Drug Development.

Area of Science:

• Neurology
• Immunotherapy
• Clinical Research

Background:

• Lecanemab, an anti-amyloid monoclonal antibody, has shown promise in early Alzheimer's disease (AD).
• Previous trials indicated reduced amyloid markers and slowed cognitive decline over 18 months.
• Long-term benefits were observed in open-label extension studies.

Purpose of the Study:

• To evaluate the real-world, long-term safety and efficacy of lecanemab in early AD patients.
• To assess patient and care partner perspectives on lecanemab therapy.
• To compare real-world outcomes with findings from clinical trials.

Main Methods:

• A single-center, retrospective case series of 136 early AD patients treated with lecanemab.
• Data collected included baseline characteristics, treatment exposure, efficacy, and safety.
• Patient and care partner experiences were evaluated using a telephone survey based on "What Matters Most" concepts.

Main Results:

• 42 patients received lecanemab for ≥3 years, with 14 receiving ≥5 years.
• Continuous amyloid reduction and delayed time-to-progression were observed over 4 years.
• No new safety signals emerged; adverse events, including ARIA, were consistent with known profiles.
• Patients and care partners reported stabilized disease, slowed progression, and improved quality of life.

Conclusions:

• Long-term lecanemab treatment in a real-world setting mirrors clinical trial safety and efficacy.
• Continued lecanemab therapy beyond trials supports meaningful delays in disease progression.
• Most trial participants opted for long-term lecanemab, reporting life extension and improvement benefits.