This week's decision by the US Food and Drug Administration to approve the use of aducanumab or Aduhelm to treat patients with Alzheimer's disease may be an inflection point in the race to find a cure for dementia.
Aduhelm is reported to tackle the progressive degenerative disease of the brain by reducing deposits of amyloid plaque that impair memory once they begin to build up. Other previously licensed inhibitor drugs only seek to slow down cognitive decline rather than address the disease head on, which is why there is so much interest in this new treatment.
Biogen, the company developing the drug, says the treatment will answer a significant unmet need for those diagnosed with the disease, although critics argue its performance was mixed during late-stage trials.
If it lives up to its billing, however, the drug will bring hope to an arena where traditionally there has been next to none.
The FDA’s decision, however, also represents an apparent U-turn from the body’s previous pronouncement on the progress of the drug in November 2020.
Last year, the FDA's Peripheral and Central Nervous System Drugs Advisory Committee voted on the question of whether there was strong evidence to support the effectiveness of aducanumab in treating Alzheimer's. Eight members of the committee voted no, two were uncertain and one member said yes.
This may explain why this week’s statement on the approval acknowledged the question marks around the drug’s effectiveness.
In a memo released on Monday, Dr Patrizia Cavazzoni, director of the FDA Centre for Drug Evaluation and Research, concluded that the data provided for approval was "highly complex and left residual uncertainties regarding clinical benefit" and said it was unsurprised that there was so much attention on the approval.
Dr Cavazzoni went on to say that the FDA had determined that the drug would be given its accelerated approval path, which gives access to “potentially valuable therapies for patients with serious diseases where there is an unmet need and where there is an expectation of clinical benefit despite some residual uncertainty.”
Whatever way you look at it, this is a volte-face from the apparent hard-no delivered in November. Ultimately, the FDA decided the potential benefits exceed the risks.
Some of the reasons why this decision has been applauded by carers and families of those diagnosed with dementia is grounded in the belief that trying some form of treatment, even if it proves unsuccessful, is preferable to doing nothing. Hope and possibility is always better than despair and inaction.
In that respect, the accelerated approval of Aduhelm may yet be seen as a moon shot, although the real destination point must be to establish what triggers the amyloid plaques and to see if they can be identified and reversed at an earlier stage.
The unstated gamble in the Aduhelm accelerated approval is that it will turbocharge that space for dementia research or, indeed, Biogen’s drug may turn out to fully answer those unmet needs by overcoming those residual question marks. The lost cause of dementia may just have found a patron.
All this hope comes with a heavy price tag.
Infusions of Aduhelm will cost around $4,000 a month or $56,000 a year (Dh205,500) and with no certainty that the drug will work or that health insurers or healthcare providers would support the treatment. Patients would also have to pay for regular brain scans, which are rarely cheap.
No wonder it has been described as a blockbuster drug for Biogen, but it may yet break the banks of hopeful families if it is widely adopted. Indeed, it is of a similar price to residential care costs for someone diagnosed with dementia, so while there may be considerable emotional comfort in pursuing treatment there is little economic benefit when weighed against nursing home charges.
Governments too have borne enormous financial costs to keep societies at home or on furlough during the coronavirus pandemic, but will they be willing to pay such bills to meet dementia prevention, cure and treatment needs for a significant portion of their populations? History tells us, probably not.
By contrast, Aricept, which is one of the inhibitor drugs that seeks to slow not stop progression of the disease, costs around $350 a month or $4,200 a year (Dh15,500), but only helps in the early stages of Alzheimer’s and in some cases has not been effective at all. The window of usefulness can, and often does, snap shut very quickly and, in any case, the side effects can make it hard to use for very long.
This is not to present a field of bad choices, because Aduhelm’s accelerated approval is undoubtedly significant and, equally, inhibitor drugs, such as Aricept, have proven valuable by delaying decline in many people.
Last month, Alzheimer’s Disease International published a report on global progress to meet World Health Organisation targets to develop national dementia plans by 2025. ADI estimates that 50 million people live with dementia today. That figure could rise to more than 150 million people by 2050. A new case of dementia is diagnosed every three seconds of every day, somewhere in the world. The report concludes that we are underprepared for an advancing dementia crisis, which makes Aduhelm’s approval all the more timely.
The ADI says the pandemic has given us insight into what happens when the world is unprepared for a health crisis. More than 3.7m people have died since the coronavirus crisis began. Estimates also suggest a significant portion of those deaths were among people diagnosed with dementia. The emotional heartache and societal complications delivered by the pandemic in general are almost immeasurable.
The next few years will tell us whether Aduhelm is a genuine turning point or merely another marker on the long and never-ending road to beat Alzheimer’s. Let’s hope it is a watershed. Don’t be surprised if it is not.
Nick March is an assistant editor-in-chief at The National