Pilot Study to Investigate the Safety and Feasibility of AntiRetroviral Therapy for Alzheimer's Disease

This open label study of 3TC will collect initial proof-of-concept data on 3TC target engagement, CNS penetration, efficacy and safety in older adults with early stage Alzheimer's disease. If successful, data will be used to design a larger phase 2 clinical trial. The investigators aim to I) Quantify 3TC target engagement and CNS penetration, II) Determine if 3TC suppresses Alzheimer's disease-relevant outcomes, and III) Assess the safety and tolerability of 3TC in older individuals with early Alzheimer's disease. The study will consist of a screening/baseline period of 30 days pre-treatment, a 24-week open label treatment period, and a follow up visit one month following treatment. Visits to the clinic include a pre-treatment screening visit that includes a comprehensive neuropsychological exam, a tablet-based neuropsychological exam, and a blood draw. For eligible participants, a lumbar puncture will be performed on day one of treatment. Participants will visit the clinic on day one of treatment and at weeks 8, 16, and 24 of treatment to complete medication checks, physical examinations, tablet-based cognitive screening, and blood draw. At week 24 of treatment, patients will undergo a post-treatment comprehensive neuropsychological exam, a lumbar puncture to collect cerebrospinal fluid, and a blood draw. One month after the final dose of medication, participants will return to the clinic for a final safety assessment and disenrollment.