Weight-loss jab found to slow progression of Alzheimer's disease in huge breakthrough

Doctors often offer patients with a BMI over 30 a drug known as Liraglutide — sold under the brand name Saxenda.

The jab has been shown to improve blood sugar control and help people shed the pounds, similar to better known brands such as Ozempic and Wegovy. 

But experts say the injections could also slow cognitive decline and brain cell loss in Alzheimer's patients by up to 50 per cent following a landmark study. 

In the study, 169 people with mild to moderate Alzheimer's disease, aged 71 on average, were divided into two groups.

Nearly half (72) took liraglutide, while the remaining 82 patients took a placebo. 

Over the course of a year, multiple brain scans revealed liraglutide slowed brain volume loss by around half compared to patients taking the placebo. 

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Researchers say the findings offer strong evidence that weight loss injections may help those with the condition and could pave the way for new treatments in the field.

Professor Paul Edison, a neuroscience expert at Imperial College London, who led the study, said: “Our findings provide some of the strongest evidence yet that GLP-1 treatments could modify the disease process in Alzheimer's disease.

“Liraglutide has shown encouraging effects on brain structure and slowing of cognitive decline in our Phase 2b trial, and this has paved the way for a Phase 3 programme.

“Because this drug is already approved for diabetes, advancing it for Alzheimer's disease could be significantly faster than developing a new therapy from scratch.”

He added that advancing the drug for Alzheimer's disease could be “significantly faster than developing a new therapy from scratch” as it is already used to treat patients with diabetes.

“The ability to repurpose a drug with good safety data is a major advantage. We are not starting from zero.

“This trial is important because it tests a completely different therapeutic strategy in Alzheimer's disease—one that does not rely solely on amyloid,” Prof Edison said. 

This is not the first time weight-loss jabs have been touted to come with other benefits. 

The injections, also known as GLP-1 receptor agonists, work by reducing food cravings and are available on the NHS for people with a high BMI, or via private providers.

Major names of GLP-1 receptor agonists, some of which are used to treat diabetes, include semaglutide (Wegovy and Ozempic), tirzepatide (Mounjaro), liraglutide (Saxenda) and exenatide (a drug which has now been discontinued).

Research published in the journal eClinicalMedicine in May found that first generation GLP-1 receptor agonists such as liraglutide and exenatide may also have anti-cancer benefits beyond weight loss.

Researchers first of all discovered similar rates of obesity-related cancer among patients treated with the drugs and those given bariatric surgery.

Co-lead author, Dr Yael Wolff Sagy from Clalit Health Services in Tel-Aviv, Israel, said they also found a "direct effect" of GLP-1 receptor agonists beyond weight-loss "to be 41% more effective at preventing obesity-related cancer".

She added: "We do not yet fully understand how GLP-1s work, but this study adds to the growing evidence showing that weight loss alone cannot completely account for the metabolic, anti-cancer, and many other benefits that these medications provide."