Weight-loss injections known as GLP-1 receptor agonists could nearly halve the risk of obesity-related cancers, according to new research presented at the European Congress on Obesity in Malaga, Spain, and published in the journal eClinicalMedicine. The study indicates that these medications may offer anti-cancer benefits beyond their role in weight reduction.
Researchers analyzed electronic health record data for 6,356 adults aged 24 years or older with obesity and type 2 diabetes who had no prior history of cancer. The participants were treated with either first-generation GLP-1 receptor agonists or underwent bariatric surgery. The patients were matched 1:1 based on sex, age, body mass index (BMI) at the start of the study, time of treatment initiation, and smoking status.
Over a median follow-up period of 7.5 years, 298 participants were diagnosed with obesity-related cancers. Specifically, 150 cases occurred among the 3,178 patients who had bariatric surgery, and 148 cases were identified among the 3,178 patients treated with GLP-1 receptor agonists. These findings suggest that the rates of obesity-related cancer were similar between the two groups, despite the known relative advantage of bariatric surgery in weight reduction.
Further analysis revealed that after accounting for the relative advantage of surgery in reducing weight, GLP-1 receptor agonists were associated with a 41% lower risk of obesity-related cancer compared to bariatric surgery. "We found a direct effect of GLP-1 receptor agonists beyond weight loss," said Dr. Yael Wolff Sagy, co-lead author of the study from Clalit Health Services in Tel-Aviv, Israel, according to The Independent. "They are 41 percent more effective at preventing obesity-related cancer," she added.
The study suggests that GLP-1 receptor agonists may have anti-cancer properties independent of their weight-loss effects. "The protective effects of GLP-1 receptor agonists against obesity-related cancers likely arise from multiple mechanisms, including reducing inflammation," said Professor Dror Dicker from Hasharon Hospital, Rabin Medical Centre in Israel, co-lead author of the study, as reported by The Independent. He added, "Our study is unique in that the long-term follow-up allowed us to compare the effects of GLP-1 receptor agonists and surgery with potential long latency periods of cancer."
Experts emphasize the potential of these findings for cancer prevention. "While this was an observational study and caution was needed interpreting the results, the results were very exciting," said Professor Mark Lawler from Queen's University Belfast, according to The Guardian. "We already know bariatric surgery cuts obesity-related cancer risk by about a third; these data suggest target GLP-1s may cut that risk by nearly 50%—an approach that would be transformational in preventing obesity-related cancer," he noted.
A team of 54 international experts from 12 different countries issued a joint statement at the European Congress on Obesity, calling for weight-loss drugs such as Wegovy and Mounjaro to be trialed as a priority for cancer prevention. A team based at the University of Manchester, funded by Cancer Research UK, is designing a clinical trial involving tens of thousands of patients, which they hope to start within "three to five years."
"Prevention is really important in cancer, especially now we have a weapon to potentially reduce one of the major risk factors, in obesity," said Dr. Matthew Harris of the Manchester Cancer Research Centre, as reported by The Guardian.
GLP-1 receptor agonists, including medications such as semaglutide (marketed as Wegovy and Ozempic) and liraglutide (marketed as Saxenda), are currently prescribed for weight loss and type 2 diabetes. These injections curb hunger pangs by mimicking the glucagon-like peptide 1 (GLP-1) hormone, which regulates feelings of fullness and lowers blood sugar levels. These drugs are available through the NHS for those with a high BMI and can also be obtained privately.
Obesity and diabetes are linked with an increased risk for many types of cancer, referred to as obesity-related cancers, with obesity associated with 13 different cancers. Being overweight or obese is the second biggest cause of cancer in the UK, causing more than one in 20 cancer cases. The risk of cancer is higher the more overweight people are and the longer they have been overweight.
"This study, whilst interesting, cannot confirm or refute any links of incretin-based therapies with cancer as the design was not a trial but rather observational, and there were quite marked differences between the groups in baseline characteristics that simply cannot be matched," said Naveed Sattar, professor of cardiometabolic medicine at the University of Glasgow, according to The Independent. He added, "Larger trials are needed to understand links between such medicines and cancer risks, and several should report over the next five years."
The authors of the study agree that future randomized trials and larger prospective studies are needed to confirm the effects and explore the underlying mechanisms. "New generation, highly potent GLP-1 receptor agonists with higher efficacy in weight reduction may convey an even greater advantage in reducing the risk of obesity-related cancers, but future research is needed to make sure that these drugs do not increase the risk for non-obesity-related cancers," said Professor Dror Dicker, as reported by The Independent.
Researchers and cancer experts are hopeful that GLP-1 receptor agonists could play a role in cancer prevention. "This work could herald a whole new era of preventative cancer medicine," said Professor Mark Lawler, according to The Guardian. He added, "Biologically, this makes sense, as targeting GLP-1 dampens down inflammation, one of the hallmarks of cancer."
"Weight-loss jabs provide genuinely fantastic weight loss and may offer a population-scale intervention for obesity-related cancers," said Dr. Matthew Harris, as reported by The Mirror. He emphasized the potential impact on public health, suggesting that these medications could be a "genuinely promising possible option for cancer prevention in the future."
The article was written with the assistance of a news analysis system.