GLP-1 drugs may help lower mortality risk in colon cancer patients

New research suggests that drugs in the GLP-1 class may significantly reduce the five-year mortality risk for people diagnosed with colon cancer.

The study, which analysed medical records from more than 6,800 adults with an average age of around 71, drew on data from the University of California Health Data Warehouse. Of the 6,871 patients included, 103 had been prescribed GLP-1 receptor agonists.

Dr Cuomo, one of the study’s authors, said colon cancer outcomes are “tightly coupled to metabolic dysregulation and obesity”, adding that GLP-1 receptor agonists act directly on the pathways involved. He noted that clinical evidence to date has been “limited and heterogeneous”, leaving a “clear knowledge gap despite strong biological plausibility”.

According to the analysis, patients taking GLP-1 medications had a five-year mortality risk of 15.5 per cent, compared with 37.1 per cent among those not receiving the drugs. “The difference in mortality signals a potentially meaningful survival advantage for GLP-1 users,” Dr Cuomo said. He added that the association “persisted after propensity matching and multivariable adjustment” and remained consistent across varying levels of disease severity.

He noted that the greatest effects were observed in people with a body mass index of 35 or more. This, he said, suggests the benefit may arise from reducing the adverse physiological effects associated with severe obesity.

Discussing possible mechanisms, Dr Cuomo said the same biological pathways that influence outcomes after diagnosis may also reduce cancer development or progression. GLP-1 receptor agonists improve insulin sensitivity, reduce systemic inflammation and may modulate the tumour microenvironment, mechanisms linked in preclinical research to slower cancer growth.

He outlined several next steps for research, including a randomised controlled trial evaluating GLP-1 agonists alongside standard colon cancer treatments and prospective studies with detailed clinical, genetic and patient-reported data to identify which groups might benefit most. Mechanistic investigations into inflammatory signalling and insulin-related pathways are also planned.

Dr Anton Bilchik, a surgical oncologist at Providence Saint John’s Cancer Institute in California who was not involved in the study, described the findings as highly significant. He noted that while GLP-1 agonists are known for their effects on weight loss, they may also offer direct anticancer benefits.

“These drugs may impact the immune microenvironment, the microbiome and may have anti-inflammatory properties,” he said. “All of these have been hypothesised as possible contributors to cancers such as colon cancer.”

Dr Bilchik added that GLP-1 drugs, initially introduced for weight management, are now being explored for potential roles in cardiovascular disease and cancer treatment. He suggested their eventual clinical use could extend far beyond their original purpose.