A breakthrough weight loss injection, Liraglutide, sold under the brand name Saxenda and already prescribed to thousands of NHS patients, shows promising research suggesting it could significantly reduce the risk of developing Alzheimer's disease. This once-a-day injectable medication, part of a class known as GLP-1 agonists, is typically offered to individuals with a BMI over 30 to improve blood sugar control and assist with weight loss. It functions similarly to semaglutide, the active ingredient in Ozempic and Wegovy, by modulating metabolism to induce feelings of fullness and reduce hunger.

Leading British experts now suggest that Liraglutide could effectively slow cognitive decline and brain cell loss in Alzheimer's patients by as much as 50 percent. Researchers from Imperial College London, led by neuroscience expert Professor Paul Edison, stated these findings represent "some of the strongest evidence to date" that weight loss jabs might aid in managing the condition, potentially paving the way for innovative dementia treatments. This revelation contrasts with recent trial results for semaglutide, which failed to demonstrate a statistically significant benefit in slowing Alzheimer's progression, leading to a 12 percent drop in the share value of its manufacturer, Novo Nordisk.

Professor Edison emphasized the significance of the findings: "Our findings provide some of the strongest evidence yet that GLP-1 treatments could modify the disease process in Alzheimer's disease." He added that Liraglutide has shown encouraging effects on brain structure and cognitive decline in their Phase 2b trial, setting the stage for a comprehensive Phase 3 program. A major advantage is the ability to repurpose an existing drug with established safety data, which could significantly accelerate its adoption for Alzheimer’s compared to developing an entirely new therapy. Furthermore, this trial tests a distinct therapeutic approach for Alzheimer's that does not solely rely on amyloid-targeting strategies.

The Phase 2b study involved 169 individuals, with an average age of 71, diagnosed with mild to moderate Alzheimer's disease. Participants were divided into two groups: 72 received Liraglutide, while 82 received a placebo. Over a one-year follow-up, brain scans revealed that Liraglutide slowed brain volume loss by approximately half compared to the placebo group and demonstrated an 18 percent more beneficial effect on cognition. However, the drug did not prevent the decline of brain glucose metabolism.

While the exact mechanism for Liraglutide’s effects was not fully determined, researchers noted previous studies indicating its ability to reduce neuroinflammation and tau protein accumulation. Aggregations of tau, along with amyloid, form plaques and tangles that are widely believed to underpin Alzheimer’s symptoms, the leading cause of dementia. Published in Nature Medicine, the study acknowledged the 12-month duration as a limitation for confirming long-term benefits but affirmed that it provides meaningful insights for further research.

Saxenda is currently available on the NHS for weight loss, typically prescribed after a referral to a specialist weight management service. Common side effects include aches and pains, diarrhea, fever, frequent urination, and difficulty sleeping. Trials have shown that users lose an average of 6.4 percent of body weight over 68 weeks. Dementia affects approximately 944,000 people in the UK and around 7 million in the US, with Alzheimer's accounting for six out of ten dementia cases. Early symptoms include memory issues, difficulties with thinking and reasoning, and language problems, which progressively worsen over time.

Dr. Richard Oakley, Associate Director of Research and Innovation at Alzheimer’s Society, expressed satisfaction with co-funding the ELAD trial, acknowledging its interesting insights into Liraglutide’s potential. However, he highlighted the contrasting results from a Phase 3 trial of semaglutide, which did not show reduced cognitive decline in early Alzheimer’s patients. Dr. Oakley emphasized the critical need to investigate these drugs in individuals at risk of Alzheimer’s before symptoms appear. He reiterated the Alzheimer’s Society’s commitment to supporting cutting-edge research to drive change for everyone impacted by dementia, noting that one in three people will develop dementia in their lifetime. Dementia was reported as the UK's leading cause of death in 2022, with 74,261 fatalities, up from 69,178 the previous year.