Alzheimer's disease was long considered untreatable, but that assumption is no longer universally valid, according to this year's World Alzheimer Report, as reported by Science Alert.
In just the past five years, new drugs have been shown to moderately slow decline in the early stages of Alzheimer's, while growing evidence suggests that some cases of dementia could even be delayed or prevented by reducing risk factors.
Today, hundreds of clinical trials worldwide are investigating potential drugs, new diagnostic options, and lifestyle interventions to identify, treat, or delay cognitive decline.
The possibility of a cure is still distant, but "it seems a more tangible prospect than ever," according to the 2026 World Alzheimer Report, co-authored by Alzheimer's Disease International (ADI) and renowned health journalist Paul Gallagher.
"After decades in which dementia was widely regarded as an inevitable consequence of aging and neurodegeneration, with few therapeutic options beyond symptom management, research has entered an era of unprecedented activity," the report states.
"Alzheimer's disease is no longer universally described as untreatable; instead, it is increasingly seen as a condition for which earlier diagnosis, a better understanding of the disease biology, and a wider range of interventions can collectively improve outcomes," according to the document.
ADI calls itself "the global voice of dementia." It is a worldwide federation of dementia associations in official relations with the World Health Organization (WHO).
Every year since 2009, ADI has published a report on dementia research, each year addressing a different theme.
This year's report is titled "A New Era in Dementia Clinical Trials" and argues that dementia research has entered a period of remarkable scientific momentum.
The authors argue this moment is similar to oncology in the 1990s, when the first generation of cancer therapies, though imperfect, paved the way for effective drug combinations, precision medicine, and early intervention.
"For now, there is no single major breakthrough to rival the discovery of penicillin or the advent of statins. Instead, there is something more discreet… It is a transition from treatment to prevention, from molecule to lifestyle, from inevitability to possibility," the report argues.
As the global population ages, some estimates predict that by 2050, 139 million people will be living with dementia. Even modest delays in the onset of cognitive decline could translate into millions fewer cases.
Recently, for example, the WHO published new guidelines on how to reduce dementia risk.
According to recent research, up to 45% of dementia cases could potentially be prevented or delayed by addressing 14 modifiable risk factors throughout life.
These include high blood pressure, depression, lack of physical activity, smoking, diabetes, excessive alcohol consumption, and high cholesterol.
Clinical trials for dementia are also at a historic moment, according to the report.
Between 2000 and 2020, over 99% of experimental drugs failed in clinical trials. But the recent launch of donanemab and lecanemab was a huge moment, argues Cath Mummery, director of the UK Dementia Clinical Trials Network.
These were the first fully approved drugs shown to moderately slow the progression of early Alzheimer's, rather than just treating its symptoms.
"What we really wanted was a bigger effect on patients, but it was a huge moment because it showed you can change the course of the disease," Mummery says in the report.
"This is the foundation. It's the first brick, and there is an enormous amount to build on it," Mummery adds.
Not all researchers are convinced that donanemab and lecanemab provide significant clinical benefits; for example, they do not appear to work equally for every patient or in every part of the brain.
However, the approval of these two drugs represents a positive turn of events that has changed expectations about what dementia research can achieve, the new report argues.
In the last decade, the number of candidate drugs under investigation for dementia has increased by about 40%. Researchers are currently evaluating 158 potential therapies in 192 clinical trials worldwide. This year alone, results are expected from eight Phase III clinical trials—which rigorously test treatments on large numbers of people compared with standard care.
Many of these drugs are already approved for human use. In fact, more than a third of dementia drugs in development were originally created for other conditions.
Unfortunately, however, many patients in the early stages of cognitive decline do not know these possibilities exist.
Consultant neuroradiologist Emer MacSweeney told ADI: "The biggest mistake happening right now is that people who are clearly, obviously most likely in the early stages of Alzheimer's disease are ignored and completely missed, because that window of opportunity for treatment is very small."
MacSweeney says patients are often uninformed about clinical trials or how to access new drugs.
"This is a pandemic. We need a change of mindset in the medical profession to ensure more people are informed about clinical trials and supported to participate in them. We need action, not rhetoric," MacSweeney stresses.
One of the biggest obstacles is diagnosis. A new generation of treatments that can potentially slow memory and thinking decline is welcome, but these drugs are only useful if they actually reach patients.
In the UK, for example, only about 2% of people diagnosed with Alzheimer's have access to a state-of-the-art diagnostic test (the gold standard), according to a study co-led by Jonathan Schott, Chief Medical Officer at Alzheimer's Research UK.
Although these new tools show promise in initial studies, they still need to be tested across the whole population to see if they can accurately identify those with early signs of cognitive decline.
"A revolutionary drug means little if most people living with dementia are not identified in the first place. In that sense, the future of dementia care may depend as much on family doctors in Havana, Lima, or Bangalore as it does on billion-dollar labs in California," the ADI report argues.
According to the report, there are real reasons for optimism. Now we just need to ensure that scientific progress is matched by clinical progress.
"The challenge for the next decade is to ensure that participation in dementia research no longer depends on persistence or luck," the report concludes, "but becomes a realistic opportunity for all who wish to consider it."