FDA’s Accelerated Approval for First Alzheimer’s Drug since 2003

On June 7, 2021, the FDA granted accelerated approval for Biogen’s Aduhelm (aducanumab), the first approved Alzheimer’s drug since 2003. According to the FDA, an accelerated approval allows drugs for “serious conditions that fill an unmet medical need to be approved based on a surrogate endpoint.” This surrogate endpoint could be a laboratory or physical marker that could potentially predict a clinical benefit, but not a measure of the benefit itself. In the case of Aduhelm, the surrogate endpoint was a reduction in amyloid beta plaques. 

“Researchers evaluated Aduhelm’s efficacy in three separate studies representing a total of 3,482 patients. The studies consisted of double-blind, randomized, placebo-controlled dose-ranging studies in patients with Alzheimer’s disease. Patients receiving the treatment had significant dose-and time-dependent reduction of amyloid beta plaque, while patients in the control arm of the studies had no reduction of amyloid beta plaque.”(1) 

The drug has also faced criticism from experts for its Fast Track approval. In one of the key studies, the drug failed to show reduction in cognitive decline while showing a benefit in another separate study. FDA’s independent experts recommended against approving the drug, requesting another large study to settle the conflicting trial results. However, some physicians say they would still prescribe the drug after discussing the risks and benefits with their patients.(2) 

Aduhelm is administered monthly over approximately one hour as an intravenous infusion. Side effects include amyloid related imaging abnormalities (ARIA) and hypersensitivity reactions.(3) 

The drug is priced at $56,000 annually, which is significantly higher than the $8,300 estimated by the Institute for Clinical Economic Review (ICER). This raises key coverage questions for plan sponsors to consider. Some commercial payor such as Cigna and Humana are look to Centers for Medicare and Medicaid Services (CMS) as it reviews FDA’s approval decision regarding Aduhelm.(4)