In recent months, there have been a number of significant developments with respect to new drug therapies directed against Alzheimer’s disease.
As expected, this did not go unnoticed by healthcare professionals working in the field, individuals living with the disease and those who care for them. Taking stock of data made available so far, is this the panacea we are all hoping for?
Alzheimer’s disease is the most common form of dementia and is characterised by a severe and progressive cognitive decline manifesting itself in memory loss, confusion, language difficulties, mood variations, personality changes and an inability to perform daily activities. It is, undoubtedly, one of the major public health challenges worldwide.
In Malta, it is estimated that there are over 5,000 people currently living with the disease, a figure that is expected to exceed 9,000 by 2050.
What happens in the brain of these individuals is not fully understood. However, research shows an abnormal build-up of toxic amyloid plaques that destroy brain cells.
The damage starts many years before the first symptoms appear and is initially located in areas of the brain that are involved in the formation of memories, in particular, those related to facts and events that need to be consciously encoded and recalled.
As the disease spreads to other areas of the brain, other cognitive functions become compromised. In end-stage Alzheimer’s disease, affected individuals become fully dependent on others for their care.
Due to its complex nature, developing treatments for Alzheimer’s disease has always been a challenge, with the last drug being approved over 20 years ago. However, these last few months saw the emergence of two new ones: lecanemab and donanemab. Although neither of these have the potential of curing the disease, they were shown to have the ability to modify disease progression by targeting and removing the amyloid plaques from the brain. In recent studies, lecanemab and donanemab were reported to slow down the cognitive decline by 27 and 35 per cent respectively.
Although this may be considered as a major scientific breakthrough in the fight against Alzheimer’s disease, it does not come without its caveats
Although this may be considered as a major scientific breakthrough in the fight against Alzheimer’s disease, it does not come without its caveats.
So far, these drugs are only recommended for the mild, early stages of the disease. Important side effects have also been observed in clinical trials with brain swelling and bleeding occurring in a significant number of individuals. Because of this, individuals undergoing such therapy would need to be continuously monitored.
Unfortunately, many healthcare systems, including ours, lack the infrastructure to enable widespread roll-out of such novel treatments. Accessibility to specialised imaging techniques that determine treatment eligibility, together with the availability of highly skilled staff, is lacking.
Furthermore, these drugs are very expensive, costing tens of thousands of euros per patient per year and it is not clear for how long these drugs need to be taken.
Notwithstanding this, the emergence of such new therapies is a remarkable step forward in tackling such a debilitating disease.
Although they are not the cure we were hoping for, they do offer a ray of hope to people with early Alzheimer’s disease in maintaining their quality of life for longer.
It will be interesting to see how such therapies will continue to develop in the coming future as we continue in our quest to figure out how to beat one of the major causes of disability and dependency in old age.
Charles Scerri is an associate professor of dementia studies at the Department of Pathology, University of Malta, vice-chairperson of Alzheimer Europe and member of the scientific board of the EU Joint Programme on Neurodegenerative Disease Research.