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# FDA Delays Review Action on Alzheimer’s Drug
- URL: https://www.fdaweb.com/fda-delays-review-action-on-alzheimers-drug/
- Published: 2026-05-11T12:00:00.000Z
- Updated: 2026-09-14T13:39:01.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5161124

Eisai and Biogen say FDA has delayed by three months its decision on a subcutaneous starting-dose formulation of Alzheimer’s drug Leqembi (lecanemab) after the agency requested additional information during its review. The new review action target date for the supplemental BLA is 8/24\. The application seeks approval of once-weekly subcutaneous injections of Leqembi IQLIK as an initial treatment option for patients with early Alzheimer’s disease.

According to the companies, the agency determined that newly submitted information constituted a “major amendment” to the application, automatically extending the review clock to provide time for a full evaluation of the materials. Eisai and Biogen say the agency “has not raised any concerns to date regarding the approvability” of the filing.

The filing builds on FDA’s 8/2025 approval of a subcutaneous maintenance dosing regimen for Leqembi, which is currently marketed primarily as an intravenous infusion. Approval of a starting-dose injection option could further simplify administration and expand flexibility for patients and providers using anti-amyloid therapies.

Eisai and Biogen note their submission included clinical data from multiple studies and dosing regimens evaluating subcutaneous administration of lecanemab.

The drug carries a Boxed Warning for amyloid-related imaging abnormalities, or ARIA, a class effect associated with anti-amyloid antibodies. ARIA can involve brain swelling or bleeding abnormalities detectable on MRI scans and, in rare cases, can be serious or fatal. Patients carrying two copies of the ApoE ε4 gene variant face a higher risk of developing ARIA, and the prescribing information recommends genetic testing discussions before treatment initiation, according to the companies.