A new study suggests that patients using a class of Type 2 diabetes drugs called DPP-4 inhibitors are more likely to develop pancreatitis and pancreatic cancer compared to those prescribed alternative treatments.
These drugs lower blood sugar levels in Type 2 diabetics by blocking the action of DPP-4, an enzyme which destroys the hormone incretin. Incretins help the body produce more insulin only when it is needed and reduce the amount of glucose being produced by the liver when it is not needed. DPP-4 inhibitors belong to a larger class of diabetes drugs called incretin mimetics.
This new study, which was appears in Diabetes Care, drew data from the Korean National Health Insurance Service-Health Screening Cohort database to identify 33,208 adults with Type 2 diabetes who had at least on prescription for Januvia, Tradjenta, or Onglyza between 2007 and 2013. DPP-4s were not used by the remaining 22,990 individuals in the study population.
The authors were able to identify 1,084 instances of pancreatitis diagnosed within the cohort, including 215 instances of chronic pancreatitis and 869 instances of acute pancreatitis. The rate of pancreatitis among those taking DPP-4 inhibitors was 1,073 times per 100,000 person years, compared to 935 times per 100,000 person years for those using other medications. Patients taking DPP-4 inhibitors were 27% more likely to develop pancreatitis compared to non-users, and 24% more likely when a 6-month exposure lag period was taken into account.
DPP-4 users experienced pancreatic cancer 236 times per 100,000 person years, versus 200 times per 100,000 person-years for those taking other Type 2 diabetes drugs. Patients taking DPP-4 inhibitors were 50% more likely to develop the disease compared to non-users, and 81% more likely when the 6-month exposure lag period was incorporated.
“DPP-4i use is associated with increased risks of pancreatitis and pancreatic cancer in patients with newly diagnosed type 2 diabetes,” the study authors concluded. “However, the absence of increasing trend according to exposure duration suggests the chances of reverse causality, and long-term pancreatic safety of DPP-4i has to be further investigated.”
This study is not the first to suggest people taking DPP-4 inhibitors face an increased risk of pancreatitis and pancreatic cancer. In fact, Januvia and Onglyza are among several incretin mimetic diabetes drugs cited in dozens of pancreatic cancer lawsuits currently moving forward in the U.S. District Court, Southern District of California.
In 2013, studies published in JAMA Internal Medicine and Diabetes also linked incretin mimetics to increased risks for pancreatitis and pancreatic cancer. That same year, the U.S. Food & Drug Administration released a Drug Safety Communication warning of a possible association between incretin mimetic diabetes drugs and pancreatitis, as well as pre-cancerous changes to the pancreatic tissue.
An additional study published in 2016 contradicted the earlier findings, but doctors were cautioned to continue incretin mimetic patients for signs of the disease.