ASCO 25: Can GLP-1 drugs reduce cancer risk?
A new study has suggested the benefits of GLP-1 agonists could extend to a reduction in the risk of a slew of cancers associated with being overweight.
The observational study of more than 170,000 people with diabetes and obesity in the US, drawing on data from health records, showed that a group of 14 obesity-associated cancers (OACs) were less likely to be diagnosed in people taking GLP-1 agonists than a group taking DPP4 inhibitors, an older class of diabetes medication.
All told, who took GLP-1 receptor agonists had a 7% lower risk of developing an OAC – which include cancers of the oesophagus, colon, rectum, stomach, liver, gallbladder, pancreas, kidney, post-menopausal breast, ovary, endometrium and thyroid, as well as multiple myeloma and meningiomas – compared to those taking a DPP-4 inhibitor.
There was also an 8% lower risk of death from any cause among patients taking GLP-1 drugs like Novo Nordisk's Ozempic (semaglutide) and Eli Lilly's Trulicity (dulaglutide) for diabetes and Novo Nordisk's Wegovy (semaglutide) for obesity, compared to the control arm.
The study looked at data over a 10-year period between 2013 and 2023 from people with a body mass index (BMI) of 30 kg/m2 or more – putting them into the obese category – as well as a diagnosis of type 2 diabetes. The average follow-up period was around four years.
The results tie in with another observational study published last year, which carried out a similar analysis among 1.6 million people with type 2 diabetes who were prescribed either GLP-1 drugs, insulin or metformin, and also found a reduction across 13 different OACs.
The prospect of reducing the risk of some very common cancers adds the weight of evidence behind the GLP-1 agonist class, members of which have now been approved for diabetes, obesity, cardiovascular risk reduction in people who are overweight with underlying risk factors, and obstructive sleep apnoea.
Intriguingly, the benefits seen with GLP-1s in both OACs and overall mortality were seen in women, but not men. Among female patients, the reduction in OACs was 8%, while all-cause death was 20% lower than with DPP-4 inhibitors.
"Although obesity is now recognised as an increasingly important cause of cancer in the US and worldwide, no medications have been proven to lower the cancer risk associated with obesity," commented lead study author Lucas Mavromatis of NYU Grossman School of Medicine.
"Our study begins to fill that gap by evaluating GLP-1 receptor agonists, a relatively new but widely prescribed medication that treats diabetes, obesity, and related conditions," he added. By some estimates, around 12% of people in the US have been prescribed one of these drugs at some point.
"Our results suggest they may modestly cut the chance of developing certain cancers—especially cancers of the colon and rectum—and reduce rates of death due to all causes," continued Mavromatis.
"These data are reassuring, but more studies are required to prove causation."
The data were revealed in advance of this year's annual ASCO cancer congress, which starts on Friday.
"I see many patients with obesity, and given the clear link between cancer and obesity, defining the clinical role of GLP-1 medications in cancer prevention is important," commented ASCO President Robin Zon.
"Though this trial does not establish causation, it hints that these drugs might have a preventative effect," he added. "Future research is needed to validate these findings, including in patients who do not have diabetes."
