FDA's Approval Of Aduhelm, First New Drug For Alzheimer's Disease In Nearly 20 years, Offers Hope For Millions

U.S. drug regulator Food and Drug Administration announced that it has granted conditional approval to an experimental new drug Aduhelm (aducanumab) for the treatment of Alzheimer’s disease.

First identified 115 years ago by a German psychiatrist Alois Alzheimer, the disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and eventually, the ability to carry out simple tasks.

While the specific causes of Alzheimer’s disease are not fully known, it is characterized by changes in the brain—including amyloid plaques and neurofibrillary, or tau, tangles—that result in loss of neurons and their connections. These changes affect a person’s ability to remember and think.

Aduhelm represents a first-of-its-kind treatment approved for Alzheimer’s disease. It is the first new treatment approved for Alzheimer’s since 2003 and is the first therapy that targets the fundamental pathophysiology of the disease.

Biogen, a biotechnology firm based in Cambridge (MA) and its Japanese partner Eisai developed aducanumab. It is administered through intravenous infusion to treat early Alzheimer's disease. The drug was developed for patients with mild cognitive impairment, not severe dementia.

FDA said that the conditional approval was based on evaluation of 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.

Under the accelerated approval provisions, which provide patients suffering from the disease earlier access to the treatment, the FDA has directed Biogen, to conduct a new randomized, controlled clinical trial to verify the drug’s clinical benefit. If the trial fails to verify clinical benefit, the FDA may initiate proceedings to withdraw approval of the drug.

Controversy Over The Approval

FDA's approval comes with its share of controversy. Last November, ten out of the 11 members of the Peripheral and Central Nervous System Drugs Advisory Committee appointed aby the FDA voted against approving the drug on the basis of the research presented.

The committee left the decision to FDA.

"In all studies in which it was evaluated, however, Aduhelm consistently and very convincingly reduced the level of amyloid plaques in the brain in a dose- and time-dependent fashion," Patrizia Cavazzoni, M.D., director of the FDA’s Center for Drug Evaluation and Research said on Monday. "It is expected that the reduction in amyloid plaque will result in a reduction in clinical decline."

“Currently available therapies only treat symptoms of the disease; this treatment option is the first therapy to target and affect the underlying disease process of Alzheimer’s. As we have learned from the fight against cancer, the accelerated approval pathway can bring therapies to patients faster while spurring more research and innovation.” Cavazzoni added.