Gliptins - do they increase cardiovascular risk or benefit?

In 2008, the US FDA required all new glucose-lowering therapies to show cardiovascular safety, and this applies to the dipeptidyl peptidase-4 inhibitors ('gliptins').

The cardiovascular safety trials of saxagliptin and alogliptin have recently been published and are the subject of this evaluation.

The Saxagliptin Assessment of Vascular Outcomes Recorded in Patients with Diabetes Mellitus - Thrombolysis in Myocardial Infarction 53 trial and Examination of Cardiovascular Outcomes with Alogliptin versus Standard of Care were both multicentre, randomised, double-blind, placebo-controlled, Phase IV clinical trials. These trials showed that saxagliptin and alogliptin did not increase the primary end point, which was a composite of cardiovascular outcomes that did not include hospitalisations for heart failure. However, saxagliptin significantly increased hospitalisation for heart failure, which was a component of the secondary end point. The effect of alogliptin on hospitalisations for heart failure has not been reported. Neither agent improved cardiovascular outcomes. As there is no published evidence of improved outcomes with gliptins, it is unclear to us why these agents are so widely available for use. We suggest that the use of gliptins be restricted to Phase IV clinical trials until such time as cardiovascular safety and benefits/superiority are clearly established.