The Reality of Alzheimer’s Treatments: Why Drugs Keep Failing

Unfortunately, the outlook of drug treatment for Alzheimer’s Disease is not a positive one. A recent study examined 244 treatments in over 400 trials between 2002-2012 and over 96% failed. That is the highest failure rate of any disease.

With Dementia being one of the leading causes of death, it is a tremendous strain on the health care system. With research progressing slowly, and the high failure rates of treatments, we may not meet the goal of a cure by 2025.

‘We need to free up regulation so that we can test ground-breaking new drugs, and examine whether the period for market exclusivity could be extended.’ – Dennis Gillings.

Dementia is a general term that includes a set of symptoms relating to memory loss and cognitive function loss. Alzheimer’s Disease is the most common form, but there is also Frontotemporal Dementia, Dementia with Lewy Bodies, and Vascular Dementia. These cause the brain cells to degenerate and die quickly and the brain to shrink. A buildup of protein in the brain causes damage, which differs between each type of dementia.

Alzheimer’s brain damage causes the cerebral cortex to shrink. The cerebral cortex is responsible for memory and high functions. The proteins that build up are made of plaques and tangles, and the progressively build up and cause the loss of cells. This also inhibits the transfer of hormones that could be responsible for more cognitive function.

Frontotemporal Dementia is the shrinking and damage to the frontal lobe and the temporal lobe. This often occurs is those under 65.

Dementia with Lewy Bodies is the development of small circular lumps of protein in the cells of the brain, which is thought to inhibit hormones and neurotransmitters.

Vascular Dementia is when the blood flow to the brain is cut off, which causes the cells to die.

While there are no viable treatment options currently, there are treatments for specific symptoms of the disease. Most of them are temporary and their effectiveness is dependent on the individual.

Very few treatments are currently approved for use, and the risks for companies working in this line of research are huge, but the potential for success is also huge.

Simon Ridley, head of research at Alzheimer’s Research UK says “If the best chances of successful treatments are for early-stage disease patients, then these trials will be extremely long, A patent would have expired before a trial had finished. That’s why new models and approaches like adaptive licensing are needed. Currently, a trial has to show efficacy in cognition and daily living. These endpoints are not quick or easy to measure so perhaps a possibility is surrogate endpoints with conditional licences, almost like a Phase IV [post licensing] trial.”

As of now, companies have all focused on the protein’s building in the brain during Alzheimer’s, but a lot of their drugs have not passed clinical trials. Because there is so much not known about the disease, these trials are almost destined for failure – so research companies are starting to diversify their approaches.