Lecanemab Treatment in a Specialty Memory Clinic

Area of Science:

• Neurology
• Pharmacology
• Clinical Medicine

Background:

• Two monoclonal antibodies, lecanemab and donanemab, targeting amyloid plaques are FDA-approved for early symptomatic Alzheimer disease (AD).
• Significant adverse events include infusion-related reactions and amyloid-related imaging abnormalities (ARIA), encompassing edema/effusion (ARIA-E) and hemorrhage/hemosiderin deposition (ARIA-H).
• The clinical practice feasibility and safety of these treatments remain unclear.

Purpose of the Study:

• To assess the feasibility and safety of administering lecanemab in a specialty memory clinic setting.
• To evaluate the incidence and management of adverse events associated with lecanemab treatment in early symptomatic AD patients.

Main Methods:

• Retrospective analysis of 234 consecutive patients initiated on lecanemab between August 2023 and October 2024.
• Patients received lecanemab 10 mg/kg intravenously every two weeks.
• Assessment of infusion-related reactions, ARIA development (ARIA-E and ARIA-H), and treatment withdrawal.

Main Results:

• Infusion-related reactions occurred in 37% of patients and were typically mild.
• Over an average of 6.5 months, 22% of patients developed ARIA (15% ARIA-E, 6.7% ARIA-H).
• Symptomatic ARIA occurred in 5.7% of patients, with 1.0% experiencing severe symptoms; no macrohemorrhages or deaths were reported. Patients with mild dementia had a higher rate of symptomatic ARIA (27%) compared to those with mild cognitive impairment (1.8%).
• Treatment withdrawal occurred in 9.8% of patients, with 4.3% due to ARIA.

Conclusions:

• Initiating lecanemab treatment in a specialty memory clinic setting demonstrated manageable safety and feasibility.
• The observed rates of adverse events, particularly ARIA, suggest that these therapies can be safely administered in clinical practice.
• Findings support further discussion on the risk-benefit profile of anti-amyloid therapies for Alzheimer disease.