A large review found that the Alzheimer's drugs now available (very expensive!) actually do not slow down the disease. They don't work. In other words, they should never have been approved.
The authors of the study said it appears that the drugs result in little to no difference ("no clinically meaningful effect") in a range of measures, including reducing dementia severity. And their use increases the risk of bleeding and swelling of the brain.
A few years ago journalists uncovered that there was significant fraud involved in the research and drug approvals (not surprising when so much money is involved).
For decades, Alzheimer's research mainly (only) focused on abnormal protein deposits in the brain (amyloid plaques) and misfolded protein tau tangles in the brain. But many researchers are suggesting that other causes of Alzheimer's should be looked at, including viral causes and chronic inflammation.
Excerpts from The Conversation: Alzheimer's Drugs Offer Little Benefit, Major Review Finds - And the Reasons Go Deeper Than the Science
How is it possible to spend tens of billions of dollars developing drugs to treat a serious disease that affects millions of people, and yet end up with something that does not work? This is a mystery that has bedevilled Alzheimer’s research for years.
A new review of the evidence has concluded that the leading class of Alzheimer’s drugs “probably result in little to no difference” in a range of measures, including reducing dementia severity.
These findings are disappointing, not just for researchers and drug companies, but also for the tens of millions of people and their families suffering from the effects of a devastating disease.
Medical research is often reported through success stories, but Alzheimer’s disease has remained stubbornly resistant to the development of life-changing breakthroughs. This has not gone unnoticed. A couple of years ago, investigative journalists uncovered significant fraud in important studies underpinning some of the science behind the leading Alzheimer’s drugs.
While this fraud is not solely responsible for the lack of progress in Alzheimer’s research, it does reveal how vested interests can distort science and how commercial interests can sometimes override indications that a specific approach may not actually be working. It also reveals how social, political and economic factors can distort and hold back entire fields of research.
At one point, those proposing that amyloid deposits (or at least the molecular processes leading to them) were the main cause of the disease were even referred to as “Baptists”, while those holding tau as responsible were called the “Tauists”. Although these have been the main two theories as to the cause of the disease, there have been numerous others, such as linking the disease to the abnormal behaviour of neurotransmitters, inflammation, presence of pollutants, age-related changes, DNA damage, viruses and even sleep disturbance.
In situations like this, when there are many competing theories, researchers who start working on one theory can start to become entrenched. This is an unfortunate byproduct of competitive funding models, where research money tends to flow to the researchers who are most successful at arguing that their approach is the most promising and therefore worthy of receiving more research money. This is an interesting example of how science is not always an entirely objective endeavour.
This pressure on researchers to publish papers and attract funding is probably a contributing factor to the significant fraud linked specifically to some working on the amyloid hypothesis for Alzheimer’s. In one case, a researcher in the US was forced to resign from his university following the retraction of a much-cited paper, and the discovery that over 20 other papers may have similarly questionable data.
It would be nice to think that the main incentive for most researchers might be solving a problem or curing a disease, but the actual situation is far more complex. Research relies on funding, and researchers get jobs based on reputation, often in the form of publications. Because of this, the wrong behaviour can become incentivised.