The potential of GLP-1 receptor agonists in type 2 diabetes and chronic kidney disease: from randomised trials to clinical practice

The role of glucagon-like peptide-1/GLP-1R and autophagy in diabetic cardiovascular disease

Diabetes leads to a significantly accelerated incidence of various related macrovascular complications, including peripheral vascular disease and cardiovascular disease (the most common cause of mortality in diabetes), as well as microvascular complications such as kidney disease and retinopathy. Endothelial dysfunction is the main pathogenic event of diabetes-related vascular disease at the earliest stage of vascular injury. Understanding the molecular processes involved in the development of diabetes and its debilitating vascular complications might bring up more effective and specific clinical therapies. Long-acting glucagon-like peptide (GLP)-1 analogs are currently available in treating diabetes with widely established safety and extensively evaluated efficacy. In recent years, autophagy, as a critical lysosome-dependent self-degradative process to maintain homeostasis, has been shown to be involved in the vascular endothelium damage in diabetes. In this review, the GLP-1/GLP-1R system implicated in diabetic endothelial dysfunction and related autophagy mechanism underlying the pathogenesis of diabetic vascular complications are briefly presented. This review also highlights a possible crosstalk between autophagy and the GLP-1/GLP-1R axis in the treatment of diabetic angiopathy.

Effects of semaglutide, empagliflozin and their combination on renal diffusion-weighted MRI and total kidney volume in patients with type 2 diabetes: a post hoc analysis from a 32 week randomised trial

AIMS/HYPOTHESIS

The apparent diffusion coefficient (ADC) derived from diffusion-weighted MRI (DWI-MRI) has been proposed as a measure of changes in kidney microstructure, including kidney fibrosis. In advanced kidney disease, the kidneys often become atrophic; however, in the initial phase of type 2 diabetes, there is an increase in renal size. Glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors both provide protection against progression of kidney disease in diabetes. However, the mechanisms are incompletely understood. To explore this, we examined the effects of semaglutide, empagliflozin and their combination on renal ADC and total kidney volume (TKV).

METHODS

This was a substudy of a randomised clinical trial on the effects of semaglutide and empagliflozin alone or in combination. Eighty patients with type 2 diabetes and high risk of CVD were randomised into four groups (n=20 in each) receiving either tablet placebo, empagliflozin, a combination of semaglutide and tablet placebo (herein referred to as the 'semaglutide' group), or the combination of semaglutide and empagliflozin (referred to as the 'combination-therapy' group). The semaglutide and the combination-therapy group had semaglutide treatment for 16 weeks and then had either tablet placebo or empagliflozin added to the treatment, respectively, for a further 16 weeks; the placebo and empagliflozin groups were treated with the respective monotherapy for 32 weeks. We analysed the effects of treatment on changes in ADC (cortical, medullary and the cortico-medullary difference [ΔADC; medullary ADC subtracted from cortical ADC]), as well as TKV measured by MRI.

RESULTS

Both semaglutide and empagliflozin decreased cortical ADC significantly compared with placebo (semaglutide: -0.20×10-3 mm2/s [95% CI -0.30, -0.10], p<0.001; empagliflozin: -0.15×10-3 mm2/s [95% CI -0.26, -0.04], p=0.01). No significant change was observed in the combination-therapy group (-0.05×10-3 mm2/s [95%CI -0.15, 0.05]; p=0.29 vs placebo). The changes in cortical ADC were not associated with changes in GFR, albuminuria, TKV or markers of inflammation. Further, there were no changes in medullary ADC in any of the groups compared with placebo. Only treatment with semaglutide changed ΔADC significantly from placebo, showing a decrease of -0.13×10-3 mm2/s (95% CI -0.22, -0.04; p=0.01). Compared with placebo, TKV decreased by -3% (95% CI -5%, -0.3%; p=0.04), -3% (95% CI -5%, -0.4%; p=0.02) and -5% (95% CI -8%, -2%; p<0.001) in the semaglutide, empagliflozin and combination-therapy group, respectively. The changes in TKV were associated with changes in GFR, albuminuria and HbA1c.

CONCLUSIONS/INTERPRETATION

In a population with type 2 diabetes and high risk of CVD, semaglutide and empagliflozin significantly reduced cortical ADC compared with placebo, indicating microstructural changes in the kidneys. These changes were not associated with changes in GFR, albuminuria or inflammation. Further, we found a decrease in TKV in all active treatment groups, which was possibly mediated by a reduction in hyperfiltration. Our findings suggest that DWI-MRI may serve as a promising tool for investigating the underlying mechanisms of medical interventions in individuals with type 2 diabetes but may reflect effects not related to fibrosis.

TRIAL REGISTRATION

European Union Drug Regulating Authorities Clinical Trials Database (EudraCT) 2019-000781-38.

Underuse of GLP-1 receptor agonists in the management of type 2 diabetes despite a favorable benefit-safety profile

INTRODUCTION

Patients with type 2 diabetes (T2DM) are at high risk of atherosclerotic cardiovascular disease (ASCVD) and cardiovascular death. Cardiovascular protection is a key objective in T2DM.

AREAS COVERED

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have proven their efficacy in reducing major cardiovascular events in high-risk patients with T2DM in placebo-controlled trials, a finding confirmed in observational studies compared with other glucose-lowering agents. Overall, GLP-1RAs have a good safety profile associated with a favorable benefit/risk ratio for the management of T2DM, even if their cost-effectiveness might be questionable. International guidelines recommend GLP-1RAs as preferred glucose-lowering agents in patients with ASCVD and as a valuable alternative in overweight/obese patients with T2DM. However, real-life studies worldwide revealed that only a minority of patients receive a GLP-1RA, despite a positive trend for increased prescriptions in recent years. Surprisingly, however, fewer patients with established ASCVD are treated with these cardioprotective antihyperglycemic agents versus patients without ASCVD.

EXPERT OPINION

The reasons for GLP-1RA underuse in clinical practice are multiple. Multifaceted and coordinated interventions targeting all actors of the health-care system must be implemented to stimulate the adoption of GLP-1RAs as part of routine cardiovascular care among patients with T2DM, especially in those with ASCVD.

Metabolic Analysis and Renal Protective Effects of Linagliptin and Empagliflozin in Alport Syndrome

Key Points

Linagliptin reduces kidney function decline and extends lifespan in Alport syndrome mice. Inhibiting the generation of glucose metabolites could serve as a potential therapeutic strategy for the treatment of Alport syndrome.

Background

We previously demonstrated that empagliflozin (Empa), a sodium-glucose cotransporter-2 inhibitor, reduces intrarenal lipid accumulation and slows kidney function decline in experimental Alport syndrome (AS). In this study, we aimed to evaluate the renal protective benefits of linagliptin (Lina), a dipeptidyl peptidase-4 inhibitor in AS, and compare it with Empa.

Methods

Metabolite distribution in kidney cortices was assessed using mass spectrometry imaging. We examined albuminuria and histological changes in kidneys from AS mice treated with Lina and/or Empa or vehicle.

Results

Several metabolites, including adrenic acid and glucose, were increased in renal cortices of AS mice compared with wild-type (WT) mice, whereas eicosapentaenoic acid levels were decreased. In addition, a redistribution of adrenic acid from the glomerular compartment in WT mice to the tubulointerstitial compartment in AS mice was observed. Both Lina and Empa treatments were found to reduce albuminuria to extend the survival of AS mice for about 10 days and to decrease glomerulosclerosis and tubulointerstitial fibrosis compared with WT mice. There were no significant differences with regard to the renal phenotype observed between Empa- and Lina-treated AS mice, and the combination of Lina and Empa was not superior to individual treatments. In vitro experiments revealed that dipeptidyl peptidase-4 is expressed in podocytes and tubular cells derived from both AS and WT mice. Differently from what we have reported for Empa, Lina treatment was found to reduce glucose-driven respiration in AS tubular cells but not in AS podocytes.

Conclusions

Renal expression patterns and spatial distribution of several metabolites differ in AS compared with WT mice. Although Lina and Empa treatments similarly partially slow the progression of kidney disease in AS, the metabolic mechanisms conferring the protective effect may be different.

Strategies to address diabetic kidney disease burden in Mexico: a narrative review by the Mexican College of Nephrologists

Chronic kidney disease (CKD) is a growing global public health challenge worldwide. In Mexico, CKD prevalence is alarmingly high and remains a leading cause of morbidity and mortality. Diabetic kidney disease (DKD), a severe complication of diabetes, is a leading determinant of CKD. The escalating diabetes prevalence and the complex regional landscape in Mexico underscore the pressing need for tailored strategies to reduce the burden of CKD. This narrative review, endorsed by the Mexican College of Nephrologists, aims to provide a brief overview and specific strategies for healthcare providers regarding preventing, screening, and treating CKD in patients living with diabetes in all care settings. The key topics covered in this review include the main cardiometabolic contributors of DKD (overweight/obesity, hyperglycemia, arterial hypertension, and dyslipidemia), the identification of kidney-related damage markers, and the benefit of novel pharmacological approaches based on Sodium-Glucose Co-Transporter-2 Inhibitors (SGLT2i) and Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RA). We also address the potential use of novel therapies based on Mineralocorticoid Receptor Antagonists (MRAs) and their future implications. Emphasizing the importance of multidisciplinary treatment, this narrative review aims to promote strategies that may be useful to alleviate the burden of DKD and its associated complications. It underscores the critical role of healthcare providers and advocates for collaborative efforts to enhance the quality of life for millions of patients affected by DKD.

CVOT Summit Report 2023: new cardiovascular, kidney, and metabolic outcomes

The 9th Cardiovascular Outcome Trial (CVOT) Summit: Congress on Cardiovascular, Kidney, and Metabolic Outcomes was held virtually on November 30-December 1, 2023. This reference congress served as a platform for in-depth discussions and exchange on recently completed outcomes trials including dapagliflozin (DAPA-MI), semaglutide (SELECT and STEP-HFpEF) and bempedoic acid (CLEAR Outcomes), and the advances they represent in reducing the risk of major adverse cardiovascular events (MACE), improving metabolic outcomes, and treating obesity-related heart failure with preserved ejection fraction (HFpEF). A broad audience of endocrinologists, diabetologists, cardiologists, nephrologists and primary care physicians participated in online discussions on guideline updates for the management of cardiovascular disease (CVD) in diabetes, heart failure (HF) and chronic kidney disease (CKD); advances in the management of type 1 diabetes (T1D) and its comorbidities; advances in the management of CKD with SGLT2 inhibitors and non-steroidal mineralocorticoid receptor antagonists (nsMRAs); and advances in the treatment of obesity with GLP-1 and dual GIP/GLP-1 receptor agonists. The association of diabetes and obesity with nonalcoholic steatohepatitis (NASH; metabolic dysfunction-associated steatohepatitis, MASH) and cancer and possible treatments for these complications were also explored. It is generally assumed that treatment of chronic diseases is equally effective for all patients. However, as discussed at the Summit, this assumption may not be true. Therefore, it is important to enroll patients from diverse racial and ethnic groups in clinical trials and to analyze patient-reported outcomes to assess treatment efficacy, and to develop innovative approaches to tailor medications to those who benefit most with minimal side effects. Other keys to a successful management of diabetes and comorbidities, including dementia, entail the use of continuous glucose monitoring (CGM) technology and the implementation of appropriate patient-physician communication strategies. The 10th Cardiovascular Outcome Trial Summit will be held virtually on December 5-6, 2024 ( http://www.cvot.org ).

Comparison of GLP-1 receptor agonists and other Glucose-Lowering agents on cardiovascular outcomes in individuals with type 2 diabetes and Obesity: A Spanish Real-World Population-Based study

AIMS

Assess the impact of glucagon-like peptide receptor agonists (GLP-1RA) compared to other glucose-lowering agents on cardiovascular outcomes in individuals with type 2 diabetes and obesity in a Spanish metropolitan area.

METHODS

A retrospective population-based type 2 diabetes cohort was identified from the Valencia Clinic-Malvarrosa Department electronic databases (2014-2019). Study groups included GLP-1RA, sodium-glucose co-transporter-2 inhibitors (SGLT2i), Insulin, and Miscellany (other glucose-lowering agents). 1:1:1:1 propensity score matching was conducted. The primary outcome was a composite of major adverse cardiovascular events (4-point MACE) comprising myocardial infarction, stroke, all-cause mortality, and heart failure. Secondary outcomes included individual 4-point MACE components. Hazard ratios were estimated using Cox regression analyses against the Miscellany group.

RESULTS

From 26,944 subjects, 1,848 adults were selected per group. GLP-1RA did not show a significant reduction in 4-point MACE risk (HR 1.05 [95%CI 0.82-1.34]). SGLT2i significantly reduced the risk of heart failure (HR 0.16 [95%CI 0.05-0.54]) and atrial fibrillation (HR 0.58, [95%CI 0.35-0.95]). The Insulin group exhibited a higher risk for 4-point MACE and most individual outcomes compared to GLP-1RA and SGLT2i.

CONCLUSIONS

Our findings do not provide evidence of a reduced cardiovascular risk, as assessed by 4-point MACE, with GLP-1RA. In contrast, SGLT2i demonstrated protective effects against heart failure and atrial fibrillation.

Effect of semaglutide on major adverse cardiovascular events by baseline kidney parameters in participants with type 2 diabetes and at high risk of cardiovascular disease: SUSTAIN 6 and PIONEER 6 post hoc pooled analysis

BACKGROUND

Semaglutide is a glucose-lowering treatment for type 2 diabetes (T2D) with demonstrated cardiovascular benefits; semaglutide may also have kidney-protective effects. This post hoc analysis investigated the association between major adverse cardiovascular events (MACE) and baseline kidney parameters and whether the effect of semaglutide on MACE risk was impacted by baseline kidney parameters in people with T2D at high cardiovascular risk.

METHODS

Participants from the SUSTAIN 6 and PIONEER 6 trials, receiving semaglutide or placebo, were categorised according to baseline kidney function (estimated glomerular filtration rate [eGFR] < 45 and ≥ 45-<60 versus ≥ 60 mL/min/1.73 m2) or damage (urine albumin:creatinine ratio [UACR] ≥ 30-≤300 and > 300 versus < 30 mg/g). Relative risk of first MACE by baseline kidney parameters was evaluated using a Cox proportional hazards model. The same model, adjusted with inverse probability weighting, and a quadratic spline regression were applied to evaluate the effect of semaglutide on risk and event rate of first MACE across subgroups. The semaglutide effects on glycated haemoglobin (HbA1c), body weight (BW) and serious adverse events (SAEs) across subgroups were also evaluated.

RESULTS

Independently of treatment, participants with reduced kidney function (eGFR ≥ 45-<60 and < 45 mL/min/1.73 m2: hazard ratio [95% confidence interval]; 1.36 [1.04;1.76] and 1.52 [1.15;1.99]) and increased albuminuria (UACR ≥ 30-≤300 and > 300 mg/g: 1.53 [1.14;2.04] and 2.52 [1.84;3.42]) had an increased MACE risk versus those without. Semaglutide consistently reduced MACE risk versus placebo across all eGFR and UACR subgroups (interaction p value [pINT] > 0.05). Semaglutide reduced HbA1c regardless of baseline eGFR and UACR (pINT>0.05); reductions in BW were affected by baseline eGFR (pINT<0.001) but not UACR (pINT>0.05). More participants in the lower eGFR or higher UACR subgroups experienced SAEs versus participants in reference groups; the number of SAEs was similar between semaglutide and placebo arms in each subgroup.

CONCLUSIONS

MACE risk was greater for participants with kidney impairment or damage than for those without. Semaglutide consistently reduced MACE risk across eGFR and UACR subgroups, indicating that semaglutide provides cardiovascular benefits in people with T2D and at high cardiovascular risk across a broad spectrum of kidney function and damage.

TRIAL REGISTRATIONS

NCT01720446; NCT02692716.

Glucagon-like peptide-1 receptor agonists to expand the healthy lifespan: Current and future potentials

To help ensure an expanded healthy lifespan for as many people as possible worldwide, there is a need to prevent or manage a number of prevalent chronic diseases directly and indirectly closely related to aging, including diabetes and obesity. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) have proven beneficial in type 2 diabetes, are amongst the few medicines approved for weight management, and are also licensed for focused cardiovascular risk reduction. In addition, strong evidence suggests several other beneficial effects of the pleiotropic peptide hormone, including anti-inflammation. Consequently, GLP-1 RAs are now in advanced clinical development for the treatment of chronic kidney disease, broader cardiovascular risk reduction, metabolic liver disease and Alzheimer's disease. In sum, GLP-1 RAs are positioned as one of the pharmacotherapeutic options that can contribute to addressing the high unmet medical need characterising several prevalent aging-related diseases, potentially helping more people enjoy a prolonged healthy lifespan.

CVOT Summit 2022 Report: new cardiovascular, kidney, and glycemic outcomes

The 8th Cardiovascular Outcome Trial (CVOT) Summit on Cardiovascular, Kidney, and Glycemic Outcomes was held virtually on November 10-12, 2022. Following the tradition of previous summits, this reference congress served as a platform for in-depth discussion and exchange on recently completed outcomes trials as well as key trials important to the cardiovascular (CV) field. This year's focus was on the results of the DELIVER, EMPA-KIDNEY and SURMOUNT-1 trials and their implications for the treatment of heart failure (HF) and chronic kidney disease (CKD) with sodium-glucose cotransporter-2 (SGLT2) inhibitors and obesity with glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonists. A broad audience of primary care physicians, diabetologists, endocrinologists, cardiologists, and nephrologists participated online in discussions on new consensus recommendations and guideline updates on type 2 diabetes (T2D) and CKD management, overcoming clinical inertia, glycemic markers, continuous glucose monitoring (CGM), novel insulin preparations, combination therapy, and reclassification of T2D. The impact of cardiovascular outcomes on the design of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) trials, as well as the impact of real-world evidence (RWE) studies on the confirmation of CVOT outcomes and clinical trial design, were also intensively discussed. The 9th Cardiovascular Outcome Trial Summit will be held virtually on November 23-24, 2023 ( http://www.cvot.org ).

Finerenone in patients across the spectrum of chronic kidney disease and type 2 diabetes by glucagon-like peptide-1 receptor agonist use

AIMS

To explore the modifying effect of glucagon-like peptide-1 receptor agonist (GLP-1RA) use on outcomes with finerenone across a wide spectrum of patients with chronic kidney disease (CKD) and type 2 diabetes (T2D) in the pooled analysis of FIDELIO-DKD and FIGARO-DKD.

MATERIALS AND METHODS

Patients with T2D and CKD treated with optimized renin-angiotensin system blockade were randomized to finerenone or placebo. Effects of finerenone on a cardiovascular composite outcome (cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure) and a kidney composite outcome (kidney failure, sustained ≥57% estimated glomerular filtration rate [eGFR] decline, or renal death), change in urine albumin-to-creatinine ratio (UACR), and safety were analysed by GLP-1RA use.

RESULTS

Of 13 026 patients, 944 (7.2%) used GLP-1RAs at baseline. Finerenone reduced the risk of the cardiovascular composite outcome (hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.52-1.11 with GLP-1RA; HR 0.87, 95% CI 0.79-0.96 without GLP-1RA; P-interaction = 0.63) and the kidney composite outcome (HR 0.82, 95% CI 0.45-1.48 with GLP-1RA; HR 0.77, 95% CI 0.67-0.89 without GLP-1RA; P-interaction = 0.79) irrespective of baseline GLP-1RA use. Reduction in UACR with finerenone at Month 4 was -38% in patients with baseline GLP-1RA use compared with -31% in those without GLP-1RA use (P-interaction = 0.03). Overall safety and incidence of hyperkalaemia were similar, irrespective of GLP-1RA use.

CONCLUSIONS

The cardiorenal benefits of finerenone on composite cardiovascular and kidney outcomes and UACR reduction in patients with CKD and T2D appear to be maintained, regardless of GLP-1RA use. Subsequent studies are needed to investigate any potential benefit of this combination.

Nonalcoholic Fatty Liver Disease and Chronic Kidney Disease: Epidemiology, Pathogenesis, and Clinical and Research Implications

Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease worldwide, affecting up to ~30% of adult populations. NAFLD defines a spectrum of progressive liver conditions ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma, which often occur in close and bidirectional associations with metabolic disorders. Chronic kidney disease (CKD) is characterized by anatomic and/or functional renal damage, ultimately resulting in a reduced glomerular filtration rate. The physiological axis linking the liver and kidneys often passes unnoticed until clinically significant portal hypertension, as a major complication of cirrhosis, becomes apparent in the form of ascites, refractory ascites, or hepatorenal syndrome. However, the extensive evidence accumulated since 2008 indicates that noncirrhotic NAFLD is associated with a higher risk of incident CKD, independent of obesity, type 2 diabetes, and other common renal risk factors. In addition, subclinical portal hypertension has been demonstrated to occur in noncirrhotic NAFLD, with a potential adverse impact on renal vasoregulation. However, the mechanisms underlying this association remain unexplored to a substantial extent. With this background, in this review we discuss the current evidence showing a strong association between NAFLD and the risk of CKD, and the putative biological mechanisms underpinning this association. We also discuss in depth the potential pathogenic role of the hepatorenal reflex, which may be triggered by subclinical portal hypertension and is a poorly investigated but promising research topic. Finally, we address emerging pharmacotherapies for NAFLD that may also beneficially affect the risk of developing CKD in individuals with NAFLD.

The potential of glucagon-like peptide-1 receptor agonists in heart failure

Heart failure (HF) remains one of the cardiovascular diseases (CVDs) associated with a high unmet medical need due to high morbidity and mortality rates and lack of efficacious interventions. HF is closely related to cardiometabolic diseases such as diabetes, obesity and chronic kidney disease, and strategies that address most or all these intertwined conditions are desirable. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are approved for type 2 diabetes (T2D), and some are also indicated for reduction of the risk of atherosclerotic CVD in T2D and for weight management. As we summarise in this concise review, preliminary evidence suggests that the cardioprotective benefits of GLP-1 RAs may also extend to HF. The most robust clinical evidence arguably originates from the large cardiovascular outcomes trials (CVOTs) completed for most GLP-1 RAs, of which the latest showed a significant relative risk reduction (RRR) of 39% (HR) with once-weekly efpeglenatide on HF requiring hospitalisation, corroborating a meta-analysis which found a significant RRR across eight GLP-1 RA CVOTs of 11%. Further, although incompletely described, multiple studies are available to provide insights into the mechanistic underpinnings, which appear to be associated mostly with indirect cardioprotective benefits owing to the ability of GLP-1 RAs to address hyperglycaemia, and reduce body weight, and, amongst others, inflammation. In sum, current evidence positions GLP-1 RAs as a potential cardioprotective strategy in HF, with HF with preserved ejection fraction emerging as the clinically most relevant phenotype for the drug class, especially when occurring in people with obesity with and without diabetes.