A review of GLP-1 receptor agonists in type 2 diabetes: A focus on the mechanism of action of once-weekly agents

Efficacy and Safety of Subcutaneous and Oral Semaglutide Administration in Patients With Type 2 Diabetes: A Meta-Analysis

Background: This meta-analysis aimed to combine the data available from clinical trials to assess the effects of subcutaneous and oral semaglutide administration on glycemic control, weight management, and safety outcomes in patients with type 2 diabetes (T2D).

Methods: We systematically searched for phase 3 randomized controlled trials (RCTs) that compared semaglutide with placebo or other anti-diabetic drugs in T2D patients. The primary outcome was the change from baseline in glycated hemoglobin (HbA_1c) levels. Secondary efficacy endpoints included the change from baseline in body weight, achievement of HbA_1c targets, and clinically significant weight loss. Key safety outcomes were also assessed.

Results: In this meta-analysis, 24 trials with a total of 22185 patients were included. Subcutaneous semaglutide administration reduced HbA_1c levels (weighted mean difference [WMD]: −1.14% and −1.37%, for 0.5 mg and 1 mg, respectively) and body weight (WMD: −2.73 kg and −4.09 kg, for 0.5 mg and 1 mg, respectively) when compared with placebo; its efficacy was also superior to other anti-diabetic drugs in reducing HbA_1c levels (WMD: −0.71% and −0.86%, for 0.5 mg and 1 mg, respectively) and body weight (WMD: −2.65 kg and −3.78 kg, for 0.5 mg and 1 mg, respectively). Oral semaglutide administration was superior to placebo in decreasing HbA_1c levels (WMD: −0.96% and −1.02%, for 7 mg and 14 mg, respectively). Moreover, oral administration of 14 mg of semaglutide also showed a significant reduction in HbA_1c levels (WMD: −0.36%) compared with other anti-diabetic drugs. Furthermore, oral semaglutide administration resulted in substantial weight loss compared with other anti-diabetic drugs (WMD: −1.53 kg and −1.73 kg, for 7 mg and 14 mg, respectively). Notably, subcutaneous and oral semaglutide administration also resulted in higher numbers of patients achieving the targets of HbA_1c levels and weight loss than placebo and other anti-diabetic drugs. Overall, we noted no clear evidence of detrimental effects on safety endpoints due to semaglutide treatment, except for some gastrointestinal adverse events.

Conclusion: Both subcutaneous and oral semaglutide administration could enable the achievement of sufficient glycemic control and weight management without increasing the risk of hypoglycemia, which were effective and safe for the treatment of T2D.

A renaissance in the treatment of diabetic kidney disease, hypertension in chronic kidney disease, and beyond

Chronic kidney disease (CKD) affects approximately 15% of the US population and is associated with significant cardiovascular morbidity and mortality. The two leading causes of end stage kidney disease are hypertension and diabetes mellitus, both of which are modifiable risk factors. The cornerstones of CKD care include early detection, management of associated risk factors, modification of cardiovascular disease risk, slowing progression of disease, and management of complications including anemia, acid base disturbance, and mineral and bone disorders. For the last 20 years, renin-angiotensin system inhibitors were the mainstay treatment for proteinuric diabetic and nondiabetic kidney disease. Recently, new therapies such as sodium-glucose linked transporter 2 inhibitors, have emerged as powerful tools in the treatment of CKD with indications in both diabetic and nondiabetic kidney disease. In this article, we define CKD staging, review new hypertension and diabetic guidelines for CKD patients, and discuss major trials for new potential therapies in CKD, particularly diabetic kidney disease. We will provide practical guidance for primary care physicians to diagnose CKD and implement these agents early in the disease course to prevent the progression of disease and reduce the morbidity and mortality of this vulnerable population.

Optimal medical therapy after coronary artery bypass grafting: a primer for surgeons

PURPOSE OF REVIEW

After coronary artery bypass grafting (CABG), patients remain at increased risk of cardiovascular events and death. Cardiac surgeons have the opportunity to reduce this risk by optimizing post-CABG patients' medical therapy.

RECENT FINDINGS

Recent developments in lipid-lowering, diabetes management, antithrombotic therapy, and anti-inflammatory therapy can significantly improve prognosis in patients with chronic coronary artery disease. PCSK-9 inhibitors should be used in patients with elevated LDL cholesterol despite maximally tolerated statin therapy. Icosapent ethyl should be considered in patients with elevated triglycerides despite maximally tolerated statin therapy. Long-acting GLP-1 receptor agonists or SLGT-2 inhibitors should be used in all post-CABG patients with type 2 diabetes. Intensified antithrombotic therapy with DAPT or DPI reduces MACE (and DPI reduces mortality) in patients with high atherosclerotic burden. Colchicine has not yet been incorporated into guidelines on OMT for stable CAD but it is reasonable to consider using it in high-risk patients.

SUMMARY

We review the foundations of optimal medical therapy after CABG, and summarize recent advances with a focus on practical application for the busy cardiac surgeon.

Lipid effects of glucagon-like peptide 1 receptor analogs

PURPOSE OF REVIEW

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are becoming more prominent as a therapeutic choice in diabetes management and their use is being expanded to other indications, such as obesity. Dyslipidemia and cardiovascular disease are common co-morbidities in these populations and understanding the impact of this class of medications on the lipid profile may be an important consideration.

RECENT FINDINGS

Several GLP-1RAs trials demonstrate them to be safe and potentially beneficial for cardiovascular outcomes; improvements in surrogate markers of atherosclerosis have also been observed. Lipid data collected as secondary outcomes from large clinical trials as well as some smaller dedicated trials show that GLP-1RAs can modestly lower low-density lipoprotein (LDL) and total cholesterol (C), and most show modest fasting triglyceride (TG) lowering. Effects on high-density lipoprotein-C have been less consistent. Some have also demonstrated substantial blunting of the postprandial rise in serum TGs. Favorable effects on lipoprotein metabolism, with reduced levels of small dense LDL particles and decreased atherogenic potential of oxidized LDL, have also been seen. Mechanisms underlying these observations have been investigated.

SUMMARY

This review summarizes the data available on the lipid effects of GLP-1RAs, and explores the current understanding of the mechanisms underlying these observed effects.

Advances in venom peptide drug discovery: where are we at and where are we heading?

Introduction: Animal venoms are a complex mixture of bioactive molecules that have evolved over millions of years for prey capture and defense from predators. Venom consists of many different types of molecules, with disulfide-rich peptides being a major component in most venoms. The study of these potent and highly selective molecules has led to the development of venom-derived drugs for diseases such as type 2 diabetes mellitus and chronic pain. As technologies have improved, more bioactive peptides have been discovered from venomous animals. Many of these molecules may have applications as tools for understanding normal and disease physiology, therapeutics, cosmetics or in agriculture.Areas covered: This article reviews venom-derived drugs approved by the FDA and venom-derived peptides currently in development. It discusses the challenges faced by venom-derived peptide drugs during drug development and the future for venom-derived peptides.Expert opinion: New techniques such as toxin driven discovery are expanding the pipeline of venom-derived peptides. There are many venom-derived peptides currently in preclinical and clinical trials that would have remained undiscovered using traditional approaches. A renewed focus on venoms, with advances in technology, will broaden the diversity of venom-derived peptide therapeutics and expand our knowledge of their molecular targets.

Magnetic ligand fishing using immobilized DPP-IV for identification of antidiabetic ligands in lingonberry extract

In this work, a new magnetic ligand fishing probe for discovery of DPP-IV inhibitory ligands was developed and it was tested as a proof of concept on the fruit extract of Vaccinium vitis-idaea (lingonberry). The ligands were shown to have appreciable dipeptidyl peptidase IV (DPP-IV) inhibitory activity (IC₅₀: 31.8 μg mL-1).) Inhibition of DPP-IV is a well-known therapeutic approach for management of type 2 diabetes (T2D). DPP-IV was successfully immobilized onto magnetic beads and was shown to retain its catalytic activity and selectivity over a model mixture. A total of four ligands were successfully fished out and identified as cyanidin-3-galactoside (2), cyanidin-3-arabinoside (3), proanthocynidin A (4), and 10-carboxyl-pyranopeonidin 3-O-(6″-O-p-coumaroyl)-glucoside (5) using HPLC/HRMS.

Incretin Hormones and Type 2 Diabetes-Mechanistic Insights and Therapeutic Approaches

Simple Summary

When we ingest a meal, our intestine secretes hormones that are released into the bloodstream. Amongst these hormones are the incretins hormones which stimulate the release of insulin from the pancreas which is essential for the regulation of in particular postprandial glucose concentrations. In patients with type 2 diabetes, the effect of the incretins is diminished. This is thought to contribute importantly to the pathophysiology of the disease. However, in pharmacological amounts, the incretins may still influence insulin secretion and metabolism. Much research has therefore been devoted to the development of incretin-based therapies for type 2 diabetes. These therapies include compounds that strongly resemble the incretins, hereby stimulating their effects as well as inhibitors of the enzymatic degradation of the hormones, thereby increasing the concentration of incretins in the blood. Both therapeutic approaches have been implemented successfully, but research is still ongoing aimed at the development of further optimized therapies.

Abstract

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are secreted from the gut upon nutrient stimulation and regulate postprandial metabolism. These hormones are known as classical incretin hormones and are responsible for a major part of postprandial insulin release. The incretin effect is severely reduced in patients with type 2 diabetes, but it was discovered that administration of GLP-1 agonists was capable of normalizing glucose control in these patients. Over the last decades, much research has been focused on the development of incretin-based therapies for type 2 diabetes. These therapies include incretin receptor agonists and inhibitors of the incretin-degrading enzyme dipeptidyl peptidase-4. Especially the development of diverse GLP-1 receptor agonists has shown immense success, whereas studies of GIP monotherapy in patients with type 2 diabetes have consistently been disappointing. Interestingly, both GIP-GLP-1 co-agonists and GIP receptor antagonists administered in combination with GLP-1R agonists appear to be efficient with respect to both weight loss and control of diabetes, although the molecular mechanisms behind these effects remain unknown. This review describes our current knowledge of the two incretin hormones and the development of incretin-based therapies for treatment of type 2 diabetes.

Glycaemic and non-glycaemic efficacy of once-weekly GLP-1 receptor agonists in people with type 2 diabetes

WHAT IS KNOWN AND OBJECTIVE

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) may confer a range of benefits for people with type 2 diabetes (T2D), which is reflected through their position within diabetes treatment guidelines. The objective of this narrative review is to explore the efficacy data of once-weekly (QW) GLP-1 RAs in terms of glycaemic control, body weight reduction, cardiovascular (CV) outcomes and potential renal protective effects to assist pharmacists and other healthcare professionals (HCPs) in treatment discussions with patients.

METHODS

This a narrative review focused on 31 clinical trials involving the Phase 3 clinical programmes of the QW GLP-1 RAs dulaglutide, exenatide extended-release (ER) and semaglutide subcutaneous (s.c.).

RESULTS AND DISCUSSION

The clinical trials were divided by their comparator arms and examined for trends. All QW GLP-1 RAs were superior to placebo for reductions in glycated haemoglobin (HbA_1c ) and body weight. Data regarding QW GLP-1 RAs versus metformin were limited, likely due to metformin's use as the first-line pharmacologic for T2D. In the robust head-to-head trials of QW versus QW GLP-1 RAs, semaglutide s.c. was superior to both dulaglutide and exenatide ER regarding HbA_1c and body weight; however, QW versus once-daily GLP-1 RA trials had mixed results depending on the comparators. Finally, in QW GLP-1 RA versus insulin trials, all QW GLP-1 RAs were as effective as insulin, particularly when hypoglycaemia and body weight were also considered. CV outcome trials demonstrated benefits in major adverse CV events and renal outcomes for semaglutide and dulaglutide.

WHAT IS NEW AND CONCLUSION

This review collates recently published data and previously published Phase 3 results to allow pharmacists and other HCPs to understand all of the efficacy data available and the corresponding impact on treatment guidelines. QW GLP-1 RAs are emerging as important therapeutic options for people with T2D as they offer a spectrum of benefits extending beyond glycaemic control, but it is important to be aware of their efficacy differences when prescribing and discussing them with patients.

Managing the multifaceted nature of type 2 diabetes using once-weekly injectable GLP-1 receptor agonist therapy

WHAT IS KNOWN AND OBJECTIVE

As a highly prevalent chronic condition associated with complications and high mortality rates, it is important for pharmacists to have a comprehensive understanding of the impact of type 2 diabetes (T2D) and available treatment options. The use of injectable glucagon-like peptide 1 receptor agonists (GLP-1 RAs) is recommended as an effective and convenient treatment regimen for improving glycaemic control in individuals with T2D, with a good safety profile; however, the wider extent of its potential benefits often are unknown to clinical pharmacists. The objective of this article is to provide an overview of the impact of T2D on individuals and to discuss the multifaceted role of once-weekly (QW) GLP-1 RAs in addressing these challenges.

METHODS

This is a narrative review of the published literature regarding the use of injectable GLP-1 RAs in managing health complications in people with T2D.

RESULTS AND DISCUSSION

Recent findings reveal additional benefits of GLP-1 RAs in managing T2D complications, including atherosclerotic cardiovascular (CV) disease, retinopathy, neuropathy, and nephropathy. Dulaglutide and semaglutide have been shown to provide additional CV benefit in patients at high risk of CV events compared with standard of care/placebo and may offer renal protection in patients with chronic kidney disease. Cost-effectiveness studies, taking into consideration these different complications, have shown that QW GLP-1 RAs were cost-effective compared with other therapies. GLP-1 RAs may also help to improve overall health-related quality of life, reducing the risk of depression and 'diabetes distress', and limiting the risk of hypoglycaemia.

WHAT IS NEW AND CONCLUSION

From the literature, this appears to be the first review of the evidence supporting the multifaceted role of QW GLP-1 RAs in T2D, with particular emphasis on their use in comorbid conditions, as well as associated potential financial and well-being benefits. The results suggest that QW GLP-1 RAs may be an attractive treatment option for improving glycaemic control in T2D, especially in individuals with (or at risk of) additional comorbidities or health complications.

A review of GLP-1 receptor agonists in type 2 diabetes: A focus on the mechanism of action of once-weekly agents

WHAT IS KNOWN AND OBJECTIVE

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are one of the preferred approved treatment options for people with type 2 diabetes (T2D) and inadequate glycaemic control. The objective of this review is to provide a general clinical overview of the similarities and differences in the mechanisms of action (MoA) of the once-weekly GLP-1 RA class of medications, highlighting the role of pharmacists in providing optimal medication management, education and care for people with diabetes.

METHODS

This is a narrative review of the published literature regarding the MoA of the currently available once-weekly GLP-1 RAs in T2D.

RESULTS AND DISCUSSION

GLP-1 RAs have an established efficacy and safety profile. Their benefits derive from their blood glucose-lowering effects, which include pancreatic beta-cell-mediated glucose-dependent insulin secretion and suppressed glucagon release, and their ability to slow gastric emptying and promote satiety. GLP-1 RAs may also exert beneficial effects on multiple organ systems in which GLP-1 receptors are present, including the cardiovascular and renal systems. Differences between individual GLP-1 RAs with regard to their molecular size, structure and duration of action (short or longer acting) have led to differing pharmacodynamics and clinical effects such as degree of glycaemic control, weight loss abilities, cardiovascular effects and tolerability profiles.

WHAT IS NEW AND CONCLUSION

From the literature, this appears to be the first review of the evidence base supporting the MoA of once-weekly GLP-1 RAs in T2D aimed at pharmacists, with a particular emphasis on the expanding role of pharmacists in team-based diabetes management. As a class, GLP-1 RAs are an effective treatment option for people with T2D, shown to achieve multi-factorial clinical benefits. The results suggest that when selecting or advising about treatments, pharmacists should consider how the different once-weekly GLP-1 RAs and their MoA affect clinical outcomes in order to ensure optimal treatment for individuals.