FDA Requires MRI Scan for Biogen's Leqembi Alzheimer's Therapy Amid Safety Concerns

The FDA is tightening safety guidelines for Biogen's Leqembi Alzheimer's therapy due to concerns over a rare but potentially fatal side effect. Patients will now be required to undergo an MRI scan before the third infusion, as opposed to the fifth, seventh, and 14th infusions previously recommended. The new guidelines aim to help identify amyloid-related imaging abnormalities with edema sooner.

The U.S. Food and Drug Administration (FDA) has announced stricter safety guidelines for Biogen's Leqembi (lecanemab), an Alzheimer's therapy. Effective immediately, patients receiving Leqembi will now be required to undergo an MRI scan before the third infusion, as opposed to the previous recommendations for the fifth, seventh, and 14th infusions. This change is aimed at detecting amyloid-related imaging abnormalities with edema (ARIA-E) earlier, a potentially life-threatening condition characterized by brain swelling or fluid accumulation [1].

Leqembi, approved in 2023, targets beta-amyloid plaques, protein deposits in the brain linked to Alzheimer's progression. By reducing these plaques, the drug aims to preserve cognitive function in its early stages. However, ARIA-E, while often symptomless, can lead to seizures, status epilepticus, and, in rare cases, death. The FDA's decision follows an in-depth analysis of six early deaths linked to ARIA-E, prompting the agency to revise Leqembi's prescribing information [2].

The new guidelines increase the cost and complexity of monitoring for healthcare providers and patients, potentially deterring prescriptions in resource-constrained settings. For Biogen, this creates a delicate balance between scaling a potentially transformative drug and managing risks that could erode its market share. The long-term profitability of Leqembi hinges on successfully demonstrating its clinical benefits in a confirmatory trial and managing the risks associated with ARIA-E [3].

The FDA's actions reflect a growing trend toward proactive risk management in the pharmaceutical industry, particularly in high-risk therapeutic areas. As more amyloid-targeting therapies enter the market, regulators are likely to intensify their scrutiny, highlighting the need for companies like Biogen to navigate regulatory challenges while ensuring patient safety.

References:
[1] FDA to recommend additional, earlier MRI monitoring for patients with Alzheimer's disease taking Leqembi (lecanemab) [https://www.fda.gov/drugs/drug-safety-and-availability/fda-recommend-additional-earlier-mri-monitoring-patients-alzheimers-disease-taking-leqembi-lecanemab]
[2] FDA mandates earlier MRI monitoring for Biogen’s Leqembi due to ARIA-E deaths linked to amyloid-targeting therapy [https://www.ainvest.com/news/regulatory-vigilance-future-biogen-leqembi-balancing-innovation-risk-alzheimer-drug-development-2508/]
[3] The FDA has recommended earlier brain imaging scans for patients on Eisai and Biogen's Alzheimer's drug Leqembi to monitor for brain swelling [https://www.ainvest.com/news/fda-advises-increased-monitoring-brain-swelling-leqembi-patients-2508/]