Reshaping diabetes care: the fundamental role of dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists in clinical practice

The effect of antidiabetic medications on the cardiovascular system: a critical appraisal of current data

Both type 1 and type 2 diabetes are associated with increased risk for cardiovascular disease (CVD) events. This risk seems to be reduced by achievement of euglycemia. However, after the withdrawal of rosiglitazone from the market, the question arose as to whether this risk concerns simply a matter of euglycemia or the distinct role played by each antidiabetic drug with respect to its effect on CVD risk. To address this issue, many studies have been published during the last decade involving old and new antidiabetic agents, which however yielded contradictory results. Briefly, metformin is still considered safe and confers a beneficial effect on CVD risk. Conflicting data exist as concerns sulfonylureas, although the second and third generation representatives are regarded as relatively safe. Pioglitazone use seems to be associated with a reduction in CVD risk, whereas the dipeptidyl-dipeptidase-4 inhibitors (DPP-4i), lixisenatide and exenatide-LAR [from the category of glucagon-like-peptide-1 receptor (GLP-1R) agonists], confer a neutral effect. Two other GLP-1R agonists, liraglutide and semaglutide, as well as the sodium-glucose transporter-2 (SGLT2)-inhibitors, empagliflozin and cangliflozin, have shown an additional effect on CVD risk reduction, although their safety is in doubt. Insulin analogues and newer long-acting compounds are also safe for the cadiovascular system. The aim of this narrative review is to present and critically analyse the current data for each antidiabetic drug category with regard to their effect on CVD risk.

A crossover study of the combination therapy of metformin and exenatide or biphasic insulin aspart 30 in overweight or obese patients newly diagnosed with type 2 diabetes mellitus

The aim of the present study was to explore the effects of various combinations of exenatide, metformin (MET) and biphasic insulin aspart 30 (BIA30) on type 2 diabetes mellitus (T2DM). Two hundred overweight or obese patients newly diagnosed with T2DM were evenly randomized into two groups: A (twice daily for all: Phase I, 5 µg exenatide + 0.5 g MET for 4 weeks, then 10 µg exenatide + 0.5 g MET for 8 weeks; Phase II, 0.5 g MET for 12 weeks; Phase III, 0.3-0.4 U/kg/day BIA30 + 0.5 g MET for 12 weeks) and B (Phases I, II, III matched the phases III, II and I in group A). In groups A and B a significant decrease and increase, respectively, in glycated hemoglobin (HbAlc) and body mass index (BMI) was noted during Phase I. A 3.2±0.4-kg decrease in body weight in group A and a 2.6±0.3-kg increase in group B was observed. In Phase II, HbAlc was significantly increased in both groups (P<0.05). In Phase III, the BMI was increased in group A and reduced in group B (P<0.05). There was a 3.8±0.4-kg weight decrease in group B and 4.2±0.5-kg increase in group A (P<0.05). The combination of exenatide and MET promoted weight loss, glycemic control, β-cell function index, C peptide and adiponectin levels. These results suggested that the combination of exenatide and MET is better than the combination of BIA and MET for the therapy of overweight or obese patients newly diagnosed with T2DM.

Efficacy of sitagliptin for the hospital management of general medicine and surgery patients with type 2 diabetes (Sita-Hospital): a multicentre, prospective, open-label, non-inferiority randomised trial

BACKGROUND

The role of incretin-based drugs in the treatment of patients with type 2 diabetes admitted to hospital has not been extensively assessed. In this study, we compared the safety and efficacy of a dipeptidyl peptidase-4 inhibitor (sitagliptin) plus basal insulin with a basal-bolus insulin regimen for the management of patients with type 2 diabetes in general medicine and surgery in hospitals.

METHODS

We did a multicentre, prospective, open-label, non-inferiority randomised clinical trial (Sita-Hospital) in five hospitals in the USA, enrolling patients aged 18-80 years with type 2 diabetes and a random blood glucose concentration of 7·8-22·2 mmol/L who were being treated with diet or oral antidiabetic drugs or had a total daily insulin dose of 0·6 units per kg or less, admitted to general medicine and surgery services. We randomly assigned patients (1:1) to receive either sitagliptin plus basal glargine once daily (the sitagliptin-basal group) or a basal-bolus regimen with glargine once daily and rapid-acting insulin lispro or aspart before meals (the basal-bolus group) during the hospital stay. All other antidiabetic drugs were discontinued on admission. The randomisation was achieved by computer-generated tables with block stratification according to randomisation blood glucose concentrations (ie, higher or lower than 11·1 mmol/L). The primary endpoint of the trial was non-inferiority in mean differences between groups in their daily blood glucose concentrations during the first 10 days of therapy (point-of-care measurements; non-inferiority was deemed a difference <1 mmol/L). The safety endpoints included hypoglycaemia and uncontrolled hyperglycaemia leading to treatment failure. All participants who received at least one dose of study drug were included in the analysis. This study is registered with ClinicalTrials.gov, number NCT01845831.

FINDINGS

Between Aug 23, 2013, and July 27, 2015, we recruited 279 patients, and randomly assigned 277 to treatment; 138 to sitagliptin-basal and 139 to basal-bolus. The length of stay in hospital was similar for both groups (median 4 days [IQR 3-8] vs 4 [3-8] days, p=0·54). The mean daily blood glucose concentration in the sitagliptin-basal group (9·5 mmol/L [SD 2·7]) was not inferior to that in the basal-bolus group 9·4 mmol/L [2·7]) with a mean blood glucose difference of 0·1 mmol/L (95% CI -0·6 to 0·7). No deaths occurred in this trial. Treatment failure occurred in 22 patients (16%) in the sitagliptin-basal group versus 26 (19%) in the basal-bolus group (p=0·54). Hypoglycaemia occurred in 13 patients (9%) in the sitagliptin-basal group and in 17 (12%) in the basal-bolus group (p=0·45). No differences in hospital complications were noted between groups. Seven patients (5%) developed acute kidney injury in the sitagliptin-basal group and six (4%) in the basal-bolus group. One patient (0·7%) developed acute pancreatitis (in the basal-bolus group).

INTERPRETATION

The trial met the non-inferiority threshold for the primary endpoint, because there was no significant difference between groups in mean daily blood glucose concentrations. Treatment with sitagliptin plus basal insulin is as effective and safe as, and a convenient alternative to, the labour-intensive basal-bolus insulin regimen for the management of hyperglycaemia in patients with type 2 diabetes admitted to general medicine and surgery services in hospital in the non-intensive-care setting.

FUNDING

Merck.

Pharmacogenetics of type 2 diabetes mellitus: An example of success in clinical and translational medicine

The pharmacological interventions currently available to control type 2 diabetes mellitus (T2DM) show a wide interindividual variability in drug response, emphasizing the importance of a personalized, more effective medical treatment for each individual patient. In this context, a growing interest has emerged in recent years and has focused on pharmacogenetics, a discipline aimed at understanding the variability in patients’ drug response, making it possible to predict which drug is best for each patient and at what doses. Recent pharmacological and clinical evidences indicate that genetic polymorphisms (or genetic variations) of certain genes can adversely affect drug response and therapeutic efficacy of oral hypoglycemic agents in patients with T2DM, through pharmacokinetic- and/or pharmacodynamic-based mechanisms that may reduce the therapeutic effects or increase toxicity. For example, genetic variants in genes encoding enzymes of the cytochrome P-450 superfamily, or proteins of the ATP-sensitive potassium channel on the beta-cell of the pancreas, are responsible for the interindividual variability of drug response to sulfonylureas in patients with T2DM. Instead, genetic variants in the genes that encode for the organic cation transporters of metformin have been related to changes in both pharmacodynamic and pharmacokinetic responses to metformin in metformin-treated patients. Thus, based on the individual’s genotype, the possibility, in these subjects, of a personalized therapy constitutes the main goal of pharmacogenetics, directly leading to the development of the right medicine for the right patient. Undoubtedly, this represents an integral part of the translational medicine network.

Complementary Approaches to Improving Glucose Control-Insulin and Incretins: Patient Case Studies in Action

PURPOSE

The use of insulin and incretin-based therapies together has recently emerged as a new therapeutic option for patients with type 2 diabetes. This approach can be used across the continuum of diabetes and is supported by clinical trial evidence. To illustrate how these data may apply to clinical care, this supplement uses patient case studies to provide clinical context for diabetes educators. Relevant medical literature was searched and cited. Search terms included insulin, DPP-4 inhibitors, GLP-1 receptor agonists, hypoglycemia, and weight gain.

CONCLUSION

Insulin remains the most potent glucose-lowering agent available for the treatment of type 2 diabetes but has limitations, primarily of hypoglycemia and secondarily of weight gain. The addition of incretin-based therapies complements the glucose-lowering potential of basal insulin, without increasing the risk of hypoglycemia, potentially allowing for lower doses of insulin and without increasing weight gain (DPP-4 inhibitors) or possibly with weight loss (GLP-1 receptor agonists). Incretin-based therapies offer advantages over prandial insulin to address postprandial hyperglycemia.

Cardiovascular disease in diabetes mellitus: risk factors and medical therapy

Cardiovascular disease is a serious complication of diabetes mellitus. In the last 2 decades, great strides have been made in reducing microvascular complications in patients with diabetes through improving glycemic control. Decreasing rates of cardiovascular events have proved to be more difficult than simply intensifying the management of hyperglycemia. A tremendous effort has been made to deepen understanding of cardiovascular disease in diabetes and to formulate the best treatment approach. This review summarizes the current state of knowledge and discusses areas of uncertainty in the care of patients with diabetes who are at risk for cardiovascular disease.

Management of type 2 diabetes mellitus in older patients: current and emerging treatment options

Elderly patients with type 2 diabetes mellitus (T2DM) are a rapidly emerging population that presents unique clinical challenges. This diverse patient group can differ widely in terms of physical and mental status, which can increase their risk of complications including hypoglycemia, falls, and depression. These factors can negatively impact their glycemic control, safety, and quality of life. The risk of hypoglycemic events is elevated among elderly patients with diabetes. In many cases, these events are related to antidiabetic therapy and the pursuit of strict glycemic control. Fear of a hypoglycemic episode, on the part of the patient and/or healthcare provider, is another major barrier to achieving glycemic control. Hypoglycemic events, even in the absence of awareness of the event (asymptomatic), can have negative consequences. To help manage these risks, several national and international organizations have proposed guidelines to address individualized treatment goals for older adults with diabetes. This article reviews current treatment guidelines for setting glycemic targets in elderly patients with T2DM, and discusses the role of emerging treatment options in this patient population.