Biogen Inc. announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to BIIB080, an investigational antisense oligonucleotide (ASO) therapy targeting tau, for the treatment of Alzheimer’s disease. Fast Track designation is intended to facilitate the development and expedite the review of investigational drugs that treat serious conditions and address unmet medical needs.

“We are encouraged by the FDA’s Fast Track designation for BIIB080, which highlights the urgent need for innovative treatments targeting tau pathology in Alzheimer’s disease,” said Priya Singhal, M.D., M.P.H., Head of Development at Biogen. “Alzheimer’s is a complex and fatal disease that we believe will require multiple therapeutic approaches to address its diverse pathologies. BIIB080, an investigational antisense therapy, is a differentiated approach to targeting tau, with promising potential for patients. We are advancing this program with urgency on behalf of people living with Alzheimer’s and their families.”

BIIB080 is the first tau-targeting ASO to enter clinical development for Alzheimer’s disease and is currently being evaluated in the global Phase 2 CELIA study in individuals with early-stage disease. As previously announced, results from the Phase 1b study showed dose-dependent reductions in soluble tau protein in cerebrospinal fluid (CSF), decreases in aggregated tau pathology in the brain as measured by positron emission tomography (PET), and favorable trends in exploratory clinical outcomes, supporting the potential for clinical benefit. In the high-dose groups, favorable trends were observed across multiple exploratory measures of cognition and function. The Phase 2 CELIA study is now fully enrolled, with a data readout expected in 2026.