A new study by Washington University School of Medicine in St. Louis confirms that the Alzheimer’s drug lecanemab is safe and manageable for patients, showing promise for broader use.
An Alzheimer’s therapy, lecanemab, was initially met with excitement when the FDA approved it in 2023 for its ability to modestly slow the progression of Alzheimer’s disease. Interest waned somewhat when side effects like brain swelling and bleeding emerged during clinical trials. Now, a new study by Washington University School of Medicine in St. Louis offers fresh hope by demonstrating that the drug is well-tolerated in real-world clinical settings, offering a safer path forward for many patients.
In a retrospective study published May 12 in JAMA Neurology, researchers analyzed the outcomes of 234 patients with very mild or mild Alzheimer’s disease who received lecanemab infusions at the Memory Diagnostic Center at WashU Medicine, a clinic specializing in treating patients with dementia.
The results were promising: severe side effects occurred in just 1% of patients, who required hospitalization. The most significant complications were rare and manageable.
“This new class of medications for early symptomatic Alzheimer’s is the only approved treatment that influences disease progression,” co-senior author Barbara Joy Snider, a professor of neurology, said in a news release. “But fear surrounding the drug’s potential side effects can lead to treatment delays. Our study shows that WashU Medicine’s outpatient clinic has the infrastructure and expertise to safely administer and care for patients on lecanemab, including the few who may experience severe side effects, leading the way for more clinics to safely administer the drug to patients.”
Snider led the lecanemab clinical trials at WashU Medicine.
Lecanemab is known to work by clearing amyloid plaque proteins, potentially extending independent living by about 10 months for patients. Because amyloid buildup marks the beginning of Alzheimer’s, the drug is recommended for people at the early stages of the disease.
Interestingly, the study found that only 1.8% of patients with very mild symptoms developed any adverse symptoms from the treatment, compared to 27% of patients with mild symptoms.
“Patients with the very mildest symptoms of Alzheimer’s will likely have the greatest benefit and the least risk of adverse events from treatment,” Snider added. “Hesitation and avoidance can lead patients to delay treatment, which in turn increases the risk of side effects. We hope the results help reframe the conversations between physicians and patients about the medication’s risks.”
One of the main reasons for hesitation regarding lecanemab is a side effect known as amyloid-related imaging abnormalities, or ARIA.
ARIA, which manifests as brain swelling or bleeding, affected 12.6% of participants in clinical trials, though most cases were asymptomatic and resolved on their own. Only a small percentage — approximately 2.8% — experienced symptoms such as headaches, confusion, nausea and dizziness, with deaths linked to lecanemab occurring in about 0.2% of treated patients.
Patients at the Memory Diagnostic Center have been receiving lecanemab since 2023, with doses administered bi-weekly. WashU Medicine doctors closely monitor these patients, using advanced imaging techniques to detect any signs of ARIA early. If ARIA symptoms appear, the treatment is discontinued, and severe cases are managed with steroids in the hospital.
“Most patients on lecanemab tolerate the drug well,” added co-senior author Suzanne Schindler, an associate professor of neurology. “This report may help patients and providers better understand the risks of treatment, which are lower in patients with very mild symptoms of Alzheimer’s.”
Source: Washington University School of Medicine in St. Louis