The US Food and Drug Administration (FDA) has granted accelerated approval for Biogen’s and Eisai’s Aduhelm (aducanumab) for treating Alzheimer’s disease. It is the first new treatment approved by the FDA for Alzheimer’s since 2003 and is the first therapy that targets the fundamental pathophysiology of the disease, according to the FDA, and has been slated by some analysts as a potential blockbuster.

Aduhelm was approved using the FDA’s accelerated approval pathway, which can be used for a drug for a serious or life-threatening illness that provides a meaningful therapeutic advantage over existing treatments. Under the accelerated approval provisions, the FDA is requiring Biogen to conduct a new randomized, controlled clinical trial to verify the drug’s clinical benefit.

Continued approval for Aduhelm’s indication as a treatment for Alzheimer’s disease may be contingent upon verification of clinical benefit in confirmatory trial(s).

Aducanumab addresses a defining pathology of Alzheimer’s disease by reducing amyloid beta plaques in the brain and slowing clinical decline. The drug was evaluated in two Phase III clinical trials in patients with early stages of Alzheimer’s disease (mild cognitive impairment and mild dementia) with confirmed presence of amyloid pathology.

In an atypical move, the full FDA granted approval following an earlier opinion by a FDA advisory committee to not approve the drug. In November (November 2020), an advisory committee of the FDA voted to reject approval of aducanumab, citing that the drug failed to demonstrate efficacy and more research was needed. FDA advisory committee recommendations are non-binding although they have historically been taken by the full FDA when considering a drug for approval.

In late January (January 2021), the FDA extended the review period for the biologics license application (BLA) for aducanumab by three months from March 7, 2021 to June 7, 2021. As part of the ongoing review, Biogen submitted a response to an information request by the FDA, including additional analyses and clinical data, which the FDA considered a major amendment to the application that required additional time for review. Biogen first submitted the aducanumab BLA to the FDA in July 2020.

Biogen licensed aducanumab from Neurimmune, a Zurich, Switzerland-based bio/pharmaceutical company. Since 2017, Biogen and Eisai have collaborated on the development and commercialization of aducanumab globally.

Some analysts have pointed to potential blockbuster status for the drug. A recent analysis by Evaluate Vantage/EvaluatePharma projects $4.8 billion in forecast sales in 2026.

Source: US Food and Drug Administration, Biogen, and Eisai