Biogen and Eisai Face Setback in Leqembi's Development Path

Key Points

• Biogen (BIIB) and Eisai face a delay in filing the Leqembi subQ Biologics License Application due to FDA's request for additional immunogenicity data.
• The delay has raised valuation concerns and is seen as negative for sentiment among investors and analysts.
• Despite the setback, the global development and co-promotion efforts for Leqembi continue, with plans to address the FDA's requirements by March 2024.

In this news

Biogen Inc. Common Stock (BIIB) and its partner Eisai have encountered a significant hurdle in the development of Leqembi, a promising treatment for Alzheimer's disease. The companies were unable to meet their March deadline for filing the Leqembi subcutaneous (subQ) Biologics License Application due to the FDA's request for additional immunogenicity data. This delay has raised concerns among analysts and investors, with Jefferies highlighting the need for a Fast Track designation before a rolling submission can commence, adding complexity to the process. Furthermore, the valuation of Biogen could be impacted by this delay, according to Jefferies, while Wells Fargo analysts have described the setback as negative for sentiment and unexpected, raising concerns about the variation between subQ and IV administration.

Despite the setback, Eisai and Biogen have submitted a Supplemental Biologics License Application (sBLA) to the FDA for monthly lecanemab-irmb (Leqembi) intravenous maintenance dosing for Alzheimer's disease treatment. Leqembi has already been approved in the U.S., Japan, and China, with applications under review in multiple other countries. The FDA has informed Eisai that a Fast Track designation specific for the subcutaneous formulation of lecanemab is needed for rolling review for weekly maintenance therapy. Eisai plans to initiate a rolling Biologics License Application (BLA) for lecanemab subcutaneous maintenance therapy in March 2024 to address the FDA's requirement for additional immunogenicity data.

The collaboration between Biogen (BIIB) and Eisai on Leqembi's development and commercialization represents a crucial step in the fight against Alzheimer's disease. Despite the current challenges, the global development and co-promotion efforts underscore the commitment of both companies to advancing Alzheimer's treatment. With Eisai leading lecanemab's development and regulatory submissions globally, and both companies co-commercializing and co-promoting the product, there is hope that the additional data required by the FDA will be provided in a timely manner, paving the way for Leqembi's broader availability to patients in need.