FDA Backtracks Over GLP-1s’ Effects on Pancreas

The U.S. Food and Drug Administration reports that its review of various animal and human studies does not show a link between GLP-1 drugs used to treat type 2 diabetes and pancreatic maladies, including acute pancreatitis and pancreatic cancer.

GLP-1 drugs, which work by stimulating the body to produce insulin, include Bristol-Myers Squibb’s Byetta and Bydureon, Merck’s Januvia and Janumet, and Novo Nordisk’s Victoza.

However, the agency says that it has not reached a final conclusion about the drugs’ safety and will continue to study them for adverse effects. In the meantime, GLP-1 drugs’ labels will continue to carry the FDA-mandated warnings about possible effects on the pancreas.

What’s interesting about the FDA decision is that it’s indicative of an agency that approached a perceived problem using bad science and is now backtracking.

When concerns about Byetta, the first GLP-1 drug to hit the U.S. market, began surfacing in 2008, the agency focused on one statistic: Out of a conservatively estimated 700,000 users of Byetta, 36 had developed acute pancreatitis, from which four had died. This, said the FDA, was cause to look into issuing a black box warning for the drug.

A black box warning alerts users that the FDA considers a drug to pose a significant risk of adverse effects. In a way it’s like Internet sites that warn visitors about disturbing content and offer them a yes/no option for entering–“Proceed at your own risk.”)

At the time, Diabetes Health pointed out the near absurdity of sounding an alarm over the possibility that one out of approx. every 19,000 users of Byetta had developed pancreatitis as the result of taking the drug, and one out of every 175,000 had died from it.

In its backtrack, the FDA cited insurance statistics as the cause of its initial concern. At the time that the agency began scrutinizing Byetta, which had become one of the most popular and successful type 2 drugs in history, other pharma industry observers were already disputing the GLP-1-pancreatitis connection (see first link below).

(One critic of our 2008 article pointing out the ludicrousness of the FDA statistics said that it was possible that many Byetta-related cases of pancreatitis had gone unreported or not been connected to the drug. But, since we couldn’t work with imaginary numbers, we decided it was fair to comment on the FDA’s own statistics–the statistics upon which it was basing a crucial labeling decision.)

Aside from the appallingly small statistical sample that the FDA based its alarm on, one critic noted that people with type 2 diabetes already run an increased risk of pancreatic problems regardless of the drugs they take.

Adding to the problems for Byetta that the agency’s ill-advised warnings created was the media’s unquestioning characterization of the drug as posing risks, with even the prestigious Wall Street Journal labeling the drug “controversial,” while providing no supporting evidence for the FDA’s assertion.

Links to previous Diabetes Health articles on this topic:



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