• 19 Nov 2025
• Admin
• News Article

Eisai to Present New Lecanemab Data at CTAD 2025: Long-Term Benefits, Real-World Insights, and Subcutaneous Dosing

BioArctic and Eisai are heading to the CTAD 2025 conference in San Diego with a packed slate of new data on lecanemab (Leqembi). The presentations span long-term outcomes, safety, dosing innovations, real-world evidence, and deeper insights into the drug’s mechanism.

This matters. Lecanemab is one of the most closely watched Alzheimer’s treatments worldwide, and CTAD remains the biggest stage for clinical-trial breakthroughs in the field.

What Eisai Will Highlight at CTAD?

Eisai plans to share updates across five major themes.

1. Long-Term Treatment Benefits

New analyses will explore:

• How continued therapy may maintain or extend cognitive benefits
• Estimated time savings over 10 years of treatment
• Outcomes drawn from Phase 3 clinical data

Presentation times:

• Dec 2 at 5:05 PM PT
• Dec 3 at 2:40 PM PT

2. Subcutaneous Initiation Dosing

Early signals suggest subcutaneous dosing may offer new flexibility for patients.

A late-breaking symposium on Dec 3 (3:10–3:50 PM PT) will detail:

• Pharmacokinetics of subcutaneous initiation
• Potential workflow advantages for clinics
• Safety observations so far

This option could reduce infusion burden and improve access.

3. Real-World Experience

Insights from real-world practice are increasingly vital.

CTAD will include:

• Interim findings from a post-marketing study in Japan
• Data from the US ALZ-NET registry, including safety and baseline characteristics
• A New England center’s report on clinical and patient-reported outcomes

These updates will help clinicians understand how lecanemab performs outside controlled trials.

4. Mechanism and Biomarker Data

A dedicated session will cover the effects of lecanemab on soluble amyloid-beta protofibrils.

Why this matters:

• Protofibrils are considered highly toxic Aβ species
• They disrupt neuron signaling and contribute to cognitive decline
• Lowering protofibrils may protect neurons and slow disease progression

The session is scheduled for Dec 2 at 1:40 PM PT.

5. Poster Sessions at CTAD

Several posters will expand the evidence base around lecanemab. Highlights include:

• Enrollment patterns in preclinical AD trials
• Stability and improvement trends in early AD
• Long-term benefit estimates for low-amyloid patients
• Acceptability of autoinjector-based subcutaneous dosing
• Comparisons of ARIA risk between lecanemab and donanemab
• Binding profiles across amyloid-beta species
• Modelled long-term outcomes using QSP frameworks
• Cost and efficiency differences between IV and subcutaneous routes

This broad range shows how lecanemab’s evidence base continues to expand.

The BioArctic–Eisai Collaboration: A Quick Refresher

Lecanemab originated from BioArctic’s research based on the Arctic mutation, discovered by Professor Lars Lannfelt. The collaboration has evolved over two decades and now covers:

• Discovery and early research
• Global clinical development led by Eisai
• Shared commercialization in the Nordic region
• Milestone-based financial frameworks for BioArctic

This alliance has shaped one of the most important Alzheimer’s programs in the world.

Lecanemab Today: Approvals, Formulations, and Ongoing Studies

Lecanemab is approved in 51 countries, with ongoing regulatory reviews in several more.

Key facts:

• Standard treatment begins with IV infusions every two weeks for 18 months
• Maintenance dosing shifts to once every four weeks in several major markets
• The US also has an approved subcutaneous autoinjector for maintenance
• A rolling FDA submission for subcutaneous initiation dosing began in September 2025

Ongoing studies include:

• AHEAD 3-45, testing lecanemab in preclinical AD
• Tau NexGen, evaluating the drug in dominantly inherited AD
• Several mechanistic and long-term modelling efforts

These programs aim to move treatment earlier in the disease and refine dosing.

About BioArctic

BioArctic is a Swedish biopharma company focused on neurodegenerative diseases.
The company:

• Invented Leqembi, the first drug proven to slow early Alzheimer’s disease
• Maintains research programs in Parkinson’s, ALS, and Alzheimer’s
• Uses its BrainTransporter technology to improve drug delivery across the blood-brain barrier
• Is listed on Nasdaq Stockholm Large Cap

Why This Matters?

Alzheimer’s research is shifting from symptom management to disease modification.
Lecanemab sits at the center of this shift, and each new dataset helps clarify:

• Who benefits most
• How early treatment should begin
• Whether newer dosing routes can reduce burden
• How real-world patients respond over time

CTAD 2025 is set to move that conversation forward.