By Amira Thadani
According to the current estimations, 44 million people worldwide suffer from Alzheimer’s disease. In the U.S., this debilitating condition is the sixth-leading cause of death, and in 2016 alone, 15.9 million families and friends provided 18.2 billion hours of assistance to their loved ones with the disease. (Hoffman, 2021) Clearly, the problem at hand is devastating, and something needs to be done about it. Over the past decade, scientists have been trying to wrap their heads around finding a suitable cure - an effort which has, for the large part, proved to be in much vain. But what if a miracle drug does exist? One that could instantaneously wipe out all symptoms of Alzheimer’s. What if the ‘what if’ in the question need not be there? Because in that case, ‘aducanumab’ may be the exact answer to what we're looking for... or not, depending on who you ask.
On the 7th of June, the FDA approved the first drug since 2003 that claims to cure the underlying pathophysiologies of Alzheimer’s disease. This drug was developed by the pharmaceutical company Biogen Inc. and has been given the trade name ‘Aduhelm’. Since its approval,it has garnered much attention from the press, patient community, elected officials, various stakeholders,and medical practitioners. Some of the attention has been positive, while some have increasingly been critical of the drug. Robert Howard, Professor of Old Age Psychiatry at UCL is one amongst many scientists who is unhappy about the decision: “I consider the approval of aducanumab represents a grave error that will have only negative impact on patients and their families and that could derail the ongoing search for meaningful dementia treatments for a decade.’’ In fact, in just November of last year, after the Phase III trial of this drug could not provide primary evidence of its effectiveness towards treating Alzheimer’s disease, 10 members of the Peripheral and Central Nervous System Drugs Advisory Committee voted against the approval of the drug while one abstained from voting.(Cavazzoni, 2021)
So, why did things shape out differently this time,and does the drug actually work? To answer these questions, we’ll first have to look at the science behind the disease itself.
Alzheimer’s is thought to be caused by the abnormal accumulation of two kinds of proteins in and around brain cells: amyloid, which forms plaques deposits, and tau proteins, which deposit in the form of tangles. Although scientists are still unclear as to what leads to these proteins building up in the brain, they do know this process often starts off years before symptoms begin to appear. Additionally, as more and more brain cells become infected, a decrease in chemical messengers (neurotransmitters) can be observed. These messengers are crucial to the process of signalling between brain cells. Over time, due to the lack of proper signalling, parts of the brain shrink - the first of these areas typically being those responsible for storing our memories. (White, 2021) Aducanumab targets a specific type of amyloid protein called Amyloid beta (Aβ), found in the brains of people with Alzheimer's disease, in the hopes of reducing its buildup. (Carroll, 2020). However, one major problem is that all this is being done without scientists properly understanding the role of amyloid proteins in the development of the neurodegenerative disease.
Regardless of this fact, results from the latest randomised, placebo-controlled trial is encouraging: all doses of aducanumab (given as monthly infusions into the bloodstream) significantly reduced amyloid plaques in the brains of 165 patients. The greatest reductions were found to be present at higher doses. Aducanumab also appeared to slow the rate of cognitive decline. (Sandburg, 2021) Still, skepticism persists because of claims of the newest trial results being unreliable, and evidence of harmful side effects of the drug. So, the question of whether aducanumab really works or not can only now be determined as we slowly wait and watch to see how real patients, outside of trials, respond to the drug.
You may ultimately ask yourself, ‘Why should I care?’. Well, for one, research is increasingly pointing towards rates of Alzheimer’s disease growing in the future. Between 2000 and 2019 itself, the number of deaths from Alzheimer's disease increased by 145.2% - more than double its original amount. (Goldman, Lakdawalla, 2021). Moreover, this upward trend is likely to continue well into the future. Let’s just hope that one day none of us would need to care about it anymore. And, for all we know, those days are approaching sooner than we actually think.
Hoffman, M., 2021, Aducanumab Approved for Alzheimer Disease Treatment, Neurology Live (online):https://www.neurologylive.com/view/aducanumab-biogen-approved-alzheimer-disease-modifying-treatment. (Accessed: 14th June, 2021).
Cavazzoni, P., 2021, FDA’s Decision to Approve New Treatment for Alzheimer’s Disease, U.S. Food and Drug Administration. (online): https://www.fda.gov/drugs/news-events-human-drugs/fdas-decision-approve-new-treatment-alzheimers-disease. (Accessed: 14th June, 2021).
White, C., 2021, What Explains the FDA’s Big Gamble on Aducanumab, the New Alzheimer’s Drug? The Wire. (online): https://science.thewire.in/the-sciences/what-explains-the-fdas-big-gamble-on-aducanumab-the-new-alzheimers-drug/. (Accessed: 14th June, 2021).
Carroll, J., 2021, Expert panel review on Alzheimer’s drug aducanumab becomes a one-day trial by fire as critics turn their guns on Biogen — and the FDA. Endpoints News. (online): https://endpts.com/fda-panel-review-on-the-alzheimers-drug-aducanumab-turns-into-a-one-day-trial-by-fire-as-critics-turn-their-guns-on-biogen-and-the-fda/. (Accessed: 14th June, 2021).
Sandburg, B., 2021, What did US do wrong in its review of aducanumab adcoms members have a list. Pharma Intelligence. (online): https://pharmaintelligence.informa.com/resources/product-content/what-did-us-fda-do-wrong-in-its-review-of-aducanumab-adcom-members-have-a-list. (Accessed: 14th June, 2021).
Goldman, D., Lakdawalla D., 2021, FDA’s approval of aducanumab paves the way for ‘more momentous’ Alzheimer’s breakthroughs. Stat News. (online): https://www.statnews.com/2021/06/07/fda-aducanumab-approval-paves-way-momentous-alzheimers-breakthroughs/. (Accessed: 14th June, 2021).