Mixed Signals? No Data to Back Up Diabetes Drugs' Cancer Risks, Says EMA

Contrary to reports and pending lawsuits that claim otherwise, the FDA has publicly agreed with the findings of a study conducted by the European Medicines Agency (EMA) that conclude there is no existing evidence that indicates widely-used GLP-1 inhibitors are connected to the development of pancreatic cancer in type-2 diabetes patients. 

“The FDA concurs with the EMA’s conclusions regarding the potential pancreatic effects of GLP-1 based therapies,” an FDA spokeswoman told PharmaLive.com. “The agency believes that the current labeling for approved GLP-1 based therapies reflects the extent of our understanding of the safety signals at this point in time.”

Although the FDA is on board, the EMA made it clear, however, that despite their recent findings, no final conclusions—or changes in patients’ current treatment options—can or should be made until further studies can be undertaken.

“Due to their mechanism of action,” the EMA’s Committee for Medicinal Products for Human Use (CHMP) said in a statement, “some uncertainties remain in respect to the long-term effect of these medicines on the pancreas and more data collection efforts are under way.”

The EMA’s review, conducted by the CHMP, was done in response to a study published in Diabetes in March that found the GLP-1 inhibitors cause “marked” cell proliferation and damage in humans, as well as “display a potential for eventually transforming into cancer.” According to the CHMP, that study had “a number of methodological limitations and potential sources of bias” when it came to age, gender, disease duration and types of treatments among the test subjects.

After releasing its most recent findings, the EMA noted two large independent studies have been underway since 2011 to further investigate the risks associated with diabetes medications.  According to the EMA, the first conclusions of these studies are scheduled to be released in 2014.

At this point, these findings do not appear to be the final word on any pancreatic cancer risk associated with GLP-1 inhibitors. However, they have sparked additional investigative action into the risks associated with taking insulin production drugs. In early June, the FDA announced their own independent review into the safety of diabetes drugs. Furthermore, after the EMA’s latest findings were released, the American Diabetes Association (ADA) asked drug manufacturers to release patient-level data so that more accurate independent reviews can be conducted.

Despite the results of the EMA’s review, experts have raised red flags in confusion over why, if the results are accurate, the FDA has not changed the safety warning label on drugs such as Januvia. Although studies exist that seemingly prove Januvia users have an increased risk of developing pancreatic cancer and thyroid cancer, the FDA has said that “for now” there is “no evidence to show that Januvia is associated with higher cancer rates.”

Diabetes drugs such as Januvia and Byetta fall into a class of medications referred to as incretin mimetics, drugs that mimic the GLP-1 hormone responsible for stimulating insulin production.