New Delhi, May 23 -- GLP-1 inhibitors, a class of diabetes and weight-loss drugs already credited with reducing the risk of heart attacks and strokes, may also slow the spread of certain cancers, according to a large real-world study presented at an American oncology conference in Chicago on Friday. According to a press release by the American Society of Clinical Oncology (ASCO), researchers at Cleveland Clinic's Taussig Cancer Institute examined health records of over 10,000 patients with early-to-mid-stage cancer who had begun taking GLP-1 receptor agonists - drugs that mimic a gut hormone called glucagon-like peptide-1, which regulates blood sugar and appetite - after cancer diagnosis. They compared this group against patients taking DPP-4 inhibitors, a different class of diabetes drug that works less potently through a related pathway. Across seven cancer types, patients on GLP-1 drugs were less likely to progress to stage IV - or metastatic - disease in six. The difference was statistically significant, meaning unlikely to be due to chance, in four: non-small cell lung cancer, breast, colorectal, and hepatocellular, or liver, cancer. Patients with lung cancer on GLP-1 drugs progressed to stage IV at roughly half the rate of the comparison group - 10% against 22.3%. In breast cancer, the figures were 10.2% against 20.1%. The study used propensity matching - a technique that attempts to make the two groups comparable by controlling for factors including age, weight, smoking history, other illnesses, and cancer treatments received, so that the comparison is not skewed by pre-existing differences between patients - to reduce the risk that the findings simply reflect that healthier patients were more likely to be prescribed GLP-1 drugs. The results are corroborated by a separate line of evidence. When the researchers analysed data from the Cancer Genome Atlas - a repository of tumour genetic data - they found cancers with higher expression of GLP-1 receptor on their surface were associated with a 33% lower risk of death overall, and 45% lower in breast cancer. That biological signal suggests the drugs may be acting on cancer cells directly, not merely through the indirect route of weight loss and metabolic improvement - which too are independently linked as factors helping slow cancer spread. "GLP-1 receptor agonists have never been just glucose-lowering drugs," said Dr Marcin Chwistek, chief of supportive oncology and palliative care at Fox Chase Cancer Center and an ASCO expert. "What's new here is the consistency across tumour types, and data this large and this consistent warrant a prospective randomized trial." Other recent research points in the same direction, Wall Street Journal reported on Friday. An MD Anderson Cancer Center analysis of more than 137,000 breast cancer patients found that over 95% of GLP-1 users were alive after five years, compared with 89.5% for non-users. A separate University of Pennsylvania study of nearly 95,000 women found those who had taken a GLP-1 drug were about 25% less likely to be diagnosed with breast cancer at all. The Cleveland study findings carry crucial caveats - it identifies associations in real-world patient data rather than establishing cause and effect through controlled experimentation - and has not yet been peer-reviewed. Scientists also do not yet know whether any protective effect works through weight loss and metabolic improvement, or through a more direct action on tumour biology, since effects on cancer have not typically been studied in the context of these drugs. The drugs - which include semaglutide, sold as Ozempic and Wegovy by Novo Nordisk, and tirzepatide, sold as Mounjaro by Eli Lilly - are already reshaping global medicine, approved for diabetes, obesity, and cardiovascular risk reduction, and under investigation for sleep apnoea and addiction....