September 4, 2013
Continued Use of Incretins Recommended, Despite
Cancer Questions

Jacksonville, FL—No definitive link has been proven between use of the incretin class of diabetes medications and an increased risk for developing cancer, according to the American Association of Clinical Endocrinologists (AACE), which recommends the continued use of the drugs with some caution.

“Clinicians can continue to confidently prescribe all FDA-approved antihyperglycemic medications for the management of hyperglycemia according to established practice guidelines,” according to a new diabetes and cancer consensus statement paper, which adds that “in patients who have an elevated cancer risk or positive family history of cancer, the cautious selection of anti-hyperglycemic medications is both prudent and warranted.”

The report also is available in the online issue of the journal Endocrine Practice.

The statement was in line with a recent report from the European Medicines Agency’s Committee for Medicinal Products for Human Use on GLP-1-based diabetes therapies. The FDA has also found the evidence insufficient to mandate a label change on the drugs, but, as recently as March, issued a drug safety communication about a possible link between incretin mimetics and pancreatitis as well as precancerous changes in the pancreas. The FDA conceded that its findings were based on examination of “a small number of pancreatic tissue specimens taken from patients after they died from unspecified causes.”

Drugs in the incretin mimetic class include exenatide (Byetta, Bydureon), liraglutide (Victoza), sitagliptin (Januvia, Janumet, Janumet XR, Juvisync), saxagliptin (Onglyza, Kombiglyze XR), alogliptin (Nesina, Kazano, Oseni), and linagliptin (Tradjenta, Jentadueto), according to the FDA.

The consensus statement from the Jacksonville, FL-based AACE also pointed out that the incretin mimetic drugs have not been approved and used long enough to really determine if they are linked to cancer development: Clinical appearance of a pancreatic neoplasm following an initiating event can take 12 years, with another decade usually required before appearance of metastatic disease.

“Because it has been less than 8 years since the introduction of the first drug in the incretin class (exenatide in 2005), there would not have been enough time for a definitive exposure-cancer development relationship to be established,” according to the task force.

Despite the “lack of data from large-scale randomized study designs,” task force members conceded that with observational data suggesting an increased cancer risk in people with diabetes, “an association cannot be ruled out.”

The consensus report also noted that obesity is linked to a number of cancers, adding, “It would appear that the most compelling scenario for cancer development may include a combination of prolonged obesity due to excess caloric intake plus the resulting increase of circulating insulin, [insulin-like growth factors], cytokines, and inflammatory molecules.”

U.S. Pharmacist Social Connect