FDA Accepts BLA for Leqembi Autoinjector

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The FDA has accepted a biologics licensing application (BLA) for Eisai’s Leqembi (lecanemab-irmb), a subcutaneous 100 mg/mL weekly autoinjector for the treatment of early Alzheimer’s disease, according to a recent news release. A Prescription Drug User Fee Act (PDUFA) action date is set for Aug. 31, 2025.

Alzheimer’s disease is an incurable neurodegenerative disorder that affects more than 6.5 million Americans. Although the root cause is unknown, it is characterized by the buildup of toxic amyloid-beta plaque and protofibrils. Leqembi works by continuously clearing both plaque and protofibrils, therefore slowing cognitive decline. In addition to emotional burden on the patient and caregivers, there is also a financial burden. The estimated cost of caring for Alzheimer’s patients was $321 billion, according to a study published in the American Journal of Managed Care.

This BLA is based on the results from the Clarity AD open-label extension that showed that the weekly subcutaneous formulation of Leqembi reduced amyloid plaque in patients 14% more than the biweekly intravenous formulation. Additionally, there was no cognitive decline in 76% of patients, and 60% showed clinically meaningful improvement by week 18 of treatment.

The Leqembi autoinjector is designed to be used as part of the SC-AI 360 mg weekly maintenance regimen for patients who have completed the biweekly intravenous initiation phase, the exact length of which is still under discussion. At completion, patients can take the 100 mg/mL Leqembi injection at home, which takes about 15 seconds. This could potentially reduce the need for hospital and infusion site visits.

Infusion-related reactions were seen in 26% of Leqembi patients, compared with 7% of patients on placebo, with 75% occurring within the first infusion. Symptoms included fever, chills and nausea.

Additional reactions to Leqembi include amyloid-related imaging abnormalities (ARIA), observed on an MRI as brain edema or sulcal effusions. Symptoms usually resolve over time and include headache, confusion and visual changes. Symptomatic ARIA was seen in about 3% of patients and all cases were resolved.

Leqembi was approved for intravenous use by the FDA in July 2023.

The list price for Leqembi in the United States is $26,500 a year with out-of-pocket cost varying by patient and insurance provider.