Aducanumab

Aducanumab is a potential new Alzheimer’s disease treatment which has had a whirlwind year – from the decision to discontinue global Phase III clinical trials for Alzheimer’s disease in March, to Biogen (USA) and Eisai (Japan) announcing in October that they will pursue regulatory approval for the drug. This change of direction for Aducanumad research, at least for Biogen, is due to analysis with a larger data set indicating that there was a reduction in clinical decline compared with the control group in one trial. This opens an exciting window of hope for the future of Alzheimer’s treatment if further trials are successful and regulatory approval is granted!

Biomarkers

2019 has been a good year for the investigation of blood biomarkers in neurological diseases, with a substantial increase in their use. For Alzheimer’s disease, a blood test was able to demonstrate 94% accuracy in diagnosis. This test detects levels of amyloid-βin the blood which can be used to predict protein accumulation in the brain, which contributes to the degeneration in Alzheimer’s disease. Whilst there is work still to be done to translate these blood biomarker tests into diagnostic functions, it is an encouraging start.

Blood Pressure

Scientists have known for a while that high blood pressure can contribute to increased dementia risk, however a recent study revealed that changes in the blood pressure of individuals as young as 36 years old could be linked to markers of poorer brain health. The research also mentioned that higher blood pressure at the age of 53, and quicker increases in blood pressure between the age of 43-53 were associated with more signs of ‘mini strokes’. Another study also reported that intensive blood pressure control may reduce age-related cognitive changes; this research helps us to better understand a risk factor of dementia and could encourage better monitoring of blood pressure earlier in life to reduce the risk of developing dementia later in life.

Cholesterol

One big finding in the field of dementia, specifically Alzheimer’s disease, this year was the finding that individuals with high levels of LDL cholesterol (one of two main types investigated) were more likely to develop early-onset Alzheimer’s disease, compared to people who had lower levels. This was also still true even when the researchers accounted for study participants with an APOE (Alzheimer’s risk gene) mutation. They further demonstrated that early-onset Alzheimer’s cases were higher in participants with a rare cholesterol metabolism mutation. This work shows the importance of being aware how our food choices may influence disease risk, as foods high in saturated and trans-saturated fats, found in red meats and full-fat dairy products, increase LDL cholesterol levels.

Diagnosis

Closely tied to the recent work into blood biomarkers as diagnostic tools for Alzheimer’s disease, a London-based company have created a new test for detecting dementia and Alzheimer’s disease by focusing on image cognition and the brain’s ability to analyse visual information. Using artificial intelligence, the company have produced an app which can determine whether a person has, or is at risk of developing, dementia in only five minutes. A separate group has also used an artificial intelligence-based technique to demonstrate how this, coupled with chemical analysis of blood samples, could speed up the diagnosis of brain tumours. Progress in diagnostics, especially methods which are minimally-invasive and provide quick results, could increase diagnosis rates and help provide earlier support to people with dementia.

Gender-Influenced Risk

Scientists have known for years that women have an increased risk of developing Alzheimer’s disease compared to men, however this difference is still not well understood. This year the Alzheimer’s Association International Conference reported gender-specific variations in the risk and progression of Alzheimer’s disease, including differences in the spread of toxic proteins in the brain, risk genes and the levels of glucose metabolism in the brain. There has also been published work about gender-specific differences in the gut bacteria in a mouse model of Alzheimer’s disease and how signs of dementia could be detected earlier in women by using new diagnostic criteria. Understanding the differences in dementia risk and implementing systems which better address this disparity will help improve the lives of people with dementia.

Oligomannate

Globally we have been waiting for a new drug approval to treat Alzheimer’s disease since 2003 and in November 2019 this changed. Green Valley Pharmaceuticals gained approval for Oligomannate as a new drug for the treatment of mild-to-moderate Alzheimer’s disease by China’s regulatory agency. The compound, which is derived from a type of algae, has been reported to work by decreasing inflammation in the brain by changing the bacteria present in the gut, where inflammation may start. There is some scepticism in the field about these results between scientists so it will be interesting to see how this research develops and if the results can be replicated elsewhere.

Umibecestat

Although there has been good news in the field of research for new Alzheimer’s treatments, not all findings have been positive. Two pivotal Phase II/III studies were discontinued for Umibecestat. An assessment of this drug identified worsening in some measures of cognitive function which lead to the collection decision between three groups who concluded that the potential benefit for study participants did not outweigh the risk. Unfortunately removes a potential treatment from the future market, however the advances with Aducanumab and Oligomannate are encouraging so hope for future treatments should continue.

World Health Organisation

The World Health Organisation (WHO) launched their first ever guidelines for reducing the risk of dementia in May, providing a knowledge base for healthcare providers to advise patients on what they can do to help prevent cognitive decline and dementia. These new guidelines should help provide better education about reducing dementia risk, which may in the future result in a reduction of diagnoses if modifiable risk factors are better managed with this increased awareness.

Jennifer Pinnell