A new report shows a possible link between two newer type 2 diabetes drugs and pancreatitis and cancer of the pancreas. One of the drugs might also cause thyroid cancer. Researchers found patients taking the drugs sitagliptin (Januvia) and exenatide (Byetta) had a significantly higher chance of developing the diseases.
The finding, published in the journal Gastroenterology, links the two diabetes drugs to an increase in the chances of pancreatitis and cancer of the pancreas. Researchers also found an increased risk that patients taking one of the drugs might develop thyroid cancer, compared to those whose diabetes is treated with other therapies.
The results come from a search of the FDA’s adverse event database. The scientists looked at reports from 2004 to 2009.
Dr. Peter Butler, director of the Larry L. Hillblom Islet Research Center at UCLA and a study co-author said the researchers decided to look at the link between pancreatitis and cancer and the diabetes drugs because animal studies showed the medications can promote growth of the pancreatic ducts – tubes that carry digestive juices to the gut.
Butler said, “This is a concern if it happens in humans since it might be expected to increase the risk for pancreatitis and pancreatic cancer. While the FDA data base has limitations, it does have advantages in being very large, openly accessible and independent from companies that market the drugs.”
Butler, who is also a member of UCLA’s Jonsson Comprehensive Cancer Center says more studies need to be done to ensure the drugs that are now widely available for type 2 diabetes treatment aren’t putting patients at high risk for pancreatic cancer.
The 2 drugs investigated lower blood sugar levels for diabetics by promoting the action of a hormone in the gut known as glucagon-like peptide 1 (GLP-1).
The diabetes medication Januvia was found to up the risk of pancreatic cancer 6 fold, while Byetta might almost triple the risk. Byetta was also associated with thyroid cancer risk.
The FDA warns that the data extracted from the adverse event reports may not be reliable because of lack of information and reporting bias.
The study authors warn that randomized, controlled clinical trials, which are considered the “gold standard” for research, are needed to assess whether the type 2 diabetes drugs raise the risk of pancreatitis or cancer of the pancreas or thyroid.
"Pancreatitis, Pancreatic, and Thyroid Cancer With Glucagon-Like Peptide-1–Based Therapies"
Michael Elashoff, et al.
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