Overview
Leqembi is approved by the U.S. Food and Drug Administration (FDA) for the treatment of Alzheimer’s disease. It is specifically indicated for individuals in the mild cognitive impairment or mild dementia stage of the disease. Before starting treatment, the presence of amyloid beta pathology must be confirmed. Leqembi is also known by its drug name, lecanemab-irmb.

Leqembi belongs to the category of monoclonal antibodies. It works by targeting and reducing the buildup of beta-amyloid plaques in the brain, which are believed to contribute to the progression of Alzheimer’s disease. By reducing these plaques, Leqembi may help slow cognitive decline associated with the condition.

How do I take it?
Prescribing information states that Leqembi can be administered either as an intravenous (IV) infusion or a subcutaneous (under the skin) injection. 

The recommended starting dosage is an IV infusion once every two weeks for 18 months. After 18 months, treatment may continue either every two weeks or transition to maintenance therapy with an IV infusion once every four weeks or a weekly subcutaneous injection using the Leqembi Iqlik autoinjector. Each IV infusion lasts approximately one hour. Baseline brain MRI scans should be obtained before starting treatment, and additional MRIs are required before the 3rd, 5th, 7th, and 14th infusions to monitor for amyloid-related imaging abnormalities (ARIA).

Leqembi should be administered exactly as prescribed by a healthcare provider.

Side effects
Common side effects of Leqembi include infusion-related reactions, ARIA with microhemorrhages, edema (swelling due to fluid buildup in tissues), effusion (abnormal fluid accumulation in a body cavity), and headaches.

Rare but serious side effects may include severe cases of ARIA, serious intracerebral hemorrhages (brain bleeds greater than 1 centimeter), and symptoms that may mimic an ischemic stroke (caused by reduced blood flow to the brain). Individuals who are ApoE e4 homozygotes (people who have inherited two copies of the APOE4 gene variant) have a higher risk of ARIA. Genetic testing for APOE4 status is recommended before starting treatment.

For more information about this treatment, visit:

Leqembi (Lecanemab-Irmb) Injection, for Intravenous or Subcutaneous
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