Byetta, Januvia Cancer Risks DebatedSep 21, 2011 | Parker Waichman LLP
The uncertainty surrounding type 2 diabetes drugs like Byetta and Januvia have prompted calls for more studies of glucagon-like peptide 1 (GLP-1) therapies. A recent study has tied Byetta and Januvia to a possible increased risk of pancreatic cancer, but other researchers, along with the drug's manufacturers.
GLP-1 therapies mimic a hormone called GLP-1 to stimulate natural insulin production in diabetics. In addition to Byetta and Januvia, Novo Nordisk's Victoza is also in this class. In January 2010, a U.S. Food & Drug Administration (FDA) official wrote a memo suggesting Byetta and other GLP-1diabetes drugs might have safety risks. According to a report from EmaxHealth, the FDA delayed approving Byetta, but never required more studies.
The debate over the drug's safety risks took center state last week at the European Association for the Study of Diabetes (EASD) conference in Lisbon last week.
"The data we have so far makes the question sufficiently robust that it has to be answered," Peter Butler, a researcher at the University of California at Los Angeles, said in an interview with Bloomberg News. "Hopefully this debate will raise the awareness of the scientific community, so that people will be motivated to join in the research."
Butler was co-author of a study published in the journal Gastroenterology that found Januvia and Byetta were associated with a higher risk of pancreatic cancer, as well as pancreatitis and thyroid cancer. The Gastroenterology study was based on an analysis of reports made to the U.S. Food & Drug Administration (FDA) Adverse Event Reporting Database between 2004 and 2009.
In Lisbon last week, Novo Nordisk asserted that the FDA's voluntary reporting system can't be used to calculate the incidence of side effects.
A German researcher, Michael Nauck, head of the Diabeteszentrum Bad Lauterberg in Harz, Germany, also countered Butler. "The bulk of findings tends to speak against such an association," he told Bloomberg. "There is no general agreement."
According to Bloomberg, both Nauck and Butler did agree that randomized clinical trials are needed to conclusively show whether GLP-1 therapies carry an increased risk of cancer.
Others at the meeting acknowledged that the uncertainty was impacting the way they prescribe GLP-1 therapies.
"I don't think there is evidence at all that GLP-1 analogues may induce cancer at this stage," Carl Johan Oestgren, a professor at the Department of Medical and Health Sciences at Linkoeping University in Sweden. Still, "When new drugs come to the market, it's very important to be careful at the beginning." According to Bloomberg, Oestgren also said he only prescribes GLP-1 analogues "for a few patients."