Biogen has officially withdrawn its marketing application for its controversial Alzheimer's therapy Aduhelm in the European Union, following clear signals from regulators that the current clinical data package would not support approval. The decision came after unsuccessful attempts to address the European Medicines Agency's (EMA) concerns about the drug's efficacy.
The European regulatory committee (CHMP) had expressed significant doubts about Aduhelm's clinical benefits in December. While acknowledging the drug's ability to reduce beta-amyloid levels in the brain, regulators highlighted the lack of convincing evidence linking this biological effect to meaningful clinical improvements in Alzheimer's patients.
Clinical Evidence Concerns
The CHMP's evaluation revealed conflicting results from the two pivotal studies submitted in the application. Regulators concluded that the data failed to demonstrate consistent effectiveness in treating early-stage Alzheimer's disease patients. Biogen's subsequent efforts to challenge this assessment through a re-examination request proved unsuccessful.
Despite the setback, Biogen maintains its confidence in aducanumab's safety profile. "We stand by the safety of aducanumab, and we look forward to upcoming data readouts to continue to provide important information on the science of this new class of compound," the company stated.
Global Regulatory Landscape
The European withdrawal adds to a series of challenges facing Aduhelm's global commercialization. While the FDA granted accelerated approval last year based on surrogate endpoint data, the decision has faced significant scrutiny. The US Centers for Medicare and Medicaid Services (CMS) recently restricted coverage to patients enrolled in clinical trials, effectively limiting the drug's accessibility to a few thousand patients.
Similar skepticism from Japanese regulatory authorities, who have also demanded additional data, has further complicated Aduhelm's market prospects. These setbacks have forced Biogen to implement substantial cost-cutting measures, including workforce reductions aimed at saving $500 million annually.
Path Forward
Biogen is now focusing on generating additional efficacy data through the newly planned ENVISION study. The company has submitted the trial protocol to the FDA and plans to begin patient screening and enrollment soon, with results expected in 2026.
The company's partnership structure for Aduhelm has also evolved, with Japanese pharmaceutical firm Eisai converting its previous 50:50 profit-sharing agreement to a royalty-based arrangement, reducing its financial commitment to the drug's development. However, the companies' collaboration on lecanemab, another amyloid-targeting drug candidate, remains unchanged.
