Real-World Study Confirms Safety and Efficacy of Alzheimer’s Drug Lecanemab

As new anti-amyloid Alzheimer’s treatments move from tightly controlled clinical trials into everyday medical practice, a real-world study published in Neurology Open Access reveals that approximately 80% of patients can safely remain on lecanemab for at least one year with close clinical monitoring. Conducted by researchers at Duke Health and tracking patients treated between 2023 and 2025, the findings address pressing safety questions regarding treatment persistence, cognitive outcomes, and the management of cerebral side effects.

Real-World Treatment Persistence and Side Effect Profiles

The study followed more than 230 patients diagnosed with early Alzheimer’s disease or mild memory impairment who received lecanemab infusions at Duke Health. Researchers tracked side effects, serial MRI scans, and cognitive testing results up to 396 days post-infusion. According to the data, 79% of patients who initiated the protocol successfully continued therapy, while the 21% who discontinued did so primarily due to adverse events.

Among the tracked cohorts, about one in four patients, or 24.3%, developed Amyloid Related Imaging Abnormalities, commonly known as ARIA, which involves brain swelling or bleeding. As noted by Andrew (Andy) Liu, associate professor in the departments of neurology and pathology at Duke University School of Medicine and corresponding author of the study, fear surrounding brain swelling and bleeding has heavily influenced patient hesitation. However, Liu emphasized that most treatment-related side effects resolve over time without requiring additional medications or hospitalizations.

The investigation further established that patients possessing a high-risk Alzheimer’s gene variant—specifically APOE ε4 homozygotes—faced a roughly fourfold increase in susceptibility to ARIA. Chronologically, ARIA events manifested across an extended window, continuing up to 30 weeks post-infusion with distinct incidence peaks occurring around 10 weeks and 25 weeks. Beyond vascular imaging shifts, a significant minority of participants, standing at 31%, encountered serious adverse events. These events frequently included infusion reactions, falls, or strokes, though researchers noted that some incidents stemmed from the patient’s other illnesses rather than direct drug toxicity.

Diagnostic Challenges and Biomarker Research

Predicting which patients will experience vascular complications remains a primary hurdle in neurodegenerative care. The Duke team evaluated seven commonly available clinical, blood, and imaging diagnostic methods to determine their predictive value for ARIA. While individual or combined tests could not yet reliably forecast adverse events, researchers identified that a specific MRI measure of vascular changes paired with blood levels of the biomarker pTau/AB42 held the most promise for isolating low-risk patient profiles.

Cerebral amyloid angiopathy was identified as a core underlying mechanism by P. Murali Doraiswamy, a Duke professor in the departments of psychiatry and behavioral sciences and medicine as well as a study coauthor. Over half of all Alzheimer’s sufferers exhibit this condition—marked by the silent buildup of amyloid within the brain’s blood vessels—which Doraiswamy noted is also considered a contributing process behind ARIA.

To fortify safety protocols, Duke Health piloted an artificial intelligence-supported imaging tool designed to catch subtle ARIA manifestations earlier and more consistently during routine brain scans. With the institution having administered lecanemab to over 400 patients, positioning it among the most experienced centers in the country for anti-amyloid therapies, Liu manages a specialized biorepository. Storing blood and cerebrospinal fluid samples from treated individuals, this repository aims to accelerate the discovery of robust prognostic biomarkers for both cerebral amyloid angiopathy and ARIA.

Individualized Clinical Decision-Making and Patient Impact

Because lecanemab does not reverse symptoms or cure the underlying pathology, clinicians stress that slowing progression can help patients maintain independence longer. Heather Whitson, study coauthor and codirector of the Duke & UNC Alzheimer’s Disease Research Center, stated that the choice to pursue these medications requires highly individualized risk-benefit evaluations.

For patients like 74-year-old Sally Osmer, who received an early-stage diagnosis at Duke Health supported by genetic and imaging evaluations, the therapy offers extended stability. Having completed more than a year of infusions without serious adverse reactions, Osmer reported maintaining her daily routines and engagement with family. For patients navigating these complex treatment pathways, consulting with specialists or coordinating diagnostic evaluations remains essential for managing infusion schedules and serial MRI monitoring.

Funding for Liu’s research roles was supported by the Ann B. Bussel Award and a Duke-UNC NIH award, with several study authors disclosing professional relationships with various pharmaceutical entities, including the manufacturer of lecanemab. As clinical teams refine predictive diagnostics, the overarching aim remains pragmatic. As Liu summarized, the intervention is about buying time in a disease that takes it away.

Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider regarding any medical condition, diagnosis, or treatment plan.