News

The U.S. Food and Drug Administration (FDA) has approved the monthly maintenance dosing of Leqembi, an Alzheimer's drug developed by Japan-based Eisai (4523.T) in partnership with Biogen. This announcement marks a significant development in the treatment of Alzheimer's disease.

Background on Leqembi

Leqembi received standard U.S. approval in 2023 after clinical trials demonstrated that it could slow cognitive decline in patients suffering from Alzheimer's—a progressive brain-wasting disease. Despite its approval, the drug's uptake has been slow. This is partly due to its time-intensive administration requirements, which include regular intravenous infusions, frequent MRI scans, and health screenings to monitor patient safety.

New Dosing Options for Leqembi

Following the recent FDA approval, Leqembi patients now have new dosing options intended to improve convenience and adherence to their regimen.

Monthly Maintenance Dosing: One of the key features of the new regimen is the Monthly Maintenance Dosing option. After completing a rigorous treatment period of 18 months, during which patients received biweekly intravenous infusions, they can now switch to a monthly schedule. This change significantly reduces the frequency of clinic visits and the overall burden associated with the treatment.

• Transition Process: Patients will be monitored closely during the initial treatment phase, and once they have completed the biweekly infusions, they can opt for the monthly maintenance dose. This allows for a more manageable routine while still benefiting from the drug's therapeutic effects.

Biweekly Option: For those who prefer to maintain a more frequent treatment schedule, Leqembi will still be available on a biweekly basis. Patients can opt to continue receiving the drug every two weeks instead of transitioning to monthly dosing.

• Flexibility: This option is particularly beneficial for patients who may feel more comfortable with the regularity of biweekly treatments, providing them with the choice to tailor their therapy to their personal preferences and health needs.

How Leqembi Works

Leqembi is designed to target and clear amyloid beta, a sticky protein that builds up in the brains of Alzheimer's patients and is considered a hallmark of the disease. The drug is administered via intravenous infusion at specialized infusion centers, with each session lasting approximately one hour.

Ensuring Efficacy and Flexibility

Both dosing options are designed with the goal of maximizing patient flexibility without compromising the efficacy of the treatment. According to a joint statement from Eisai and Biogen, comprehensive modeling simulations of trial data indicate that the monthly maintenance dosing will be as effective in delivering therapeutic benefits as the original biweekly schedule.

Comparison with Rival Drug Kisunla

Leqembi now competes with Kisunla, an Alzheimer's treatment developed by Eli Lilly approved in July 2023. Kisunla is also administered via infusion on a once-monthly schedule. Notably, patients on Kisunla stop treatment once brain scans confirm the absence of amyloid plaques.

Safety Considerations

Leqembi and Kisunla carry safety warnings for potential side effects, including brain swelling and bleeds. In order to mitigate these risks, patients are advised to undergo regular MRI monitoring throughout their treatment.

Collaboration and Partnerships

Eisai's development of Leqembi is supported by a collaboration agreement with BioArctic, further strengthening its research and innovation in Alzheimer's treatments.

This new dosing approval could enhance the accessibility and convenience of Leqembi, potentially improving its adoption among patients and healthcare providers. However, safety monitoring and treatment complexities remain critical considerations moving forward.