A common drug used to lower blood sugar in type 2 diabetics has been observed to increase risk of pancreatitis, and is believed to also increase long-term pancreatic cancer risk.
Sitagliptin, which is sold in pill form under the market name Januvia, increases glucagon-like peptide 1 (GLP-1) activity, which in turn helps lower blood glucose levels. According to the current study, however, this benefit comes with a significant risk of damaging the pancreas. The following observations solidify warnings made by the Food and Drug Administration (FDA), connecting the drug Byetta, which is similar in action to Januvia, to pancreatitis.
Pancreatitis describes inflammation of the pancreas, and often results in severe abdominal pain. While pancreatitis is a potentially dangerous and fatal condition, it is often treatable. The even more troubling observation of the current study is that long-term use of Januvia may lead to pancreatic cancer, a disease with much higher mortality rates and painful treatment procedures than pancreatitis.
Tests were performed on an animal model, mice mimicking symptoms of type 2 diabetic humans. Sitagliptin was administered solely in some mice, and in combination with a different common type 2 diabetes drug, metformin (marketed under the name Glucophage), in others. The study was conducted over a 12 week period. Metformin is known to have anti-tumor properties, and it was indeed observed that pancreatic cells were protected in mice given both sitagliptin and metformin.
For mice being administered only sitagliptin, the results were very unfavorable. Pancreatitis was developed in one of the 40 mice in the 12 week period, but almost all mice taking sitagliptin had significantly increased pancreatic cell production, a sign of risk for both pancreatitis and future pancreatic cancer. This observation was made, necessarily, by removing the pancreas of each mouse. Notes lead researcher Dr. Peter Butler, “A concern here is that the unwanted effects of this drug on the pancreas would likely not be detected in humans unless the pancreas was removed and examined.”
While the results of this study do not provide specific reason for why sitagliptin increases pancreatitis and pancreatic cancer risk, a conclusion which will require further and innovative research on the subject, it certainly suggests that Januvia should not be taken alone, or specifically without also taking glucophage. Concludes Dr. Butler, “the apparent protection against the unwanted actions of sitagliptin in the exocrine pancreas are intriguing and may offer a potential way of using the GLP-1 class of drugs safely. The protective effect may have been either by the actions of metformin to decrease blood glucose values or its recently appreciated properties as a tumor suppressive agent. Given these findings, it is probably sensible to use the GLP-1 class of drugs only with metformin until other data is forthcoming.”
Source: Defeat Diabetes Foundation: Butler, Peter. Rivero, Enrique. UCLA news release. April 2009.