AIM:Alogliptin, an efficacious inhibitor of DPP-4 that improves glycemic control, as well as the pancreatic beta-cell function, is now increasingly used to accomplish glycemic targets in type 2 diabetic patients. Interestingly, recent experimental studies have shown that alogliptin exerts anti-atherosclerotic effects in GLP-1-dependent and -independent manners. The aim of the present ongoing study is to investigate the preventive effects of alogliptin on the progression of atherosclerosis in type 2 diabetic subjects using the carotid intima-media thickness (IMT), an established marker of cardiovascular disease. METHODS AND RESULTS:The Study of Preventive Effects of Alogliptin on Diabetic Atherosclerosis (SPEAD-A) is a prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group, comparative study. Between March 2011 and March 2012, 341 participants were recruited at 11 clinical sites, and were randomly allocated either to an alogliptin treatment group (172 patients) or a conventional treatment group (169 patients). The primary outcomes are the changes in the maximum and mean IMT of the common carotid artery during a 24-month treatment period, as measured by carotid arterial echography. The secondary outcomes include the changes in glycemic control, parameters related to beta-cell function and diabetic nephropathy, the occurrence of cardiovascular events and adverse events and biochemical measurements reflecting vascular function. CONCLUSIONS:This is the first study to address the effects of DPP-4 inhibitors on the progression of changes in the carotid IMT, with the patients without DPP-4 inhibitor treatment serving as a control group. The results will be available soon, and these findings are expected to provide clinical data that will be helpful in the prevention of diabetic atherosclerosis and subsequent cardiovascular disease.