Ionis Pharmaceuticals discontinued development of an investigational Alzheimer’s therapy targeted to people with Down syndrome, according to company statements reported by Endpoints News. The move removes an early‑stage candidate from a population at high genetic risk for Alzheimer’s due to trisomy 21 and underscores the tough risk‑reward calculus for neurodegeneration programs in niche populations. Ionis confirmed the decision internally; the termination joins a string of pipeline reprioritisations across biotech where limited signals or strategic shifts prompt program wind‑downs.