The United States’ Food and Drug Administration on Monday approved aduhelm, a drug used in the treatment of Alzheimer’s. This is the first drug to be approved for the disease in the US since 2003.

In a statement, the Food and Drug Administration said that the drug was approved using an accelerated approval pathway, which is given when the medicine for life-threatening or serious diseases has “meaningful therapeutic advantage” over the existing treatments.

As part of the accelerated approval approach, the drug will have to undergo a post-approval trial to verify if it has the expected clinical benefit. The agency can withdraw the approval to the drug if it fails to show the benefits in the trial.

Alzheimer’s is a progressive brain disorder that slowly destroys memory and thinking skills, and then eventually takes away the ability of the patient to do simple tasks, according to the health agency. Although the specific causes of the disease are not completely known, it is characterised by changes in the brain that leads to loss of neurons (nerve cells) and their connections. These changes affect a person’s ability to remember and think. Nearly 6 million, or 60 lakh, US residents and many others around the world have Alzheimer’s.

The drug is produced by multinational biotechnology company Biogen, which is based out of Cambridge, Massachusetts.

Drugs and treatment given for Alzheimer’s do not reverse the brain damage but treat other related symptoms such as anxiety and insomnia, reported AP. According to the health agency, aduhelm is the only drug that can likely treat the disease.

The drug, aduhelm, also called aducanumab, helps in clearing a protein linked to Alzheimer’s, beta-amyloid. While other experimental drugs have achieved this before, they have made no difference in the ability of the patients to think, take care of themselves or live independently.

Besides beta-amyloid being a factor in causing the disease, new researches show that family history, education and chronic conditions such as diabetes and heart-related ailments may also play a role.

In a trial, patients taking the drug saw their thinking skills decline 22% more slowly than patients taking a placebo treatment. However, it is unclear if the data translates into practical benefits such as the patient’s ability to have greater independence, according to AP.

Debate over approval

The approval to the drug has flared up debates over the standards used to assess treatment for hard-to-treat conditions, according to the news agency. While some groups representing Alzheimer’s patients and their families argue that any therapy that has chances of small benefit should be approved. On the other hand, experts say that approving the drug could set a dangerous precedent and in future allow similar permission granted to treatments of questionable benefits.

Aduhelm was granted approval despite the health agency’s outside panel of neurological experts criticising the product. The group had voted against a series of questions on whether the reanalyzed data from a single study by Biogen showed that the drug was effective.

In 2019, Biogen had suspended two studies after results suggested that the drug would not meet the goal of slowing mental and functional decline in patients suffering from the disease. However, months later, the biotechnology firm said that the analysis of one of the studies showed that drug was effective at higher doses. The company claimed that the drug failed initially because patients were not given high enough doses to slow the disease.

This change in the dosing scheme had raised questions among experts, including those in the health agency’s panel. The Food and Drug Administration, however, does not need the approval of the outside panel to grant permission to a drug for use. The agency has earlier too disregarded the inputs of the panel.