Alzheimer’s disease (AD) is a devastating neurodegenerative disease of the central nervous system which is responsible for 60-80% of all cases of dementia and progressively destroys the cognitive abilities of its victims.
Very early AD
Mild to moderate AD
As Alzheimer’s disease progresses, neurofibrillary tangles spread throughout the brain (shown in blue). Plaques also spread throughout the brain, starting in the neocortex. By the final stage, damage is wide spread and brain tissue has shrunk significantly.
Alzheimer’s is one of the biggest burdens of society with a dramatic and growing worldwide incidence rate of one new case every three seconds, or 9.9 million new cases of dementia each year. Since the incidence and prevalence of AD increase with age, the number of patients will grow significantly as society gets older. Worldwide in 2015 there are 46.8 million people living with dementia and by 2050 it is expected that global patient numbers will triple to 131.5 million. It is estimated that the annual societal and economic cost of dementia has risen from US$ 604 billion in 2010 to US$ 818 billion in 2015. In the US, AD is now the 6th leading cause of death across all ages and is the fifth leading cause of death for those aged 65 and older.
It is becoming increasingly clear that AD develops because of a complex series of events that take place in the brain over a long period of time. Two proteins - Tau and beta-amyloid (Abeta) - are recognized as major hallmarks of neurodegeneration: tangles and other abnormal forms of Tau protein accumulate inside the brain cells and spread between cells, while plaques and oligomers formed by Abeta occur outside the brain cells of people with Alzheimer’s.
Today though, AD is typically diagnosed by neurologists and psychiatrists through a series of cognitive and functioning tests once symptoms are already clinically present. This results in a diagnosis at later stages of the disease where irreversible loss of neurons has already occurred. An early diagnosis with imaging methods and biomarkers is therefore crucial and is expected to translate into earlier treatment with better outcome for the patients and offer the possibility to look into disease prevention.
Currently approved treatments only include medications that help relieve the symptoms of the disease but do not treat the underlying causes of the disease. The clinical benefit derived is typically incomplete and only improves the patient’s symptoms for a short period of time underlining the urgent medical need of disease modifying treatments. Such disease modifying treatments are expected to have a major impact for the patients as they will considerably slow the cognitive decline. The benefit for the patients will increase if the treatment can start earlier in the disease course, ideally even before symptoms start to appear.
AC Immune’s therapeutic and diagnostic agents are at the forefront of fighting against one of the world’s greatest healthcare challenges – the need to develop reliable and accurate diagnostics and disease modifying treatments to improve the lives of patients suffering from Alzheimer’s and other neurodegenerative diseases.