Sitagliptin improves beta-cell function in patients with acute coronary syndromes and newly diagnosed glucose abnormalities--the BEGAMI study

Sitagliptin reduces FAP-activity and increases intact FGF21 levels in patients with newly detected glucose abnormalities

INTRODUCTION

Fibroblast growth factor 21 (FGF21), a hormone with pleiotropic metabolic effects, is inactivated by fibroblast activation protein (FAP), a member of the dipeptidyl peptidase-IV (DPP-IV) family. We investigate if sitagliptin (DPP-IV inhibitor) inhibits FAP-activity and increases intact FGF21.

METHODS

Patients with impaired glucose metabolism were randomized to 100 mg sitagliptin (n = 34) or placebo (n = 37) treatment for 12 weeks. Plasma samples obtained at study entry and at 12-weeks were analysed for FAP-activity, FAP, total FGF21 and intact FGF21.

RESULTS

Sitagliptin significantly inhibited FAP-activity (497 ± 553 vs. 48 ± 712 RFU/min, p < 0.01) and correspondingly increased intact FGF21 (253 ± 182 vs 141 ± 80 ng/L, p < 0.01) compared to placebo in plasma. Sitagliptin dose-dependently inhibited the FAP-activity in vitro. Intact FGF21 was higher in patients obtaining a normal glucose tolerance regardless of treatment (p = 0.03).

CONCLUSION

A sitagliptin-induced increase of intact FGF21 may contribute to an improved metabolic effect in patients with impaired glucose metabolism.

The Impact of Hypoglycemic Therapy on the Prognosis for Acute Coronary Syndrome in Patients with Type 2 Diabetes

The article discusses particular circumstances of acute coronary syndrome (ACS) in patients with type 2 diabetes (T2D). In addition, the available literature data and clinical guidelines reflecting the role of hypoglycemic therapy as a cardioprotection factor in ACS are analyzed. The article considers possible protective molecular mechanisms of various groups of drugs in ischemic cardiomyocytes.

Acute and long-term effects of saxagliptin on post-prandial glycemic response in obese patients with impaired glucose tolerance

BACKGROUND AND AIMS

Dipeptidyl-peptidase inhibitors might be useful in type 2 diabetes prevention. ACCES (ACute and Chronic Effects of Saxagliptin) was a randomized, placebo-controlled, double-blind, controlled phase 2, pilot study aiming to examine in obese patients with impaired glucose tolerance (IGT) the acute effects and the effects after 12 weeks of treatment by saxagliptin on glucose levels at fasting and postprandially after a standard breakfast, and on glucose tolerance.

METHODS AND RESULTS

We included 24 obese patients with IGT. Patients were randomized to receive saxagliptin 5 mg or placebo in the morning. The treatment was taken on Visit 1 before breakfast, then continued for 12 weeks. Biochemical measurements were performed before, one, two and three hours after a standard breakfast including 75 g of carbohydrates, during Visit 1 and Visit 2 (12 weeks). Glucose variability (GV) was evaluated at Visit 1 from 24-h continuous glucose monitoring including the breakfast. A second OGTT was performed at Visit 3 (3-5 days after Visit 2). Compared with placebo-treated patients, saxagliptin-treated patients had lower 1 h and 2 h post-meal plasma glucose levels at Visit 1 and similar changes at Visit 2 (p < 0.01 to p < 0.004), with lower GV indexes after breakfast at Visit 1. At Visit 3, all patients but one in saxagliptin group and only 4 patients in placebo group turned to normal glucose tolerance. Lower glucose response to breakfast at Visit 1 was predictive of recovery of glucose tolerance.

CONCLUSION

Saxagliptin has metabolically beneficial effects in glucose-intolerant obese patients by significantly lowering postprandial blood glucose levels.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01521312: https://clinicaltrials.gov/ct2/show/NCT01521312.

Effect of dipeptidyl peptidase-4 inhibitors on complement activation

BACKGROUND

Adverse activation of the complement cascade in the innate immune system appears to be involved in development of vascular complications in diabetes. Dipeptidyl peptidase-4 (DPP-4) is a cell surface serine protease expressed in a variety of tissues. DPP-4 inhibitors are widely used in treatment of type 2 diabetes and appear to yield beneficial pleiotropic effects beyond their glucose-lowering action, for example, renoprotective and anti-inflammatory properties, but the exact mechanisms remain unknown. We hypothesised that DPP-4 inhibitors block adverse complement activation by inhibiting complement-activating serine proteases.

MATERIALS AND METHODS

We analysed the effects of 7 different DPP-4 inhibitors on the lectin and classical pathway of the complement system in vitro by quantifying complement factor C4b deposition onto mannan or IgG coated surfaces, respectively. Furthermore, plasma concentrations of mannan-binding lectin (MBL), soluble membrane attack complex (sMAC), and C4b deposition were quantified in 71 patients with a recent acute coronary syndrome and glucose disturbances, randomly assigned to sitagliptin 100 mg (n = 34) or placebo (n = 37) for 12 weeks.

RESULTS

All the 7 DPP-4 inhibitors tested in the study directly inhibited functional activity of the lectin pathway in a dose-dependent manner with varying potency in vitro. In vivo, MBL, sMAC, and C4b declined significantly during follow-up in both groups without significant effect of sitagliptin.

CONCLUSIONS

We demonstrated an inhibitory effect of DPP-4 inhibitors on the lectin pathway in vitro. The clinical relevance of this effect of DPP-4 inhibitors remains to be fully elucidated.

Stress-Induced Hyperglycaemia in Non-Diabetic Patients with Acute Coronary Syndrome: From Molecular Mechanisms to New Therapeutic Perspectives

Stress-induced hyperglycaemia (SIH) at hospital admission for acute coronary syndrome is associated with poor outcome, especially in patients without known diabetes. Nevertheless, insulin treatment in these subjects was not correlated with the reduction of mortality. This is likely due to the fact that SIH in the context of an acute coronary syndrome, compared to that in known diabetes, represents an epiphenomenon of other pathological conditions, such as adrenergic and renin-angiotensin system over-activity, hyperglucagonaemia, increase of circulating free fatty acids and pancreatic beta-cell dysfunction, which are not completely reversed by insulin therapy and so worsen the prognosis. Thus, SIH may be considered not only as a biomarker of organ damage, but also as an indicator of a more complex therapeutic strategy in these subjects. The aim of this review is to analyse the molecular mechanisms by which SIH may favour a worse prognosis in non-diabetic patients with acute coronary syndrome and identify new therapeutic strategies, in addition to insulin therapy, for a more appropriate treatment and improved outcomes.

Current and emerging pharmacotherapy for prediabetes: are we moving forward?

INTRODUCTION

Prediabetes is a state wherein blood glucose levels are above normal but below the diagnostic threshold for diabetes. Seventy percent of patients with prediabetes develop type 2 diabetes in their lifetime. Despite this, prediabetes frequently goes undiagnosed.

AREAS COVERED

This review focuses on the pharmacological treatment of prediabetes and the prevention of progression to diabetes. A literature search was carried out on PubMed and Embase to review randomized controlled trials examining treatment of prediabetes. Emerging pharmacological therapies with potential benefit are discussed.

EXPERT OPINION

Lifestyle intervention is the cornerstone for preventing progression to diabetes, but metformin remains the first line pharmacological intervention. There appears to be minimal additive effect of combining metformin with lifestyle changes. It would be interesting to assess whether using combination pharmacological approaches plus or minus lifestyle interventions have any additive benefit. Despite the good level of evidence available, the penetrance of any interventions remains very low in part due to the prodromal categorization of the prediabetic state.

Dipeptidyl-peptidase (DPP)-4 inhibitors and glucagon-like peptide (GLP)-1 analogues for prevention or delay of type 2 diabetes mellitus and its associated complications in people at increased risk for the development of type 2 diabetes mellitus

BACKGROUND

The projected rise in the incidence of type 2 diabetes mellitus (T2DM) could develop into a substantial health problem worldwide. Whether dipeptidyl-peptidase (DPP)-4 inhibitors or glucagon-like peptide (GLP)-1 analogues are able to prevent or delay T2DM and its associated complications in people at risk for the development of T2DM is unknown.

OBJECTIVES

To assess the effects of DPP-4 inhibitors and GLP-1 analogues on the prevention or delay of T2DM and its associated complications in people with impaired glucose tolerance, impaired fasting blood glucose, moderately elevated glycosylated haemoglobin A1c (HbA1c) or any combination of these.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials; MEDLINE; PubMed; Embase; ClinicalTrials.gov; the World Health Organization (WHO) International Clinical Trials Registry Platform; and the reference lists of systematic reviews, articles and health technology assessment reports. We asked investigators of the included trials for information about additional trials. The date of the last search of all databases was January 2017.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with a duration of 12 weeks or more comparing DPP-4 inhibitors and GLP-1 analogues with any pharmacological glucose-lowering intervention, behaviour-changing intervention, placebo or no intervention in people with impaired fasting glucose, impaired glucose tolerance, moderately elevated HbA1c or combinations of these.

DATA COLLECTION AND ANALYSIS

Two review authors read all abstracts and full-text articles and records, assessed quality and extracted outcome data independently. One review author extracted data which were checked by a second review author. We resolved discrepancies by consensus or the involvement of a third review author. For meta-analyses, we planned to use a random-effects model with investigation of risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the overall quality of the evidence using the GRADE instrument.

MAIN RESULTS

We included seven completed RCTs; about 98 participants were randomised to a DPP-4 inhibitor as monotherapy and 1620 participants were randomised to a GLP-1 analogue as monotherapy. Two trials investigated a DPP-4 inhibitor and five trials investigated a GLP-1 analogue. A total of 924 participants with data on allocation to control groups were randomised to a comparator group; 889 participants were randomised to placebo and 33 participants to metformin monotherapy. One RCT of liraglutide contributed 85% of all participants. The duration of the intervention varied from 12 weeks to 160 weeks. We judged none of the included trials at low risk of bias for all 'Risk of bias' domains and did not perform meta-analyses because there were not enough trials.One trial comparing the DPP-4 inhibitor vildagliptin with placebo reported no deaths (very low-quality evidence). The incidence of T2DM by means of WHO diagnostic criteria in this trial was 3/90 participants randomised to vildagliptin versus 1/89 participants randomised to placebo (very low-quality evidence). Also, 1/90 participants on vildagliptin versus 2/89 participants on placebo experienced a serious adverse event (very low-quality evidence). One out of 90 participants experienced congestive heart failure in the vildagliptin group versus none in the placebo group (very low-quality evidence). There were no data on non-fatal myocardial infarction, stroke, health-related quality of life or socioeconomic effects reported.All-cause and cardiovascular mortality following treatment with GLP-1 analogues were rarely reported; one trial of exenatide reported that no participant died. Another trial of liraglutide 3.0 mg showed that 2/1501 in the liraglutide group versus 2/747 in the placebo group died after 160 weeks of treatment (very low-quality evidence).The incidence of T2DM following treatment with liraglutide 3.0 mg compared to placebo after 160 weeks was 26/1472 (1.8%) participants randomised to liraglutide versus 46/738 (6.2%) participants randomised to placebo (very low-quality evidence). The trial established the risk for (diagnosis of) T2DM as HbA1c 5.7% to 6.4% (6.5% or greater), fasting plasma glucose 5.6 mmol/L or greater to 6.9 mmol/L or less (7.0 mmol/L or greater) or two-hour post-load plasma glucose 7.8 mmol/L or greater to 11.0 mmol/L (11.1 mmol/L). Altogether, 70/1472 (66%) participants regressed from intermediate hyperglycaemia to normoglycaemia compared with 268/738 (36%) participants in the placebo group. The incidence of T2DM after the 12-week off-treatment extension period (i.e. after 172 weeks) showed that five additional participants were diagnosed T2DM in the liraglutide group, compared with one participant in the placebo group. After 12-week treatment cessation, 740/1472 (50%) participants in the liraglutide group compared with 263/738 (36%) participants in the placebo group had normoglycaemia.One trial used exenatide and 2/17 participants randomised to exenatide versus 1/16 participants randomised to placebo developed T2DM (very low-quality evidence). This trial did not provide a definition of T2DM. One trial reported serious adverse events in 230/1524 (15.1%) participants in the liraglutide 3.0 mg arm versus 96/755 (12.7%) participants in the placebo arm (very low quality evidence). There were no serious adverse events in the trial using exenatide. Non-fatal myocardial infarction was reported in 1/1524 participants in the liraglutide arm and in 0/55 participants in the placebo arm at 172 weeks (very low-quality evidence). One trial reported congestive heart failure in 1/1524 participants in the liraglutide arm and in 1/755 participants in the placebo arm (very low-quality evidence). Participants receiving liraglutide compared with placebo had a small mean improvement in the physical component of the 36-item Short Form scale showing a difference of 0.87 points (95% CI 0.17 to 1.58; P = 0.02; 1 trial; 1791 participants; very low-quality evidence). No trial evaluating GLP-1-analogues reported data on stroke, microvascular complications or socioeconomic effects.

AUTHORS' CONCLUSIONS

There is no firm evidence that DPP-4 inhibitors or GLP-1 analogues compared mainly with placebo substantially influence the risk of T2DM and especially its associated complications in people at increased risk for the development of T2DM. Most trials did not investigate patient-important outcomes.

Cardiovascular Safety of Dipeptidyl-Peptidase IV Inhibitors: A Meta-Analysis of Placebo-Controlled Randomized Trials

BACKGROUND

Large randomized trials have shown conflicting evidence regarding the cardiovascular safety of dipeptidyl-peptidase 4 (DPP-4) inhibitors. Systematic reviews have been limited by incomplete data and inclusion of observational studies. This study aimed to systematically evaluate the cardiovascular safety of DPP-4 inhibitors in patients with type 2 diabetes.

METHODS

Electronic databases were searched for randomized trials that compared DPP-4 inhibitors versus placebo and reported cardiovascular outcomes. The main outcome assessed in this analysis was heart failure. Other outcomes included all-cause mortality, cardiovascular mortality, myocardial infarction, and ischemic stroke. Summary odds ratios (ORs) were primarily constructed using Peto's model.

RESULTS

A total of 90 trials with 66,730 patients were included. Compared with placebo, DPP-4 inhibitors were associated with a non-significant increased risk of heart failure [OR 1.11, 95% confidence interval (CI) 0.99-1.25, P = 0.07] at a mean of 108 weeks. The risk of all-cause mortality (OR 1.03, 95% CI 0.94-1.12, P = 0.53), cardiovascular mortality (OR 1.02, 95% CI 0.92-1.14, P = 0.72), myocardial infarction (OR 0.98, 95% CI 0.88-1.09, P = 0.69), and ischemic stroke (OR 0.99, 95% CI 0.85-1.15, P = 0.92) was similar between both groups.

CONCLUSION

In patients with type 2 diabetes, the safety profile of DPP-4 inhibitors is similar to placebo. As a class, there is only weak evidence for an increased risk of heart failure.

Copeptin, insulin-like growth factor binding protein-1 and sitagliptin: A report from the BEta-cell function in Glucose abnormalities and Acute Myocardial Infarction study

PURPOSE

To investigate whether sitagliptin affects copeptin and osmolality, suggesting arginine vasopressin activation and a potential for fluid retention, compared with placebo, in patients with a recent acute coronary syndrome and newly discovered type 2 diabetes or impaired glucose tolerance. A second aim was to confirm whether copeptin correlated with insulin-like growth factor binding protein-1.

METHODS

Fasting blood samples were used from the BEta-cell function in Glucose abnormalities and Acute Myocardial Infarction trial, in which patients recently hospitalized due to acute coronary syndrome and with newly detected abnormal glucose tolerance were randomized to sitagliptin 100 mg once daily (n = 34) or placebo (n = 37). Copeptin, osmolality and insulin-like growth factor binding protein-1 were analysed at baseline and after 12 weeks.

RESULTS

Copeptin and osmolality were unaffected by sitagliptin. There was no correlation between copeptin and insulin-like growth factor binding protein-1.

CONCLUSION

Sitagliptin therapy does not appear to be related to activation of the arginine vasopressin system.

Improved glycemic control due to sitagliptin is not related to cortisol or the surrogate marker IGFBP-1 for hepatic insulin sensitivity

IMPORTANCE

Elevated cortisol levels and dysregulated insulin-like growth factor binding protein-1 (IGFBP-1; a marker of hepatic insulin sensitivity) are both related to insulin resistance and glucose abnormalities. It is unknown whether improvement in these parameters is related to improved glucose metabolism during treatment with sitagliptin.

OBJECTIVE

To determine whether improved insulin sensitivity and beta-cell function during treatment with sitagliptin is related to lower cortisol levels and/or improved regulation of IGFBP-1 in patients with recent acute coronary syndrome (ACS) and newly discovered glucose abnormalities.

DESIGN

Samples were taken from The BEta-cell function in Glucose abnormalities and Acute Myocardial Infarction (BEGAMI) trial, a double-blinded, placebo-controlled randomized clinical trial on the efficacy and safety of sitagliptin for patients with ACS and newly discovered glucose abnormalities.

SETTING

Cardiology departments (cardiac ICU and outpatient clinic) in two hospitals in Stockholm, Sweden.

PARTICIPANTS

Subjects hospitalized (or recently hospitalized) for ACS, in whom an oral glucose tolerance test revealed previously unknown glucose abnormalities.

INTERVENTIONS

Subjects were randomized to sitagliptin 100mg once daily (n=34) or placebo (n=37) for twelve weeks. Oral glucose tolerance test (OGTT) and randomization occurred after stabilization median 7 days after ACS.

MAIN OUTCOMES AND MEASURES

Fasting serum cortisol and IGFBP-1 were analyzed before OGTT, around 8a.m., and after at 10a.m. The latter time point was chosen as the spread in cortisol levels around is small then, allowing improved chances to detect differences between groups.

RESULTS

Glucose tolerance and insulin sensitivity improved in both groups, while HbA1c and indices of β-cell function improved only in the sitagliptin group as reported previously. Both groups displayed decreased cortisol levels around 10a.m. (from 338±21 to 278±14 nmol/L, p=0.038, in the sitagliptin group; from 343±17 to 302±15 nmol/L, p=0.017, in the placebo group), and improved correlation between fasting log-IGFBP-1 and insulin.

CONCLUSIONS AND RELEVANCE

These findings suggest that a stress-related elevation in cortisol may have negative impact on glucose tolerance in patients with recent ACS. However, improved glycemic control with sitagliptin does not appear to be related to changes in cortisol levels or hepatic insulin sensitivity as assessed by IGFBP-1.

Sitagliptin improves glycaemic excursion after a meal or after an oral glucose load in Japanese subjects with impaired glucose tolerance

AIMS

To evaluate the efficacy and tolerability of sitagliptin in subjects with impaired glucose tolerance (IGT).

METHODS

In a double-blind, parallel-group study, 242 Japanese subjects with IGT, determined by a 75-g oral glucose tolerance test (OGTT) at week -1, were randomized (1 : 1 : 1) to placebo (n = 83), sitagliptin 25 mg (n = 82) or 50 mg (n = 77) once daily for 8 weeks. Glycaemic variables were assessed using another OGTT at week 7 and meal tolerance tests (MTTs) at weeks 0 and 8. Primary and secondary endpoints were percent change from baseline in glucose total area under the curve 0-2 h (AUC(0 -2 h)) during the MTT and OGTT, respectively.

RESULTS

Least squares mean percent change from baseline in glucose AUC(0 -2 h) during the MTT were -2.4, -9.5 and -11.5%, and during the OGTT were -3.7, -21.4 and -20.1% with placebo, sitagliptin 25 mg once daily, and 50 mg once daily, respectively (p < 0.001 for either sitagliptin dose vs placebo in both tests). Sitagliptin treatment enhanced early insulin response during the OGTT and decreased total insulin response, assessed as the total AUC(0 -2 h) during the MTT. Sitagliptin treatment also suppressed glucagon response during the MTT. The incidence of adverse events, including hypoglycaemia, was low and generally similar in all treatment groups.

CONCLUSIONS

Treatment with sitagliptin significantly reduced glucose excursions during both an MTT and an OGTT; this effect was associated with an increase in early insulin secretion after oral glucose loading as well as a blunted glucagon response during an MTT. Sitagliptin was generally well tolerated in subjects with IGT.

Pharmacological interventions for preventing or delaying onset of type 2 diabetes mellitus

Prevention or delay of onset of type 2 diabetes in individuals at varying risk across the dysglycaemia continuum before overt diabetes becomes clinically manifest constitutes a leading objective of global disease prevention schemes. Pharmacological intervention has been suggested as a means to help prevent diabetes and reduce the global burden of this chronic condition. However, there is no credible evidence that early pharmacological intervention leads to long-term benefit in reducing diabetes-related complications or preventing early mortality, compared to treating people with diagnosed diabetes who have crossed the glycaemic threshold. In this review, we examine published evidence from trials using pharmacological agents to delay or prevent progression to diabetes. We also explore the benefit/risk impact of such therapies, safety issues and relevant off-target effects. Current evidence suggests none of the drugs currently available sustainably lower cumulative diabetes incidence, none provides a durable delay in diabetes diagnosis and none provides a convincing concomitant excess benefit for microvascular or macrovascular risk.

Incretin-based therapies in prediabetes: Current evidence and future perspectives

The prevalence of type 2 diabetes (T2D) is evolving globally at an alarming rate. Prediabetes is an intermediate state of glucose metabolism that exists between normal glucose tolerance (NGT) and the clinical entity of T2D. Relentless β-cell decline and failure is responsible for the progression from NGT to prediabetes and eventually T2D. The huge burden resulting from the complications of T2D created the need of therapeutic strategies in an effort to prevent or delay its development. The beneficial effects of incretin-based therapies, dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists, on β-cell function in patients with T2D, together with their strictly glucose-depended mechanism of action, suggested their possible use in individuals with prediabetes when greater β-cell mass and function are preserved and the possibility of β-cell salvage is higher. The present paper summarizes the main molecular intracellular mechanisms through which GLP-1 exerts its activity on β-cells. It also explores the current evidence of incretin based therapies when administered in a prediabetic state, both in animal models and in humans. Finally it discusses the safety of incretin-based therapies as well as their possible role in order to delay or prevent T2D.

The DPP-4 inhibitor sitagliptin and endothelial function in patients with acute coronary syndromes and newly detected glucose perturbations: A report from the BEGAMI study

OBJECTIVE

Compromised endothelial function contributes to poor prognosis in patients with coronary artery disease and type 2 diabetes. Incretin-based therapy may exert beneficial cardiovascular effects beyond glucose lowering. We tested whether sitagliptin improves endothelial function.

RESEARCH DESIGN AND METHODS

In the double-blind BEta-cell function in patients with Glucose Abnormalities and Acute Myocardial Infarction (BEGAMI) trial, acute coronary syndrome (ACS)-patients with newly detected impaired glucose tolerance (IGT) or type 2 diabetes mellitus (T2DM) were randomised to sitagliptin 100 mg (n = 31) or placebo (n = 33) during 12 weeks. Endothelial function was studied as reactive hyperaemia index (RHI).

RESULTS

At baseline, the RHI was slightly compromised in both groups (sitagliptin 1.67; Q1;Q3: 1.46;2.17 vs placebo 1.61; 1.44;1.96; ns). The RHI did not change during the study period and was 1.57 (1.40;2.36) in the sitagliptin and 1.60 (1.46;1.81; ns) in the placebo group after treatment.

CONCLUSION

Sitagliptin did not improve endothelial function in patients with ACS and newly detected glucose perturbations.

Cardiovascular effects of dipeptidyl peptidase-4 inhibitors: from risk factors to clinical outcomes

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) are oral incretin-based glucose-lowering agents with proven efficacy and safety in the management of type 2 diabetes mellitus (T2DM). In addition, preclinical data and mechanistic studies suggest a possible additional non-glycemic beneficial action on blood vessels and the heart, via both glucagon-like peptide-1-dependent and glucagon-like peptide-1-independent effects. As a matter of fact, DPP-4 inhibitors improve several cardiovascular risk factors: they improve glucose control (mainly by reducing the risk of postprandial hyperglycemia) and are weight neutral; may lower blood pressure somewhat; improve postprandial (and even fasting) lipemia; reduce inflammatory markers; diminish oxidative stress; improve endothelial function; and reduce platelet aggregation in patients with T2DM. In addition, positive effects on the myocardium have been described in patients with ischemic heart disease. Results of post hoc analyses of phase 2/3 controlled trials suggest a possible cardioprotective effect with a trend (sometimes significant) toward lower incidence of major cardiovascular events with sitagliptin, vildagliptin, saxagliptin, linagliptin, or alogliptin compared with placebo or other active glucose-lowering agents. However, the definite relationship between DPP-4 inhibition and better cardiovascular outcomes remains to be proven. Major prospective clinical trials involving various DPP-4 inhibitors with predefined cardiovascular outcomes are under way in patients with T2DM and a high-risk cardiovascular profile: the Sitagliptin Cardiovascular Outcome Study (TECOS) on sitagliptin, the Saxagliptin Assessment of Vascular Outcomes Recorded in Patients With Diabetes Mellitus-Thrombolysis in Myocardial Infarction (SAVOR-TIMI) 53 trial on saxagliptin, the Cardiovascular Outcomes Study of Alogliptin in Subjects With Type 2 Diabetes and Acute Coronary Syndrome (EXAMINE) trial on alogliptin, and the Cardiovascular Outcome Study of Linagliptin Versus Glimepiride in Patients With Type 2 Diabetes (CAROLINA) on linagliptin. If these trials confirm that a DPP-4 inhibitor can reduce the cardiovascular burden of T2DM, it would be major progress that would dramatically influence the management of the disease.