Hyderabad: 21 September is observed as World Alzheimer’s Day as part of an international campaign to raise awareness about the disease that retards memory and other mental functions.
According to World Alzheimer’s Report 2015 by the non-profit organisation Alzheimer’s Disease International, it is estimated that 46 million people worldwide are affected by dementia; 4 million of them are said to be in India. Of all the known forms of dementia, Alzheimer’s is the most common.
And yet, despite its growing incidence, there is no cure for Alzheimer’s disease and treatment therapies available have little or no effect in stopping or reversing memory loss.
In countries like India, most people don’t even consider Alzheimer’s, named after the German doctor who first described it (Alois Alzheimer), a disease but symptoms associated with ageing, while some don’t talk about it fearing stigma.
Here are five things you need to know about Alzheimer’s disease.
So what is Alzheimer’s?
Alzheimer’s disease is one of the most widespread forms of dementia among the elderly. The disease affects the regions of brain, responsible for memory, thinking and speech. The most common early symptom of Alzheimer’s disease is loss of short-term memory or difficulty in remembering recent events.
What’s the disease mechanism of action and what causes Alzheimer’s?
In the brain, neurons or nerve cells connect and communicate at a synapse, a junction between two nerve cells, where tiny bursts of chemicals called neurotransmitters carry information from one cell to another. Alzheimer’s disrupts this process, and eventually destroys synapses and kills neurons, damaging the brain’s communication network. Scientists don’t yet fully understand the cause of Alzheimer’s but it is likely that the causes include some mix of genetic, environmental, and lifestyle factors.
What drugs are available to treat Alzheimer’s?
The drugs available in the market only treat the symptoms and not the underlying causes of the diseases. Some important drugs approved by the US Food and Drug Administration (USFDA) for Alzheirmer’s include donepezil, galantamine, memantine and rivastigmine. Most of the drugs are meant to slowing down damage to neurotransmitters.
What’s status of new drugs to treat Alzheimer’s? What are the challenges that researchers and companies face in developing drugs to treat the disease?
There are two challenges – one is scientific and the other is funding.
The scientific understanding of the disease is still evolving.
“While our understanding of Alzheimer’s has improved over the years with advancements being made in studying the disease, we still have a long way to go before we can offer much promise and hope to patients,” said Suneela Thatte, president of Indian Society for Clinical Research (ISCR).
The total number of active drugs in the Alzheimer’s treatment pipeline is relatively large at 583, implying a high-level of commercial interest after cancer and cardiac treatment.
However, attrition rate or failure rate of drugs is as high as 95%.
“A large number of clinical trials conducted in the AD market since 2006 yielded an extremely high failure rate across all phases of development: 44% for Phase I, 69% for Phase II and 76% for Phase III, with the latter having almost three times the rate of failure compared with the pharmaceutical industry as a whole,” said London-based business intelligence firm GBI Research in its latest report in February.
“We work on hypothesis, and we don’t have very good animal models compared to other diseases,” said J.B. Gupta, chief scientific officer at GVK Biosciences Pvt. Ltd, commenting on high failure rate of Alzheimer’s drugs.
Funding and getting volunteers for clinical trial is another problem.
According to Alzheimer’s Research UK, dementia research is hugely underfunded, especially when compared to other major diseases. They say it receives almost 10 times less funding than cancer research, for example.
The potential pay-off is huge due to ageing population.
The market for Alzheimer’s disease therapies expected to reach nearly $12 billion by 2023, according to healthcare research and analytics firm Decision Resources Group.
What is the doctor’s take on Alzheimer’s in India?
“One of the biggest challenges with dementia and Alzheimer’s is the social stigma attached to it. People either accept it as a normal part of ageing or are reluctant to talk about it,” says Shamsher Dwivedi, head and director, department of neurology, Fortis Memorial Research Institute, Gurgaon.
“We need more people to speak up about dementia as much as we need to build the capacity of the entire ecosystem to handle the growing burden of dementia,” Dwivedi said.
“Early detection and treatment of Alzheimer’s, will delay the onset of the disease,” said J. Mariano Anto Bruno Mascarenhas, a Chennai-based neurosurgeon.
Mascarenhas advised people with history of dementia or Alzheimer’s in their family and people with symptoms of memory loss and confusion, should get screened for the disease.