Renewed hope for diagnosis and treatment of Alzheimer’s disease
Dr. Sharon Cohen, neurologist and medical director of the Toronto Memory Program, has experienced the disappointment that comes from studying a potential new therapy for Alzheimer’s disease that ultimately proves unsuccessful.
“I’ve been involved in several clinical trials, and it’s devastating to build your team and nurture participants through the process, only to have it end in failure,” she says.
“But the landscape is changing, and we are starting 2020 with many good reasons to be hopeful.”
While failure is part of the drug development process, research into Alzheimer’s disease has been particularly difficult, with a failure rate in clinical trials exceeding 99 per cent. In the 20-year period ending in 2017, there were 146 failed efforts.*
Disappointment is now making way for a new sense of optimism, with a high level of promising research activity into disease-modifying therapies and diagnostic options.
“A significant drawback in previous trials was that interventions were applied too late – after too much impairment had occurred – because we didn’t know how to identify early Alzheimer’s disease, says Dr. Cohen.
“But recently, we gained a greater ability to look at the underlying biological changes in the brain and to detect amyloid and tau proteins associated with the disease, even before cognitive symptoms appear,” she explains.
Earlier stages of Alzheimer’s disease can now be diagnosed through positron emission tomography (PET) brain scans or by analyzing a sample of spinal fluid. At the same time, research is underway into easier, less costly diagnostic tools, including an eye exam with a hyperspectral retina camera being developed by Retispec, a Canadian medical imaging company, and a blood test, which Dr. Cohen says could be available within the next two to five years. There is also a clinic-based genetic test being developed by Spartan Bio, another innovative Canadian company, which can confirm presence of ApoE – a gene which puts its carriers at a higher risk for Alzheimer’s disease – within 60 minutes.
Several new drug compounds for treatment are progressing in the development pipeline, she says. Knowledge is building on numerous approaches to treatment – with studies targeting different mechanisms understood to contribute to the disease’s debilitating symptoms. Research is also underway into vaccines against Alzheimer’s disease.
The Alzheimer Society of Canada is also encouraged to see this new era of progress, says Nalini Sen, director of research and knowledge translation and exchange (KTE). The Society has to date invested more than $59-million into initiatives by Canadian researchers in areas that include medical research, health policy change and community supports for people living with the disease.
“This year, we have added new funding opportunities to encourage more innovation, including by supporting early-career investigators leading high-risk and novel research projects,” says Sen.
Another key advance is the growing body of research showing how lifestyle factors can help reduce the risk of developing dementias, she says.
“It’s estimated that up to half of cases of Alzheimer’s disease in the world may be as a result of modifiable risk factors, such as diabetes or high blood pressure, obesity or smoking and physical inactivity. We have made great strides in Alzheimer’s research to date as we now know that healthy lifestyle choices such as physical activity and healthy diet can help us maintain brain function and, in some cases, reverse that decline.”
Another welcome step was the Government of Canada’s June 2019 release of the country’s first-ever national dementia strategy: A Dementia Strategy for Canada: Together We Aspire. The strategy includes a federal commitment to invest up to $50-million over five years in three key areas: prevention, advancing therapies/finding a cure and improving quality of life for individuals with Alzheimer’s disease.
“The Alzheimer Society has been advocating for this strategy for well over a decade,” Sen says. “However, the journey isn’t over. Full funding is urgently needed to implement the strategy.”
Dr. Cohen agrees that funding is critical, along with major changes to Canadian health-care infrastructure to ensure people can gain timely access to diagnosis and treatment as early as possible.
“Most memory clinics already have a wait list of at least a year, and that is tragic,” she says. “As we acquire more diagnostic tools and therapies, we will need significantly more resources to help prevent progression of Alzheimer’s disease.”
Supported by Biogen Canada
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