With this supplement, we request support to expand the NIH INCLUDE Trial-Ready Cohort-Down Syndrome (TRC-DS) project, which as part of the R61 phase (cohort) seeks to enroll 120 participants with DS, in advance of the R33 phase placebocontrolled clinical trial of an anti-amyloid therapeutic in this population. The specific aims of the TRC-DS project include building a readiness cohort that will both inform the design of a clinical trial as well as provide interested and eligible participants while collecting a rich set of participant-level phenotypic data. The Institute Jérôme Lejeune is a preeminent center in the world for clinical care of individuals with DS, including older adults with DS-related AD. Adding this site to the ACTC-DS network for participation in the TRC-DS project will further advance the impact and diversity of the project and establish a strong collaboration with an outstanding research team.

AD remains one of our greatest unmet medical needs, without any approved disease-modifying therapies. Individuals with Down Syndrome (DS) comprise the largest group with genetically determined AD. We propose to add the Institute Jérôme Lejeune to the ACTC-DS network for participation in the TRC-DS project.