GLP-1s May Reduce Cancer Risk in Diabetic Patients

A recent study has unveiled promising results for GLP-1 receptor agonists (RAs), showcasing their potential to reduce the risk of various cancers. Published in JAMA Network Open, the study analyzed the electronic health records of 113 million patients across the United States, focusing on nearly 1.7 million individuals using GLP-1 analogs for type 2 diabetes. Importantly, these patients had no prior history of obesity-associated cancers (OAC). The research compared these individuals to patients receiving insulin treatments.

Over a span of 15 years, the study found that GLP-1 receptor agonists significantly reduced the risk of 10 out of the 13 OACs examined. For instance, the likelihood of developing gallbladder cancer, meningioma, and pancreatic cancer was reduced by 65%, 63%, and 59%, respectively, compared to those treated with insulin. Additionally, the risk of ovarian cancer decreased by 48%, and hepatocellular carcinoma by 53%. Other cancers, including colorectal cancer, multiple myeloma, esophageal cancer, endometrial cancer, and kidney cancer, were also notably less frequent among patients on GLP-1 RAs.

Conversely, the study observed no significant impact of GLP-1 RAs on the occurrence of stomach cancer, thyroid cancer, and post-menopausal breast cancers. The researchers also compared the effectiveness of GLP-1 RAs with metformin, finding that while GLP-1 RAs were linked to a lowered risk of several cancers, these reductions did not achieve statistical significance. Notably, the risk of kidney cancer was 54% higher in patients using GLP-1 analogs compared to those on metformin.

“This study provides clinical data suggesting that GLP-1 RAs may reduce the risk of specific OACs compared with insulin,” the researchers noted, emphasizing that further studies are necessary to validate these findings. They highlighted that the retrospective observational nature of the study, relying on electronic health records, comes with inherent limitations, including potential biases and uncontrolled confounding factors. Despite efforts to control various variables, these limitations mean that no causal inferences can be definitively drawn from the current data.

The researchers called for long-term studies to better understand the impact of GLP-1 treatments on cancer risk, particularly concerning non-OACs and in comparison with other obesity treatments like bariatric surgery. Despite these challenges, the findings contribute to the expanding list of conditions that GLP-1 RAs could potentially address.

In March 2024, the FDA approved Novo Nordisk’s Wegovy (semaglutide) to reduce the risk of cardiovascular death, heart attack, and stroke in overweight or obese patients with cardiovascular disease. Additionally, Novo Nordisk is exploring semaglutide for diabetics with chronic kidney disease and reported in May 2024 that the therapy significantly lowered the risk of death in these patients.

Eli Lilly is also working to broaden the applications of its GLP-1 therapy, Zepbound (tirzepatide). The company recently shared data from the Phase III SURMOUNT-OSA trial, demonstrating that the drug significantly improves disease severity in patients with obstructive sleep apnea.

These advances underscore the growing therapeutic potential of GLP-1 receptor agonists beyond their established roles in managing obesity and diabetes. As further research and clinical trials continue, the full spectrum of benefits and risks associated with these treatments will become clearer, potentially offering new avenues for addressing multiple health conditions.