The Promise and Challenges of Treating Alzheimer’s Disease in People with Down Syndrome

Individuals with Down syndrome are at a higher risk of developing Alzheimer’s disease at a younger age, with studies showing that by age 40, their brains already exhibit amyloid plaques. Despite this increased vulnerability, people with Down syndrome have often been left out of or inadequately represented in clinical trials for Alzheimer’s disease treatments.

Recently, lecanemab, a drug that targets and removes beta-amyloid plaques, received approval from the U.S. Food and Drug Administration for early-stage Alzheimer’s disease treatment. A groundbreaking study led by researchers at Brigham and Women’s Hospital and the University of California, Irvine explored the potential of lecanemab in targeting amyloid plaques in individuals with Down syndrome. The results of the study, published in JAMA Neurology, revealed that the drug effectively bound to amyloid in all 15 samples tested. However, researchers also noted that lecanemab showed a tendency to bind to brain blood vessels, raising concerns about its safety.

Co-corresponding author Lei Liu, MD, PhD, from Brigham and Women’s Hospital, emphasized the significance of the study, stating, “Our research focuses on the use of lecanemab, a recently approved therapy for Alzheimer’s disease, in individuals with Down syndrome.” Co-corresponding author Elizabeth Head, PhD, from the University of California, Irvine, highlighted the potential benefits of anti-amyloid drugs for individuals with Down syndrome while underlining the importance of cautious safety considerations, particularly regarding the risk of hemorrhagic complications.

The research team examined brain tissue samples from 15 individuals with Down syndrome aged between 43 and 68 years. While the study was limited in its sample size and age range, the researchers aim to expand their research to include samples from younger brain donors to explore potential age-related factors in the drug’s binding to blood vessels. Additionally, future investigations will involve evaluating lecanemab’s binding profile in individuals with late-onset Alzheimer’s disease to determine if similar patterns emerge.

Throughout their study, the research team expressed their gratitude to individuals with Down syndrome who generously donated their brains for research purposes, emphasizing the crucial role of participants in advancing our understanding of Alzheimer’s disease and its treatment in vulnerable populations.

As researchers continue to explore the potential of lecanemab and other anti-amyloid drugs for treating Alzheimer’s disease in individuals with Down syndrome, they acknowledge the need for ongoing vigilance in monitoring safety concerns and adapting treatment approaches to ensure the well-being of patients. Through collaborative efforts between healthcare providers, researchers, and individuals with Down syndrome and their families, strides can be made in improving the quality of life and care for those affected by Alzheimer’s disease and related conditions.