Weight-loss drug may slow cognitive decline in Alzheimer’s, study finds

A small study shows that a weight loss drug may slow the loss of brain volume in people with Alzheimer’s disease.

Liraglutide, which can also be prescribed for diabetes, is usually given as a once-daily injection.

Research findings published at the Alzheimer’s Association International Conference in the US show that the drug, also known as Saxenda, can slow the decline of memory and thinking skills in people with the disease.

The number of people with dementia worldwide is expected to almost triple to 153 million by 2050, posing a rapidly growing threat to future health and social care systems, experts say.

“This research offers hope that there are more options to change the course of the disease,” said Alzheimer’s Association Chief Science Officer Dr. Maria Carrillo. “We are in an era of unprecedented promise, with new treatments in various stages of development that could slow or potentially prevent cognitive decline due to Alzheimer’s.”

The trial looked at 204 patients in the UK. Half were given liraglutide, made by Novo Nordisk, and the other half were given a placebo.

The study did not meet its primary endpoint, or main objective, which was change in cerebral glucose metabolism, an assessment of brain function.

It did meet secondary endpoints. The drug appeared to reduce shrinkage in the parts of the brain that control memory, learning, language and decision-making by almost 50% compared with placebo.

Researchers led by experts from Imperial College London found that after 12 months of treatment, the drug appeared to reduce cognitive decline in participants by as much as 18%.

Tests of memory, comprehension, language and spatial orientation found that those who took the drug experienced a “statistically significant slowing of cognitive decline” after a year, compared with those who received the placebo drug.

Experts say much larger studies are needed to confirm the findings.

Study leader Paul Edison, professor of science at Imperial College London, said: “The slower loss of brain volume suggests that liraglutide protects the brain, much like statins protect the heart.

“Although more research is needed, liraglutide may work through several mechanisms, such as reducing inflammation in the brain, lowering insulin resistance and the toxic effects of the Alzheimer’s biomarkers amyloid-beta and tau, and improving how nerve cells in the brain communicate.”

Dr Sheona Scales, director of research at Alzheimer’s Research UK, said: “If we can repurpose medicines that are already licensed for other conditions, it could accelerate progress and provide new options for preventing or treating dementia-causing diseases such as Alzheimer’s.

“This new research shows that people with early-stage Alzheimer’s who took liraglutide had a slower decline in memory and thinking skills, and less brain shrinkage, over 12 months, compared with placebo.

“However, the study was conducted on a small group of people. Larger studies are now underway to see if drugs such as liraglutide are effective in slowing the progression of Alzheimer’s disease.”

The trial was not sponsored by Novo Nordisk. However, the company is testing another weight-loss drug, semaglutide—sold as the diabetes drug Ozempic and the obesity drug Wegovy—in thousands of patients with early Alzheimer’s.

The two trials started in 2021 and results are expected in 2025.