Government-sponsored researchers from the U.S. and Europe indicate that they see no link in the currently available data between a risk of pancreatic cancer and the diabetes drugs Byetta, Januvia, Janumet, and Victoza. However, they acknowledge that a connection may exist that has not yet been proven.
In a report published by the New England Journal of Medicine on February 27, officials from the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) assessed the risk of pancreatitis and pancreatic cancer associated with a class of diabetes drugs known as incretin mimetics.
The assessment indicates that there is no evidence establishing a causal link to pancreatic cancer with Byetta, Januvia other other similar medications. The findings are contrary to a number of recent studies that have suggested an increased risk of acute pancreatitis, pancretic cancer and thyroid cancer among users of the drugs. However, the agencies indicate that they looked at the same data, and gathered even more, but were unable to come to the same conclusions.
The agencies say they looked at data from animal tests, post-marketing studies, pre-marketing clinical trials and adverse event reports before reaching their conclusions.
“Both agencies agree that assertions concerning a causal association between incretin-based drugs and pancreatitis or pancreatic cancer, as expressed recently in the scientific literature and in the media, are inconsistent with the current data,” the assessment concludes. “The FDA and the EMA have not reached a final conclusion at this time regarding such a causal relationship. Although the totality of the data that have been reviewed provides reassurance, pancreatitis will continue to be considered a risk associated with these drugs until more data are available; both agencies continue to investigate this safety signal.”
A number of other studies have suggest a strong association between the drugs and pancreatitis or pancreatic cancer, though none demonstrate a cause and effect relationship, which is traditionally hard to find in such cases.
The most recent study was published in October by Italian researchers, who looked at 1,169 adverse drug reaction reports. They identified at least 90 cases of users of incretin mimetics suffering from pancreatitis and elevated pancreatic enzymes. Acute or chronic pancreatitis can lead to the development of pancreatic cancer in some cases.
In February 2013, researchers from Johns Hopkins in Baltimore found that taking Januvia or Byetta may double the risk of hospitalization due to pancreatitis, which raised concerns about whether this may also suggest an increased risk of pancreatic cancer.
In March 2013, the risk of pancreatic cancer from Januvia, Byetta and other incretin mimetics gained additional attention after another study published in the medical journal Diabetes found that pancreas tissue from organ donors found that those who took an incretin mimetic were more likely to have increased pancreatic mass and precancerous cells, which are cells with the potential to evolve into tumors.
Byetta (exenatide) was the first member of the incretin mimetic class of diabetes drugs, which was introduced by Amylin Pharmaceuticals in 2005 as a twice daily injection. Bydureon (exenatide extended-release) was introduced by Amylin in January 2012, as a once-weekly injection. Amylin was then acquired by Bristol-Myers Squibb in July 2012, for $5.3 billion.
Diabetes Drug Litigation
There are currently more than 300 Byetta lawsuits, Januvia lawsuits, Janumet lawsuits and Victoza lawsuits filed throughout the federal court system, which all involve allegations that former users were diagnosed with pancreatic cancer after using the diabetes drugs. The complaints claim that the drug makers failed to adequately research the medications or warn about the potential side effects.
As the number of complaints began to spike throughout the federal court system, the U.S. Judicial Panel on Multidistrict Litigation (JPML) established coordinated proceedings in the federal court system in August 2013.
All pancreatic cancer cases involving the use Januvia, Janumet, Byetta or Victoza are currently consolidated as part of an MDL, or Multidistrict Litigation, which is centralized before U.S. District Judge Anthony J. Battalglia in the Southern District of California to reduce duplicative discover, avoid conflicting pretrial rulings from different judges and to serve the convenience of the parties, witnesses and the courts.
At this time, the MDL is limited to just cases against the makers of Byetta, Januvia, Janumet and Victoza for plaintiffs who allege they developed pancreatic cancer. However, the scope of the litigation is expanding. A growing number of Byetta thyroid cancer lawsuits have also been filed, which may eventually be centralized as part of an MDL as well. In addition, several Onglyza lawsuits have been filed on behalf of former users of this other incretin mimetic diabetes drug who have been diagnosed with pancreatic cancer.