For years, treatment of Alzheimer’s disease focused on symptoms. New research targets the pathophysiological changes underneath — with potentially promising results.
Alzheimer’s disease (AD) is one of the greatest healthcare crises in our world today. According to the World Health Organization (WHO), there are 50 million people living with dementia today — and that number is predicted to increase to more than 80 million by 2030.
The good news is that promising investigational treatments are being researched. “In the past three decades, the scientific and medical community have made significant progress in understanding the biological mechanisms of the disease,” says Harald Hampel, M.D., Ph.D., chief medical officer and vice president at Eisai Inc. Dr. Hampel was recently named one of the top five global experts in Alzheimer’s disease.
That progress has changed our understanding of the disease from a symptom-based definition to one focused on changes in the brain that begin years before symptoms.
The cutting edge
That shift in focus is key. “Because current treatments target symptoms experienced in the late stages of dementia, Eisai has focused research on patients who are in the earlier stages of Alzheimer’s disease,” Dr. Hampel notes.
The key is the science of biomarkers, which measure physiological changes that occur when disease is present. These biomarkers are often detectable long before patients show symptoms. “Currently, there are well-validated neuroimaging and fluid biomarkers for Alzheimer’s disease,” says Dr. Hampel. The development of blood-based biomarkers has the potential to support large-scale screening for Alzheimer’s disease brain changes with a minimally invasive, widely accessible, easy-to-use and cost-effective test. This in turn would enable people to seek diagnosis and potential treatments long before they experience symptoms.
Biomarker research has led to what’s known as the AT(N) system, a classification scheme that categorizes individuals according to the presence of specific pathophysiological features of the disease. These are the Amyloid-β pathway (A), the aggregated tau or associated pathophysiology (T) and neuronal injury and neurodegeneration (N). These pathways (A, T and N) represent the core changes in the brain caused by Alzheimer’s disease that can be targeted by developing disease-modifying treatments.
This new understanding of the disease has led to the development of new ways to fight it. Eisai Inc. is conducting multiple clinical trials in pre-clinical, early and intermediate Alzheimer’s disease. Eisai and the National Institutes of Health-funded Alzheimer’s Clinical Trial Consortium have partnered on the phase III AHEAD 3-45 Study, which is testing an investigational treatment to see if it slows down the earliest changes that occur in the brain with Alzheimer’s disease. While Eisai’s phase III Clarity AD Study focuses on participants with early Alzheimer’s disease.
The fight against Alzheimer’s disease is everyone’s fight. That fight requires people — scientists, clinicians, patients and caregivers. Clinical trials involving them have been crucial to understanding Alzheimer’s disease — and they remain crucial for future breakthroughs.
“Clinical trials are important to show the efficacy and safety of potential new treatments for Alzheimer’s disease,” says Michael Irizarry, M.D., Master of Public Health and vice president of clinical research at Eisai Inc. “The trials can identify the individuals most likely to respond to treatments and how treatments impact disease progression, clinical symptoms, daily function, behavioral symptoms and quality of life.”
Patients, caregivers and family members can ask their physician about Alzheimer’s disease clinical trials or look to internet resources like the www.clinicaltrials.gov.
Dr. Hampel is optimistic about the future of Alzheimer’s disease treatments. “We are very excited about the research we are conducting,” he says, “our ultimate goal is a world without Alzheimer’s disease.”