Recent clinical findings published in Neurology Open Access demonstrate that approximately 80% of early-stage Alzheimer’s patients treated with the anti-amyloid therapy lecanemab remained on the medication for at least one year. Conducted by researchers at Duke Health, the study tracks real-world safety outcomes, management of brain swelling risks, and treatment persistence outside of strictly controlled clinical trials.
As anti-amyloid therapies transition from controlled clinical trials into everyday medical practice, patients and clinicians face critical questions regarding safety, treatment duration, and real-world efficacy. Lecanemab, an FDA-approved therapy, targets and clears a protein linked to Alzheimer’s disease from the brain. While clinical trials established its baseline efficacy in slowing cognitive decline, real-world data provide a clearer picture of how these treatments perform across diverse patient populations under standard clinical care.
In Plain English: The Clinical Takeaway
- Real-World Retention: Roughly 79% to 80% of patients successfully maintain their lecanemab infusion schedule past the one-year mark, showing that everyday clinical management matches trial persistence rates.
- Managing ARIA: Amyloid Related Imaging Abnormalities—specifically localized brain swelling or microhemorrhages—occur in about 24% of patients, but most cases resolve without hospitalization.
- Genetic Risk Factors: Individuals possessing a specific high‑risk Alzheimer’s gene (APOE ε4 homozygotes) faced roughly a fourfold greater chance of developing ARIA.
Real-World Safety and ARIA Monitoring in Clinical Practice
The study tracked over 230 patients diagnosed with early Alzheimer’s disease or mild memory impairment who received lecanemab at Duke Health between 2023 and 2025. Researchers utilized specialized MRI sequences to monitor for small areas of bleeding in the brain and edema. The primary safety concern associated with anti-amyloid treatments remains Amyloid Related Imaging Abnormalities, commonly abbreviated as ARIA.
According to the findings, 24.3% of the cohort developed ARIA during treatment. The data revealed two distinct temporal peaks for these imaging anomalies—roughly at 10 weeks and 25 weeks after initiating therapy—with events continuing up to 30 weeks. This timeline highlights the clinical necessity for serial MRI monitoring well into the treatment course. Among the 21% of patients who discontinued the medication, adverse events served as the primary driver.
“There’s been a lot of fear about this medication, especially around brain swelling and bleeding,” notes Andrew (Andy) Liu, associate professor in the departments of neurology and pathology at Duke University School of Medicine. “What we found is that, in the real world, with careful selection and close monitoring, approximately 80% of patients are able to remain on lecanemab for at least one year. Importantly, most treatment-related side effects resolve over time without the need for additional medications or hospitalizations.”
Predictive Biomarkers and Advanced AI Integration
Identifying which patients carry the highest risk for adverse neurological events remains a core challenge. The Duke team evaluated seven commonly available clinical, blood, and imaging tests to determine their predictive value for ARIA. While no single test provided absolute certainty, an MRI measure evaluating vascular changes combined with blood levels of the biomarker pTau/AB42 demonstrated the highest predictive potential for identifying low-risk subjects.
Underlying vascular conditions heavily influence these safety profiles. Cerebral amyloid angiopathy (CAA)—defined as a condition involving the silent accumulation of amyloid protein within the brain’s blood vessels—occurs in more than 50% of all Alzheimer’s patients and serves as a core anatomical factor believed to drive ARIA development. To address this, Duke Health researchers piloted an artificial intelligence (AI) imaging tool designed to detect subtle ARIA alterations on brain scans earlier and with greater consistency.
| Metric / Observation | Clinical Percentage / Finding |
|---|---|
| 1-Year Treatment Retention Rate | ~79% to 80% of patients maintained therapy |
| Incidence of ARIA (Brain Swelling/Bleeding) | 24.3% of total study cohort |
| APOE ε4 Homozygote ARIA Risk Multiplier | Approximately 4x higher risk compared to non-carriers |
| Discontinuation Rate Due to Adverse Events | 21% of patients |
| Prevalence of Concurrent Serious Adverse Events | 31% (including infusion reactions, falls, or strokes, often confounded by comorbid illnesses) |
Funding for Andrew Liu’s role in the research was provided by the Ann B. Bussel Award and the Duke-UNC NIH award, with one or more study authors disclosing professional relationships with pharmaceutical entities, including the manufacturer of lecanemab. Meanwhile, institutional expansion continues; Duke Health has administered lecanemab to more than 400 patients, establishing a comprehensive biorepository of blood and cerebrospinal fluid to refine future predictive biomarkers.
Consulting a Doctor
Treatment decisions should always be made in direct consultation with a qualified medical professional. The decision of whether or not these new medications are right for a patient is highly individualized.
References
- Duke Health. Real-world safety and treatment persistence of lecanemab in early Alzheimer’s disease. Neurology Open Access.
Disclaimer: This article is for informational purposes only and does not substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or qualified health provider with any questions regarding a medical condition.
