Leqembi (lecanemab) is a humanized immunoglobulin G1 monoclonal antibody targeting aggregated forms of beta-amyloid, used for the treatment of Alzheimer's disease.

How to Use Leqembi (Lecanemab)

Correct Administration Route

Leqembi must be administered via intravenous infusion.

Before use, it must be diluted with 250 mL of 0.9% sodium chloride injection and infused through a tubing set equipped with a terminal low-protein-binding 0.2-micron in-line filter, with the infusion time lasting approximately 1 hour.

The diluted medicinal solution should be brought to room temperature before infusion.

Drug Preparation Specifications

Aseptic technique must be adopted, and the required dose should be calculated based on the patient's actual body weight.

Each vial of Leqembi has a concentration of 100 mg/mL. Draw the required volume of the medicinal solution and add it to an infusion bag containing 0.9% sodium chloride injection.

Each vial is for single use only; any remaining medicinal solution should be discarded.

Gently invert the infusion bag to mix the medicinal solution thoroughly; shaking is strictly prohibited.

Principles for Managing Missed Infusions

If a scheduled infusion is missed, the missed dose should be administered as soon as possible.

There is no need to adjust the subsequent administration schedule due to the delayed infusion.

Dosage Adjustment of Leqembi (Lecanemab)

Dosage Adjustment for Imaging Abnormalities

Asymptomatic ARIA-E (Amyloid-Related Imaging Abnormalities - Edema): Administration can be continued for mild cases, but must be suspended for moderate to severe cases.

Symptomatic ARIA-E: Whether to suspend administration should be determined based on the severity of clinical symptoms.

ARIA-H (Amyloid-Related Imaging Abnormalities - Hemorrhage): The timing of suspending administration should be determined based on the severity of imaging findings.

After suspending administration, treatment resumption (if applicable) should be decided based on clinical judgment only after MRI shows improvement in imaging findings and symptoms have resolved.

Medication Use in Special Populations for Leqembi (Lecanemab)

Patients Homozygous for ApoE ε4

Patients homozygous for ApoE ε4 have a higher risk of developing ARIA, including symptomatic and severe ARIA.

ApoE ε4 status testing should be conducted before initiating treatment to assess the risk of ARIA occurrence.

Patients with Renal or Hepatic Impairment

Pharmacokinetic studies of Leqembi have not been conducted in patients with renal or hepatic impairment.

Leqembi is degraded by proteolytic enzymes and is not expected to be eliminated via the kidneys or metabolized by hepatic enzymes.

Pregnant Women

Insufficient data are available to evaluate the risk of Leqembi use in pregnant women.

Lactating Women

There are no data available to determine whether Leqembi is excreted into human milk.