A review of GLP-1 receptor agonists: Evolution and advancement, through the lens of randomised controlled trials

Optimizing expression, purification, structural and functional assessments of a novel dimeric incretin (GLP-1cpGLP-1)

Glucagon-like peptide-1 (GLP-1) is an incretin hormone that reduces postprandial glycemic excursions by enhancing insulin secretion. In this study, a new dimeric GLP-1 analogue (GLP-1cpGLP-1) was designed by inserting human insulin C-peptide (CP) in the middle of a dimer of [Gly8] GLP-1 (7-36). Then, the dimeric incretin (GLP-1cpGLP-1) was ligated to human αB-crystallin (αB-Cry) to create a hybrid protein, abbreviated as αB-GLP-1cpGLP-1. The constructed gene was well expressed in the bacterial host system. After specific chemical release from the hybrid protein, the dimeric incretin was purified by size exclusion chromatography (SEC). Finally, the RP-HPLC analysis indicated a purity of >99 % for the dimeric incretin. The secondary structure assessments by various spectroscopic methods, and in silico analysis suggested that the dimeric incretin has α-helical rich structure. The dynamic light scattering (DLS) analysis indicates that our dimeric incretin forms large oligomeric structures. This incretin analogue significantly reduced blood glucose levels in both healthy and diabetic mice while effectively triggering insulin release. The size exclusion HPLC also indicates the interaction of the new incretin analogue with human serum albumin, the main carrier protein in the bloodstream. Consistent with the results obtained from the biological activity assessments, this significant interaction indicates its potential as a viable therapeutic agent with a long-lasting effect. The results of our research represent a significant breakthrough in the successful design of an active incretin dimer capable of effectively controlling blood sugar levels and inducing insulin secretion in the realm of diabetes treatment.

Effect of pemvidutide, a GLP-1/glucagon dual receptor agonist, on MASLD: A randomized, double-blind, placebo-controlled study

BACKGROUND & AIMS

This was a randomized, double-blind, placebo-controlled study to assess the effects of pemvidutide, a glucagon-like peptide-1 (GLP-1)/glucagon dual receptor agonist, on liver fat content (LFC) in subjects with metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

Subjects with a BMI ≥28.0 kg/m2 and LFC ≥10% by magnetic resonance imaging-proton density fat fraction were randomized 1:1:1:1 to pemvidutide at 1.2 mg, 1.8 mg, or 2.4 mg, or placebo administered subcutaneously once weekly for 12 weeks. Participants were stratified according to a diagnosis of type 2 diabetes mellitus (T2DM). The primary efficacy endpoint was relative reduction (%) from baseline in LFC after 12 weeks of treatment.

RESULTS

94 subjects were randomized and dosed. Median baseline BMI and LFC across the study population were 36.2 kg/m2 and 20.6%; 29% of subjects had T2DM. At Week 12, relative reductions in LFC from baseline were (1.2 mg) 46.6% [95% CI -63.7 to -29.6], (1.8 mg) 68.5% [95% CI -84.4 to -52.5], and (2.4 mg) 57.1% [95% CI -76.1 to -38.1] versus 4.4% [95% CI -20.2 to 11.3] in placebo subjects (p <0.001 vs. placebo, all treatment groups), with 94.4% and 72.2% of subjects achieving 30% and 50% reductions in LFC and 55.6% achieving normalization (≤5% LFC) at the 1.8 mg dose. Maximal responses for weight loss (-4.3%; p <0.001), alanine aminotransferase (-13.8 IU/L; p = 0.029), and corrected cT1 (-75.9 ms; p = 0.002) were all observed at the 1.8 mg dose. Pemvidutide was well-tolerated at all doses with no severe or serious adverse events.

CONCLUSIONS

In subjects with MASLD, weekly pemvidutide treatment yielded significant reductions in LFC, markers of hepatic inflammation, and body weight compared to placebo.

IMPACT AND IMPLICATIONS

MASLD, and MASH, are strongly associated with overweight and obesity and it is believed that the excess liver fat associated with obesity is an important driver of these diseases. Glucagon-like peptide-1 receptor (GLP-1R) agonists elicit weight loss through centrally and peripherally mediated effects on appetite. Unlike GLP-1R agonists, glucagon receptor (GCGR) agonists act directly on the liver to stimulate fatty acid oxidation and inhibit lipogenesis, potentially providing a more potent mechanism for liver fat content (LFC) reduction than weight loss alone. This study demonstrated the ability of once-weekly treatment with pemvidutide, a dual GLP-1R/GCGR agonist, to significantly reduce LFC, hepatic inflammatory activity, and body weight, suggesting that pemvidutide may be an effective treatment for both MASH and obesity.

CLINICAL TRIAL NUMBER

NCT05006885.

Safety of native glucose-dependent insulinotropic polypeptide in humans

In this systematic review, we assessed the safety and possible safety events of native glucose-dependent insulinotropic polypeptide (GIP)(1-42) in human studies with administration of synthetic human GIP. We searched the PubMed database for all trials investigating synthetic human GIP(1-42) administration. A total of 67 studies were included. Study duration ranged from 30 min to 6 days. In addition to healthy individuals, the studies included individuals with impaired glucose tolerance, type 2 diabetes, type 1 diabetes, chronic pancreatitis and secondary diabetes, latent autoimmune diabetes in adults, diabetes caused by a mutation in the hepatocyte nuclear factor 1-alpha gene, end-stage renal disease, chronic renal insufficiency, critical illness, hypoparathyroidism, or cystic fibrosis-related diabetes. Of the included studies, 78% did not mention safety events, 10% of the studies reported that no safety events were observed in relation to GIP administration, and 15% of the studies reported safety events in relation to GIP administration with most frequently reported event being a moderate and transient increased heart rate. Gastrointestinal safety events, and changes in blood pressure were also reported. Plasma concentration of active GIP(1-42) increased linearly with dose independent of participant phenotype. There was no significant correlation between achieved maximal concentration of GIP(1-42) and reported safety events. Clearance rates of GIP(1-42) were similar between participant groups. In conclusion, the available data indicate that GIP(1-42) in short-term (up to 6 days) infusion studies is generally well-tolerated. The long-term safety of continuous GIP(1-42) administration is unknown.

Glucagon-like peptide-1 receptor agonists: a narrative review of clinical pharmacology and implications for peri-operative practice

BACKGROUND

Glucagon-like peptide-1 receptor agonists are used increasingly in the management of patients living with type 2 diabetes mellitus and obesity. In patients using glucagon-like peptide-1 receptor agonists, a key concern in the peri-operative period is the increased risk of pulmonary aspiration due to delayed gastric emptying. This review provides an overview of the pharmacodynamic and pharmacokinetic properties of glucagon-like peptide-1 receptor agonists and the risk of delayed gastric emptying and aspiration.

METHODS

We conducted searches of MEDLINE and EMBASE databases of articles published before January 2024 using the keywords and medical subject headings: incretins; glucagon-like peptide-1; GLP-1; glucagon-like peptide-1 receptor agonists; GLP-1 RA; peri-operative period; perioperative; peri-operative; stomach emptying; gastric emptying; pulmonary aspiration; aspiration; food regurgitation; and regurgitation. The evidence was analysed, synthesised and reported narratively.

RESULTS

A total of 1213 articles were located after duplicates were removed. Two authors screened the titles and abstracts to identify those studies which assessed specifically the risk of delayed gastric emptying and pulmonary aspiration or regurgitation in the peri-operative period. We searched manually the reference lists of relevant studies to identify any additional case reports. Ten studies were identified. Available evidence was limited to case reports, case series and observational work.

CONCLUSIONS

There is insufficient evidence to put forward definitive guidance regarding the ideal cessation period for glucagon-like peptide-1 receptor agonists before elective surgery. Precautionary practice is required until more evidence becomes available. We suggest an individualised, evidence-based approach. In patients living with type 2 diabetes mellitus, there is concern that prolonged cessation before surgery will have a detrimental effect on peri-operative glycaemic control and discussion with an endocrinologist is advised. For patients taking glucagon-like peptide-1 receptor agonists for weight management, these drugs should be withheld for at least three half-lives before an elective surgical procedure.

Drug release profile of a novel exenatide long-term drug delivery system (OKV-119) administered to cats

Beneficial weight-loss properties of glucagon-like peptide-1 receptor agonists (GLP-1RA) in obese people, with corresponding improvements in cardiometabolic risk factors, are well established. OKV-119 is an investigational drug delivery system that is being developed for the long-term delivery of the GLP-1RA exenatide to feline patients. The purpose of this study was to evaluate the drug release characteristics of subcutaneous OKV-119 implants configured to release exenatide for 84 days. Following a 7-day acclimation period, five purpose-bred cats were implanted with OKV-119 protypes and observed for a 112-day study period. Food intake, weekly plasma exenatide concentrations and body weight were measured. Exenatide plasma concentrations were detected at the first measured timepoint (Day 7) and maintained above baseline for over 84 Days. Over the first 28 days, reduced caloric intake and a reduction in body weight were observed in four of five cats. In these cats, a body weight reduction of at least 5% was maintained throughout the 112-day study period. This study demonstrates that a single OKV-119 implant can deliver the GLP-1RA exenatide for a months long duration. Results suggest that exposure to exenatide plasma concentrations ranging from 1.5 ng/ml to 4 ng/ml are sufficient for inducing weight loss in cats.

Sodium-Glucose Cotransporter 2 Inhibitors Reduce the Risk of Hospitalization for Heart Failure and Amputation Rate Compared With Incretin-Based Therapy in Patients With Diabetic Foot Disease: A Nationwide Population-Based Study

OBJECTIVE

Major adverse cardiovascular event (MACE) outcomes associated with sodium-glucose cotransporter 2 inhibitor (SGLT2i) and glucagon-like peptide-1 receptor agonist (GLP-1 RA) therapies remain unclear in patients with type 2 diabetes and newly diagnosed diabetic foot complications (DFCs). This study examined the impact of SGLT2i and GLP-1 RA use on the rates of MACEs and amputations in patients with type 2 diabetes and without cardiovascular disease.

METHODS

Data from the Taiwan National Health Insurance Research Database (2004-2017) were analyzed, focusing on patients with type 2 diabetes without previous MACE and newly diagnosed DFCs. The primary outcome was the first MACE occurrence, and the secondary outcomes included MACE components, all-cause mortality, and lower extremity amputation (LEA) rates.

RESULTS

SGLT2i users showed a significant decrease in the MACE (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.46-0.88) and hospitalization for heart failure (HR, 0.54; 95% CI, 0.35-0.83) rates compared with dipeptidyl peptidase-4 inhibitor users. The amputation rates were also lower in SGLT2i users without LEA at the first DFC diagnosis (HR, 0.28; 95% CI, 0.10-0.75) and did not increase in those with a history of peripheral artery disease or LEA. No significant differences were observed between dipeptidyl peptidase-4 inhibitor and GLP-1 RA users in terms of the primary or secondary outcomes.

CONCLUSION

In patients with type 2 diabetes initially diagnosed with DFC, SGLT2i are effective in significantly reducing the hospitalization for heart failure and MACE rates. SGLT2i lower the amputation rates, especially in patients who have not previously had a LEA, than the dipeptidyl peptidase-4 inhibitor therapy.

Glucagon-like peptide-1 receptor agonists: new strategies and therapeutic targets to treat atherosclerotic cardiovascular disease

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of cardiovascular mortality and is increasingly prevalent in our population. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) can safely and effectively lower glucose levels while concurrently managing the full spectrum of ASCVD risk factors and improving patients' long-term prognosis. Several cardiovascular outcome trials (CVOTs) have been carried out to further investigate the cardiovascular benefits of GLP-1RAs. Analyzing data from CVOTs can provide insights into the pathophysiologic mechanisms by which GLP-1RAs are linked to ASCVD and define the use of GLP-1RAs in clinical practice. Here, we discussed various mechanisms hypothesized in previous animal and preclinical human studies, including blockade of the production of adhesion molecules and inflammatory factors, induction of endothelial cells' synthesis of nitric oxide, protection of mitochondrial function and restriction of oxidative stress, suppression of NOD-like receptor thermal protein domain associated protein three inflammasome, reduction of foam cell formation and macrophage inflammation, and amelioration of vascular smooth muscle cell dysfunction, to help explain the cardiovascular benefits of GLP-1RAs in CVOTs. This paper provides an overview of the clinical research, molecular processes, and possible therapeutic applications of GLP-1RAs in ASCVD, while also addressing current limitations in the literature and suggesting future research directions.

The antiemetic actions of GIP receptor agonism

Nausea and vomiting are primitive aspects of mammalian physiology and behavior that ensure survival. Unfortunately, both are ubiquitously present side effects of drug treatments for many chronic diseases with negative consequences on pharmacotherapy tolerance, quality of life, and prognosis. One of the most critical clinical examples is the profound emesis and nausea that occur in patients undergoing chemotherapy, which continue to be among the most distressing side effects, even with the use of modern antiemetic medications. Similarly, antiobesity/diabetes medications that target the glucagon-like peptide-1 system, despite their remarkable metabolic success, also cause nausea and vomiting in a significant number of patients. These side effects hinder the ability to administer higher dosages for optimal glycemic and weight management and represent the major reasons for treatment discontinuation. Our inability to effectively control these side effects highlights the need to anatomically, molecularly, and functionally characterize novel neural substrates that drive and inhibit nausea and emesis. Here, we discuss clinical and preclinical evidence that highlights the glucose-dependent insulinotropic peptide receptor system as a novel therapeutic central target for the management of nausea and emesis.

Engineering of a Biologically Active Glycosylated Glucagon-Like Peptide-1 Analogue

Glucagon-like peptide receptor (GLP-1R) agonists (e.g., semaglutide, liraglutide, etc.) are efficient treatment options for people with type 2 diabetes and obesity. The manufacturing method to produce semaglutide, a blockbuster GLP-1 drug on the market, involves multistep synthesis. The large peptide has a hydrophobic fatty acid side chain that makes it sparingly soluble, and its handling, purification, and large-scale production difficult. The growing demand for semaglutide that the manufacturer is not capable of addressing immediately triggered a worldwide shortage. Thus, we have developed a potential alternative analogue to semaglutide by replacing the hydrophobic fatty acid with a hydrophilic human complex-type biantennary oligosaccharide. Our novel glycoGLP-1 analogue was isolated in an ∼10-fold higher yield compared with semaglutide. Importantly, our glycoGLP-1 analogue possessed a similar GLP-1R activation potency to semaglutide and was biologically active in vivo in reducing glucose levels to a similar degree as semaglutide.

Safety, pharmacokinetics and pharmacodynamics of HRS-7535, a novel oral small molecule glucagon-like peptide-1 receptor agonist, in healthy participants: A phase 1, randomized, double-blind, placebo-controlled, single- and multiple-ascending dose, and food effect trial

AIM

To assess the safety, tolerability, pharmacokinetics (PKs) and pharmacodynamics of HRS-7535, a novel glucagon-like peptide-1 receptor agonist (GLP-1RA), in healthy participants.

MATERIALS AND METHODS

This phase 1 trial consisted of single-ascending dose (SAD), food effect (FE) and multiple-ascending dose (MAD) parts. In the SAD part, participants were randomized (6:2) to receive HRS-7535 (at doses of 15, 60 and 120 mg; administered orally once daily) or placebo. In the FE part, participants were randomized (8:2) to receive a single dose of 90-mg HRS-7535 or placebo, in both fed and fasted states. In the MAD part, participants were randomized (18:6) to receive daily HRS-7535 (120 mg [30/60/90/120-mg titration scheme]) or placebo for 28 days. The primary endpoints were safety and tolerability.

RESULTS

Nausea and vomiting were the most frequently reported AEs across all three parts. In the SAD part, the median Tmax was 5.98-5.99 hours and the geometric mean t1/2 was 5.28-9.08 hours across the HRS-7535 dosing range. In the MAD part, the median Tmax was 5.98-10.98 hours and the geometric mean t1/2 was 6.48-8.42 hours on day 28 in participants on HRS-7535. PKs were approximately dose-proportional. On day 29 in the MAD part, the mean (percentage) reduction in body weight from baseline was 4.38 kg (6.63%) for participants who received HRS-7535, compared with 0.8 kg (1.18%) for those participants who received a placebo.

CONCLUSIONS

HRS-7535 exhibited a safety and tolerability profile consistent with other GLP-1RAs and showed PKs suitable for once-daily dosing. These findings support further clinical development of HRS-7535 for type 2 diabetes.

Psychiatric adverse events associated with GLP-1 receptor agonists: a real-world pharmacovigilance study based on the FDA Adverse Event Reporting System database

Background

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are widely used due to their profound efficacy in glycemic control and weight management. Within real-world contexts, the manifestation of certain psychiatric adverse events (AEs) has been observed, which is potentially linked to the administration of GLP-1 RAs. The objective of this study was to undertake a comprehensive investigation and characterization of the psychiatric AEs associated with GLP-1 RAs.

Methods

We retrieved reports of AEs associated with treatment with GLP-1 RAs during the period from the first quarter (Q1) of 2004 to Q1 2023 from the FDA Adverse Event Reporting System (FAERS) database. Descriptive analysis was performed to examine the clinical characteristics and time to onset of the psychiatric AEs caused by GLP-1 RAs. Moreover, disproportionality analyses were performed using the reporting odds ratio (ROR) to identify GLP-1 RA-related psychiatric AEs.

Results

A total of 8,240 reports of psychiatric AEs were analyzed out of 181,238 AE reports with treatment with GLP-1 RAs. Among these cases, a higher percentage was represented by women compared to men (65.89% vs. 30.96%). The median age of these patients was 56 years, with an interquartile range (IQR) of 48-67 years, based on data available in 286 case reports. This study showed that the median time to onset of the overall GLP-1 RA-related AEs was 31 days (IQR = 7-145.4 days), which varied among GLP-1 RA regimens. Specifically, exenatide had a significantly longer onset time at 45 days (IQR = 11-213 days), with statistically significant differences from the onset times of the other five GLP-1 RAs (p< 0.0001). Moreover, eight categories of psychiatric AEs, namely, nervousness (ROR = 1.97, 95% CI = 1.85-2.11), stress (ROR = 1.28, 95% CI = 1.19-1.38), eating disorder (ROR = 1.57, 95% CI = 1.40-1.77), fear of injection (ROR = 1.96, 95% CI = 1.60-2.40), sleep disorder due to general medical condition-insomnia type (ROR = 2.01, 95% CI = 1.60-2.52), binge eating (ROR = 2.70, 95% CI = 1.75-4.16), fear of eating (ROR 3.35, 95% CI = 1.65-6.78), and self-induced vomiting (ROR = 3.77, 95% CI = 1.77-8.03), were defined as GLP-1 RA-related psychiatric AEs through disproportionality analysis.

Conclusion

Our findings demonstrate a significant association between GLP-1 RAs and the development of specific psychiatric AEs. Despite the observational nature of this pharmacovigilance study and the inherent limitations of the FAERS database, our preliminary findings in this work could provide a better basis for understanding the potential psychiatric AEs that may occur with GLP-1 RA treatment, assisting clinicians to focus on these AEs and provide early intervention for optimal risk management.

Meta-Analysis on the Association Between DPP-4 Inhibitors and Bone Mineral Density and Osteoporosis

Background Type 2 Diabetes Mellitus (T2DM) frequently coexists with osteoporosis and reduced bone mineral density (BMD). Dipeptidyl peptidase-4 inhibitors (DPP-4i), a class of antihyperglycemic agents, are commonly employed in T2DM treatment. However, the influence of DPP-4i on bone health remains unclear and debated. This meta-analysis is conducted to explore the relationship between the use of DPP-4i and changes in BMD, as well as the prevalence of osteoporosis among T2DM patients. Methods We conducted a comprehensive search in PubMed, Embase, and Cochrane Library and Web of Science databases for relevant studies published up until June 2023. Studies included in the meta-analysis were those investigating T2DM patients under DPP-4i treatment, and examining the effects on BMD and osteoporosis. Random-effects models and fixed-effect models were utilized to compute the pooled effects. Heterogeneity among the included studies was evaluated using I² statistics. Results This meta-analysis incorporated a total of 10 studies, encompassing a combined population of 214,541 individuals. The results from this meta-analysis indicated an increase in BMD following DPP-4i usage (SMD 0.15, 95 % confidence interval 0.03-0.26). Additionally, the risk of osteoporosis was significantly reduced (OR 0.90, 95 % confidence interval 0.86-0.94) with very low heterogeneity, recorded at 0 % and 53.0 % respectively. No publication bias was detected in the funnel plot, and sensitivity analyses affirmed the stability of the study's conclusions. Conclusion Our results offer valuable insights into the positive impact of DPP-4i on bone health in T2DM patients, contributing to informed clinical decision-making. These findings may inform the development of more comprehensive T2DM management strategies that account for bone health.

The role of anti-diabetic drugs in NAFLD. Have we found the Holy Grail? A narrative review

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) has become a leading cause of liver disease, affecting 30% of the global population. NAFLD prevalence is particularly high in obese individuals and patients with type 2 diabetes mellitus (T2DM). NAFLD ranges from simple fat deposition in the liver to necroinflammation and fibrosis (non-alcoholic steatohepatitis (NASH)), NASH-cirrhosis, and/or hepatocellular carcinoma. Insulin resistance plays a key role in NAFLD pathogenesis, alongside dysregulation of adipocytes, mitochondrial dysfunction, genetic factors, and changes in gut microbiota. Since insulin resistance is also a major predisposing factor of T2DM, the administration of anti-diabetic drugs for the management of NAFLD seems reasonable.

METHODS

In this review we provide the NAFLD-associated mechanisms of action of some of the most widely used anti-diabetic drugs, namely metformin, pioglitazone, sodium-glucose transport protein-2 inhibitors (SGLT2i), glucagon-like peptide 1 receptor analogs (GLP1 RAs), and dipeptyl-peptidase-4 inhibitors (DPP4i) and present available data regarding their use in patients with NAFLD, with and without T2DM.

RESULTS

Both metformin and DPP4i have shown rather contradictory results, while pioglitazone seems to benefit patients with NASH and is thus the only drug approved for NASH with concomitant significant liver fibrosis by all major liver societies. On the other hand, SGLT2i and GLP1 RAs seem to be beneficiary in patients with NAFLD, showing both remarkable results, with SGLT2i proving to be more efficient in the only head-to-head study so far.

CONCLUSION

In patients with NAFLD and diabetes, pioglitazone, GLP1 RAs, and SGLT2i seem to be logical treatment options. Larger studies are needed before these drugs can be recommended for non-diabetic individuals.

Safety and effectiveness of dulaglutide in Chinese adults with type 2 diabetes mellitus in a real-world setting: A prospective, observational post-marketing study

AIM

To our knowledge, this is the first real-world study to investigate the safety and effectiveness of a glucagon-like peptide-1 receptor agonist in Chinese patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

This prospective, observational, post-marketing study conducted at 46 hospitals in China included adults with T2DM prescribed dulaglutide in routine clinical practice. The primary endpoint was the incidence of treatment-emergent adverse events (TEAEs) and serious AEs in patients who received ≥1 dose of dulaglutide, for up to 24 weeks. Exploratory endpoints included changes in patient-reported glycated haemoglobin (HbA1c) and body weight. Post hoc analyses and multivariate regression were also performed.

RESULTS

From 20 January 2020 to 24 November 2021, 3291 patients received dulaglutide and entered the safety analysis. TEAEs were reported in 1333 (40.5%) patients; the most commonly reported were nausea (n = 193, 5.9%), diarrhoea (n = 183, 5.6%) and decreased appetite (n = 179, 5.4%). serious AEs were reported in 160 (4.9%) patients. TEAEs led to treatment discontinuation in 212 (6.4%) patients. The mean absolute change in HbA1c from baseline to week 24 was -1.65% (p < .001). Greater reductions in HbA1c at week 24 were observed in patients with T2DM duration ≤5 years (p = .002), baseline HbA1c ≥8.5% (p < .001), and without atherosclerotic cardiovascular disease (p = .002). The mean absolute change in body weight from baseline at week 24 was -2.62 kg (p < .001).

CONCLUSION

Dulaglutide showed a safety profile consistent with previous reports and significantly reduced HbA1c in a real-world setting. These findings support the clinical use of dulaglutide and inform the individualized treatment of patients with T2DM in China.

Endogenous glucagon-like peptide (GLP)-1 as alternative for GLP-1 receptor agonists: Could this work and how?

In recent years, we have witnessed the many beneficial effects of glucagon-like peptide (GLP)-1 receptor agonists, including the reduction in cardiovascular risk in patients with type 2 diabetes, and the reduction of body weight in those with obesity. Increasing evidence suggests that these agents differ considerably from endogenous GLP-1 when it comes to their routes of action, although their clinical effects appear to be the same. Given the limitations of the GLP-1 receptor agonists, could it be useful to develop agents which stimulate GLP-1 release? Here we will discuss the differences and similarities between GLP-1 receptor agonists and endogenous GLP-1, and will detail how endogenous GLP-1-when stimulated appropriately-could have clinically relevant effects.

Treatment intensification following glucagon-like peptide-1 receptor agonist treatment in type 2 diabetes: The RESTORE-G real-world study

BACKGROUND AND AIMS

To assess intensification approaches with basal insulin (BI) following glucagon-like peptide-1 receptor agonist (GLP-1 RA) treatment in type 2 diabetes (T2D).

METHODS AND RESULTS

Real-world data were collected in electronic medical records by 32 Italian diabetes clinics between 2011 and 2021. Primary endpoint was the proportion of insulin-naïve T2D patients treated with GLP-1 RA who initiated (add-on or switch) BI. Secondary endpoints were: treatment approaches, mean time to BI start, effectiveness and safety. Among 7,962 eligible patients, BI was prescribed to 3,164 (39.7%; 95%CI 38.7; 40.8): 67.6% switched to BI (22.1% also starting 1-3 injections of short-acting insulin), 22.7% added BI while maintaining GLP-1 RA, and 9.7% switched to a fixed-ratio combination of GLP-1 RA and BI (FRC). Median time since the first GLP-1 RA to BI/FRC prescription was 27.4 (IQ range 11.8-53.5) months. In this study 60.3% of patients did not start BI/FRC, among whom 15.2% intensified GLP-1 RA therapy with other oral agents. Effectiveness and safety were documented in all intensification approaches with BI/FRC, but HbA1c level at intensification time of ≥9.0% and suboptimal BI titration suggested clinical inertia. Use of second generation BI and add-on to GLP-1 RA schemes increased over time and effectiveness improved.

CONCLUSION

Clinical inertia should be overcome using innovative insulin options. Timely combination therapy of BI and GLP-1 RA is a valuable choice.

The effect of GLP-1 receptor agonist lixisenatide on experimental diabetic retinopathy

AIMS

Glucagon-like peptide-1 receptor agonists are effective treatments for type 2 diabetes, effectively lowering glucose without weight gain and with low risk for hypoglycemia. However, their influence on the retinal neurovascular unit remains unclear. In this study, we analyzed the effects of the GLP-1 RA lixisenatide on diabetic retinopathy.

METHODS

Vasculo- and neuroprotective effects were assessed in experimental diabetic retinopathy and high glucose-cultivated C. elegans, respectively. In STZ-diabetic Wistar rats, acellular capillaries and pericytes (quantitative retinal morphometry), neuroretinal function (mfERG), macroglia (GFAP western blot) and microglia (immunohistochemistry) quantification, methylglyoxal (LC-MS/MS) and retinal gene expressions (RNA-sequencing) were determined. The antioxidant properties of lixisenatide were tested in C. elegans.

RESULTS

Lixisenatide had no effect on glucose metabolism. Lixisenatide preserved the retinal vasculature and neuroretinal function. The macro- and microglial activation was mitigated. Lixisenatide normalized some gene expression changes in diabetic animals to control levels. Ets2 was identified as a regulator of inflammatory genes. In C. elegans, lixisenatide showed the antioxidative property.

CONCLUSIONS

Our data suggest that lixisenatide has a protective effect on the diabetic retina, most likely due to a combination of neuroprotective, anti-inflammatory and antioxidative effects of lixisenatide on the neurovascular unit.

Alcoholic drink produced by pea is a risk factor for incident knee surgery in patients with knee osteoarthritis

Objective

The objective of this study is to investigate whether alcohol exposure and specific alcoholic drinks are independent risk factors for incident knee surgery in knee osteoarthritis (KOA) patients.

Methods

We identified all patients who were clinically diagnosed as KOA between January 2010 and January 2018 in our outpatient department. Demographic, clinical, and radiographic data were collected from the database of our hospital. Next, we analyzed the association between alcohol consumption and incident knee surgery.

Results

A total of 4,341 KOA patients completed the current study and were included in the final analysis. Incident knee surgery for the purpose of treating osteoarthritis was observed in 242 patients. Incident knee surgery was significantly associated with age (OR [95%CI], 1.023 [1.009-1.039], P = 0.002), BMI (OR [95%CI], 1.086 [1.049-1.123], P < 0.001), baseline K-L grade 3 (OR [95%CI], 1.960 [1.331-2.886], P = 0.001), baseline K-L grade 4 (OR [95%CI], 1.966 [1.230-3.143], P = 0.005), 7.1-14 drinks per week (OR [95%CI], 2.013 [1.282-3.159], P = 0.002), >14 standard drinks per week (OR [95%CI], 2.556 [1.504-4.344], P = 0.001), and the most common alcoholic drink produced by pea (OR [95%CI], 3.133 [1.715-5.723], P < 0.001).

Conclusion

KOA patients who consumed more than seven standard drinks per week were at substantial risk of incident knee surgery. In addition, alcoholic drink produced by pea is also an independent risk factor.

Real-world use of glucagon-like peptide-1 receptor agonists in Japanese patients with type 2 diabetes: A retrospective database study (DEFINE-G)

AIMS

To understand glucagon-like peptide-1 receptor agonist (GLP-1RA) use in patients with type 2 diabetes (T2D) in Japan.

METHODS

Characteristics of people receiving GLP-1RAs between 2016 and 2020 in the J-DREAMS database were investigated. Changes in HbA1c, body weight (BW), body mass index (BMI), and proportion reaching HbA1c targets were analysed in GLP-1RA-naïve patients 6-24 months after GLP-1RA initiation.

RESULTS

The proportion of patients with GLP-1RA prescriptions increased from 3.6% to 9.6% during 2016-2020. Among GLP-1RA-naïve patients (n = 569), HbA1c reduced -‍0.6% (95% confidence interval [CI] -0.7, -0.5; -6 mmol/mol [95% CI -7, -5]) 6 months after treatment initiation and stabilised until 24 months (P < 0.001); mean BW and BMI reduced -1.05 kg (95% CI -1.31, -0.80) and -0.43 kg/m2 (95% CI -0.53, -0.32), respectively, at 6 months (P < 0.001). The proportion of GLP-1RA-naïve patients with HbA1c < 7.0% (<53 mmol/mol) and <8.0% (<64 mmol/mol) increased from 16% to 27% and 43% to 65%, respectively, and an HbA1c reduction of ≥1.0% (≥11 mmol/mol) was observed in 33% of patients after 6 months (P < 0.001).

CONCLUSIONS

This study shows increased GLP-1RA prescriptions over 5 years. HbA1c and BW reduced 6 months after GLP-1RA initiation in patients with T2D in a Japanese real-world setting.

Glucagon-like peptide-1 receptor agonists as a disease-modifying therapy for knee osteoarthritis mediated by weight loss: findings from the Shanghai Osteoarthritis Cohort

OBJECTIVE

Obesity is a risk factor for knee osteoarthritis (KOA) development and progression. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are indicated for type 2 diabetes mellitus (T2DM) and obesity. However, whether KOA patients can benefit from GLP-1RA therapies has not been sufficiently investigated, especially in the long term.

METHODS

The Shanghai Osteoarthritis Cohort study is a prospective, observational, multicentre study of >40 000 adults with clinically diagnosed osteoarthritis aged >45 years in Shanghai. We identified all KOA participants with comorbid T2DM enrolled from 1 January 2011 to 1 January 2017. Primary outcome was incidence of knee surgery after enrolment. Secondary outcomes included pain-relieving medication use, number of intra-articular therapies, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and medial femorotibial joint cartilage thickness. To evaluate the effects of GLP-1RA, we performed before-and-after comparison and comparison with participants who had no GLP-1RA exposure.

RESULTS

For an intergroup comparison (non-GLP-1RA vs GLP-1RA), more weight loss (adjusted mean difference in weight change from baseline -7.29 kg (95% CI -8.07 to -6.50 kg), p<0.001) and lower incidence of knee surgery (93/1574 (5.9%) vs 4/233 (1.7%), adjusted p=0.014) were observed in the GLP-1RA group. Statistically significant differences in mean change from baseline for the WOMAC total and pain subscale scores were observed (adjusted mean difference in WOMAC total score -1.46 (95% CI -2.84 to -0.08), p=0.038; adjusted mean difference in WOMAC pain subscore -3.37 (95% CI -5.79 to -0.94), p=0.007). Cartilage-loss velocity of the medial femorotibial joint was significantly lower in the GLP-1RA group postadjustment for baseline characteristics (adjusted mean difference -0.02 mm (95% CI -0.03 to -0.002 mm), p=0.004). For the before-and-after comparison within the GLP-1RA group, we observed a significant decrease of symptom-relieving medication consumption and cartilage loss velocity of medial femorotibial joint (after-treatment vs before-treatment: -0.03±0.05 vs -0.05±0.07 mm/year, p<0.001). The association between GLP-1RA exposure and decreased incidence of knee surgery was mediated by weight reduction (mediation proportion: 32.1%), instead of glycaemic control (too small to calculate).

CONCLUSION

With sufficient treatment duration, GLP-1RA therapies might be disease-modifying for KOA patients with comorbid T2DM, possibly mediated by weight loss. Further investigation is needed to elucidate effects of GLP-1RA on disease process, joint structure and patient-reported outcomes of osteoarthritis.

Current Understanding of Sodium N-(8-[2-Hydroxylbenzoyl] Amino) Caprylate (SNAC) as an Absorption Enhancer: The Oral Semaglutide Experience

Oral administration of peptide therapeutics faces challenges because of the distinct environment of the gastrointestinal tract. An oral formulation of semaglutide, a glucagon-like peptide 1 receptor agonist, was approved by the U.S. Food and Drug Administration in 2019 as a peptide therapy for the treatment of type 2 diabetes. Oral semaglutide uses sodium N-(8-[2-hydroxybenzoyl] amino) caprylate (SNAC) technology to enhance the absorption of semaglutide in the stomach and protect it from degradation by gastric enzymes. This article presents a summary of studies investigating SNAC technology as an absorption enhancer for a number of molecules and, in particular, explores how SNAC, once coformulated with oral semaglutide, facilitates increased absorption and bioavailability. Practical advice and dispensing information for pharmacists is also provided.

A Phase 1 Multiple Dose Study of Tirzepatide in Chinese Patients with Type 2 Diabetes

INTRODUCTION

To investigate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of tirzepatide in Chinese patients with type 2 diabetes (T2D).

METHODS

In this phase 1, double-blind, placebo-controlled, multiple dose study, patients were randomized into one of two cohorts to receive once-weekly subcutaneous tirzepatide or placebo. The initial tirzepatide dose in both cohorts was 2.5 mg, which was increased by 2.5 mg every 4 weeks to a maximum final dose of 10.0 mg at week 16 (Cohort 1) or 15.0 mg at week 24 (Cohort 2). The primary outcome was the safety and tolerability of tirzepatide.

RESULTS

Twenty-four patients were randomized (tirzepatide 2.5-10.0 mg: n = 10, tirzepatide 2.5-15.0 mg: n = 10, placebo: n = 4); 22 completed the study. The most frequently reported treatment-emergent adverse events (TEAEs) among patients receiving tirzepatide were diarrhea and decreased appetite; most TEAEs were mild and resolved spontaneously with no serious adverse events reported in the tirzepatide groups and one in the placebo group. The plasma concentration half-life of tirzepatide was approximately 5-6 days. Mean glycated hemoglobin (HbA1c) decreased over time from baseline in the 2.5-10.0 mg (- 2.4%) and 2.5-15.0 mg (- 1.6%) tirzepatide groups, at week 16 and week 24, respectively, but remained steady in patients receiving placebo. Body weight decreased from baseline by - 4.2 kg at week 16 in the tirzepatide 2.5-10.0 mg group and by - 6.7 kg at week 24 in the 2.5-15.0 mg group. Mean fasting plasma glucose levels fell from baseline by - 4.6 mmol/L in the tirzepatide 2.5-10.0 mg group at week 16 and by - 3.7 mmol/L at week 24 in the tirzepatide 2.5-15.0 mg group.

CONCLUSIONS

Tirzepatide was well tolerated in this population of Chinese patients with T2D. The safety, tolerability, PK, and PD profile of tirzepatide support once-weekly dosing in this population.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT04235959.

Antidiabetic agents as a novel treatment for Alzheimer's and Parkinson's disease

Therapeutic strategies for neurodegenerative disorders have commonly targeted individual aspects of the disease pathogenesis to little success. Neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD), are characterized by several pathological features. In AD and PD, there is an abnormal accumulation of toxic proteins, increased inflammation, decreased synaptic function, neuronal loss, increased astrocyte activation, and perhaps a state of insulin resistance. Epidemiological evidence has revealed a link between AD/PD and type 2 diabetes mellitus, with these disorders sharing some pathological commonalities. Such a link has opened up a promising avenue for repurposing antidiabetic agents in the treatment of neurodegenerative disorders. A successful therapeutic strategy for AD/PD would likely require a single or several agents which target the separate pathological processes in the disease. Targeting cerebral insulin signalling produces numerous neuroprotective effects in preclinical AD/PD brain models. Clinical trials have shown the promise of approved diabetic compounds in improving motor symptoms of PD and preventing neurodegenerative decline, with numerous further phase II trials and phase III trials underway in AD and PD populations. Alongside insulin signalling, targeting incretin receptors in the brain represents one of the most promising strategies for repurposing currently available agents for the treatment of AD/PD. Most notably, glucagon-like-peptide-1 (GLP-1) receptor agonists have displayed impressive clinical potential in preclinical and early clinical studies. In AD the GLP-1 receptor agonist, liraglutide, has been demonstrated to improve cerebral glucose metabolism and functional connectivity in small-scale pilot trials. Whilst in PD, the GLP-1 receptor agonist exenatide is effective in restoring motor function and cognition. Targeting brain incretin receptors reduces inflammation, inhibits apoptosis, prevents toxic protein aggregation, enhances long-term potentiation and autophagy as well as restores dysfunctional insulin signalling. Support is also increasing for the use of additional approved diabetic treatments, including intranasal insulin, metformin hydrochloride, peroxisome proliferator-activated nuclear receptor γ agonists, amylin analogs, and protein tyrosine phosphatase 1B inhibitors which are in the investigation for deployment in PD and AD treatment. As such, we provide a comprehensive review of several promising anti-diabetic agents for the treatment of AD and PD.

Roles of microRNA-192 in diabetic nephropathy: the clinical applications and mechanisms of action

Diabetic nephropathy (DN) is one of the most common and intractable microvascular complications of diabetes worldwide, serving as the main cause of terminal renal disease. Due to the lack of early specific symptoms and diagnostic markers, DN severely threatens the sufferer's life. MicroRNA-192 (miR-192) was early identified in human renal cortical tissue and stored and excreted in urine as microvesicles. MiR-192 was found to be involved in the development of DN. For the first time, the present review summarized all the current evidence on the topic of the roles of miR-192 in DN. Finally, 28 studies (ten clinical trials and eighteen experimental studies) were eligible for thorough reviewing. Most of the clinical trials (7/10, 70%) indicated miR-192 might be a protective factor for DN development and progression, while the majority of experimental studies (14/18, 78%) suggested miR-192 might be a pathogenic factor for DN. Mechanistically, miR-192 interacts with various direct targeted proteins (i.e., ZEB1, ZEB2, SIP1, GLP1R, and Egr1) and signaling cascades (i.e., SMAD/TGF-β and PTEN/PI3K/AKT), together contribute to the pathogenesis of DN through epithelial-to-mesenchymal transition (EMT), extracellular matrix deposition, and fibrosis formation. The current review highlights the dual role of miR-192 in the development of DN. Low serum miR-192 expression could be applied for the early prediction of DN (the early stage of DN), while the high miR-192 level in renal tissues and urine may imply the progression of DN (the late stage of DN). Further investigations are still warranted to illustrate this inconsistent phenomenon, which may facilitate promoting the therapeutic applications of miR-192 in predicting and treating DN.

Clinical Characteristics Associated with Adherence and Persistence in Patients with Type 2 Diabetes Mellitus Treated with Dulaglutide

Aims

This study is aimed at identifying clinical characteristics associated with adherence and persistence in patients with type 2 diabetes mellitus (T2DM) treated with dulaglutide.

Materials and Methods

This retrospective observational cohort study used the Common Data Model at Seoul National University Hospital, Seoul, South Korea. Eligible subjects were followed for one year. Multivariate logistic and linear regressions were used to identify the factors associated with categorical (i.e., adherence status and continuation status) and continuous (i.e., proportion of days covered, or PDC, and treatment duration) outcome measures, respectively. Subgroup analysis was conducted involving patients at high cardiovascular disease (CVD) risk (i.e., having ≥2 identifiable risk factors).

Results

A total of 236 patients were included. Increase in age and estimated glomerular filtration rate significantly increased the likelihood of adherence and treatment continuation. In contrast, baseline obesity and baseline use of sulfonylurea and insulin significantly reduced the likelihood of continuing dulaglutide. Similarly, increase in age, switching dulaglutide dose, and baseline neuropathy significantly increased PDC and treatment duration. None of the adherence or persistence outcome measures were significantly different between patients at high CVD risk and their matched controls. Baseline hypertension and the higher baseline LDL-C level significantly increased the likelihood of adherence in patients at high CVD risk.

Conclusion

Clinical characteristics of dulaglutide users that could have affected their adherence and persistence were identified. Physicians treating T2DM patients with dulaglutide can refer to those clinical characteristics identified in this study to optimize the adherence and persistence to dulaglutide.

Tirzepatide versus insulin glargine as second-line or third-line therapy in type 2 diabetes in the Asia-Pacific region: the SURPASS-AP-Combo trial

Tirzepatide is a once-weekly GIP/GLP-1 receptor agonist. In this phase 3, randomized, open-label trial, insulin-naive adults (≥18 years of age) with type 2 diabetes (T2D) uncontrolled on metformin (with or without a sulphonylurea) were randomized 1:1:1:1 to weekly tirzepatide 5 mg, 10 mg or 15 mg or daily insulin glargine at 66 hospitals in China, South Korea, Australia and India. The primary endpoint was non-inferiority of mean change in hemoglobin A1c (HbA1c) from baseline to week 40 after treatment with 10 mg and 15 mg of tirzepatide. Key secondary endpoints included non-inferiority and superiority of all tirzepatide doses in HbA1c reduction, proportions of patients achieving HbA1c < 7.0% and weight loss at week 40. A total of 917 patients (763 (83.2%) in China) were randomized to tirzepatide 5 mg (n = 230), 10 mg (n = 228) or 15 mg (n = 229) or insulin glargine (n = 230). All doses of tirzepatide were non-inferior and superior to insulin glargine for least squares mean (s.e.) reduction in HbA1c from baseline to week 40: tirzepatide 5 mg, 10 mg and 15 mg, -2.24% (0.07), -2.44% (0.07) and -2.49% (0.07), respectively, and insulin glargine, -0.95% (0.07), with a treatment difference ranging from -1.29% to -1.54% (all P < 0.001). Proportions of patients achieving HbA1c < 7.0% at week 40 were greater in tirzepatide 5-mg (75.4%), 10-mg (86.0%) and 15-mg (84.4%) groups compared to insulin glargine (23.7%) (all P < 0.001). All tirzepatide doses led to superior body weight reduction at week 40: tirzepatide 5 mg, 10 mg and 15 mg, -5.0 kg (-6.5%), -7.0 kg (-9.3%) and -7.2 kg (-9.4%), respectively, compared to insulin glargine, 1.5 kg (+2.1%) (all P < 0.001). The most common adverse events with tirzepatide were mild to moderate decreased appetite, diarrhea and nausea. No severe hypoglycemia was reported. Tirzepatide demonstrated superior reductions in HbA1c versus insulin glargine in an Asia-Pacific, predominately Chinese, population with T2D and was generally well tolerated. ClinicalTrials.gov registration: NCT04093752 .

Glucagon-like peptide-1 analog therapy in rare genetic diseases: monogenic obesity, monogenic diabetes, and spinal muscular atrophy

AIM

Implementing genetic analyses have unraveled rare alterations causing early-onset obesity and complications, in whom treatment is challenging. We aimed to report on the effects of adjuvant off-label therapy with liraglutide, glucagon-like peptide-1 analogue (GLP-1a), in rare genetic diagnoses.

METHODS

Case scenarios and review of the literature.

RESULTS

Case 1: Nine-year-old boy with early-onset severe obesity and nonalcoholic fatty liver disease (NAFLD) due to a homozygous mutation in the MC4R gene deteriorated under lifestyle change and metformin therapy [at 10.5 years: body mass index (BMI) 51.2kg/m², 226% of the 95th percentile, fat percentage (FP) 65% and muscle-to-fat ratio (MFR) z-score of -2.41]. One year of liraglutide treatment halted progressive weight gain [BMI 50.3kg/m², 212% of the 95th percentile, 63.7% FP and MFR z-score of -2.34], with biochemical improvement. Case 2: Twelve-year-old boy with obesity presented with diabetes and progressive NAFLD. Exome analysis revealed two heterozygous mutations compatible with monogenic diabetes (HNF1A) and familial hypercholesterolemia (LDLR). Lifestyle modifications resulted in clinical and laboratory improvement (BMI 87th percentile, 32.8% FP, MFR z-score of -1.63, HbA1c 5.5%) without the expected recovery in liver transaminases. Liraglutide treatment augmented the improvement in weight status (BMI 68th percentile, 22.6% FP, MFR z-score of -1.13) with normalization of liver transaminases. Case 3: Nineteen-year-old male with spinal muscular atrophy type 3 presented with sarcopenic obesity and comorbidities. Treatment strategy included dietary counseling and multiple drug therapies (metformin, anti-hypertensive and statins). Liraglutide therapy led to a gradual recovery of metabolic complications allowing tapering-down other medications.

CONCLUSIONS

Considering the pleiotropic effects of GLP1-a beyond BMI reduction, this treatment modality may serve as a game changer in challenging cases.

Cognitive protection of incretin-based therapies in patients with type 2 diabetes mellitus: A systematic review and meta-analysis based on clinical studies

AIMS/INTRODUCTION

Cognitive dysfunction, including mild cognitive impairment and dementia, is increasingly recognized as an important complication of type 2 diabetes mellitus. The aims of the preset study was to investigate the cognitive protection of incretin-based therapies, including glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors, in patients with type 2 diabetes mellitus.

MATERIALS AND METHODS

PubMed, EMBASE, Cochrane library, Web of Science and PsycINFO were searched from the inception through 17 January 2023 for randomized controlled trials and cohort studies on the association between incretin-based therapies and cognitive function. A total of 15 studies were finally included in our systematic review, and eight of which were incorporated into our meta-analysis.

RESULTS

Pooled results showed that the Mini-Mental State Examination score in incretin-based therapy groups was increased by 1.20 compared with the control group (weighted mean difference 1.20, 95% confidence interval 0.39-2.01). The results of eight studies assessed by the Newcastle Ottawa Quality Assessment Scale and the Cochrane Collaboration's tool, and the quality of the eight studies were at a relatively high level. Egger's regression did not show significant publication bias.

CONCLUSIONS

Current evidence shows that incretin-based therapies might be more effective, when compared with the other hypoglycemic drugs, for cognitive improvement in patients with type 2 diabetes mellitus.

Study design and baseline profile for adults with type 2 diabetes in the once-weekly subcutaneous SEmaglutide randomized PRAgmatic (SEPRA) trial

INTRODUCTION

Once-weekly subcutaneous semaglutide, a glucagon-like peptide-1 analog, is approved in the USA as an adjunct to diet and exercise for adults with inadequately controlled type 2 diabetes (T2D) to improve glycemic control and reduce the risk of major adverse cardiovascular events in people with T2D and established cardiovascular disease. The Semaglutide Unabated Sustainability in Treatment of Type 2 Diabetes (SUSTAIN) phase III clinical trial program demonstrated the efficacy and safety of once-weekly subcutaneous semaglutide; however, determining its effectiveness in a real-world setting could support decision-making by clinicians, payers and policy makers in routine clinical practice.

RESEARCH DESIGN AND METHODS

SEmaglutide PRAgmatic (SEPRA) is an ongoing open-label, randomized, pragmatic clinical trial designed to compare the effects of once-weekly subcutaneous semaglutide versus standard of care in US health-insured adults with T2D and physician-determined inadequate glycemic control. The primary end point is the proportion of participants achieving glycated hemoglobin (HbA1c) <7.0% at year 1; other key outcomes include glycemic control, weight loss, healthcare utilization, and patient-reported outcomes. Individual-level data will be collected from routine clinical practice and health insurance claims. The last patient last visit is expected by June 2023.

RESULTS

Between July 2018 and March 2021, 1278 participants were enrolled from 138 study sites across the USA. At baseline, 54% were male with mean±SD age 57.4±11.1 years and body mass index 35.7±8.0 kg/m2. Mean diabetes duration was 7.4±6.0 years and mean HbA1c was 8.5±1.6%. At baseline, concomitant antidiabetes medications included metformin, sulfonylureas, sodium-glucose co-transporter-2 inhibitors, and dipeptidyl peptidase-4 inhibitors. The majority of participants had hypertension and dyslipidemia. The trial design was self-assessed using the PRagmatic Explanatory Continuum Indicator Summary-2 tool by the study steering group and was scored 4-5 in all domains suggesting a highly pragmatic study.

CONCLUSIONS

SEPRA, a highly pragmatic ongoing study, will provide data on the effects of once-weekly subcutaneous semaglutide in a real-world setting when used during routine management of T2D.

TRIAL REGISTRATION NUMBER

NCT03596450.

TRIAL REGISTRATION NUMBER

GLP-1 Receptor Agonists Induce Growth Hormone Secretion in Healthy Volunteers

INTRODUCTION

Growth hormone (GH) is an essential regulator of growth, body composition and fuel metabolism and, consequently, GH secretion is under the feedback control of numerous nutritional and endocrine mediators. Glucagon-like peptide 1 receptor agonists (GLP-1RAs) have been shown to exert pleiotropic effects, including stimulation of the activity of the hypothalamic-pituitary-adrenal axis. As GLP-1RAs exert multiple metabolic effects, we hypothesised that they may also affect the secretion of GH and examined the effect of a short-acting and a long-acting GLP-1 RA on GH secretion.

METHODS

This is a post hoc analysis of data from clinical trials. Two separate single-group open-label clinical trials were carried out in the ambulatory care setting with a duration of 1 and 21 days, respectively. Healthy adult male and female volunteers with no chronic illnesses or use of daily medicines were recruited for the study. The two interventions were: study 1, single dose of 10 µg exenatide administered subcutaneously (s.c.); study 2, 0.6 mg liraglutide administered s.c. once daily for 21 days.

RESULTS

Administration of a single dose of exenatide (study 1) caused a clear increase in GH levels, peaking between 60 and 120 min post-administration. There was also a small but statistically significant decrease in luteinising hormone and testosterone levels 120 min after exenatide dosing. Administration of the long-acting GLP-1RA liraglutide daily for 21 days (study 2) elicited an increase in GH levels with no change in insulin-like growth factor-1 (IGF-1) concentrations after 3 weeks of treatment.

CONCLUSIONS

The results show that the administration of GLP-1RAs may elicit an increase in growth hormone levels. GLP-1 signalling may be a novel mechanism of regulation of GH secretion. This finding needs to be replicated in the placebo-controlled trial.

CLINICAL TRIAL REGISTRATION NUMBERS

NCT02089256 and NCT03160261.

Impact of Type 2 Diabetes Duration on the Efficacy and Safety of Add-on Lixisenatide in Asian Individuals Receiving Basal Insulin: A Pooled Analysis

INTRODUCTION

This analysis investigated the efficacy and safety of add-on lixisenatide by disease duration in Asian people with type 2 diabetes inadequately controlled with basal insulin ± oral antidiabetic drugs.

METHODS

Data for Asian participants in the GetGoal-Duo 1, GetGoal-L, and GetGoal-L-C studies were pooled and categorized by diabetes duration: < 10 years (group 1), 10 to < 15 years (group 2), and ≥ 15 years (group 3). Efficacy and safety of lixisenatide versus placebo were evaluated by subgroup. The potential influence of diabetes duration on efficacy was examined using multivariable regression analyses.

RESULTS

A total of 555 participants were included (mean age 53.9 years, 52.4% male). No significant differences in treatment effect between the duration subgroups were observed for the changes from baseline to 24 weeks in glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), postprandial glucose (PPG), PPG excursion, body weight or body mass index, or the proportion of participants with HbA1c < 7% at 24 weeks (all P values for interaction > 0.1). Change in insulin dosage (U/day) was significantly different between subgroups (P = 0.038). Multivariable regression analysis showed participants in group 1 had a smaller change in body weight and basal insulin dose over the 24-week treatment period than participants in group 3 (P = 0.014 and 0.030, respectively) and were less likely to achieve an HbA1c < 7% than participants in group 2 (P = 0.047). No severe hypoglycemia was reported. A higher proportion of participants in group 3 versus the other groups had symptomatic hypoglycemia, for both lixisenatide and placebo, and T2D duration had a significant effect on hypoglycemia risk (P = 0.001).

CONCLUSIONS

Lixisenatide improved glycemic control in Asian individuals regardless of diabetes duration, without increasing the risk of hypoglycemia. Individuals with longer disease duration had a greater risk of symptomatic hypoglycemia than individuals with shorter disease duration regardless of treatment. No additional safety concerns were observed.

CLINICAL TRIAL REGISTRATION

GetGoal-Duo 1, ClinicalTrials.gov record NCT00975286; GetGoal-L, ClinicalTrials.gov record NCT00715624; GetGoal-L-C, ClinicalTrials.gov record NCT01632163.

Glucagon-like peptide 1 receptor agonists and the potential risk of pancreatic carcinoma: a pharmacovigilance study using the FDA Adverse Event Reporting System and literature visualization analysis

BACKGROUND

There are increasing data on the potential risk of pancreatic carcinoma associated with glucagon-like peptide 1 receptor agonists (GLP-1RAs).

AIM

The study aimed to determine whether GLP-1RAs are associated with increased detection of pancreatic carcinoma based on the FDA Adverse Events Reporting System and clarify its potential mechanisms through keyword co-occurrence analysis from literature database.

METHOD

Disproportionality and Bayesian analyses were used for signal detection using reporting odds ratio (ROR), proportional reporting ratio (PRR), information component (IC), and empirical Bayesian geometric mean (EBGM). Mortality, life-threatening events, and hospitalizations were also investigated. VOSviewer was adopted to generate visual analysis of keyword hotspots.

RESULTS

A total of 3073 pancreatic carcinoma cases were related to GLP-1RAs. Five GLP-1RAs were detected with signals for pancreatic carcinoma. Liraglutide had the strongest signal detection (ROR 54.45, 95% CI 51.21-57.90; PRR 52.52, 95% CI 49.49-55.73; IC 5.59; EBGM 48.30). The signals of exenatide (ROR 37.32, 95% CI 35.47-39.28; PRR 36.45, 95% CI 34.67-38.32; IC 5.00; EBGM 32.10) and lixisenatide (ROR 37.07, 95% CI 9.09-151.09; PRR 36.09; 95% CI 9.20-141.64; IC 5.17, EBGM 36.09) were stronger than those of semaglutide (ROR 7.43, 95% CI 5.22-10.57; PRR 7.39; 95% CI 5.20-10.50; IC 2.88, EBGM 7.38) and dulaglutide (ROR 6.47, 95% CI 5.56-7.54; PRR 6.45; 95% CI 5.54-7.51; IC 2.67, EBGM 6.38). The highest mortality rate occurred in exenatide (63.6%). Based on the bibliometric investigation, cAMP/protein-kinase, Ca²⁺ channel, endoplasmic-reticulum stress, and oxidative stress are potential pathogenesis of pancreatic carcinoma resulting from GLP-1RAs.

CONCLUSION

Based on this pharmacovigilance study, GLP-1RAs, except albiglutide, are associated with pancreatic carcinoma.

Regulation of Pancreatic TXNIP-Insulin Expression Levels after Bariatric Surgery Using Diabetic Rodent Model

Purpose

The purpose of this study was to investigate the effect of bariatric surgery on pancreatic thioredoxin-interacting protein (TXNIP) and insulin expression levels. The research question is does bariatric surgery induce changes in the pancreatic TXNIP level, given that TXNIP has been proposed as a key glucose control factor?

Methods

Using nondiabetic and diabetic rats, we investigated whether our streptozotocin-induced diabetic rat models exhibited changes in pancreatic TXNIP regulation. Following this confirmation, we randomly divided the diabetic rats into the following three groups: the gastric bypass group (n = 16), pair-fed group (n = 10), and sham group (n = 10). Preoperatively and 3 weeks postoperatively, all the rats underwent an oral glucose tolerance test, insulin tolerance test, and blood sampling procedures for hormonal analysis.

Results

The TXNIP messenger ribonucleic acid (mRNA) and protein expression levels were significantly lower in the gastric bypass group than in the other groups. Regarding the gastric bypass group, the pancreatic mRNA expression levels of microRNA-204 (miR-204) and MafA were significantly lower and higher, respectively, than in the other groups. Furthermore, the levels of pancreatic insulin expression at the mRNA and protein levels were also significantly higher in the gastric bypass group than in the other groups.

Conclusion

Bariatric surgery significantly improved glucose control and regulated the pancreatic insulin production pathways of TXNIP, miR-204, and MafA. The regulation of TXNIP, miR-204, and MafA might play an important role in the mechanism of diabetes remission following bariatric surgery.

Commentary on Metabolic Health Disparities Affecting the Rio Grande Valley Mexican American Population: Seeking Answers Using Animal Models

Mexican Americans living in the Rio Grande Valley (RGV) have a high prevalence of type 2 diabetes (T2D). The US-Mexico border frontier has a unique blended culture of American lifestyle and Mexican traditions. Some examples of the cultural traditions are the food and the use of herbal medicine, but these traditions are in danger of disappearing after a very short number of generations living in the United States. This article describes the use of animal models under experimental conditions to solve practical questions (etiology or treatment). We performed studies with murine (ie, mouse and rat) models to elucidate the characteristics of medicinal plants that modulate glucose metabolism and inflammation and protect from bone loss, complications related to T2D. The University of Texas Rio Grande Valley researchers also have collaborated with the University of Texas Health Science Center at San Antonio researchers in performing studies in nonhuman primates (NHP) (ie, baboon) to understand the effect of T2D and diets on organs and tissues. With the new knowledge gained from the use of animal models (murine and NHP), new therapies are discovered for the prevention and treatment of T2D and its related complications, such as bone loss and nonalcoholic fatty liver disease, all of which the Mexican American and other human populations are at high risk of developing.

Incretin and insulin signaling as novel therapeutic targets for Alzheimer's and Parkinson's disease

Despite an ever-growing prevalence and increasing economic burden of Alzheimer's disease (AD) and Parkinson's disease (PD), recent advances in drug development have only resulted in minimally effective treatment. In AD, along with amyloid and tau phosphorylation, there is an associated increase in inflammation/glial activation, a decrease in synaptic function, an increase in astrocyte activation, and a state of insulin resistance. In PD, along with α-synuclein accumulation, there is associated inflammation, synaptic dysfunction, dopaminergic neuronal loss, and some data to suggest insulin resistance. Therapeutic strategies for neurodegenerative disorders have commonly targeted individual pathological processes. An effective treatment might require either utilization of multiple drugs which target the individual pathological processes which underlie the neurodegenerative disease or the use of a single agent which could influence multiple pathological processes. Insulin and incretins are compounds with multiple effects on neurodegenerative processes. Preclinical studies have demonstrated that GLP-1 receptor agonists reduce neuroinflammation, reduce tau phosphorylation, reduce amyloid deposition, increase synaptic function, and improve memory formation. Incretin mimetics may act through the restoration of insulin signaling pathways, inducing further neuroprotective effects. Currently, phase 2 and phase 3 trials are underway in AD and PD populations. Here, we provide a comprehensive review of the therapeutic potential of incretin mimetics and insulin in AD and PD.

Diabetes: Risk factor and translational therapeutic implications for Alzheimer's disease

Type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) commonly co-occur. T2DM increases the risk for AD by approximately twofold. Animal models provide one means of interrogating the relationship of T2DM to AD and investigating brain insulin resistance in the pathophysiology of AD. Animal models show that persistent hyperglycaemia results in chronic low-grade inflammation that may contribute to the development of neuroinflammation and accelerate the pathobiology of AD. Epidemiological studies suggest that patients with T2DM who received treatment with specific anti-diabetic agents have a decreased risk for the occurrence of AD and all-cause dementia. Agents such as metformin ameliorate T2DM and may have other important systemic effects that lower the risk of AD. Glucagon-like peptide 1 (GLP-1) agonists have been associated with a decreased risk for AD in patients with T2DM. Both insulin and non-insulin anti-diabetic treatments have been evaluated for the treatment of AD in clinical trials. In most cases, patients included in the trials have clinical features of AD but do not have T2DM. Many of the trials were conducted prior to the use of diagnostic biomarkers for AD. Trials have had a wide range of durations and population sizes. Many of the agents used to treat T2DM do not cross the blood brain barrier, and the effects are posited to occur via lowering of peripheral hyperglycaemia and reduction of peripheral and central inflammation. Clinical trials of anti-diabetic agents to treat AD are ongoing and will provide insight into the therapeutic utility of these agents.

A new era for oral peptides: SNAC and the development of oral semaglutide for the treatment of type 2 diabetes

Glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) were first introduced for the treatment of type 2 diabetes (T2D) in 2005. Despite the high efficacy and other benefits of GLP-1RAs, their uptake was initially limited by the fact that they could only be administered by injection. Semaglutide is a human GLP-1 analog that has been shown to significantly improve glycemic control and reduce body weight, in addition to improving cardiovascular outcomes, in patients with T2D. First approved as a once-weekly subcutaneous injection, semaglutide was considered an ideal peptide candidate for oral delivery with a permeation enhancer on account of its low molecular weight, long half-life, and high potency. An oral formulation of semaglutide was therefore developed by co-formulating semaglutide with sodium N-(8-[2-hydroxybenzoyl]amino)caprylate, a well-characterized transcellular permeation enhancer, to produce the first orally administered GLP-1RA. Pharmacokinetic analysis showed that stable steady-state concentrations could be achieved with once-daily dosing owing to the long half-life of oral semaglutide. Upper gastrointestinal disease and renal and hepatic impairment did not affect the pharmacokinetic profile. In the phase III PIONEER clinical trial program, oral semaglutide was shown to reduce glycated hemoglobin and body weight compared with placebo and active comparators in patients with T2D, with no new safety signals reported. Cardiovascular efficacy and safety are currently being assessed in a dedicated outcomes trial. The development of an oral GLP-1RA represents a significant milestone in the management of T2D, providing an additional efficacious treatment option for patients.

Pharmacologic Weight Management in the Era of Adolescent Obesity

CONTEXT

Pediatric obesity is a serious health problem in the United States. While lifestyle modification therapy with dietary changes and increased physical activity are integral for the prevention and treatment of mild to moderate obesity in youth, only a modest effect on sustained weight reduction is observed in children and young adults with severe obesity. This underscores the need for additional evidence-based interventions for children and adolescents with severe obesity, including pharmacotherapy, before considering invasive procedures such as bariatric surgery.

EVIDENCE ACQUISITION

This publication focuses on recent advances in pharmacotherapy of obesity with an emphasis on medications approved for common and rarer monogenic forms of pediatric obesity.

EVIDENCE SYNTHESIS

We review medications currently available in the United States, both those approved for weight reduction in children and "off-label" medications that have a broad safety margin.

CONCLUSION

It is intended that this review will provide guidance for practicing clinicians and will encourage future exploration for successful pharmacotherapy and other interventions for obesity in youth.

Eliminating exogenous insulin therapy in patients with type 2 diabetes by duodenal ablation and GLP-1RA decreases risk scores for cardiovascular events

Introduction

Duodenal Mucosal Resurfacing (DMR) is an endoscopic ablation technique aimed at improving glycaemia and metabolic health in patients with type 2 diabetes mellitus (T2DM). DMR has an insulin sensitizing effect in patients with T2DM. Reducing hyperinsulinemia can improve cardiovascular health. In the INSPIRE trial, we combined a single DMR with a glucagon-like-peptide-1 receptor agonist (GLP-1RA) and demonstrated elimination of insulin treatment in 69% of patients at 6 months and 53% of patients at 18 months while improving glycaemic control and metabolic health. We hypothesized that this treatment approach is associated with improved cardiovascular health, by reducing hyperinsulinemia.

Methods

Before and 6 months after starting the combination treatment to replace insulin, the following assessments were performed to evaluate cardiovascular health: magnetic resonance imaging (MRI) to measure abdominal visceral adipose tissue volume, ambulatory 24 h blood pressure (ABPM) analysis, postprandial insulin and triglycerides, fasting lipid panel and urine microalbumin. The Atherosclerotic Cardiovascular Disease (ASCVD) score was calculated to estimate 10-year risk of cardiovascular disease or stroke and the diabetes lifetime-perspective prediction (DIAL) score was calculated to estimate years free of cardiovascular disease.

Results

Six months after replacing exogenous insulin by DMR and GLP-1RA, visceral adipose tissue decreased significantly by 24%. Postprandial triglyceride and insulin concentrations decreased significantly (p < 0.001), as did total cholesterol (from median 3.64 (IQR 3.34–4.89) to 3.48 (3.18–3.97) mmol/l, p = 0.008), LDL (from median 1.92 (IQR 1.49–2.30) to 1.79 (1.49–2.08 mmol/l, p = 0.044), and urine microalbumin (from median 7 (IQR 3–27) to 4 (3–8) mg/l, p = 0.018). All daytime blood pressure values decreased significantly. The ASCVD 10-year risk score decreased (from median 13.6 (IQR 5.7–26.0) to 11.5 (4.2–22.5) %, p = 0.030)) and the DIAL score increased (from median 82 (IQR 81–83) to 83 (81–84) years, (p = 0.039)).

Discussion

The combination of DMR and GLP-1RA to replace insulin therapy in patients with T2DM is associated with a positive effect on multiple parameters of cardiovascular health. Taken together, they show a pattern of overall improvement in cardiovascular health, as evidenced by decreased risk scores for cardiovascular complications. However, it is not yet clear whether these improvements will translate into a true reduction in cardiovascular events.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01628-z.

Glucagon-like peptide 1 and fibroblast growth factor-21 in non-alcoholic steatohepatitis: An experimental to clinical perspective

Non-alcoholic steatohepatitis (NASH) is a progressive form of Non-alcoholic fatty liver disease (NAFLD), which slowly progresses toward cirrhosis and finally leads to the development of hepatocellular carcinoma. Obesity, insulin resistance, type 2 diabetes mellitus and the metabolic syndrome are major risk factors contributing to NAFLD. Targeting these risk factors is a rational option for inhibiting NASH progression. In addition, NASH could be treated with therapies that target the metabolic abnormalities causing disease pathogenesis (such as de novo lipogenesis and insulin resistance) as well with medications targeting downstream processes such as cellular damage, apoptosis, inflammation, and fibrosis. Glucagon-like peptide (GLP-1), is an incretin hormone dysregulated in both experimental and clinical NASH, which triggers many signaling pathways including fibroblast growth factor (FGF) that augments NASH pathogenesis. Growing evidence indicates that GLP-1 in concert with FGF-21 plays crucial roles in the conservation of glucose and lipid homeostasis in metabolic disorders. In line, GLP-1 stimulation improves hepatic ballooning, steatosis, and fibrosis in NASH. A recent clinical trial on NASH patients showed that the upregulation of FGF-21 decreases liver fibrosis and hepatic steatosis, thus improving the pathogenesis of NASH. Hence, therapeutic targeting of the GLP-1/FGF axis could be therapeutically beneficial for the remission of NASH. This review outlines the significance of the GLP-1/FGF-21 axis in experimental and clinical NASH and highlights the activity of modulators targeting this axis as potential salutary agents for the treatment of NASH.

Cardiovascular outcomes with GLP-1 receptor agonists vs. SGLT-2 inhibitors in patients with type 2 diabetes

AIMS

We examined cardiovascular outcomes associated with initiation of glucagon-like peptide-1 receptor agonist (GLP-1RA) vs. sodium-glucose co-transporter-2 inhibitor (SGLT-2i) treatment in a real-world setting among patients with type 2 diabetes.

METHODS AND RESULTS

This Danish nationwide registry-based cohort study included patients with type 2 diabetes with a first-ever prescription of either GLP-1RA or SGLT-2i from 2013 through 2015 with follow-up until end of 2018. All analyses were standardized with respect to age, sex, diabetes duration, comorbidity, and comedication. The main outcome was a composite of cardiovascular death, myocardial infarction, and stroke. Furthermore, the components of the composite outcome and hospitalization for heart failure were evaluated. Standardized average 3-year risks of outcomes and differences thereof were estimated using doubly robust estimation combining cause-specific Cox regression with propensity score regression. We identified 8913 new users of GLP-1RA and 5275 new users of SGLT-2i. The standardized 3-year risk associated with initiating GLP-1RA and SGLT-2i, respectively, was as follows: composite cardiovascular outcome, 5.6% [95% confidence interval (CI): 5.2-6.1] vs. 5.6% (95% CI: 4.8-6.3); cardiovascular mortality, 1.6% (95% CI: 1.3-1.9) vs. 1.5% (95% CI: 1.1-1.8); hospitalization for heart failure, 1.7% (95% CI: 1.5-2.0) vs. 1.8% (95% CI: 1.2-2.5); myocardial infarction, 2.1% (95% CI: 1.8-2.4) vs. 2.1% (95% CI: 1.5-2.6); and stroke, 2.5% (95% CI: 2.2-2.9) vs. 2.6% (95% CI: 2.2-3.1).

CONCLUSION

In this nationwide study of patients with type 2 diabetes, initiating GLP-1RA vs. SGLT-2i was not found to be associated with significant differences in cardiovascular risk.

Anti-Inflammatory Effects of GLP-1 Receptor Activation in the Brain in Neurodegenerative Diseases

The glucagon-like peptide-1 (GLP-1) is a pleiotropic hormone well known for its incretin effect in the glucose-dependent stimulation of insulin secretion. However, GLP-1 is also produced in the brain and displays a critical role in neuroprotection and inflammation by activating the GLP-1 receptor signaling pathways. Several studies in vivo and in vitro using preclinical models of neurodegenerative diseases show that GLP-1R activation has anti-inflammatory properties. This review explores the molecular mechanistic action of GLP-1 RAS in relation to inflammation in the brain. These findings update our knowledge of the potential benefits of GLP-1RAS actions in reducing the inflammatory response. These molecules emerge as a potential therapeutic tool in treating neurodegenerative diseases and neuroinflammatory pathologies.

Cardiovascular outcomes trials: a paradigm shift in the current management of type 2 diabetes

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity in patients with type 2 diabetes (T2D). Historical concerns about cardiovascular (CV) risks associated with certain glucose-lowering medications gave rise to the introduction of cardiovascular outcomes trials (CVOTs). Initially implemented to help monitor the CV safety of glucose-lowering drugs in patients with T2D, who either had established CVD or were at high risk of CVD, data that emerged from some of these trials started to show benefits. Alongside the anticipated CV safety of many of these agents, evidence for certain sodium-glucose transporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have revealed potential cardioprotective effects in patients with T2D who are at high risk of CVD events. Reductions in 3-point major adverse CV events (3P-MACE) and CV death have been noted in some of these CVOTs, with additional benefits including reduced risks of hospitalisation for heart failure, progression of renal disease, and all-cause mortality. These new data are leading to a paradigm shift in the current management of T2D, with international guidelines now prioritising SGLT2 inhibitors and/or GLP-1 RAs in certain patient populations. However, clinicians are faced with a large volume of CVOT data when seeking to use this evidence base to bring opportunities to improve CV, heart failure and renal outcomes, and even reduce mortality, in their patients with T2D. The aim of this review is to provide an in-depth summary of CVOT data-crystallising the key findings, from safety to efficacy-and to offer a practical perspective for physicians. Finally, we discuss the next steps for the post-CVOT era, with ongoing studies that may further transform clinical practice and improve outcomes for people with T2D, heart failure or renal disease.

Meta-analysis of cardiovascular outcome trials assessing the impact of glucagon-like peptide-1 receptor agonists on major cardiac arrhythmias

OBJECTIVE

Glucagon-like peptide-1 receptor agonists (GLP-1RAs), a group of novel antidiabetic agents, demonstrated beneficial cardiovascular effects in recent large, placebo-controlled randomised clinical trials (RCTs); their clear antiarrhythmic benefit has not been yet underlined. The purpose of the present meta-analysis is to clarify the impact of GLP-1RAs on different types of cardiac arrhythmias.

METHODS

We searched PubMed from its inception up to 8 October 2020 for all available cardiovascular and renal outcome, placebo-controlled RCTs utilising GLP-1RAs versus placebo. The present meta-analysis is reported according to the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) statement.

RESULTS

We included data from 7 RCTs with GLP-1RAs in a total of 55,943 participants. Treatment with GLP-1RAs did not provide significant benefit in the risk for atrial fibrillation (RR = 0.81, 95%CI; 0.78-1.15, I² = 51%), atrial flutter (RR = 0.79, 95%CI; 0.53-1.16, I² = 0%), ventricular fibrillation (RR = 0.99, 95%CI; 0.48-2.04, I² = 0%), ventricular tachycardia (RR = 1.41, 95%CI; 0.87-2.28, I² = 10%), atrial tachycardia (RR = 0.63, 95%CI; 0.10-3.90, I² = 24%), sinus node dysfunction (RR = 0.70, 95%CI; 0.40-1.23, I² = 0%), ventricular extrasystoles (RR = 1.37, 95%CI; 0.56-3.30, I² = 0%), second-degree atrioventricular block (RR = 0.96, 95%CI; 0.52-1.74, I² = 0%) or complete atrioventricular block (RR = 0.78, 95%CI; 0.39-1.54, I² = 38%).

CONCLUSIONS

In patients with type 2 diabetes mellitus, treatment with GLP-1RAs does not significantly affect the risk for major cardiac arrhythmias.

Effects of glucagon-like peptide-1 receptor agonists on cardiovascular and renal outcomes: A meta-analysis and meta-regression analysis

AIM

To evaluate the cardiovascular and renal outcomes of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and the associations between these outcomes and HbA1c or weight reduction.

MATERIALS AND METHODS

We searched PubMed/MEDLINE, EMBASE, and CENTRAL databases for randomized, placebo-controlled trials of GLP-1 RAs reporting major adverse cardiovascular events (MACE; a composite of cardiovascular mortality, stroke, and myocardial infarction) as the primary outcome. We conducted a meta-regression analysis of primary and secondary outcomes with HbA1c or weight reduction following a meta-analysis with a random-effects model for these outcomes.

RESULTS

We extracted data of 60 800 individuals from eight eligible studies (ELIXA, LEADER, SUSTAIN-6, EXSCEL, HARMONY, PIONEER 6, REWIND, and AMPLITUDE-O). GLP-1 RAs reduced MACE (hazard ratio [HR] 0.86; 95% CI: 0.80-0.93; P < .001) and secondary outcomes including the composite renal outcome (0.80; 0.73-0.87; P < .001). In meta-regression analysis, every 1% reduction in HbA1c was associated with 26% and 35% decreases in the logarithm of HR of MACE (P = .044; R²  = 0.65) and the composite renal outcome (P = .040; R²  = 0.85), respectively. On the contrary, weight reduction was not associated with any outcome, including MACE (P = .390).

CONCLUSIONS

The reduction in HbA1c, but not body weight, is associated with cardiovascular and renal outcomes. The magnitude of HbA1c reduction can be a surrogate for the cardiovascular and renal benefits of treatment with GLP-1 RAs.

Effect of glucagon-like peptide-1 receptor agonists on body weight in adults with obesity without diabetes mellitus-a systematic review and meta-analysis of randomized control trials

Clinical trials have investigated the weight loss effect of glucagon-like peptide-1 receptor agonists (GLP-1 RA) in adults with obesity without diabetes mellitus, but results for weight loss efficacy were varied. We aimed to provide an up-to-date systematic review and meta-analysis for overall weight loss effect of GLP-1 RA in adults with obesity and overweight without diabetes mellitus. We retrieved eligible randomized control trials that assessed the weight loss effect of GLP-1 RA in adults (≥18 years old) without type 1/type 2 diabetes up to September 30, 2021, using Pubmed and Embase. Of 36 clinical trials assessed for eligibility, 12 trials were included, with a combined total of 11,459 participants. Compared with control groups, a more significant weight loss was seen in GLP-1 RA groups with an overall mean difference of -7.1 kg (95% CI -9.2 to -5.0) (I²  = 99%). The overall analysis results showed that GLP-1 RA improved glycemic control without increasing the risk of hypoglycemic events. Better control of blood pressure and plasma levels of LDL, HDL, and triglycerides was seen with GLP-1 RA treatment. Subgroup analysis showed greater treatment effect of semaglutide than liraglutide. Vomiting, nausea, dyspepsia, diarrhea, constipation, and abdominal pain were GLP-1 RA-associated common adverse effects.

Glucagon-Like Peptide 1 Receptor Agonists: A Medication for Obesity Management

PURPOSE OF REVIEW

The burden of obesity worldwide is high and projected to rise. Obesity increases the risk of several cardiovascular diseases and cardiometabolic risk factors; hence, utilizing effective long-term therapies for obesity is of utmost importance. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have emerged as effective therapies that achieve substantial weight loss and improve cardiometabolic risk. The purpose of this review is to discuss the role of GLP-1RAs in obesity management.

RECENT FINDINGS

Two subcutaneous GLP-1RAs, liraglutide and semaglutide, have been evaluated in several clinical trials for weight loss. Liraglutide achieves a mean weight loss of 4-7 kg, and more than 50% of treated individuals achieve 5% or more weight loss. Semaglutide has a greater impact on weight loss, with a mean weight loss of 9-16 kg, and more than 50% of treated individuals achieve 10-15% or more weight loss. These results led to regulatory approval of these agents for weight loss in individuals with obesity, regardless of diabetes status. In addition to weight loss, the benefits of GLP-1RAs extend to other risk factors, such as glycemic control and blood pressure. Gastrointestinal symptoms are the most frequently encountered adverse events with incidences between 5 and 30%. Finally, the cost remains one of the most critical challenges that limit GLP-1RAs use. GLP-1RAs have robust weight loss benefits and are expected to have a critical role in the management of obesity in the coming years. Upcoming studies will evaluate the durability of weight loss achieved with GLP-1RAs and the impact on cardiovascular outcomes.

Gut-Brain Communication in Parkinson's Disease: Enteroendocrine Regulation by GLP-1

PURPOSE OF REVIEW

Defective gut-brain communication has recently been proposed as a promoter of neurodegeneration, but mechanisms mediating communication remain elusive. In particular, the Parkinson's disease (PD) phenotype has been associated with both dysbiosis of intestinal microbiota and neuroinflammation. Here, we review recent advances in the PD field that connect these two concepts, providing an explanation based on enteroendocrine signaling from the gut to the brain.

RECENT FINDINGS

There have been several recent accounts highlighting the importance of the microbiota-gut-brain axis in PD. The objective of this review is to discuss the role of the neuroendocrine system in gut-brain communication as it relates to PD pathogenesis, as this system has not been comprehensively considered in prior reviews. The incretin hormone glucagon-like peptide 1 (GLP-1) is secreted by enteroendocrine cells of the intestinal epithelium, and there is evidence that it is neuroprotective in animal models and human subjects with PD. Agonists of GLP-1 receptors used in diabetes appear to be useful for preventing neurodegeneration. New tools and models have enabled us to study regulation of GLP-1 secretion by intestinal microbiota, to understand how this process may be defective in PD, and to develop methods for therapeutically modifying disease development or progression using the enteroendocrine system. GLP-1 secretion by enteroendocrine cells may be a key mediator of neuroprotection in PD, and new findings in this field may offer unique insights into PD pathogenesis and therapeutic strategies.