A new study provides real-world evidence to support the potential repurposing of glucagon-like peptide 1 receptor agonists (GLP-1 RAs), used to treat type 2 diabetes and obesity, for prevention of Alzheimer’s disease (AD). 

Adults with type 2 diabetes who were prescribed the GLP-1 RA semaglutide had a significantly lower risk for AD compared with their peers who were prescribed any of seven other antidiabetic medications, including other types of GLP-1 receptor–targeting medications. 

“These findings support further clinical trials to assess semaglutide’s potential in delaying or preventing AD,” the investigators, led by Rong Xu, PhD, with Case Western Reserve School of Medicine, Cleveland, Ohio, write. 

The study was published online on October 24 in Alzheimer’s & Dementia.

Real-World Data

Semaglutide has shown neuroprotective effects in animal models of neurodegenerative diseases, including AD and Parkinson’s disease. In animal models of AD, the drug reduced beta-amyloid deposition and improved spatial learning and memory, as well as glucose metabolism in the brain. 

In a real-world analysis, Xu and colleagues used electronic health record data to identify 17,104 new users of semaglutide and 1,077,657 new users of seven other antidiabetic medications, including other GLP-1 RAs, insulin, metformin, dipeptidyl peptidase 4 inhibitors, sodium-glucose cotransporter 2 inhibitors, sulfonylurea, and thiazolidinedione.

Over 3 years, treatment with semaglutide was associated with significantly reduced risk of developing AD, most strongly compared with insulin (hazard ratio [HR], 0.33) and most weakly compared with other GLP-1 RAs (HR, 0.59). 

Compared with the other medications, semaglutide was associated with a 40%-70% reduced risk for first-time diagnosis of AD in patients with type 2 diabetes, with similar reductions seen across obesity status and gender and age groups, the authors reported. 

The findings align with recent evidence suggesting GLP-1 RAs may protect cognitive function. 

For example, as previously reported by Medscape Medical News, in the phase 2b ELAD clinical trial, adults with early-stage AD taking the GLP-1 RA liraglutide exhibited slower decline in memory and thinking and experienced less brain atrophy over 12 months compared with placebo. 

Promising, but Preliminary 

Reached for comment, Courtney Kloske, PhD, Alzheimer’s Association director of scientific engagement, noted that diabetes is a known risk factor for AD and managing diabetes with drugs such as semaglutide “could benefit brain health simply by managing diabetes.”

“However, we still need large clinical trials in representative populations to determine if semaglutide specifically lowers the risk of Alzheimer’s, so it is too early to recommend it for prevention,” Kloske told Medscape Medical News. 

She noted that some research suggests that GLP-1 RAs “may help reduce inflammation and positively impact brain energy use. However, more research is needed to fully understand how these processes might contribute to preventing cognitive decline or Alzheimer’s,” Kloske cautioned. 

The Alzheimer’s Association’s “Part the Cloud” initiative has invested more than $68 million to advance 65 clinical trials targeting a variety of compounds, including repurposed drugs that may address known and potential new aspects of the disease, Kloske said. 

The study was supported by grants from the National Institute on Aging and the National Center for Advancing Translational Sciences. Xu and Kloske have no relevant conflicts.