Safety of Diabetes Drugs

Two studies published in professional journals this year have cast renewed doubt about the safety of one of our most important class of diabetes drugs. But the leading regulatory agencies both in Europe and the U.S. seem to think that those studies are flawed.

We call this class of drugs incretin-based or GLP-1 agonists. They include Byetta, Victoza, and Bydureon.

The most recent investigation of this class of drugs came out last month in the American Diabetes Association’s journal Diabetes Care. Dr. Peter Butler of UCLA is the lead author of “A Critical Analysis of the Clinical Use of Incretin-Based Therapies.” It was prompted by a study conducted by Dr. Sonal Singh and colleagues at the Johns Hopkins University School of Medicine, “Glucagonlike Peptide 1–Based Therapies and Risk of Hospitalization for Acute Pancreatitis in Type 2 Diabetes Mellitus.” That article appeared in JAMA, and both are available online.

The concern is that these diabetes drugs may lead to a higher incidence of pancreatitis and pancreatic cancer. This is, however, old news that I have been writing for years. “A Byetta Pancreatitis Perspective” appeared here in October 2007 and “Neither Byetta or Januvia Increase the Risk of Acute Pancreatitis.” One of these studies indicates that patients taking Byetta or Januvia  were no more likely to develop acute pancreatitis than patients taking other drugs to control diabetes.  The study indicates there is an increased risk of acute pancreatitis for people with diabetes. But that it is not associated with the particular diabetic medication the patients are using. The other report looked at the 30 cases of pancreatitis reported to the U.S. Food and Drug Administration, but 27 of those cases had other risk factors, like alcoholism, which has long been well known to be associated with pancreatitis.

The latest twist in this convoluted story is that the European Medicines Agency’s Committee for Medicinal Products for Human Use says that the evidence doesn’t show a link between these drugs and those diseases. After finalizing its review, it “concluded that presently available data do not confirm recent concerns over an increased risk of pancreatic adverse events with these medicines.”

Earlier, the FDA reported that it “has not reached any new conclusions about safety risks with incretin mimetic drugs.” Subsequently, I have read tantalizing reports from a trade publication called BioCentury that the FDA concurs with the European Medicines Agency that the medications and disease are not linked.

Should we be concerned about using these potent diabetes drugs now? I think that it would be prudent to have a little concern, but not only with these drugs but with any drug.

All drugs that work for good — as these drugs certainly do in helping us control both our blood sugar and our weight — have the potential for working for bad. Some drugs are, of course, worse than others.

Rezulin killed many people with diabetes before the FDA withdrew it in 2000. We have serious concerns right now with two other drugs in the same class, Avandia and Actos. Even metformin, probably the safest oral medication for diabetes, may cause lactic acidosis in a small number of people.

We have to get as much knowledge as we can about the medications that we put in our bodies, then balance the benefits and risks, and finally weigh the odds. Our doctors and nurses can help, but we are responsible for our own bodies, and we must make the final call.

This article is based on an earlier version of my article published by HealthCentral.