Major trial launched to explore GLP-1 benefit in dementia

A large-scale trial has been launched, with $100 million in backing, to explore whether lifestyle changes coupled with GLP-1 agonists or similar incretin therapies can reduce the risk of dementia.

The three-year PROTECT-Cog study, announced at the 2026 Alzheimer's Association International Congress (AAIC) in London, UK, today, is drawing on earlier study results showing that lifestyle changes can help improve memory, thinking, and overall cognitive function.

The US POINTER and LatAm-FINGERS trials showed that a highly structured lifestyle programme of diet, exercise, cardiovascular health monitoring, and brain-training exercises was more effective than self-guided, flexible changes at improving global cognition scores in adults at risk of cognitive decline and dementia.

In US POINTER, the improvements were equivalent to approximately one to two years of cognitive advantage, which came alongside other benefits, including reducing frailty and sleep apnoea and improving blood pressure control.

The hope is that adding in a GLP-1 agonist or similarly-acting drug – such as Novo Nordisk's semaglutide or Eli Lilly's tirzepatide, used to treat diabetes and for weight loss – will enhance the effect of the lifestyle changes.

Various retrospective studies have pointed to a protective effect of GLP-1 agonists in dementia, with some showing improvements of 40% to 70% compared to other drugs used to treat diabetes, but the new study offers an opportunity to test that hypothesis prospectively.

"PROTECT-Cog builds directly on what we learned from US POINTER and takes the next critical step in prevention science," said Dr Maria Carrillo, chief science officer and medical affairs lead at the Alzheimer's Association, and principal investigator of the new study.

"By testing a combined approach that targets both lifestyle and biology, we have the opportunity to better understand how to meaningfully reduce the risk of cognitive decline before symptoms begin," she added.

PROTECT-Cog will enrol older adults who are at increased risk for cognitive decline and compare two structured lifestyle change programmes – one intensive and the other a slightly less rigid version – with and without drug treatment.

Earlier this month, a study published in The Lancet Healthy Longevity suggested that 45% of all cases of dementia are avoidable with lifestyle changes.

UK registry study launched

Also this week, the UK has launched a nationwide, virtual registry of people living with dementia in the hope of using it as a resource to find new treatments, according to the Financial Times.

The BARBARA registry – an acronym for Brain Ageing Registry for Biomarkers, Access to trials, Research, and Adoption – will bring together 180 existing research databases or population health studies in order to improve access to clinical trials, said the report. It is being run as part of the Dame Barbara Windsor Dementia Goals programme, and is named after the beloved actress who developed Alzheimer's and died in 2020.

Funding for the project is being provided by the UK government, philanthropic foundations, and the pharma industry.