (v) Keep a diary of when the sirolimus or placebo is taken; (vi) Complete 2 Magnetic Resonance Imaging (MRI) exams