Evan Dewey, a 42-year-old man with Down syndrome, has been participating in a study at Vanderbilt University Medical Center in Nashville for over a year. The ABATE study aims to develop a vaccine to prevent or slow the progression of Alzheimer's disease, which is the leading cause of death in people with Down Syndrome over the age of 35. Dewey is the only participant in the Southeast who has qualified for the study. During his trips, he has regular blood draws, MRIs and PET scans, and physical and neurological testing. The study is still open and researchers are seeking more participants.