Aducanumab is a human monoclonal antibody designed to reduce amyloid-beta plaques, a hallmark of Alzheimer's disease. Developed by Biogen and Eisai, it received accelerated FDA approval in 2021 under the brand name Aduhelm, marking the first new Alzheimer's treatment in nearly two decades. Its approval has been controversial due to mixed clinical trial results and debates over its efficacy, safety, and cost, making it a focal point in discussions on neurodegenerative disease therapies.