Separate and combined effects of empagliflozin and semaglutide on vascular function: A 32-week randomized trial

GLP-1 Receptor Agonists and SGLT2 Inhibitors in Type 2 Diabetes: Pleiotropic Cardiometabolic Effects and Add-on Value of a Combined Therapy

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2is) have proven efficacy and safety in randomized clinical trials and observational real-life studies. Besides improving glucose control, reducing body weight, and lowering arterial blood pressure (surrogate endpoints), the breakthroughs were the demonstration of a significant reduction in cardiovascular and renal events in patients with type 2 diabetes at high risk. GLP-1RAs reduce events linked to atherogenic cardiovascular disease (especially ischemic stroke) and also renal outcomes (FLOW trial with semaglutide), with a limited effect on heart failure. The most striking protective effects of SGLT2is were a marked reduction in hospitalization for heart failure and a remarkable reduced progression of chronic kidney disease. These benefits have been attributed to numerous pleiotropic effects beyond glucose-lowering action. Underlying mechanisms contributing to cardiovascular and renal protection are at least partially different between GLP-1RAs (mainly anti-atherogenic and vascular effects) and SGLT2is (mainly systemic and intrarenal hemodynamic changes). Thus, patients at high risk may benefit from complementary actions when being treated with a GLP-1RA/SGLT2i combination. Such combination has proven its efficacy on surrogate endpoints. Furthermore, post hoc subgroup analyses of cardiovascular outcome trials have suggested a greater cardiorenal protection in patients treated with a combination versus either monotherapy. The benefits of a combined therapy have been confirmed in a few retrospective cohort studies. A dedicated prospective trial comparing a combined therapy versus either monotherapy is ongoing (PRECIDENTD); however, several challenges still remain, especially the higher cost of a combined therapy and the worldwide underuse of either GLP-1RAs or SGLT2is in clinical practice, even in patients at high cardiorenal risk.

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.

Effects of semaglutide with and without concomitant SGLT2 inhibitor use in participants with type 2 diabetes and chronic kidney disease in the FLOW trial

People with type 2 diabetes and chronic kidney disease have a high risk for kidney failure and cardiovascular (CV) complications. Glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors (SGLT2i) independently reduce CV and kidney events. The effect of combining both is unclear. FLOW trial participants with type 2 diabetes and chronic kidney disease were stratified by baseline SGLT2i use (N = 550) or no use (N = 2,983) and randomized to semaglutide/placebo. The primary outcome was a composite of kidney failure, ≥50% estimated glomerular filtration rate reduction, kidney death or CV death. The risk of the primary outcome was 24% lower in all participants treated with semaglutide versus placebo (95% confidence interval: 34%, 12%). The primary outcome occurred in 41/277 (semaglutide) versus 38/273 (placebo) participants on SGLT2i at baseline (hazard ratio 1.07; 95% confidence interval: 0.69, 1.67; P = 0.755) and in 290/1,490 versus 372/1,493 participants not taking SGLT2i at baseline (hazard ratio 0.73; 0.63, 0.85; P < 0.001; P interaction 0.109). Three confirmatory secondary outcomes were predefined. Treatment differences favoring semaglutide for total estimated glomerular filtration rate slope (ml min-1/1.73 m2/year) were 0.75 (-0.01, 1.5) in the SGLT2i subgroup and 1.25 (0.91, 1.58) in the non-SGLT2i subgroup, P interaction 0.237. Semaglutide benefits on major CV events and all-cause death were similar regardless of SGLT2i use (P interaction 0.741 and 0.901, respectively). The benefits of semaglutide in reducing kidney outcomes were consistent in participants with/without baseline SGLT2i use; power was limited to detect smaller but clinically relevant effects. ClinicalTrials.gov identifier: NCT03819153 .

Efficacy and safety of SGLT2 inhibitors with and without glucagon-like peptide 1 receptor agonists: a SMART-C collaborative meta-analysis of randomised controlled trials

BACKGROUND

SGLT2 inhibitors and GLP-1 receptor agonists both improve cardiovascular and kidney outcomes in patients with type 2 diabetes. We sought to evaluate whether the benefits of SGLT2 inhibitors are consistent in patients receiving and not receiving GLP-1 receptor agonists.

METHODS

We conducted a collaborative meta-analysis of trials included in the SGLT2 Inhibitor Meta-Analysis Cardio-Renal Trialists' Consortium, restricted to participants with diabetes. Treatment effects from individual trials were obtained from Cox regression models and pooled using inverse variance weighted meta-analysis. The two main cardiovascular outcomes assessed included major adverse cardiovascular events (nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death), and hospitalisation for heart failure or cardiovascular death. The main kidney outcomes assessed were chronic kidney disease progression (≥40% decline in estimated glomerular filtration rate [eGFR], kidney failure [eGFR <15 mL/min/1·73 m2, chronic dialysis, or kidney transplantation], or death due to kidney failure), and the rate of change in eGFR over time. Safety outcomes were also assessed.

FINDINGS

Across 12 randomised, double-blind, placebo-controlled trials, 3065 (4·2%) of 73 238 participants with diabetes were using GLP-1 receptor agonists at baseline. SGLT2 inhibitors reduced the risk of major adverse cardiovascular events in participants both receiving and not receiving GLP-1 receptor agonists (hazard ratio [HR] 0·81, 95% CI 0·63-1·03 vs 0·90, 0·86-0·94; p-heterogeneity=0·31). Effects on hospitalisation for heart failure or cardiovascular death (0·76, 0·57-1·01 vs 0·78, 0·74-0·82; p-heterogeneity=0·90) and chronic kidney disease progression (0·65, 0·46-0·94 vs 0·67, 0·62-0·72; p-heterogeneity=0·81) were also consistent regardless of GLP-1 receptor agonist use, as was the effect on the chronic rate of change in eGFR over time (heterogeneity=0·92). Fewer serious adverse events occurred with SGLT2 inhibitors compared with placebo, irrespective of GLP-1 receptor agonist use (relative risk 0·87, 95% CI 0·79-0·96 vs 0·91, 0·89-0·93; p-heterogeneity=0·41).

INTERPRETATION

The effects of SGLT2 inhibitors on cardiovascular and kidney outcomes are consistent regardless of the background use of GLP-1 receptor agonists. These findings suggest independent effects of these evidence-based therapies and support clinical practice guidelines recommending the use of these agents in combination to improve cardiovascular and kidney metabolic outcomes.

FUNDING

National Health and Medical Research Council of Australia and the Ramaciotti Foundation.

The effect of SGLT2 inhibitors and GLP1 receptor agonists on arterial stiffness: A meta-analysis of randomized controlled trials

BACKGROUND

Pulse wave velocity (PWV) and augmentation index (AIx) are indices used to assess arterial stiffness. We evaluated the effect of sodium glucose co-transporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP1-RA) on arterial stiffness indices.

METHODS

We searched PubMed (up to January 2024) for RCTs assessing the effect of SGLT2i or GLP1-RA on arterial stiffness with reporting outcomes PWV and AIx. Effect sizes of the included studies were expressed as weighted mean difference (WMD) and 95 % confidence interval. Subgroup analyses were performed based on comparator (placebo vs. active comparator), design (RCT vs. crossover), population (diabetic vs. all) and blindness (yes vs. no).

RESULTS

A total of 19 studies (SGLT2i, 12 studies; GLP1-RA, 5 studies; SGLT2i/GLP1-RA combination, 2 studies) assessing 1212 participants were included. We did not find any statistically significant association between GLP1-RA or SGLT2i and PWV or AIx. None of the subgroup analyses showed any statistically significant result.

CONCLUSION

No evidence of a favorable change in arterial stiffness indices (PWV, AIx) was found following the administration of SGLT2i or GLP1-RA.

Effect of Semaglutide and Empagliflozin on Pulmonary Structure and Proteomics in Obese Mice

Objective

This study utilized proteomics to investigate changes in protein expression associated with lung health in obese mice exposed to semaglutide and empagliflozin through a high-fat diet.

Methods

Twenty-eight male C57BL/6JC mice were randomly assigned to two groups: a control diet group (n = 7) and a high-fat diet group (n = 21). The HFD group was further divided into three groups: HFD group (n = 7), Sema group (n = 7), and Empa group (n = 7). Post-treatment, mice underwent assessments including glucose tolerance, lipids, oxidative stress markers, body weight, lung weight, and structure. Proteomics identified differentially expressed proteins (DEPs) in lung tissue, and bioinformatics analyzed the biological processes and functions of these proteins.

Results

Semaglutide and empagliflozin significantly attenuated obesity-induced hyperglycemia, abnormal lipid metabolism, oxidative stress response, and can decrease alveolar wall thickness, enlarge alveolar lumen, and reduce collagen content in lung tissue. Both medications also attenuated lung elastic fibre cracking and disintegration. In the HFD/NCD group, there were 66 DEPs, comprising 30 proteins that were increased and 36 that were decreased. Twenty-three DEPs overlapped between Sema/HFD and Empa/HFD, with 11 up-regulated and 12 down-regulated simultaneously. After analysing DEPs in different groups, four proteins - LYVE1, BRAF, RGCC, and CHMP5 - were all downregulated in the HFD group and upregulated by semaglutide and empagliflozin treatment.

Conclusion

This study demonstrates that obesity induced by a high-fat diet causes a reduction in the expression of LYVE1, BRAF, RGCC, and CHMP5 proteins, potentially affecting lung function and structure in mice. Significantly, the administration of semaglutide and empagliflozin elevates the levels of these proteins, potentially offering therapeutic benefits against lung injury caused by obesity. Merging semaglutide with empagliflozin may exert a more pronounced impact.