Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo and active-controlled, parallel-group, phase 2 trial conducted in the USA

Multifunctional incretin peptides in therapies for type 2 diabetes, obesity and associated co-morbidities

Recent studies with peptide-based incretin therapies have focussed mainly on the glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide and the dual agonist tirzepatide that engages receptors for GLP-1 and glucose-dependent insulinotropic polypeptide (GIP). Randomised clinical trials and 'real-world' studies have confirmed the marked glucose-lowering and weight-lowering efficacy of these agents across diverse populations. These include different ethnic groups, young and elderly individuals with and without diabetes and/or overweight or obesity. Recent studies have also confirmed protections against the development and progression of cardiovascular and renal diseases that are additive to the benefits conferred by improved control of blood glucose and body weight. Emerging evidence suggests that incretin therapies could additionally ameliorate fatty liver disease, chronic inflammation, sleep apnea and possibly degenerative bone disorders and cognitive decline. New incretin-based peptide therapies in development include a long-acting glucagon receptor agonist (LY3324954), dual GLP-1/glucagon receptor agonists (survodutide, pemvidutide, mazdutide, G49), triple GLP-1/GIP/glucagon receptor agonists (retatrutide, efocipegtrutide), a combination of semaglutide with the amylin analogue cagrilintide (CagriSema), a unimolecular GLP-1/amylin receptor dual agonist (amycretin), and a GIP receptor antibody with GLP-1 receptor agonism (MariTide). The creation of multi-targeting incretin-based synthetic peptides provides opportunities for improved management of type 2 diabetes and obesity as well as new therapeutic approaches to an expanding list of associated co-morbidities. The aim of the review is to acquaint the reader with developments in the field from 2023 to the present (February 2025).

Glucose-dependent insulinotropic polypeptide (GIP)

BACKGROUND

Glucose-dependent insulinotropic polypeptide (GIP) was the first incretin identified and plays an essential role in the maintenance of glucose tolerance in healthy humans. Until recently GIP had not been developed as a therapeutic and thus has been overshadowed by the other incretin, glucagon-like peptide 1 (GLP-1), which is the basis for several successful drugs to treat diabetes and obesity. However, there has been a rekindling of interest in GIP biology in recent years, in great part due to pharmacology demonstrating that both GIPR agonism and antagonism may be beneficial in treating obesity and diabetes. This apparent paradox has reinvigorated the field, led to new lines of investigation, and deeper understanding of GIP.

SCOPE OF REVIEW

In this review, we provide a detailed overview on the multifaceted nature of GIP biology and discuss the therapeutic implications of GIPR signal modification on various diseases.

MAJOR CONCLUSIONS

Following its classification as an incretin hormone, GIP has emerged as a pleiotropic hormone with a variety of metabolic effects outside the endocrine pancreas. The numerous beneficial effects of GIPR signal modification render the peptide an interesting candidate for the development of pharmacotherapies to treat obesity, diabetes, drug-induced nausea and both bone and neurodegenerative disorders.

Beta-cell preservation in T2DM using a pathophysiologic approach

Type 2 diabetes and obesity rates continue to rise. Type 2 diabetes affects 1-2 million new individuals annually. Despite a wide range of treatment options for type 2 diabetes, many people still fail to achieve therapeutic goals. Treating type 2 diabetes more proactively with a pathophysiologic approach can ensure higher rates of success and reduce complications. This article summarizes the progressive understanding of the pathophysiology of diabetes, draws a connection between illness and beta-cell health, and introduces the pathophysiologic approach to type 2 diabetes and its focus on beta-cell preservation. This article compiled clinical data, evidence-based medicine, and experimental results to create a comprehensive narrative review.

Dual and Triple Gut Peptide Agonists on the Horizon for the Treatment of Type 2 Diabetes and Obesity. An Overview of Preclinical and Clinical Data

PURPOSE OF REVIEW

The development of long-acting incretin receptor agonists represents a significant advance in the fight against the concurrent epidemics of type 2 diabetes mellitus (T2DM) and obesity. The aim of the present review is to examine the cellular processes underlying the actions of these new, highly significant classes of peptide receptor agonists. We further explore the potential actions of multi-agonist drugs as well as the mechanisms through which gut-brain communication can be used to achieve long-term weight loss without negative side effects.

RECENT FINDINGS

Several unimolecular dual-receptor agonists have shown promising clinical efficacy studies when used alone or in conjunction with approved glucose-lowering medications. We also describe the development of incretin-based pharmacotherapy, starting with exendin- 4 and ending with the identification of multi-incretin hormone receptor agonists, which appear to be the next major step in the fight against T2DM and obesity. We discuss the multi-agonists currently in clinical trials and how each new generation of these drugs improves their effectiveness. Since most glucose-dependent insulinotropic polypeptide (GIP) receptor: glucagon-like peptide- 1 receptor (GLP- 1) receptor: glucagon receptor triagonists compete in efficacy with bariatric surgery, the success of these agents in preclinical models and clinical trials suggests a bright future for multi-agonists in the treatment of metabolic diseases. To fully understand how these treatments affect body weight, further research is needed.

Structural pharmacology and mechanisms of GLP-1R signaling

Glucagon-like peptide-1 receptor (GLP-1R), a class B1 G protein-coupled receptor, plays critical roles in glucose homeostasis. Recent structural pharmacology studies using cryogenic electron microscopy, X-ray crystallography, mass spectrometry, and functional analyses, have provided valuable insights into its activation by endogenous hormones and mono- or dual agonists like semaglutide and tirzepatide, highly effective in treating type 2 diabetes and obesity. They highlight significant conformational changes in the extracellular and transmembrane domains of GLP-1R that drive receptor activation and downstream signal transduction. Additionally, allosteric modulators, supported by emerging structural information, show great promises as an alternative strategy. Future research investigating unexplored effector interactions, biased signaling, weight rebound mechanisms, and personalized therapy strategies will be critical for developing better therapeutic agents targeting GLP-1R.

Efficacy of 12 months therapy with glucagon-like peptide-1 receptor agonists liraglutide and semaglutide on weight regain after bariatric surgery: a real-world retrospective observational study

BACKGROUND

The role of glucagon-like peptide-1 receptor agonists (GLP1-RAs) in patients with weight regain after bariatric surgery remains unclear. The objective of this study was to determine the efficacy and safety of 12 months of GLP1-RA treatment in a real-world patient population with weight regain after bariatric surgery.

METHODS

A single-centre retrospective observational study. Patients with post-bariatric weight regain subsequently treated with GLP1-RA were identified, and the effect on weight after 12 months of treatment was determined. Data are presented as medians (interquartile ranges) or frequencies (%), and Wilcoxon signed-rank tests and Mann-Whitney U tests were used for paired and nonpaired group comparisons, respectively.

RESULTS

Forty patients (80% female) were included in the analysis. Liraglutide (3.0 mg, daily subcutaneous injection, n = 22) or semaglutide (1.0 mg, weekly subcutaneous injection, n = 18) was started 74.5 (51.0, 108.3) months after surgery following a weight regain of 14.7 (10.3, 19.6)%. After 12 months of GLP1-RA treatment, a total body weight, BMI, and percentage excess body weight reduction of 10.5 (6.1, 14.7) kg, 3.7 (2.5, 5.3) kg/m2, and 41.7 (22.1, 70.5)% were observed, corresponding to a loss of 99.3 (61.0, 135.4)% of the weight regained (P-value < 0.0001). The observed reduction in BMI was significantly lower with liraglutide than with semaglutide, 3.1 (2.0, 4.7) vs. 4.7 (3.7, 6.0) kg/m2 (P-value = 0.04). Adverse events were reported in 13 (32.5%) patients, all of which were mild and transient.

CONCLUSION

GLP1-RA therapy with liraglutide or semaglutide for 12 months is efficacious and safe for the treatment of weight regain following bariatric surgery.

CLINICAL TRIAL NUMBER

Not applicable.

Novel pharmacotherapies for weight loss: Understanding the role of incretins to enable weight loss and improved health outcomes

Obesity and type 2 diabetes mellitus (T2D) are widespread diseases that significantly impact cardiovascular and renal morbidity and mortality. In the recent years, intensive research has been performed to assess the role of adipose tissue and body fat distribution in the development of metabolic and non-metabolic complications in individuals with obesity. In addition to lifestyle modifications, glucagon-like peptide-1 receptor agonists (GLP-1-RA) have become a meaningful treatment expansion for the management of both disorders. In addition to improving metabolic control and reducing body weight, treatment with GLP-1-RAs reduces cardiovascular and renal events in individuals with obesity with and without diabetes. These important benefits of GLP-1-RAs have triggered new interest in other enteroendocrine and enteropancreatic peptides for treating obesity and its metabolic and non-metabolic consequences. The first peptide dual-agonist targeting glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 receptors has been approved for the treatment of T2D and obesity. GIP/GLP-1 dual-agonism appear to provide better metabolic control and greater weight reduction compared with GLP-1-R mono-agonism. Other peptide and non-peptide co-agonists are in clinical development for obesity, T2D, metabolic dysfunction-associated steatotic liver disease (MASLD) and other metabolic disorders. This narrative review aims to summarize the available data on approved and emerging enteroendocrine and enteropancreatic based treatment approaches for obesity and metabolic disorders. In addition to available clinical efficacy measures, side effects, limitations and open challenges will also be addressed.

Advance Insulin Injection Technique and Education With FITTER Forward Expert Recommendations

Injectable insulin therapy is a valuable therapeutic option for millions of people with diabetes worldwide. However, many people with diabetes undergoing insulin therapy experience suboptimal outcomes and/or have complications because of inadequate injection technique and training. Practical, current, evidence-based recommendations are mandatory for primary care practitioners and diabetes specialists alike to address unmet needs in insulin injection technique, education, and consequent outcomes. The most recent global insulin injection technique best practices were published in 2016 by the Forum for Injection Technique and Therapy Expert Recommendations (FITTER). While injection technique efforts in different regions have reflected some developments since 2016, a global effort was warranted to comprehensively capture new evidence and modern expert perspectives. In this article, we share the output of the "FITTER Forward" initiative, authored by 16 diabetes specialists from 13 countries who met virtually in 2023-2024. FITTER Forward provides an updated rationale for the importance of proper injection technique training and its impact on diabetes management. The FITTER Forward recommendations are organized for use in clinical practice and include 4 sections describing (1) the foundational science informing injection device design, experiences, and outcomes, (2) proper injection technique procedures for insulin pens and syringes from insulin storage to needle disposal, (3) lipodystrophy risk reduction, with a focus on lipohypertrophy, and (4) structured injection technique training programs for people with diabetes. Overall, FITTER Forward aims to better equip health care professionals to advance diabetes care by empowering people with diabetes and their caregivers to correctly and safely deliver insulin.

The safety, tolerability, pharmacokinetics and pharmacodynamics of an optimized dual GLP-1/GIP receptor agonist (BGM0504) in healthy volunteers: A dose-escalation Phase I study

OBJECTIVE

Previous experiments have demonstrated that BGM0504, a GLP-1R/GIPR dual agonist drug by molecular dynamics-guided optimization, had enhanced agonistic activity compared to tirzepatide. This study aims to investigate its safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) in Chinese healthy volunteers.

METHODS

A randomized, double-blind, placebo-controlled and dose-escalation Phase I study was conducted as follows: a single dose (2.5 mg) and once-weekly administration for 2 weeks to reach target doses (5, 10 and 15 mg) by titration.

RESULTS

A total of 40 volunteers received at least one dose of BGM0504 or placebo. The PK profile of BGM0504 was investigated over a wide dose range and supported once-weekly administration. It was observed that Cmax and AUC of BGM0504 were linearly proportional to the dose from 2.5-15 mg. The change in body weight (%) from baseline in BGM0504 groups was greater than that in the placebo group, with -3.24%, -6.26%, -7.09% and - 8.30% in 2.5, 5, 10 and 15 mg groups, respectively, indicating a certain dose correlation. Meanwhile, the potential roles of BGM0504 in glycaemic control were also observed. The most frequent adverse events reported were gastrointestinal (vomiting, nausea, decreased appetite, diarrhoea and abdominal distension).

CONCLUSION

BGM0504 was generally safe and well tolerated with favourable PK profile and potential role in weight loss was also confirmed. These findings support subsequent development of BGM0504 for type 2 diabetes mellitus (T2DM) and obesity.

Effects of antidiabetic agents on lipid metabolism of skeletal muscle: A narrative review

Metabolic syndrome-related diseases frequently involve disturbances in skeletal muscle lipid metabolism. The accumulation of lipid metabolites, lipid-induced mitochondrial stress in skeletal muscle cells, as well as the inflammation of adjacent adipose tissue, are associated with the development of insulin resistance and metabolic dysfunction. Consequently, when antidiabetic medications are used to treat various chronic conditions related to hyperglycaemia, the impact on skeletal muscle lipid metabolism should not be overlooked. However, current research has predominantly focused on muscle mass rather than skeletal muscle lipid metabolism and its interplay with glucose metabolism. In this review, we summarised the latest research on the effects of antidiabetic drugs and certain natural compounds with antidiabetic activity on skeletal muscle lipid metabolism, focusing on data from preclinical to clinical studies. Given the widespread use of antidiabetic drugs, a better understanding of their effects on skeletal muscle lipid metabolism merits further attention in future research.

Cardioprotective benefits of metabolic surgery and GLP-1 receptor agonist-based therapies

Individuals with excessive adipose tissue and type 2 diabetes mellitus (T2DM) face a heightened risk of cardiovascular morbidity and mortality. Metabolic surgery is an effective therapy for people with severe obesity to achieve significant weight loss. Additionally, metabolic surgery improves blood glucose levels and can lead to T2DM remission, reducing major adverse cardiovascular outcomes (MACE). Glucagon-like peptide 1 (GLP-1) receptor agonists (GLP-1RAs) are a class of medication that effectively reduce body weight and MACE in patients with T2DM. This review explores the potential mechanisms underlying the cardioprotective benefits of metabolic surgery and GLP-1RA-based therapies and discusses recent evidence and emerging therapies in this dynamic area of research.

Comparison of the effectiveness and safety of GLP-1 receptor agonists for type 2 diabetes mellitus patients with overweight/obesity: A systematic review and network meta-analysis

OBJECTIVE

To evaluate the effectiveness and safety of different Glucagon-like peptide-1 receptor agonists (GLP-1RAs) in treating type 2 diabetes mellitus (T2DM) with overweight/obesity using a systematic review and network meta-analysis.

METHODS

We searched PubMed, Embase, Cochrane Library, and Web of Science up to December 20, 2024, for randomized controlled trials (RCTs) involving T2DM patients with overweight/obesity treated with GLP-1RAs, with the control group receiving either a placebo or another GLP-1RA. We conducted a network meta-analysis assessed evidence using CINeMA.

RESULTS

A total of 4548 articles were retrieved, and 41 RCTs were included, comprising 15,126 patients and 13 different GLP-1RAs. Tirzepatide showed superior effects in lowering blood glucose (Compared with placebo, increased glycated hemoglobin: -1.64 (-1.94, -1.35), increased fasting blood glucose: -2.10 (-2.95, -1.25)) and weight loss (Compared with placebo, increased weight: -9.89 (-11.29, -8.49), rincreased BMI: -3.85 (-4.71, -2.99)). However, clinical efficacy of GLP-1RAs in lipid levels, blood pressure, and pancreatic function was not widely observed. Adverse reactions were significant with GLP-1RAs, but overall acceptable.

CONCLUSION

GLP-1RAs demonstrate efficacy and safety in T2DM patients with overweight/obesity, with certain advantages over other drugs. However, due to limitations in the number and quality of included studies, conclusions should be interpreted with caution.

A once-daily GLP-1/GIP/glucagon receptor tri-agonist (NN1706) lowers body weight in rodents, monkeys and humans

Single molecules that combine complementary modes of action with glucagon-like peptide-1 receptor (GLP-1R) agonism are best-in-class therapeutics for obesity treatment. NN1706 (MAR423, RO6883746) is a fatty-acylated tri-agonist designed for balanced activity at GLP-1R and glucose-dependent insulinotropic peptide receptor (GIPR) with lower relative potency at the glucagon receptor (GcgR). Obese mice, rats and non-human primates dosed with NN1706 showed significant body weight reductions and improved glycemic control. In human participants with overweight or obesity, daily subcutaneous NN1706 treatment resulted in substantial body weight loss in a dose-dependent manner without impairing glycemic control (NCT03095807, NCT03661879). However, increased heart rate was observed across NN1706 treatment cohorts, which challenges further clinical development of NN1706.

Renoprotective mechanisms of glucagon-like peptide-1 receptor agonists

Glucagon-like peptide-1 (GLP-1) is an incretin hormone, secreted from gut endocrine cells, which acts to potentiate nutrient-induced insulin secretion. Activation of its receptor, GLP-1R, decreases glucagon secretion and gastric emptying, thereby decreasing blood glucose and body weight. It is largely through these mechanisms that Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have transformed the treatment of type 2 diabetes. More recently, preclinical and clinical studies have reported that these agents have potent extra-pancreatic effects, exhibiting cardioprotective and renoprotective actions. The recent FLOW trial was the first multicentre clinical trial investigating the effect of GLP-1RAs on a primary renal outcome and reported robust evidence that GLP-1RAs are renoprotective. Studies in rodent models of renal injury have shown that gain and loss of GLP-1R signalling improves or deteriorates kidney function. However, the precise mechanisms responsible for renal benefits of GLP-1RAs are not yet fully understood. While prolonged activation of GLP-1 receptors (GLP-1R) has been shown to reverse diabetes-related disruptions in gene expression across various renal cell populations, GLP-1R expression in both rodent and human kidneys is thought to be primarily confined to certain vascular smooth muscle cells. This review discusses recent advances in our understanding of the effects of GLP-1 medicines on the kidney with a focus on indirect and direct mechanisms of action.

What is the pipeline for future medications for obesity?

Obesity is a chronic disease associated with increased risk of obesity-related complications and mortality. Our better understanding of the weight regulation mechanisms and the role of gut-brain axis on appetite has led to the development of safe and effective entero-pancreatic hormone-based treatments for obesity such as glucagon-like peptide-1 (GLP-1) receptor agonists (RA). Semaglutide 2.4 mg once weekly, a subcutaneously administered GLP-1 RA approved for obesity treatment in 2021, results in 15-17% mean weight loss (WL) with evidence of cardioprotection. Oral GLP-1 RA are also under development and early data shows similar WL efficacy to semaglutide 2.4 mg. Looking to the next generation of obesity treatments, combinations of GLP-1 with other entero-pancreatic hormones with complementary actions and/or synergistic potential (such as glucose-dependent insulinotropic polypeptide (GIP), glucagon, and amylin) are under investigation to enhance the WL and cardiometabolic benefits of GLP-1 RA. Tirzepatide, a dual GLP-1/GIP receptor agonist has been approved for glycaemic control in type 2 diabetes as well as for obesity management leading in up to 22.5% WL in phase 3 obesity trials. Other combinations of entero-pancreatic hormones including cagrisema (GLP-1/amylin RA) and the triple agonist retatrutide (GLP-1/GIP/glucagon RA) have also progressed to phase 3 trials as obesity treatments and early data suggests that may lead to even greater WL than tirzepatide. Additionally, agents with different mechanisms of action to entero-pancreatic hormones (e.g. bimagrumab) may improve the body composition during WL and are in early phase clinical trials. We are in a new era for obesity pharmacotherapy where combinations of entero-pancreatic hormones approach the WL achieved with bariatric surgery. In this review, we present the efficacy and safety data for the pipeline of obesity pharmacotherapies with a focus on entero-pancreatic hormone-based treatments and we consider the clinical implications and challenges that the new era in obesity management may bring.

Does Improvement of Glycemic Control Cause Acute Charcot Foot in Patients with Diabetes?

Recent studies have suggested that improved glycemic control in patients with diabetes may cause acute Charcot foot. To conduct a narrative review of studies investigating whether improved glycemic control in patients with diabetes causes acute Charcot foot.Publications found by searching PubMed, EMBASE, and Cochrane Library as well as reference lists of identified publications were reviewed.Very few publications were found, primarily consisting of case reports and case studies without control groups, documenting instances where cases of acute Charcot foot had been preceded by improved glycemic control. Recent large multicenter randomized placebo-controlled clinical trials of anti-hyperglycemic agents in patients with diabetes, where significant improvement of glycemic control occurred, have not reported incidences of acute Charcot foot.There is so far no solid evidence to suggest that improvement of glycemic control in patients with diabetes causes acute Charcot foot.

Structured lifestyle modification as an adjunct to obesity pharmacotherapy: there is much to learn

We are at the start of an exciting new era of very effective pharmacotherapy for patients with obesity, with the latest generation of drugs approaching the efficacy of obesity surgery. Clinical trials of obesity drugs tend to emphasise the importance of participation in some form of structured lifestyle intervention for all trial participants. This usually consists of advice to reduce calorie intake and increase moderate to vigorous physical activity. There is strong evidence that structured lifestyle modification programmes improve health in patients with obesity and related disorders. However, there is no specific evidence that they improve the response to obesity medications. This is because of the way that drug trials for patients with obesity have traditionally been designed, with participants in the active drug treatment group being compared to participants on placebo drug treatment, but with both groups always receiving the same structured lifestyle intervention. While this approach is entirely reasonable, it makes it impossible to draw any inferences about the efficacy of structured lifestyle modification to augment the response to drug therapy. Given this genuine equipoise, a critical step in ensuring that our treatment of patients with obesity is robustly evidence-based is to determine whether "drug plus lifestyle" offer any advantage over "drug plus placebo" in large, well-designed and adequately powered clinical trials. We also need to determine the cost-effectiveness of these programmes.

Obesity pharmacotherapy in older adults: a narrative review of evidence

The prevalence of obesity in older adults (people aged >60 years) is increasing in line with the demographic shift in global populations. Despite knowledge of obesity-related complications in younger adults (increased risk of type 2 diabetes, liver and cardiovascular disease and malignancy), these considerations may be outweighed, in older adults, by concerns regarding weight-loss induced reduction in skeletal muscle and bone mass, and the awareness of the 'obesity paradox'. Obesity in the elderly contributes to various obesity-related complications from cardiometabolic disease and cancer, to functional decline, worsening cognition, and quality of life, that will have already suffered an age-related decline. Lifestyle interventions remain the cornerstone of obesity management in older adults, with emphasis on resistance training for muscle strength and bone mineral density preservation. However, in older adults with obesity refractory to lifestyle strategies, pharmacotherapy, using anti-obesity medicines (AOMs), can be a useful adjunct. Recent evidence suggests that intentional weight loss in older adults with overweight and obesity is effective and safe, hence a diminishing reluctance to use AOMs in this more vulnerable population. Despite nine AOMs being currently approved for the treatment of obesity, limited clinical trial evidence in older adults predominantly focuses on incretin therapy with glucagon-like peptide-1 receptor agonists (liraglutide, semaglutide, and tirzepatide). AOMs enhance weight loss and reduce cardiometabolic events, while maintaining muscle mass. Future randomised controlled trials should specifically evaluate the effectiveness of novel AOMs for long-term weight management in older adults with obesity, carefully considering the impact on body composition and functional ability, as well as health economics.

The promise of glucagon-like peptide 1 receptor agonists (GLP-1RA) for the treatment of obesity: a look at phase 2 and 3 pipelines

INTRODUCTION

GLP-1-based therapies have changed the treatment of overweight/obesity. Liraglutide 3.0 mg daily, the first GLP-1 RA approved for treatment of overweight, induced a weight loss of 6-8%, Semaglutide 2.4 mg once weekly improved weight loss to about 12-15%, while the dual GIP/GLP-1 receptor agonist tirzepatide once weekly has induced a weight loss of about 20% in obese people without diabetes.

AREAS COVERED

This review describes results obtained with GLP-1 mono-agonists, GLP-1/GIP dual agonists, GLP-1/glucagon co-agonists, and the triple agonist retatrutide (GIP/GLP-1/glucagon), which have shown beneficial effect both on body weight and steatotic liver disease. A combination of semaglutide (a GLP-1 agonist) and cagrilintide (a long-acting amylin analogue) for weekly administration is currently in phase III development, and so is oral semaglutide and several non-peptide small molecule GLP-1 agonists for oral administration. The adverse events with the GLP-1-based therapies are primarily gastrointestinal and include nausea, vomiting, obstipation, or diarrhea, which often can be mitigated by slow up titration.

EXPERT OPINION

The GLP-1-based therapies will change the treatment of obesity and its comorbidities including steatotic liver disease in the future. Outstanding question is maintenance of the weight loss, possibly pharmacological treatment needs to be life-long.

Trending Modalities in Type 2 Diabetes Prevention

CONTEXT

Prediabetes now affects a substantial proportion of the population, marking a growing group of individuals at increased risk for the development of type 2 diabetes (T2D). Given the profound effect of T2D on an individual's morbidity and mortality, T2D prevention is of critical importance.

EVIDENCE ACQUISITION

We searched PubMed and Ovid MEDLINE databases for recent systematic reviews, meta-analyses, and original research articles pertaining to prediabetes and the prevention of T2D.

EVIDENCE SYNTHESIS

T2D prevention strategies have focused on intensive lifestyle modification as well as numerous medications that ultimately improve insulin resistance. Recently, a better understanding of the gut microbiome's role in diabetes progression has suggested a possible preventive role for fecal transplant. Finally, multiple incretin pharmaceutical agents have been developed that show promise in the prevention and treatment of T2D.

CONCLUSION

The number of novel ways to prevent T2D is rapidly growing. A thorough understanding of the indications, outcomes, and limitations of these new therapies is critical for all who care for individuals with diabetes.

GLP-1-based therapies for type 2 diabetes: from single, dual and triple agonists to endogenous GLP-1 production and L-cell differentiation

Glucagon-like peptide-1 (GLP-1) is an incretin peptide hormone mainly secreted by enteroendocrine intestinal L-cells. GLP-1 is also secreted by α-cells of the pancreas and the central nervous system (CNS). GLP-1 secretion is stimulated by nutrient intake and exerts its effects on glucose homeostasis by stimulating insulin secretion, gastric emptying confiding the food intake, and β-cell proliferation. The insulinotropic effects of GLP-1, and the reduction of its effects in type 2 diabetes mellitus (T2DM), have made GLP-1 an attractive option for the treatment of T2DM. Furthermore, GLP-1-based medications such as GLP-1 receptor agonists and dipeptidyl peptidase-4 inhibitors, have been shown to improve diabetes control in preclinical and clinical trials with human subjects. Importantly, increasing the endogenous production of GLP-1 by different mechanisms or by increasing the number of intestinal L-cells that tend to produce this hormone may be another effective therapeutic approach to managing T2DM. Herein, we briefly describe therapeutic agents/compounds that enhance GLP-1 function. Then, we will discuss the approaches that can increase the endogenous production of GLP-1 through various stimuli. Finally, we introduce the potential of L-cell differentiation as an attractive future therapeutic approach to increase GLP-1 production as an attractive therapeutic alternative for T2DM.

Focus on Glucagon-like Peptide-1 Target: Drugs Approved or Designed to Treat Obesity

Obesity is closely related to metabolic diseases, which brings a heavy burden to the health care system. It is urgent to formulate and implement effective treatment strategies. Glucagon-like peptide-1 (GLP-1) is a protein with seven transmembrane domains connected by type B and G proteins, which is widely distributed and expressed in many organs and tissues. GLP-1 analogues can reduce weight, lower blood pressure, and improve blood lipids. Obesity, diabetes, cardiovascular diseases, and other diseases have caused scientists' research and development boom. Among them, GLP-1R agonist drugs have developed rapidly in weight-loss drugs. In this paper, based on the target of GLP-1, the mechanism of action of GLP-1 in obesity treatment was deeply studied, and the drugs approved and designed for obesity treatment based on GLP-1 target were elaborated in detail. Innovatively put forward and summarized the double and triple GLP-1 targeted drugs in the treatment of obesity with better effects and less toxic and side effects, and this can make full use of multi-target methods to treat other diseases in the future. Finally, it is pointed out that intestinal flora and microorganisms have many benefits in the treatment of obesity, and fecal bacteria transplantation may be a potential treatment for obesity with less harm to the body. This article provides some promising methods to treat obesity, which have strong practical value.

Innovative Drugs First Implemented in Type 2 Diabetes Mellitus and Obesity and Their Effects on Metabolic Dysfunction-Associated Steatohepatitis (MASH)-Related Fibrosis and Cirrhosis

Metabolic dysfunction-associated steatotic liver disease (MASLD), a progressive liver disease frequently associated with metabolic disorders such as type 2 diabetes mellitus (T2DM) and obesity, has the potential to progress symptomatically to liver cirrhosis and, in some cases, hepatocellular carcinoma. Hence, an urgent need arises to identify and approve new therapeutic options to improve patient outcomes. Research efforts have focused on either developing dedicated molecules or repurposing drugs already approved for other conditions, such as metabolic diseases. Among the latter, antidiabetic and anti-obesity agents have received the most extensive attention, with pivotal trial results anticipated shortly. However, the primary focus underlying successful regulatory approvals is demonstrating a substantial efficacy in improving liver fibrosis and preventing or ameliorating cirrhosis, the key advanced outcomes within MASLD progression. Besides liver steatosis, the ideal therapeutic candidate should reduce inflammation and fibrosis effectively. Although some agents have shown promise in lowering MASLD-related parameters, evidence of their impact on fibrosis and cirrhosis remains limited. This review aims to evaluate whether antidiabetic and anti-obesity drugs can be safely and effectively used in MASLD-related advanced fibrosis or cirrhosis in patients with T2DM. Our paper discusses the molecules closest to regulatory approval and the expectation that they can address the unmet needs of this increasingly prevalent disease.

Quantitative Comparison of Glucagon-Like Peptide-1 Receptor Agonists on Weight Loss in Adults: A Systematic Review and Model-Based Meta-Analysis

The objective of this study is to quantitatively compare the weight loss effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) in adult patients with no diabetes and type 2 diabetes (T2D). PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase have been used as data sources from database inception to January 6, 2024. A total of 137 trials, encompassing 310 treatment arms, 17 GLP-1RAs, and 56,683 patients, were included in the analysis. The included trials were divided into three groups based on the characteristics of the populations: nondiabetic overweight or obesity group (NDOOG), type 2 diabetes Caucasian group (T2DCG), and type 2 diabetes Asian group (T2DAG). The effects of covariates were further evaluated, patients with a higher baseline body weight tend to have better weight loss outcomes, and patients with a higher baseline glycated hemoglobin (HbA1c) tend to achieve better blood sugar control. Five mathematical models were subjected to longitudinal analysis. In terms of Δ body weight, retatrutide (12 mg qw) was the most effective treatment (mean difference = -26.56% [95% confidence interval: -43.89% to -3.01%]). Tirzepatide (15 mg qw) demonstrated good weight loss ability in all three ΔBW models, ΔBW-NDOOG (-22.76% [-26.45% to -18.50%]), ΔBW-T2DCG (-11.09% [-12.39% to -9.44%])), and ΔBW-T2DAG (-4.97% [-5.84% to -4.12%]). In the aspect of ΔHbA1c, tirzepatide (10 mg qw) and oral orforglipron (10 mg qd) were the most effective drug, respectively. GLP-1RAs demonstrated effective weight management in both nondiabetic and T2D populations. Retatrutide achieved the most pronounced weight reduction, followed by tirzepatide. GLP-1RAs also significantly improved glycemic control for patients with T2D, with tirzepatide performing the best for glycemic control.

Comparative efficacy of incretin drugs on glycemic control, body weight, and blood pressure in adults with overweight or obesity and with/without type 2 diabetes: a systematic review and network meta-analysis

Background

The rapid development of multi-receptor drugs targeting glucagon-like peptide-1 receptor (GLP-1R) is driving significant advancements in the treatment of individuals with type 2 diabetes and obesity. This systematic review and network meta-analysis aims to compare the efficacy and safety of multi-receptor drugs in adults with overweight or obesity, with or without type 2 diabetes.

Methods

A systematic search was conducted in PubMed, Cochrane, Web of Science, Embase, CNKI, and WanFang databases up to May 12, 2024. Randomized controlled trials (RCTs) with an intervention duration of at least 12 weeks were included. The population of interest consisted of individuals with overweight or obesity, with or without type 2 diabetes. Eligible studies compared multi-receptor drugs with placebo or other multi-receptor drugs. The primary outcomes were weight reduction, glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), blood pressure changes, and adverse events. Risk of bias was assessed using the version 2 of the Cochrane risk-of-bias tool (ROB2), and a random-effects network meta-analysis was performed using the frequentist approach. Confidence in effect estimates was evaluated using the Confidence In Network Meta-Analysis (CINeMA) framework.

Results

A total of 24 trials, involving 9165 participants, were included. Retatrutide (mean difference (MD): -11.91 kg, 95% CI: -19.00 to -4.82, P-score: 0.80, p: 0.0003) and Tirzepatide (MD: -12.78 kg, 95% CI: -16.10 to -9.46, P-score: 0.89, p < 0.0001) exhibited superior efficacy in reducing body weight, with all other agents except Mazdutide (MD: -5.31 kg, 95% CI: -9.78 to -0.84, P-score: 0.37, p: 0.0189) achieving reductions of over 8 kg. In patients with type 2 diabetes, all agents reduced HbA1c by over 1%, with Tirzepatide (MD: -1.87%, 95% CI: -2.15 to -1.59, P-score: 0.87, p < 0.0001) and Mazdutide (MD: -1.89%, 95% CI: -2.43 to -1.35, P-score: 0.88, p < 0.0001) showing the greatest effects on glycemic control. For blood pressure management, Tirzepatide significantly reduced systolic blood pressure (MD: -6.69 mmHg, 95% CI: -7.62 to -5.75, P-score: 0.84, p < 0.0001) and diastolic blood pressure (MD: -3.73 mmHg, 95% CI: -4.75 to -2.71, P-score: 0.92, p < 0.0001), with nearly all agents lowering systolic blood pressure by more than 5 mmHg. Non-diabetic participants showed more pronounced improvements in both weight and blood pressure. Safety analysis revealed that Tirzepatide had a favorable safety profile and all agents showed no significant impact on serious adverse events compared to placebo.

Conclusions

Multi-receptor drugs demonstrated substantial therapeutic potential in weight management, glycemic control, and blood pressure regulation in adults with overweight or obesity, with or without diabetes, with a generally favorable safety profile.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024554005.

Hormonal regulation of human adipose tissue lipolysis: impact of adipose GIP system in overweight and obesity

OBJECTIVE

Given the promising effects of GLP-1/GIP/glucagon receptor triagonists on weight loss in animals and humans, improved understanding of underlying mechanism is required. We investigated a direct lipolytic effect of a specific GLP-1/GIP/glucagon receptor triagonist on human adipose tissue to disentangle central and peripheral effects as potential drivers of weight loss.

DESIGN AND METHODS

Isolated primary adipocytes from subcutaneous adipose tissue biopsies of 22 non-diabetic subjects [63.0 (57.0-69.5) years] were incubated with increasing concentrations of isoprenaline, GLP-1, GIP, glucagon, or a GLP-1/GIP/glucagon receptor triagonist. Glycerol concentration was measured following stimulation to assess lipolysis. mRNA expression of adipose tissue receptors was analyzed in parallel.

RESULTS

Glycerol concentration only increased by isoprenaline, GIP (+13%), and GLP-1/GIP/glucagon receptor triagonist (+28%) but not by GLP-1 or glucagon. This effect was not related to age or body mass index (BMI). Higher adipose tissue GIP receptor mRNA expression was related to elevated glycerol release after GIP and GLP-1/GIP/glucagon receptor triagonist stimulation.

CONCLUSIONS

Direct lipolytic effects of GIP seem to exist in human subcutaneous adipose tissue. This might be targetable by multiple receptor agonists, especially with a high GIP receptor affinity. Such a mechanism can potentiate the beneficial effect on weight loss and will therefore represent a promising target of future research.

CLINICAL TRIAL REGISTRATION NUMBER

The trial was registered at German Clinical Trials Register (drks.de) as DRKS00010049.

Overview of diabetes agents in cardiovascular disease: it takes an orchestra to play Tchaikovsky in symphony

PURPOSE OF REVIEW

The aim of this review was to discuss the use and concerns of diabetes agents, clinical targets, and key aspects to be considered in the management of patients with type 2 diabetes mellitus (T2DM), and at high risk or established cardiovascular disease (CVD).

RECENT FINDINGS

The recent European and American guidelines recommended SGLT2 inhibitors and GLP-1 receptor agonists as the preferred first-line diabetes agents in patients with T2DM and CVD. This is a paradigm shift from using metformin as first-line therapy. Amid their widespread use, however, there are also concerns about their side effects. With the rapidly growing diabetes regimens available, questions arise about how best to approach the management of patients with T2DM and CVD.

SUMMARY

To reduce CVD morbidity and mortality in patients with T2DM and at high or very high risk for CVD, the two key diabetes agents SGLT2i and/or GLP1-based therapies should be offered. Although lacking cardiovascular benefit, other diabetes agents remain necessary for many patients with T2DM for their glucocentric effects; Metformin and pioglitazone are useful in severe insulin resistance, while insulin therapy is often necessary in advanced diabetes; GLP1-RA is cautioned in patients with active gastrointestinal and mental health conditions, while DPP4 inhibitor is likely a well tolerated option in a challenging psychosocial setting. Other important aspects that should be considered include obesity, chronic kidney disease, women's cardiovascular health, and psychosocial factors.

Glucagon like peptide-1 (GLP-1) agonists and cardiometabolic protection: historical development and future challenges

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have revolutionized the treatment of cardiometabolic diseases, extending their therapeutic applications far beyond glycemic control in type 2 diabetes (T2D) and obesity. This editorial synthesizes key milestones, from the discovery of GLP-1 to recent clinical trials highlighting the pleiotropic effects of GLP-1RAs in addressing the interconnected spectrum of cardiometabolic conditions, with a focus on cardiovascular, renal, and hepatic benefits. In addition, as GLP-1RAs continue to reshape the management of cardiometabolic disease and global public health, we discuss future challenges to better elucidate their mechanisms of cardiometabolic protection and maximize their therapeutic potential.

Adipocentric Strategy for the Treatment of Type 2 Diabetes Mellitus

The global prevalence of obesity and type 2 diabetes mellitus (T2D) has risen in parallel over recent decades. Most individuals diagnosed with T2D exhibit adiposopathy-related diabetes (ARD), a condition characterized by hyperglycemia accompanied by three core features: increased ectopic and visceral fat deposition, dysregulated adipokine secretion favoring a pro-inflammatory state, and insulin resistance. Despite advancements in precision medicine, international guidelines for T2D continue to prioritize individualized therapeutic approaches focused on glycemic control and complications, and many healthcare providers predominantly maintain a glucocentric strategy. This review advocates for an adipocentric treatment paradigm for most individuals with T2D, emphasizing the importance of prioritizing weight loss and visceral fat reduction as key drivers of therapeutic intensification. By combining lifestyle modifications with pharmacological agents that promote weight loss-including SGLT-2 inhibitors, GLP-1 receptor agonists, or dual GLP-1/GIP receptor agonists-and, when appropriate, metabolic surgery, this approach offers the potential for disease remission in patients with shorter disease duration. For others, it enables superior metabolic control compared to traditional glucose-centered strategies while simultaneously delivering cardiovascular and renal benefits. In conclusion, an adipocentric treatment framework for ARD, which represents the majority of T2D cases, effectively integrates glucocentric and cardio-nephrocentric goals. This approach constitutes the optimal strategy for ARD due to its efficacy in achieving disease remission, improving metabolic control, addressing obesity-related comorbidities, and reducing cardiovascular and renal morbidity and mortality.

A perspective on intermittent fasting and cardiovascular risk in the era of obesity pharmacotherapy

Intermittent fasting has been linked to metabolic health by improving lipid profiles, reducing body weight, and increasing insulin sensitivity. However, several randomized clinical trials have shown that intermittent fasting is not more effective than standard daily caloric restriction for short-term weight loss or cardiometabolic improvements in patients with obesity. Observational studies also suggest cardiovascular benefits from extended rather than reduced eating windows, and indicate that long-term intermittent fasting regimens may increase the risk of cardiovascular disease mortality. In this perspective, we discuss evidence that may support potential adverse effects of intermittent fasting on cardiovascular health through the loss of lean mass, circadian misalignment and poor dietary choices associated with reward-based eating. Given the ongoing revolution in obesity pharmacotherapy, we argue that future research should integrate anti-obesity medications with dietary strategies that confer robust benefits to cardiometabolic health, combine exercise regimens, and consider genetic factors to personalize obesity treatment. Comprehensive approaches combining diet, pharmacotherapy, and lifestyle modifications will become crucial for managing obesity and minimizing long-term cardiovascular risk.

Investigating the impact of microbiome-changing interventions on food decision-making: MIFOOD study protocol

BACKGROUND

Obesity is a multifactorial disease reaching pandemic proportions with increasing healthcare costs, advocating the development of better prevention and treatment strategies. Previous research indicates that the gut microbiome plays an important role in metabolic, hormonal, and neuronal cross-talk underlying eating behavior. We therefore aim to examine the effects of prebiotic and neurocognitive behavioral interventions on food decision-making and to assay the underlying mechanisms in a Randomized Controlled Trial (RCT).

METHOD

This study uses a parallel arm RCT design with a 26-week intervention period. We plan to enroll 90 participants (male/diverse/female) living with overweight or obesity, defined as either a Waist-to-Hip Ratio (WHR) ≥ 0.9 (male)/0.85 (diverse, female) or a Body Mass Index (BMI) ≥ 25 kg/m2. Key inclusion criteria are 18-60 years of age and exclusion criteria are type 2 diabetes, psychiatric disease, and Magnetic Resonance Imaging (MRI) contraindications. The interventions comprise either a daily supplementary intake of 30 g soluble fiber (inulin), or weekly neurocognitive behavioral group sessions, compared to placebo (equicaloric maltodextrin). At baseline and follow-up, food decision-making is assessed utilizing task-based MRI. Secondary outcome measures include structural MRI, eating habits, lifestyle factors, personality traits, and mood. Further, we obtain fecal and blood samples to investigate gut microbiome composition and related metabolites.

DISCUSSION

This study relies on expanding research suggesting that dietary prebiotics could improve gut microbiome composition, leading to beneficial effects on gut-brain signaling and higher-order cognitive functions. In parallel, neurocognitive behavioral interventions have been proposed to improve unhealthy eating habits and metabolic status. However, causal evidence on how these "bottom-up" and "top-down" processes affect food decision-making and neuronal correlates in humans is still scarce. In addition, microbiome, and gut-brain-axis-related mediating mechanisms remain unclear. The present study proposes a comprehensive approach to assess the effects of these gut-brain-related processes influencing food decision-making in overweight and obesity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05353504. Retrospectively registered on 29 April 2022.

Approach to Lipid Management in the Patient with Diabetes

Diabetes is associated with increased atherosclerotic cardiovascular disease (ASCVD) risk, a leading cause of morbidity and mortality. Disordered lipid metabolism is a major contributor to ASCVD risk in diabetes. Dyslipidemia in type 2 diabetes is characterized by hypertriglyceridemia, low HDL cholesterol and the presence of small, dense LDL particles. Statins have demonstrated longstanding benefit for reducing ASCVD risk in individuals with diabetes. Newer agents for add-on therapies to statins are now available for additional cardiovascular risk reduction. In this clinical overview, we review the pathogenesis of dyslipidemia in both types 1 and 2 diabetes and provide an update on the management of lipids in the individual with diabetes. We discuss the importance of appropriate risk stratification, individualized treatment selection, and the need to avoid therapy inertia to mitigate cardiovascular risk. We will also address lipid-related effects of glycemic lowering therapies.

Bile acids and incretins as modulators of obesity-associated atherosclerosis

Obesity is one of the major global health concerns of the 21st century, associated with many comorbidities such as type 2 diabetes mellitus (T2DM), metabolic dysfunction-associated steatotic liver disease, and early and aggressive atherosclerotic cardiovascular disease, which is the leading cause of death worldwide. Bile acids (BAs) and incretins are gut hormones involved in digestion and absorption of fatty acids, and insulin secretion, respectively. In recent years BAs and incretins are increasingly recognized as key signaling molecules, which target multiple tissues and organs, beyond the gastro-intestinal system. Moreover, incretin-based therapy has revolutionized the treatment of T2DM and obesity. This mini review highlights the current knowledge about dysregulations in BA homeostasis in obesity with a special focus on atherosclerosis as well as athero-modulating roles of incretins and currently available incretin-based therapies.

Evolving Global Etiology of Hepatocellular Carcinoma (HCC): Insights and Trends for 2024

The epidemiology of HCC is changing all over the world and the incidence of HCC is expected to continue increasing over the next 30 years. The changes are in the predisposing factors. Hepatitis B and hepatitis C as predisposing etiologies are decreasing while NAFLD/MAFLD is increasing. The increase in MAFLD is so great that despite the decrease in hepatitis B and C, the overall incidence of HCC is increasing. HCC in persons below the age of 20 years has distinct characteristics different from that of HCC in adults. The changing etiology of hepatocellular carcinoma has implications for the early detection, prevention, the stage of HCC at time of detection and in the treatment of HCC. The extent of these changes and their significance are discussed.

Comparison of the effects of Liraglutide, Tirzepatide, and Retatrutide on diabetic kidney disease in db/db mice

PURPOSE

To assess and compare the therapeutic efficacy of Liraglutide, Tirzepatide, and Retatrutide in treating diabetic kidney disease (DKD) in db/db mice.

METHODS

Db/db mice were administered intraperitoneal injections of Liraglutide (10 nmol/kg), Tirzepatide (10 nmol/kg), and Retatrutide (10 nmol/kg) for 10 weeks. Subsequently, we assessed the effectiveness of these three drugs in controlling blood glucose levels, reducing weight, and improving serum biochemical indicators and DKD. Additionally, we measured and compared the renal inflammation and fibrosis indexes. Meanwhile, the content of intestinal metabolite butyrate was compared to reflect the regulatory effects of these three drugs on gut microbiota.

RESULTS

Retatrutide demonstrated superior effectiveness in reducing weight and improving renal function in db/db mice compared to Liraglutide and Tirzepatide. Additionally, it markedly suppressed the expression of pro-inflammatory cytokines (TNF-α, caspase-1, and NLRP3) and pro-fibrotic factors (fibronectin, α-SMA, and collagen I) in the kidneys of mice. Furthermore, Retatrutide substantially enhanced liver function, reduced triglyceride levels, cholesterol levels, low-density lipoprotein cholesterol, elevated high-density lipoprotein cholesterol, and increased the content of intestinal metabolite butyrate in db/db mice when compared to the other two drugs. Unfortunately, despite its ability to lower blood glucose levels, Retatrutide did not outperform the other two drugs. In contrast, Tirzepatide exhibited better effects on lowering blood glucose, weight loss, lipid reduction, and improvement of DKD compared to Liraglutide.

CONCLUSIONS

Retatrutide and Tirzepatide were significantly effective in improving DKD, controlling blood glucose and body weight. Retatrutide was the most effective in improving DKD and body weight, while Tirzepatide was the most effective in controlling blood glucose. Inhibiting the expression of inflammatory factors and fibrosis mediators and regulating intestinal microbiota may be the potential mechanisms of these two drugs to delay the progression of DKD.

Characterization of LY3324954 a long-acting glucagon-receptor agonist

OBJECTIVE

Glucagon is a crucial regulator of glucose and lipid metabolism as well as whole-body energy balance. Thus, modulation of glucagon receptor (GCGR) activity in the context of single-molecule multi-receptor co-agonists has become an emerging therapeutic target against obesity and obesity-associated metabolic dysfunction. To better elucidate the role of GCGR-signaling when paired with incretin receptor signaling or on its own, we developed, LY3324954, a GCGR agonist with improved potency and selectivity as compared to the native glucagon peptide.

METHODS

LY3324954 was administered to DIO mice, rats, dogs, and monkeys to evaluate pharmacokinetic (PK) profile. Biweekly treatments were conducted in lean and DIO mice to characterize LY3324954-effects on glucose homeostasis and energy balance. Single dose studies were also conducted in liver Gcgr-deficient mice to establish receptor specificity.

RESULTS

LY3324954 also exhibited extended PK profile in DIO mice, rats, dogs, and monkeys. When administered every 72 h, LY3324954 treatment stimulated transient glucose and insulin excursions in lean mice. In diet-induced obese mice, LY3324954 treatment stimulates energy expenditure, weight loss, and a reduction of adiposity in a dose-dependent manner. Benefit to whole-body lipid homeostasis was likewise observed in these mice.

CONCLUSIONS

Taken together, these studies characterize a long-acting and potent GCGR-agonist and its regulation of glucose and lipid metabolism as well as whole-body energy balance following both acute and chronic treatment in mice.

Incretin-based therapies for the management of cardiometabolic disease in the clinic: Past, present, and future

Among newer classes of drugs for type 2 diabetes mellitus (T2DM), glucagon-like peptide 1 receptor agonists (GLP-1 RAs) are incretin-based agents that lower both blood sugar levels and promote weight loss. They do so by activating pancreatic GLP-1 receptors (GLP-1R) to promote glucose-dependent insulin release and inhibit glucagon secretion. They also act on receptors in the brain and gastrointestinal tract to suppress appetite, slow gastric emptying, and delay glucose absorption. Phase 3 clinical trials have shown that GLP-1 RAs improve cardiovascular outcomes in the setting of T2DM or overweight/obesity in people who have, or are at high risk of having atherosclerotic cardiovascular disease. This is largely driven by reductions in ischemic events, although emerging evidence also supports benefits in other cardiovascular conditions, such as heart failure with preserved ejection fraction. The success of GLP-1 RAs has also seen the evolution of other incretin therapies. Tirzepatide has emerged as a dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RA, with more striking effects on glycemic control and weight reduction than those achieved by isolated GLP-1R agonism alone. This consists of lowering glycated hemoglobin levels by more than 2% and weight loss exceeding 15% from baseline. Here, we review the pharmacological properties of GLP-1 RAs and tirzepatide and discuss their clinical effectiveness for T2DM and overweight/obesity, including their ability to reduce adverse cardiovascular outcomes. We also delve into the mechanistic basis for these cardioprotective effects and consider the next steps in implementing existing and future incretin-based therapies for the broader management of cardiometabolic disease.

Glucagon and glucagon-like peptide-1 dual agonist therapy: A possible future towards fatty kidney disease

BACKGROUND

Obesity is a growing epidemic affecting approximately 40% of the adult population in developed countries with major health consequences and comorbidities, including diabetes mellitus and insulin resistance, metabolically associated fatty liver disease, atherosclerotic cardiovascular and cerebrovascular diseases and chronic kidney disease. Pharmacotherapies targeting significant weight reduction may have beneficial effects on such comorbidities, though such therapeutic options are highly limited. In this narrative review, we aim to evaluate current knowledge regarding dual agonist therapies and potential implications for managing fatty kidney and chronic kidney disease.

RESULTS AND CONCLUSION

Glucagon-like peptide-1 agonists and sodium-glucose cotransporter-2 inhibitors are two novel classes of glucose-lowering medications with potential implications and beneficiary effects on renal outcomes, including estimated glomerular filtration rate, albuminuria and chronic kidney disease progression. Recently, dual agonist therapies targeting glucagon-like peptide-1 and glucagon receptors, namely survodutide and cotadutide, have been evaluated in managing metabolically associated fatty liver disease, a well-established example of visceral obesity. Fatty kidney is another novel concept implicated in the pathophysiology of chronic kidney disease among patients with visceral obesity.

Efficacy and safety of triple hormone receptor agonist retatrutide for the management of obesity: a systematic review and meta-analysis

INTRODUCTION

Retatrutide is a novel triple hormone receptor agonist which has shown great promise in tackling obesity in preliminary trials. We did this systematic review and meta-analysis to pool the results of all available trials and ascertain its safety and efficacy in the treatment of obesity.

MATERIAL AND METHODS

A literature search was conducted in PubMed, Cochrane Central and Embase using appropriate search terms and randomized control trials (RCTs) were identified which reported the safety and efficacy of retatrutide. Data was pooled using mean differences for continuous variables and risk ratios for the safety profile in RStudio.

RESULTS

After the initial search four RCTs were included in the analysis which compared the safety and efficacy of retatrutide versus placebo. Retatrutide showed a dose dependent relationship with the 12 mg dose causing the maximum reductions across all the outcomes considered. The safety profile of retatrutide was found to be comparable to the control group.

CONCLUSION

In conclusion our analysis found retatrutide to be clinically and statistically better than placebo in the various studies outcomes. We eagerly await the conduction of further trials for more robust and substantial results.

PROTOCOL REGISTRATION

www.crd.york.ac.uk/prospero identifier is CRD42024566153.

Weight Loss Blockbuster Development: A Role for Unimolecular Polypharmacology

Obesity and type 2 diabetes mellitus (T2DM) impact more than 2.5 billion adults worldwide, necessitating innovative therapeutic approaches. Unimolecular polypharmacology, which involves designing single molecules to target multiple receptors or pathways simultaneously, has revolutionized treatment strategies. Blockbuster drugs such as tirzepatide and retatrutide have shown unprecedented success in managing obesity and T2DM, demonstrating superior efficacy compared to conventional single agonists. Tirzepatide, in particular, has garnered tremendous attention for its remarkable effectiveness in promoting weight loss and improving glycemic control, while offering additional cardiovascular and renal benefits. Despite their promises, such therapeutic agents also face challenges that include gastrointestinal side effects, patient compliance issues, and body weight rebound after cessation of the treatment. Nonetheless, the development of these therapies marks a significant leap forward, underscoring the transformative potential of unimolecular polypharmacology in addressing metabolic diseases and paving the way for future innovations in personalized medicine.

The power of three: Retatrutide's role in modern obesity and diabetes therapy

The increasing prevalence of obesity and type 2 diabetes mellitus has resulted in a significant challenge to public health throughout the globe. It required the development of novel therapeutic approaches. Retatrutide is a groundbreaking triple agonist that targets glucagon receptors, gastric inhibitory polypeptide, and glucagon-like peptide-1. Retatrutide's complex mechanism of action involves a synergistic interaction among these receptors, resulting in increased insulin secretion, improved glucose homeostasis, and refined appetite modulation. Clinical trials in phases 1 to 3 have demonstrated significant efficacy, highlighted by significant reductions in body weight and favorable glycemic control outcomes. Additionally, retatrutide shows promise in mitigating cardiovascular risk factors and addressing metabolic dysfunction-associated steatotic liver disease. However, careful attention is required to delineate its long-term safety profile, explore its potential in special populations, unravel its adjunctive therapeutic roles, and elucidate its mechanisms in pediatric cohorts. As a transformative therapeutic modality, retatrutide represents a beacon of hope, signifying transformative changes in the management landscape of obesity and type 2 diabetes mellitus (T2DM), and warranting continued exploration and refinement in clinical practice. This narrative review examines the therapeutic potential of retatrutide in the management of obesity and T2DM.

Seven glucagon-like peptide-1 receptor agonists and polyagonists for weight loss in patients with obesity or overweight: an updated systematic review and network meta-analysis of randomized controlled trials

PURPOSE

This study aimed to provide evidence-based support and a reference for the efficacy and safety of seven glucagon-like peptide-1 (GLP-1) receptor agonists and polyagonists for weight loss in patients with obesity or overweight through a network meta-analysis.

METHODS

Relevant randomized controlled trials (RCTs) with an intervention duration of at least 16 weeks assessing seven GLP-1 receptor agonists and polyagonists (mazdutide, 6 or 4.5 mg; retatrutide, 12 or 8 mg; tirzepatide, 15 or 10 mg; liraglutide, 3.0 mg; semaglutide, 2.4 mg; orforglipron, 45 or 36 mg; and beinaglutide, 0.2 mg) in patient with obesity or overweight was searched using three databases (Cochrane Library, PubMed, and Embase) from creation to August 30, 2024. The primary outcome was the percentage change in body weight from baseline. Secondary outcomes included changes in waist circumference, hemoglobin A1c, and fasting plasma glucose level from baseline; adverse events, serious adverse events, adverse event withdrawal, and hypoglycemic events. We conducted a frequentist random-effects network meta-analysis to analyze the data extracted from the RCTs using Stata 16.1 software.

RESULTS

Twenty-seven RCTs of seven GLP-1 receptor agonists and polyagonists and 15,584 patients were included in the network meta-analysis. In terms of efficacy, compared with placebo, retatrutide 12 mg (-22.10 % in body weight and - 17.00 cm in waist circumference), retatrutide 8 mg (-20.70 % and - 15.90 cm), and tirzepatide 15 mg (-16.53 % and - 13.23 cm) were the three most efficacious treatments for reducing body weight and waist circumference. However, these treatments were less effective in patients with type 2 diabetes mellitus (T2DM). In addition, patients with a high body mass index (BMI) or longer treatment cycles exhibited significantly greater weight loss than those with a low BMI or shorter treatment cycles. In terms of safety, patients without T2DM had a higher incidence of adverse events than those with T2DM. None of the interventions increased the incidence of serious adverse or hypoglycemic events (˂54 mg/dL). There was no significant difference in the incidence of adverse event withdrawal for all interventions in head-to-head comparisons. In addition, disparities in race, BMI, and treatment cycles did not significantly increase the incidence of adverse events. Finally, the sensitivity and publication bias analyses indicated that the basic analysis results were reliable.

CONCLUSION

Retatrutide (both doses) and tirzepatide exhibited superior efficacy compared to other GLP-1 receptor agonists and polyagonists in reducing body weight and waist circumference. Patients without T2DM, those with a high BMI, and individuals undergoing longer treatment cycles demonstrated significantly greater weight loss and reductions in waist circumference. Dual or triple receptor agonists (GLP-1 plus glucose-dependent insulinotropic polypeptide and/or Glucagon receptor) are more effective for weight loss than GLP-1 receptor agonists.

Effects of once-weekly subcutaneous retatrutide on weight and metabolic markers: A systematic review and meta-analysis of randomized controlled trials

Aim

To assess the effects of once-weekly subcutaneous retatrutide on weight and metabolic markers and the occurrence of side effects in patients with overweight, obesity and/or type 2 diabetes (T2D).

Methods

PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were systematically searched for placebo-controlled, randomized clinical trials (RCTs) published up until February 23, 2024. Weighted mean differences (WMDs) for continuous outcomes and risk ratios (RRs) for binary endpoints were computed, with 95 % confidence intervals (CIs).

Results

A total of three studies were included, comprising 640 patients, of whom 510 were prescribed retatrutide. Compared with placebo, retatrutide significantly reduced body weight (WMD -10.66 kg; 95 % CI -17.63, -3.69), body mass index (WMD -4.53 kg/m2; 95 % CI -7.51, -1.55), and waist circumference (WMD -6.61 cm; 95 % CI -13.17, -0.05). In addition, retatrutide significantly increased the proportion of patients who achieved a weight reduction of ≥5 % (RR 2.92; 95 % CI 2.17-3.93), ≥10 % (RR 9.32; 95 % CI 4.56-19.06), ≥15 % (RR 18.40; 95 % CI 6.00-56.42), and ≥20 % (RR 16.61; 95 % CI 4.17-66.12).

Conclusions

In this meta-analysis, the use of once-weekly subcutaneous retatrutide was associated with a significant reduction in body weight and improvement of metabolic markers in patients with overweight, obesity and/or T2D, compared with placebo, with an increase in non-severe gastrointestinal and hypersensitivity adverse events. Phase 3 RCTs are expected to shed further light on the efficacy and safety of once-weekly subcutaneous retatrutide over the long term.

Recent achievements and future directions of anti-obesity medications

Pharmacological management of obesity long suffered from a reputation of a 'Mission Impossible,' with inefficient weight loss and/or unacceptable tolerability. However, the tide has turned with recent progress in biochemical engineering and the development of long-acting agonists at the receptor for glucagon-like peptide-1 (GLP-1), and with unimolecular peptides that simultaneously possess activity at the receptors for GLP-1, the glucose-dependent insulinotropic polypeptide (GIP) and glucagon. Some of these novel therapeutics not only improve body weight and glycemic control in individuals with obesity and type 2 diabetes with hitherto unmet efficacy and tolerable safety, but also exhibit potential therapeutic value in diverse areas such as neurodegenerative diseases, fatty liver disease, dyslipidemia, atherosclerosis, and cardiovascular diseases. In this review, we highlight recent advances in incretin-based therapies and discuss their pharmacological potential within and beyond the treatment of obesity and diabetes, as well as their limitations in use, side effects, and underlying molecular mechanisms.

Variable glucagon metabolic actions in diverse mouse models of obesity and type 2 diabetes

OBJECTIVE

The study aimed to investigate the effects of glucagon on metabolic pathways in mouse models of obesity, fatty liver disease, and type 2 diabetes (T2D) to determine the extent and variability of hepatic glucagon resistance in these conditions.

METHODS

We investigated glucagon's effects in mouse models of fatty liver disease, obesity, and type 2 diabetes (T2D), including male BKS-db/db, high-fat diet-fed, and western diet-fed C57Bl/6 mice. Glucagon tolerance tests were performed using the selective glucagon receptor agonist acyl-glucagon (IUB288). Blood glucose, serum and liver metabolites include lipids and amino acids were measured. Additionally, liver protein expression related to glucagon signalling and a comprehensive liver metabolomics were performed.

RESULTS

Western diet-fed mice displayed impaired glucagon response, with reduced blood glucose and PKA activation. In contrast, high-fat diet-fed and db/db mice maintained normal glucagon sensitivity, showing significant elevations in blood glucose and phospho-PKA motif protein expression. Acyl-glucagon treatment also lowered liver alanine and histidine levels in high-fat diet-fed mice, but not in western diet-fed mice. Additionally, some amino acids, such as methionine, were increased by acyl-glucagon only in chow diet control mice. Despite normal glucagon sensitivity in PKA signalling, db/db mice had a distinct metabolomic response, with acyl-glucagon significantly altering 90 metabolites in db/+ mice but only 42 in db/db mice, and classic glucagon-regulated metabolites, such as cyclic adenosine monophosphate (cAMP), being less responsive in db/db mice.

CONCLUSIONS

The study reveals that hepatic glucagon resistance in obesity and T2D is complex and not uniform across metabolic pathways, underscoring the complexity of glucagon action in these conditions.

The impact of weight loss on fat-free mass, muscle, bone and hematopoiesis health: Implications for emerging pharmacotherapies aiming at fat reduction and lean mass preservation

Similar to bariatric surgery, incretin receptor agonists have revolutionized the treatment of obesity, achieving up to 15-25 % weight loss in many patients, i.e., at a rate approaching that achieved with bariatric surgery. However, over 25 % of total weight lost from both surgery and pharmacotherapy typically comes from fat-free mass, including skeletal muscle mass, which is often overlooked and can impair metabolic health and increase the risk of subsequent sarcopenic obesity. Loss of muscle and bone as well as anemia can compromise physical function, metabolic rate, and overall health, especially in older adults. The myostatin-activin-follistatin-inhibin system, originally implicated in reproductive function and subsequently muscle regulation, appears to be crucial for muscle and bone maintenance during weight loss. Activins and myostatin promote muscle degradation, while follistatins inhibit their activity in states of negative energy balance, thereby preserving lean mass. Novel compounds in the pipeline, such as Bimagrumab, Trevogrumab, and Garetosmab-which inhibit activin and myostatin signaling-have demonstrated promise in preventing muscle loss while promoting fat loss. Either alone or combined with incretin receptor agonists, these medications may enhance fat loss while preserving or even increasing muscle and bone mass, offering a potential solution for improving body composition and metabolic health during significant weight loss. Since this dual therapeutic approach could help address the challenges of muscle and bone loss during weight loss, well-designed studies are needed to optimize these strategies and assess long-term benefits. For the time being, considerations like advanced age and prefrailty may affect the choice of suitable candidates in clinical practice for current and emerging anti-obesity medications due to the associated risk of sarcopenia.

Comparative Effects of GLP-1 Agonists, Sleeve Gastrectomy and Roux-en-Y Gastric Bypass on Diabetes Mellitus Outcomes

PURPOSE OF REVIEW

The purpose of this review is to assess the effects of glucagon-like peptide-1 (GLP-1) agonists, sleeve gastrectomy (SG), and Roux-en-Y gastric bypass (RYGB) on type 2 diabetes mellitus (T2DM) remission. This review explores the efficacy, safety, and durability of these surgical and medical modalities of diabetes management.

RECENT FINDINGS

Studies have shown that GLP-1 agonists achieve higher rates of T2DM remission compared to standard glucose-lowering medications and lifestyle changes. In addition to weight loss, bariatric surgery has been found to be highly effective in treating and inducing remission of T2DM. Studies suggest that post-surgical patients see enhanced glycemic control. Both surgical interventions and GLP1 agonists are effective in achieving T2DM remission. Long-term follow-up and randomized controlled trials comparing bariatric surgery and GLP-1 agonists are necessary to evaluate their relative effectiveness in T2DM control. Further research is also needed to assess the combined effects of these treatment modalities.