Amylin Pharmaceuticals, Inc and Eli Lilly and Company announced results from a randomized, double-blind, cross-over, four-week head-to-head study demonstrating that Byetta (exenatide) injection, a GLP-1 receptor agonist, provided significantly lower glucose levels in the post-meal setting when compared to Januvia (sitagliptin), a DPP-4 inhibitor.
Additionally, patients treated with Byetta reduced post-meal glucagon, showed more efficient use of their body's own insulin and decreased their food intake when compared to Januvia. This is the first reported head-to-head study directly comparing the therapeutic mechanisms of action (MOA) of Byetta and Januvia. The findings were presented at the 44th Annual Meeting of the European Association for the Study of Diabetes (EASD) in
Rome, Italy. The study will also be published in the peer-reviewed journal, Current Medical Research and Opinion.
"There has been some confusion in the marketplace about the therapeutic differences between Byetta and Januvia, and data from this first head-to-head study showed a clear difference in the MOAs and resultant short-term clinical effects between these two agents. Byetta works directly on the GLP-1 receptor, whereas Januvia indirectly affects GLP-1 levels," said Ralph DeFronzo, professor of medicine and chief of the Diabetes Division at the University of Texas Health Science Center in San Antonio and a clinical trial investigator on this study. "Patients on Byetta experienced significantly lower post-meal glucose levels, improved measures of beta cell function and decreased food intake."
The primary endpoint of this four-week study compared the effect of Byetta and Januvia on 2-hour post-meal glucose. Secondary endpoints included post-meal glucagon, insulin secretion rate, gastric emptying, and food intake. Patients were randomly assigned to treatment with either Byetta (5 mcg twice daily for the first week followed by 10 mcg twice daily for the second week) or Januvia (100 mg once daily) for two weeks; patients were then switched to the alternate therapy for the remaining two weeks. At baseline and at the end of each two week treatment period, patients underwent a standard meal test and other evaluations to assess each drug's effects on various measures of post-meal glucose control, indicators of beta cell function and other parameters.
Byetta is the first and only FDA-approved incretin mimetic for the treatment of type-2 diabetes.