Alzheimer's Disease

Alzheimer’s disease is a chronic neurodegenerative condition leading to rapid cognitive decline. ‘Cognition’ relates to how a person understands and acts in the world around them. Cognitive functions include memory, reasoning, awareness and decision-making, and to a large extent, influences our personality.

A gradual decline in cognitive function with age is normal, but in certain diseases, like Alzheimer’s, the decline begins earlier, and at a faster pace. The rapid cognitive decline can have a dramatic effect on a person’s ability to function in normal daily life, also affecting their family and the community around them.

Alzheimer’s disease is characterised by the presence of abnormal protein build-up in the brain, called amyloid plaques, with associated nerve cell degeneration and death, and loss of brain volume. It is not clear why these changes occur and what causes the rapid degeneration and death of the nerve cells. Unfortunately, the few drugs that are available to treat Alzheimer’s disease provide only a limited symptomatic benefit and do not slow down neurodegeneration.

As the leading cause of death in the UK, and second only to heart disease in Australia, Alzheimer’s disease is poised to become the next global public health crisis. There are almost 50 million Alzheimer’s disease sufferers world-wide and the number is set to double every 20 years. In the US alone, the cost of managing Alzheimer’s disease in 2013 was estimated at US$250bn, reaching US$1 trillion by 2050.

Alzheimer's disease is emerging as the most
significant health challenge of our time

Of the top ten fatal illnesses, Alzheimer’s disease remains the only one that cannot be prevented, treated or cured. None of the current treatment options provide much more than short-term relief of dementia symptoms, and significantly, none can slow the progression of the disease.  Alzheimer’s disease sufferers desperately need new alternative treatment options, and ideally, drugs with the potential to reverse the decline in brain function or to slow disease progression.

Alzheimer’s disease develops years before the symptoms of dementia appear. It is likely that brain pathology begins up to 15 years before the appearance of mild cognitive impairment or clinical dementia. Earlier diagnosis and treatment is therefore a vital hurdle to overcome before we see a significant reduction in the burden of this disease.

While no single clear cause for the development of Alzheimer’s disease has been reported, there is strong evidence to support an association between excess cortisol – the “stress hormone”- and the development of Alzheimer’s disease. Excess cortisol has been shown to cause cognitive decline, lead to β-amyloid plaque deposition and neurotoxicity in the brain, and loss of brain volume, all hallmarks of Alzheimer’s disease.

Actinogen Medical’s drug candidate Xanamem has been specifically designed to inhibit the production of cortisol in the brain by blocking the activity of a specific enzyme, 11β-HSD1. Blocking this enzyme prevents conversion of the inactive cortisone into the active cortisol.


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