Incretin-based therapies in 2021 - Current status and perspectives for the future

The role of atherogenic lipoproteins in diabetes: Molecular aspects and clinical significance

Dyslipidaemia plays a prominent role in the genesis of atherosclerotic plaque and the increased cardiovascular risk in diabetes. Macrophages readily take up atherogenic lipoproteins, transforming into foam cells and amplifying vascular damage in the presence of endothelial dysfunction. We discuss the importance of distinct lipoprotein subclasses in atherogenic diabetic dyslipidaemia as well as the effects of novel anti-diabetic agents on lipoprotein fractions and ultimately on cardiovascular risk prevention. In patients with diabetes, lipid abnormalities should be aggressively identified and treated in conjunction with therapeutical agents used to prevent cardiovascular disease. The use of drugs that improve diabetic dyslipidaemia plays a prominent role in conferring cardiovascular benefit in individuals with diabetes.

Effect of semaglutide versus other glucagon-like peptide-1 receptor agonists on cardio-metabolic risk factors in patients with type 2 diabetes: A systematic review and meta-analysis of head-to-head, phase 3, randomized controlled trials

INTRODUCTION

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have emerged as a cornerstone treatment for type 2 diabetes mellitus (T2DM). The aim of the present meta-analysis was to assess whether semaglutide exerts greater effects on glycemia and other cardio-metabolic risk factors compared to other GLP-1RAs.

METHODS

PubMed and Cochrane Library databases, along with grey literature sources, were searched form inception to 8th February 2023, in order to retrieve head-to-head, phase 3 randomized controlled trials (RCTs) assessing the effect of semaglutide versus other GLP-1RAs on glycemia and other cardio-metabolic risk factors in T2DM.

RESULTS

We finally pooled data from 5 RCTs in a total of 3760 randomized participants. Semaglutide compared to other GLP-1RAs provided a significantly greater reduction in HbA1c levels by 0.44 %, in fasting plasma glucose by 0.48 mmol/L, in body weight by 2.53 kg and in body mass index by 0.91 kg/m². Subjects receiving semaglutide experienced significantly greater odds for achieving target and optimal HbA1c, along with significantly greater odds for weight loss >5 % and 10 %. However, subjects randomized to semaglutide also experienced significantly greater odds for gastrointestinal adverse events and treatment discontinuation.

CONCLUSION

Semaglutide is more effective than rest GLP-1RAs, in terms of improvement in glycemia and other cardio-metabolic risk factors, among individuals with T2DM.

Effect of Semaglutide on Subclinical Atherosclerosis and Cardiometabolic Compensation: A Real-World Study in Patients with Type 2 Diabetes

BACKGROUND

Semaglutide is a recently approved glucagon-like peptide-1 receptor agonist. Several trials reported the protective effect of injectable semaglutide on cardiovascular (CV) risk by reducing major adverse cardiovascular events in type 2 diabetes patients. Strong preclinical evidence supports the CV benefits of semaglutide through an effect on atherosclerosis. However, scant evidence is available about the protective mechanisms of semaglutide in clinical practice.

METHODS

A retrospective observational study was conducted among consecutive type 2 diabetes patients treated with injectable semaglutide in Italy between November 2019 and January 2021 when the drug was first available in the country. The primary aims were the assessment of the carotid intima-media thickness (cIMT) and hemoglobin A1c (HbA1c) levels. The secondary aims were the evaluation of anthropometric, glycemic, and hepatic parameters and plasma lipids, including the assessment of the triglyceride/high-density lipoprotein ratio as an indirect marker of atherogenic small, dense low-density lipoprotein particles.

RESULTS

Injectable semaglutide reduced HbA1c and cIMT. An improvement in CV risk factors and the triglyceride/high-density lipoprotein ratio was reported. Moreover, through correlation analyses, we found that hepatic fibrosis and steatosis indices and the anthropometric, hepatic, and glycemic parameters, as well as plasma lipids, were unrelated to the variations in cIMT and HbA1c.

CONCLUSIONS

Our findings suggest the effect of injectable semaglutide on atherosclerosis as a key CV protective mechanism. Considering the favorable effects on atherogenic lipoproteins and hepatic steatosis indices, our results support the pleiotropic effect of semaglutide beyond glycemic control.

Circulating levels of gastrointestinal hormones in prediabetes reversing to normoglycemia or progressing to diabetes in a year-A cross-sectional and prospective analysis

AIMS

We aimed to compare the concentrations of GLP-1, glucagon and GIP (established regulators of glucose homeostasis) and glicentin (emerging new metabolic marker)during an OGTT in patients with normal glucose tolerance (NGT), prediabetes and diabetes at onset, and one-year before, when all had prediabetes.

METHODS

GLP-1, glucagon, GIP and glicentin concentrations were measured and compared with markers of body composition, insulin sensitivity and β-cell function at a 5-timepoint OGTT in 125 subjects (30 diabetes, 65 prediabetes, 30 NGT) and in 106 of them one-year before, when all had prediabetes.

RESULTS

At baseline, when all subjects were in prediabetic state, hormonal levels did not differ between groups. One year later, patients progressing to diabetes had lower postprandial increases of glicentin and GLP-1, lower postprandial decrease of glucagon, and higher levels of fasting GIP compared to patients regressing to NGT. Changes in glicentin and GLP-1 AUC within this year correlated negatively with changes in Glucose AUC of OGTT and with changes in markers of beta cell function.

CONCLUSION

Incretins, glucagon and glicentin profiles in prediabetic state cannot predict future glycemic traits, but prediabetes progressing to diabetes is accompanied by deterioration of postprandial increases of GLP-1 and glicentin.

Advances in the Pharmacological Management of Diabetic Nephropathy: A 2022 International Update

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD) worldwide. Its pathogenesis encompasses functional alterations involving elevated intraglomerular and systemic pressure, increased activity of the renin-angiotensin system (RAS) and oxidative stress, and the eventual development of renal fibrosis. The management of DN involves the optimization of blood pressure (BP) and blood glucose targets. However, treatment of these risk factors slows down but does not stop the progression of DN. Innovative pharmacologic therapies for dyslipidemia and type 2 diabetes mellitus (T2DM) could play a key role in bridging this gap and attenuating the residual risk of DN beyond traditional risk factor management. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs), sodium-glucose cotransporter-2 inhibitors (SGLT-2is), and inhibitors of mineralocorticoid receptor-mediated sodium reabsorption are recently introduced drug classes that have been shown to have positive effects on kidney function in individuals with T2DM. The aim of this review is to provide an update on the therapeutic options available in order to prevent or slow the onset and progression of DN in diabetic patients.

Pharmacotherapy of type 2 diabetes: An update and future directions

Type 2 diabetes (T2D) is a widely prevalent disease with substantial economic and social impact for which multiple conventional and novel pharmacotherapies are currently available; however, the landscape of T2D treatment is constantly changing as new therapies emerge and the understanding of currently available agents deepens. This review aims to provide an updated summary of the pharmacotherapeutic approach to T2D. Each class of agents is presented by mechanism of action, details of administration, side effect profile, cost, and use in certain populations including heart failure, non-alcoholic fatty liver disease, obesity, chronic kidney disease, and older individuals. We also review targets of novel therapeutic T2D agent development. Finally, we outline an up-to-date treatment approach that starts with identification of an individualized goal for glycemic control then selection, initiation, and further intensification of a personalized therapeutic plan for T2D.

Recent guidelines for Non-Alcoholic Fatty Liver disease (NAFLD)/ Fatty Liver Disease (FLD): Are they already outdated and in need of supplementation?

Non-Alcoholic Fatty Liver Disease (NAFLD) is a highly prevalent disease and unmet clinical need that we have recently proposed to be renamed for simplicity and accuracy as Fatty Liver Disease (FLD), with specific subclassifications. It has been commonly associated with metabolic comorbidities, including obesity, type 2 diabetes (T2D), hypertension, and hyperlipidemia. Since no Federal and Drug Administration (FDA) approved treatments exist to date, recent guidelines recommend lifestyle interventions, bariatric surgery, and pharmacotherapy, i.e. glucagon-like peptide-1 receptor agonists (GLP-1RA), peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists, and SGLT-2 inhibitors for its treatment. A new and novel medication for the treatment of T2D, tirzepatide, a dual GIP/GLP-1RA, was approved by the FDA only one week after guidelines were published, and ongoing clinical trials demonstrate promising results not only for T2D but also for body weight and steatosis. Moreover, we realize that distinct subgroups exist under the umbrella of FLD and, thus, more precise therapeutic recommendations would be needed towards the goal of personalized medicine and therapeutics for these subgroups. As the metabolism field is moving forward very fast and as several molecules in development will most likely demonstrate benefits in NAFLD treatment in the foreseeable future, guidelines will need to be frequently updated. This rapid pace of change prompts us to propose that guidelines should exist as living online documents on the websites of professional societies, so that they continue being updated following and reflecting the rapid progress in this and other fields of medicine.

An Update on the Current and Emerging Use of Thiazolidinediones for Type 2 Diabetes

Guidelines have increasingly stressed the concept that adequate glycemic control is required to prevent or decrease the macro- and microvascular complications of type 2 diabetes mellitus (T2DM). PPAR-gamma agonists (“glitazones”) are no longer prioritized due to their effects on heart failure. However, the association between these drugs and innovative therapies could be a valuable tool to attenuate the risk factors of the metabolic syndrome. Glitazones are used for the treatment of diabetes and associated comorbidities. There is substantial scientific evidence demonstrating the effect of glitazones at a cardiometabolic level, as well as on hematological and neurological pathologies that point to their usefulness. The use of glitazones has always been controversial both for the type of patients who must take these drugs and for the side effects associated with them. Unfortunately, the recent guidelines do not include them among the preferred drugs for the treatment of hyperglycemia and rosiglitazone is out of the market in many countries due to an adverse cardiovascular risk profile. Even though real-life studies have proven otherwise, and their pleiotropic effects have been highlighted, they have been unable to achieve primacy in the choice of antihyperglycemic drugs. It would be appropriate to demonstrate the usefulness of pioglitazone and its therapeutic benefit with further cardiovascular safety studies.

The Role of Physicians' Digital Tools in Pharmacological Management of Type 2 Diabetes Mellitus

Background and Objectives: The constantly increasing prevalence of type 2 diabetes mellitus (T2DM) and the advent of new treatment options have made management of T2DM patients more demanding. We aimed to (a) estimate the familiarity of general practitioners with novel T2DM treatment options, (b) determine whether a digital tool can aid in their treatment decisions and (c) demonstrate that an evidence-based digital clinical support tool can be made using an existing digital platform. Materials and methods: This proof-of-concept study consisted of two parts: We first conducted a simple online survey among general practitioners of three European countries to estimate their familiarity with novel T2DM treatment options and to determine whether they believe that a digital tool can aid in their T2DM treatment decisions. We then proceeded to develop a new digital tool that provides quick, evidence-based support for treatment of patients with T2DM using an existing digital platform. Results: The online survey was completed by 129/5278 physicians (94 from Italy, 22 from Czech Republic and 13 from Slovenia). Only 30.7% of all general practitioners reported to be either very or extremely familiar with novel T2DM treatments; the vast majority of participating general practitioners (82.8%) reported that they would find a digital clinical decision support tool for treating T2DM patients either very or extremely useful. A digital tool which features the characteristics deemed most important by the polled physicians was subsequently developed. Conclusions: The results of the online survey showed that familiarity of general practitioners with novel T2DM treatment options is relatively low and that there is a need for digital clinical decision support tools intended to facilitate treatment decisions in T2DM patients. We demonstrated that such a tool can easily be developed using an existing digital platform.

Translating results from the cardiovascular outcomes trials with glucagon-like peptide-1 receptor agonists into clinical practice: Recommendations from a Eastern and Southern Europe diabetes expert group

Glucagon-like peptide-1 (GLP-1) receptor agonists mimic the action of the endogenous GLP-1 incretin hormone, improving glycaemic control in type 2 diabetes mellitus (T2DM) by increasing insulin secretion and decreasing glucagon secretion in a glucose-dependent manner. However, as cardiovascular (CV) morbidity and mortality is common in patients with T2DM, several trials with the use of GLP-1 receptor agonists (RAs) have been performed focusing on endpoints related to cardiovascular disease rather than metabolic control of T2DM. Following the positive cardiovascular effects of liraglutide, dulaglutide and semaglutide observed in these trials, major changes in T2DM management guidelines have occurred. This document from a Eastern and Southern European Diabetes Expert Group discusses the results of GLP-1 RA CV outcomes trials, their impact on recent clinical guidelines for the management of T2DM, and some selected combination regimens utilising GLP-1 RAs. We also propose an algorithm for guiding GLP-1 RA-based treatment according to patients' characteristics, which can be easily applied in every day clinical practice.

Effect of Oral Semaglutide on Cardiovascular Parameters and Their Mechanisms in Patients with Type 2 Diabetes: Rationale and Design of the Semaglutide Anti-Atherosclerotic Mechanisms of Action Study (SAMAS)

INTRODUCTION

Type 2 diabetes (T2D) management has reached a point where not only optimal glycaemic control is necessary, but also additional interventions with proven cardiovascular risk reduction benefit. Subcutaneous semaglutide has been shown to provide cardiovascular protection, but its use may be limited by its injection formulation. To overcome this limitation, an oral semaglutide tablet has been developed, which could potentially be of the same value as its injection counterpart, but in a much wider group of patients with T2D, thereby allowing for broader cardiovascular risk reduction in this vulnerable patient population.

METHODS

A total of 100 consecutive patients with T2D and a disease duration of up to 10 years, without manifest cardiovascular disease, who are treated with metformin (± sulphonylurea) and optimal cardioprotective therapy, will be recruited in a single-blinded, randomized trial named "Semaglutide Anti-atherosclerotic Mechanisms of Action Study (SAMAS)." After 1:1 randomization, patients will receive either oral semaglutide 14 mg daily or placebo for 1 year. The primary outcome comprises changes in atherosclerosis-related structural and functional characteristics of the arterial wall, namely: reduction of the carotid intima-media thickness, improvement of endothelial function and decrease in arterial stiffness. Secondary outcomes are changes in atherogenic small dense low-density lipoproteins, glucose control (HbA1c) and inflammatory markers (hsCRP). Possible correlations between primary endpoints and changes in lipids, HbA1c and high-sensitivity C-reactive protein will be sought.

DISCUSSION

This is the first study to investigate the direct and indirect anti-atherosclerotic mechanisms of oral semaglutide. The results are expected to confirm the position of oral semaglutide in the multifactorial management of T2D with an emphasis on cardiovascular disease prevention.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05147896.

A New Look at Novel Cardiovascular Risk Biomarkers: The Role of Atherogenic Lipoproteins and Innovative Antidiabetic Therapies

The presence of residual cardiovascular disease (CVD) risk is a current dilemma in clinical practice; indeed, despite optimal management and treatment, a considerable proportion of patients still undergo major CV events. Novel lipoprotein biomarkers are suggested as possible targets for improving the outcomes of patients at higher risk for CVD, and their impact on major CV events and mortality have previously been investigated. Innovative antidiabetic therapies have recently shown a significant reduction in atherogenic lipoproteins, beyond their effects on glucose parameters; it has also been suggested that such anti-atherogenic effect may represent a valuable mechanistic explanation for the cardiovascular benefit of, at least, some of the novel antidiabetic agents, such as glucagon-like peptide-1 receptor agonists. This emphasizes the need for further research in the field in order to clearly assess the effects of innovative treatments on different novel biomarkers, including atherogenic lipoproteins, such as small dense low-density lipoprotein (LDL), lipoprotein(a) (Lp(a)) and dysfunctional high-density lipoprotein (HDL). The current article discusses the clinical importance of novel lipid biomarkers for better management of patients in order to overcome residual cardiovascular risk.

Glucagon-Like Peptide-1 Receptor Agonists and Dual Glucose-Dependent Insulinotropic Polypeptide/Glucagon-Like Peptide-1 Receptor Agonists in the Treatment of Obesity/Metabolic Syndrome, Prediabetes/Diabetes and Non-Alcoholic Fatty Liver Disease-Current Evidence

The obesity pandemic is accompanied by increased risk of developing metabolic syndrome (MetS) and related conditions: non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH), type 2 diabetes mellitus (T2DM) and cardiovascular (CV) disease (CVD). Lifestyle, as well as an imbalance of energy intake/expenditure, genetic predisposition, and epigenetics could lead to a dysmetabolic milieu, which is the cornerstone for the development of cardiometabolic complications. Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) and dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RAs promote positive effects on most components of the "cardiometabolic continuum" and consequently help reduce the need for polypharmacy. In this review, we highlight the main pathophysiological mechanisms and risk factors (RFs), that could be controlled by GLP-1 and dual GIP/GLP-1 RAs independently or through synergism or differences in their mode of action. We also address the evidence on the use of GLP-1 and dual GIP/GLP-1 RAs in the treatment of obesity, MetS and its related conditions (prediabetes, T2DM and NAFLD/NASH). In conclusion, GLP-1 RAs have already been established for the treatment of T2DM, obesity and cardioprotection in T2DM patients, while dual GIP/GLP-1 RAs appear to have the potential to possibly surpass them for the same indications. However, their use in the prevention of T2DM and the treatment of complex cardiometabolic metabolic diseases, such as NAFLD/NASH or other metabolic disorders, would benefit from more evidence and a thorough clinical patient-centered approach. There is a need to identify those patients in whom the metabolic component predominates, and whether the benefits outweigh any potential harm.

Diabetes and Colorectal Cancer Risk: A New Look at Molecular Mechanisms and Potential Role of Novel Antidiabetic Agents

Epidemiological data have demonstrated a significant association between the presence of type 2 diabetes mellitus (T2DM) and the development of colorectal cancer (CRC). Chronic hyperglycemia, insulin resistance, oxidative stress, and inflammation, the processes inherent to T2DM, also play active roles in the onset and progression of CRC. Recently, small dense low-density lipoprotein (LDL) particles, a typical characteristic of diabetic dyslipidemia, emerged as another possible underlying link between T2DM and CRC. Growing evidence suggests that antidiabetic medications may have beneficial effects in CRC prevention. According to findings from a limited number of preclinical and clinical studies, glucagon-like peptide-1 receptor agonists (GLP-1RAs) could be a promising strategy in reducing the incidence of CRC in patients with diabetes. However, available findings are inconclusive, and further studies are required. In this review, novel evidence on molecular mechanisms linking T2DM with CRC development, progression, and survival will be discussed. In addition, the potential role of GLP-1RAs therapies in CRC prevention will also be evaluated.