The value of short- and long-acting glucagon-like peptide-1 agonists in the management of type 2 diabetes mellitus: experience with exenatide

Mortality and cardiovascular events in diabetes mellitus patients at dialysis initiation treated with glucagon-like peptide-1 receptor agonists

BACKGROUND

Glucagon-like Peptide-1 Receptor Agonists (GLP-1RAs) have demonstrated efficacy in improving mortality and cardiovascular (CV) outcomes. However, the impact of GLP-1RAs therapy on cardiorenal outcomes of diabetic patients at the commencement of dialysis remains unexplored.

PURPOSE

This study aimed to investigate the long-term benefits of GLP-1RAs in type 2 diabetic patients at dialysis commencement.

METHODS

A cohort of type 2 diabetic patients initializing dialysis was identified from the TriNetX global database. Patients treated with GLP-1RAs and those treated with long-acting insulin (LAI) were matched by propensity score. We focused on all-cause mortality, four-point major adverse cardiovascular events (4p-MACE), and major adverse kidney events (MAKE).

RESULTS

Among 82,041 type 2 diabetic patients initializing dialysis, 2.1% (n = 1685) patients were GLP-1RAs users (mean ages 59.3 years; 55.4% male). 1682 patients were included in the propensity-matched group, treated either with GLP-1RAs or LAI. The main causes of acute dialysis in this study were ischemic heart disease (17.2%), followed by heart failure (13.6%) and sepsis (6.5%). Following a median follow-up of 1.4 years, GLP-1RAs uses at dialysis commencement was associated with a reduced risk of mortality (hazard ratio [HR] = 0.63, p < 0.001), 4p-MACE (HR = 0.65, p < 0.001), and MAKE (HR = 0.75, p < 0.001). This association was particularly notable in long-acting GLP-1RAs users, with higher BMI, lower HbA1c, and those with eGFR > 15 ml/min/1.73m2. GLP-1RAs' new use at dialysis commencement was significantly associated with a lower risk of MACE (p = 0.047) and MAKE (p = 0.004). Additionally, GLP-1RAs use among those who could discontinue from acute dialysis or long-term RAs users was associated with a lower risk of mortality, 4p-MACE, and MAKE.

CONCLUSION

Given to the limitations of this observational study, use of GLP-1RAs at the onset of dialysis was associated with a decreased risk of MACE, MAKE, and all-cause mortality. These findings show the lack of harm associated with the use of GLP-1RAs in diabetic patients at the initiation of acute dialysis.

GLP-1 receptor agonists' impact on cardio-renal outcomes and mortality in T2D with acute kidney disease

Previous studies have explored the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in reducing cardiovascular events in type 2 diabetes. Here we show that GLP-1 RAs are associated with lower risks of mortality, major cardiovascular events (MACEs), and major adverse kidney events (MAKEs) in type 2 diabetes patients with acute kidney disease (AKD). Utilizing global data from the TriNetX database (2002/09/01-2022/12/01) and propensity score matching, we compare 7511 GLP-1 RAs users to non-users among 165,860 AKD patients. The most common causes of AKI are sepsis (55.2%) and cardiorenal syndrome (34.2%). After a median follow-up of 2.3 years, GLP-1 RAs users exhibit reduced risks of mortality (adjusted hazard ratio [aHR]: 0.57), MACEs (aHR: 0.88), and MAKEs (aHR: 0.73). External validation in a multicenter dataset of 1245 type 2 diabetes patients with AKD supports the favorable outcomes. These results emphasize the potential of GLP-1 RAs in individualized treatment for this population.

Exenatide for obesity in children and adolescents: Systematic review and meta-analysis

Objectives: There is no curative treatment for childhood obesity. We aim to synthesize published Randomized Controlled Trials (RCTs) evidence on the efficacy of exenatide in obese children and adolescents. Methods: We conducted a comprehensive search and analysis of relevant studies in popular databases such as PubMed, Web of Science, Embase, and Cochrane Library. Our focus was on RCTs that examined the effectiveness of exenatide for treating obesity in children. We primarily assessed changes in body weight, body mass index (BMI), fasting plasma glucose (FPG), or HbA1c levels. Additionally, we considered any adverse events reported during the treatment period, with particular attention to hypoglycemia. To evaluate the quality of RCTs included in our study, we employed the Cochrane bias assessment tool. Results: Five studies met the inclusion criteria. A group of 100 children were assigned to receive treatment with exenatide. Compared with controls, exenatide therapy reduced body weight and BMI by -0.6% (95% CI -0.93, -0.27), -1.11% (95% CI -1.91, -0.31), respectively. Undesirable consequences encompass gastrointestinal symptoms, with the majority of instances being characterized by mild severity. Conclusion: Exenatide demonstrates efficacy in the treatment of pediatric and adolescent obesity. Systematic Review Registration: PROSPERO https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=413706.

PEGylated exenatide injection (PB-119) improves beta-cell function and insulin resistance in treatment-naïve type 2 diabetes mellitus patients

Objective: PB-119, a PEGylated exenatide injection, is a once-weekly glucagon-like peptide-1 receptor agonist. In the present study, we aimed to evaluate the effects of PB-119 on insulin resistance and beta-cell function in Chinese patients with type 2 diabetes mellitus (T2DM) to uncover its antidiabetic characteristics. Methods: A total of 36 Chinese T2DM patients were randomized to receive 25 μg and 50 μg PB-119 once weekly and exenatide (5-10 μg injected under the skin 2 times a day adjusted by the doctor) for 12 weeks. Oral mixed meal tolerance tests were conducted before the study and on Day 79. The data were fitted to estimate beta-cell function and insulin sensitivity parameters using the SAAM II package integrating the oral minimal model (OMM), which was compared with Homeostatic Model Assessment (HOMA) analysis results. Results: Exenatide or PB-119 treatment, compared with their baseline, was associated with higher beta-cell function parameters (φb, φs and φtot), disposition index, insulin secretion rates, and a lower glucose area under the curve. High-dose PB-119 also has a higher insulin resistance parameter (SI) than the baseline, but HOMA-IR did not. For the homeostatic model assessment parameters, HOMA-IR showed no statistically significant changes within or between treatments. Only high-dose PB-119 improved HOMA-β after 12 weeks of treatment. Conclusion: After 12 weeks of treatment, PB-119 decreased glycemic levels by improving beta-cell function and insulin resistance.

Expression of glucagon-like peptide 1 receptor in neuropeptide Y neurons of the arcuate nucleus in mice

Glucagon-like peptide 1 (GLP-1) and its agonists exert anorexigenic effect at least partly via acting on GLP-1 receptors (GLP-1R) in the arcuate nucleus (ARC). While the anorexigenic, proopiomelanocortin (POMC) neurons of the ARC were shown previously to express GLP-1R, the putative GLP-1R-content of the orexigenic, neuropeptide Y (NPY) neurons remained so far undetected. As GLP-1R is abundant in the ventromedial ARC, where NPY neurons are located; here, we address the possibility that GLP-1 can act directly on the orexigenic NPY system via GLP-1R. Double-labeling immunocytochemistry and in situ hybridization were performed on tissues of adult male mice to detect GLP-1R in NPY neurons. In double-immunolabeled preparations, GLP-1R-immunoreactivity was observed in NPY neurons and in axons ensheathing the majority of NPY neurons. Ultrastructural studies confirmed that GLP-1R-immunoreactivity is associated with the outer membrane of NPY perikarya as well as with axons forming symmetric type, inhibitory synapses on NPY-containing neurons. Double-labeling in situ hybridization experiments demonstrated the expression of GLP-1R mRNA in approximately 20% of NPY mRNA-containing neurons of the ARC. In summary, our data demonstrate the presence of GLP-1R protein and mRNA in NPY neurons of ARC and also reveal the innervation of NPY neurons by GLP-1R-containing inhibitory neurons. These observations suggest that GLP-1 signaling can influence NPY neurons both directly and indirectly. Furthermore, GLP-1 signaling on energy homeostasis appears to involve both direct and indirect effects of GLP-1 on the orexigenic NPY neurons, in addition to the previously known effects via the anorexigenic POMC neuronal system.

Liraglutide Protects Nucleus Pulposus Cells Against High-Glucose Induced Apoptosis by Activating PI3K/Akt/ mTOR/Caspase-3 and PI3K/Akt/GSK3β/Caspase-3 Signaling Pathways

Background and Objective: Diabetes mellitus (DM) is reportedly a significant risk factor for intervertebral disc degeneration (IDD). Incretin system and particularly glucagon-like peptide 1 (GLP-1) because of its glucose-lowering effects has become an important target in therapeutic strategies of type 2 diabetes (T2D). Liraglutide is a GLP-1 receptor (GLP-1R) agonist with glucoregulatory and insulinotropic functions as well as regulatory functions on cell proliferation, differentiation, and apoptosis. However, little is known on the roles and signaling pathways of apoptosis protecting effects of liraglutide in IDD. This study aimed to investigate the potential protective effects of liraglutide against high glucose-induced apoptosis of nucleus pulposus cells (NPCs) and the possible involved signaling pathways.

Methods: The human NPCs were incubated with 100 nM liraglutide alone or in combination with LY294002 (PI3K inhibitor), rapamycin (mTOR inhibitor), and SB216763 (GSK3β inhibitor) in a high glucose culture for 48 h. The four groups were assessed further for apoptosis and genes expressions. The apoptotic effect was evaluated by flow cytometry and further confirmed by cell death detection enzyme-linked immunoassay plus (ELISAPLUS). The gene and protein expression levels were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting techniques. The results were comparatively assessed between the four groups.

Results: The results confirmed the presence of GLP-1R in the NPCs indicating that liraglutide inhibited the high glucose-induced apoptosis, which was blocked by silencing GLP-1R with siRNA. Moreover, liraglutide stimulated the phosphorylation of Akt, mTOR and GSK3β. Treatment with LY294002 significantly increased the apoptosis of NPCs and reduced the levels of their downstream substrates (p-AKT, p-mTOR, and p-GSK3β). Further assessments revealed that activation of mTOR and GSK3β was almost completely inhibited by rapamycin and SB216763, respectively, which significantly increased the caspase-3 levels.

Conclusion: Liraglutide could protect NPCs against high glucose-induced apoptosis by activating the PI3K/AKT/mTOR/caspase-3 and PI3K/AKT/GSK3β/caspase-3 signaling pathways.

Everestmab, a novel long-acting GLP-1/anti GLP-1R nanobody fusion protein, exerts potent anti-diabetic effects

In the present study, a novel single domain antibody (sdAb) fusion protein, named everestmab, composing of a mutated GLP-1(A8G) fused to the tandem bispecific humanized GLP-1R-targeting and albumin-binding nanobodies was designed and characterized for the therapies for type 2 diabetes mellitus (T2DM). Surface plasmon resonance (SPR) measurements demonstrated everestmab associates with serum albumins of rat and monkey species with high affinity, and tends to be cross-reactive with rat and monkey species. In vitro GLP-1R binding and activation assays revealed that everestmab can specifically activate the GLP-1R, and the antagonist exendin-4 (9-39) did not inhibit the activation yet. In vivo multiple oral glucose tolerance tests (OGTTs) and hypoglycaemic efficacy tests proved that a single injection of everestmab reduced the blood glucose for at least 144 h in Goto-Kakizaki (GK) rats. The plasma half-lives of 4.1 and 7.8 days were observed after a single s.c. administration of everestmab in SD rats and cynomolgus monkeys, respectively. Chronic treatment of everestmab to GK and diet induced obese (DIO) rats achieved beneficial effects on weight reducing, HbA1c lowering, glucose tolerance, liver and pancreas islet function impairment. In summary, everestmab is a unique G-protein-coupled receptor-targeted nanobody fusion protein and exerts potential as a therapeutic treatment for T2DM.

Impact of disease duration and β-cell reserve on the efficacy of switching to iGlarLixi in adults with type 2 diabetes on glucagon-like peptide-1 receptor agonist therapy: Exploratory analyses from the LixiLan-G trial

AIM

To evaluate the efficacy of iGlarLixi by C-peptide levels and duration of diabetes in an exploratory analysis of the LixiLan-G study.

METHODS

LixiLan-G was a 26-week, randomized, open-label study in adults with type diabetes (T2D) inadequately controlled while on a glucagon-like peptide-1 receptor agonist (GLP-1 RA), with metformin, with or without pioglitazone and/or a sodium-glucose co-transporter-2 inhibitor. This analysis investigated the efficacy of switching to iGlarLixi by fasting baseline quartile C-peptide levels and baseline quartile of duration of T2D compared with continued GLP-1 RA use.

RESULTS

Change in glycated hemoglobin (HbA1c) from baseline to week 26 was significantly greater with iGlarLixi compared with continued GLP-1 RAs across all fasting C-peptide quartiles (-1.00% to -1.06% vs. -0.23% to -0.54% range, respectively) and irrespective of all T2D duration quartiles (-0.94% to -1.07% vs. -0.25% to -0.50% range). A significantly greater proportion of participants in the iGlarLixi arm achieved an HbA1c of <7% across all C-peptide quartiles (51%-73% range) than in the GLP-1 RA arm (19%-32% range). The greatest reductions in HbA1c in participants receiving iGlarLixi were observed in those with the shortest duration of disease, although consistently greater than reductions observed with continued GLP-1 RAs. Reductions in HbA1c were comparable across C-peptide quartiles within the iGlarLixi arm.

CONCLUSIONS

The results of this study suggest that iGlarLixi is an effective treatment option, irrespective of C-peptide levels or duration of diabetes, in adults with insufficiently controlled T2D receiving GLP-1 RAs.

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

WHAT IS KNOWN AND OBJECTIVE

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

METHODS

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

RESULTS AND DISCUSSION

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

WHAT IS NEW AND CONCLUSION

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

Beta-cell failure in type 2 diabetes: mechanisms, markers, and clinical implications

It is well known that type 2 diabetes mellitus (T2D) is a globally increasing health burden. Despite recent therapeutic advances and the availability of many different classes of antihyperglycemic therapy, a large proportion of people do not achieve glycemic control. A decline in pancreatic beta-cell function has been defined as a key contributing factor to progression of T2D. In fact, a significant proportion of beta-cell secretory capacity is thought to be lost well before the diagnosis of T2D is made. Several models have been proposed to explain the reduction in beta-cell function, including reduced beta-cell number, beta-cell exhaustion, and dedifferentiation or transdifferentiation into other cell types. However, there have been reports that suggest remission of T2D is possible, and it is believed that beta-cell dysfunction may be, in part, reversible. As such, the question of whether beta cells are committed to failure in people with T2D is complex. It is now widely accepted that early restoration of normoglycemia may protect beta-cell function. Key to the successful implementation of this approach in clinical practice is the appropriate assessment of individuals at risk of beta-cell failure, and the early implementation of appropriate treatment options. In this review, we discuss the progression of T2D in the context of beta-cell failure and describe how C-peptide testing can be used to assess beta-cell function in primary care practice. In conclusion, significant beta-cell dysfunction is likely in individuals with certain clinical characteristics of T2D, such as long duration of disease, high glycated hemoglobin (≥9%), and/or long-term use of therapies that continuously stimulate the beta cell. In these people, measurement of beta-cell status could assist with choice of appropriate therapy to delay or potentially reverse beta-cell dysfunction and the progression of T2D.

GLP-1 receptor agonists synergize with DYRK1A inhibitors to potentiate functional human β cell regeneration

Glucagon-like peptide-1 receptor (GLP1R) agonists and dipeptidyl peptidase 4 inhibitors are widely prescribed diabetes drugs due to their ability to stimulate insulin secretion from remaining β cells and to reduce caloric intake. Unfortunately, they fail to increase human β cell proliferation. Small-molecule inhibitors of dual-specificity tyrosine-regulated kinase 1A (DYRK1A) are able to induce adult human β cell proliferation, but rates are modest (~2%), and their specificity to β cells is limited. Here, we provide evidence that combining any member of the GLP1R agonist class with any member of the DYRK1A inhibitor class induces a synergistic increase in human β cell replication (5 to 6%) accompanied by an actual increase in numbers of human β cells. GLP1R agonist-DYRK1A inhibitor synergy required combined inhibition of DYRK1A and an increase in cAMP and did not lead to β cell dedifferentiation. These beneficial effects on proliferation were seen in both normal human β cells and β cells derived from individuals with type 2 diabetes. The ability of the GLP1R agonist-DYRK1A inhibitor combination to enhance human β cell proliferation, human insulin secretion, and blood glucose control extended in vivo to studies of human islets transplanted into euglycemic and streptozotocin-diabetic immunodeficient mice. No adverse events were observed in the mouse studies during a 1-week period. Because of the relative β cell specificity of GLP1R agonists, the combination provides an improved, although not complete, degree of human β cell specificity.

Comparison of ELISA and HPLC-MS methods for the determination of exenatide in biological and biotechnology-based formulation matrices

The development of biotechnology-based active pharmaceutical ingredients, such as GLP-1 analogs, brought changes in type 2 diabetes treatment options. For better therapeutic efficiency, these active pharmaceutical ingredients require appropriate administration, without the development of adverse effects or toxicity. Therefore, it is required to develop several quantification methods for GLP-1 analogs products, in order to achieve the therapeutic goals, among which ELISA and HPLC arise. These methods are developed, optimized and validated in order to determine GLP-1 analogs, not only in final formulation of the active pharmaceutical ingredient, but also during preclinical and clinical trials assessment. This review highlights the role of ELISA and HPLC methods that have been used during the assessment for GLP-1 analogs, especially for exenatide.

Utilization patterns of glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes mellitus in Germany: a retrospective cohort study

OBJECTIVE

This retrospective database analysis complements previous research to understand treatment patterns for German patients newly-initiating or switching to subsequent GLP-1 RAs.

METHODS

Adult patients (≥18 years) initiating GLP-1 RA (Cohort 1 [C1]) or switching from a previous GLP-1 RA (Cohort 2 [C2]) to exenatide twice-daily (exBID), exenatide once-weekly (exQW), dulaglutide (DULA), or liraglutide (LIRA) were included in this analysis using IQVIA LRx from January 1, 2014-March 31, 2017. Patients were required to have ≥1 oral anti-hyperglycemic prescription during the 6-month pre-index period and ≥12 months follow-up. Persistence and treatment modifications were assessed within and beyond 12 months follow-up. Average daily/weekly dosage (ADD/AWD) was calculated during persistence.

RESULTS

C1 included 13,417 patients, while C2 included 4,264 patients. Mean ± standard deviation (SD) age was similar (57.7 ± 11.1 years [C1], 58.9 ± 10.1 years [C2]). Most patients using DULA in C2 had switched from LIRA (56.6%). For C1, mean ADD for LIRA was 1.41 ± 0.10 mg, slightly higher in C2, and increased over time. ADD for exBID was 16.9 ± 1.0 mcg, slightly greater in C2. AWD was 2.00 ± 0.05 mg for exQW users and 1.42 ± 0.03 mg for DULA users in C1, similar to C2. For C1, 27.0% exBID, 35.3% exQW, 50.9% DULA, and 48.1% LIRA users remained persistent at 12 months. Patients using DULA had a higher probability of remaining persistent over time (Kaplan-Meier) for both cohorts.

CONCLUSIONS

Patients using DULA had the highest probability of remaining persistent over time, followed by LIRA. ADD/AWD for DULA, exQW, and exBID were aligned with the recommended combination therapy dose; LIRA ADD suggests some patients use the 1.8 mg dose.

The Role of Glucagon-Like Peptide-1 Receptor Agonists in Type 2 Diabetes in Asia

The improvement of glycemic control in patients with type 2 diabetes (T2D) is an urgent need in Asia. East Asian T2D patients have distinct characteristics, including relatively low body weight, early impairment of islet beta cell function with reduced insulin secretion and a marked increase in postprandial blood glucose levels. Control of postprandial hyperglycemia and beta cell preservation are key elements of the therapeutic strategy for these patients. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) reduce HbA1c, fasting plasma glucose, and (in particular) postprandial glucose levels, and slow gastric emptying, while minimizing the risk of hypoglycemia and weight gain. Compared with long-acting GLP-1RAs, short-acting GLP-1RAs produce greater slowing of gastric emptying (which is a key factor driving the reduction of postprandial glycemia) and induce beta cell rest rather than promoting postprandial insulin secretion when used under physiological conditions. GLP-1RAs have greater efficacy in Asian than Caucasian patients. GLP-1RA add-on therapy provides clinically meaningful reductions in HbA1c and postprandial glucose in Asians with T2D inadequately controlled by oral antidiabetic drugs (OADs) or basal insulin ± OADs. Premixed insulin is often prescribed for T2D patients in China. A short-acting GLP-1RA plus basal insulin is an alternative to premixed insulin, resulting in better efficacy and a lower risk of hypoglycemia and weight gain. In conclusion, GLP-1RAs, especially short-acting GLP-1RAs, are a practical treatment option for East Asian patients with T2D inadequately controlled by OADs or basal insulin.Funding: Sanofi.

Structural Modeling and in Silico Screening of Potential Small-Molecule Allosteric Agonists of a Glucagon-like Peptide 1 Receptor

The glucagon-like peptide 1 receptor (GLP-1R) belongs to the pharmaceutically important class B family of G-protein-coupled receptors (GPCRs), and its incretin peptide ligand GLP-1 analogs are adopted drugs for the treatment of type 2 diabetes. Despite remarkable antidiabetic effects, GLP-1 peptide-based drugs are limited by the need of injection. On the other hand, developing nonpeptidic small-molecule drugs targeting GLP-1R remains elusive. Here, we first constructed a three-dimensional structure model of the transmembrane (TM) domain of human GLP-1R using homology modeling and conformational sampling techniques. Next, a potential allosteric binding site on the TM domain was predicted computationally. In silico screening of druglike compounds against this predicted allosteric site has identified nine compounds as potential GLP-1R agonists. The independent agonistic activity of two compounds was subsequently confirmed using a cAMP response element-based luciferase reporting system. One compound was also shown to stimulate insulin secretion through in vitro assay. In addition, this compound synergized with GLP-1 to activate human GLP-1R. These results demonstrated that allosteric regulation potentially exists in GLP-1R and can be exploited for developing small-molecule agonists. The success of this work will help pave the way for small-molecule drug discovery targeting other class B GPCRs through allosteric regulations.

Introduction

This supplement was funded by Novo Nordisk. McGill has received grants and personal fees from Novo Nordisk; grants from AstraZeneca, Novartis, Lexicon, and Pfizer; and personal fees from Intarcia, Boehringer-Ingelheim, Janssen, Mannkind, Bayer, and Merck.

Glycemic Efficacy, Weight Effects, and Safety of Once-Weekly Glucagon-Like Peptide-1 Receptor Agonists

This article provides an overview of the efficacy and safety of once-weekly glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in the treatment of type 2 diabetes mellitus (T2DM). GLP-1 RAs stimulate pancreatic GLP-1 receptors, which increases insulin secretion, delays gastric emptying, and increases satiety. As a class, GLP-1 RAs lower A1c levels and have been associated with reductions in weight and blood pressure and reduced fluctuations in glucose levels, and they have a low risk of hypoglycemia. Exenatide extended release (ER) and dulaglutide monotherapy have shown similar or superior reductions in A1c and weight compared with various oral antidiabetic drugs (OADs). Semaglutide has been shown to reduce both A1c and body weight compared with placebo and, in head-to-head studies versus both exenatide ER and dulaglutide, showed greater reductions in A1c and body weight. Once-weekly GLP-1 RAs have also been evaluated as add-on therapy in the continuum of care for the treatment of T2DM in combination with a variety of background medications, including 1 or more OADs (metformin, sulfonylureas, and/or thiazolidinediones), basal insulin, and prandial insulin. Gastrointestinal adverse events (e.g., nausea, vomiting, and diarrhea) are the most common side effects with once-weekly GLP-1 RAs. Rates of hypoglycemia, and especially major/severe hypoglycemia, are low with once-weekly GLP-1 RAs but, as expected, are higher when used in combination with sulfonylureas or insulin. These once-weekly GLP-1 RAs provide a safe and effective treatment option for patients with T2DM and may offer improved convenience and possibly greater adherence compared with daily GLP-1 RAs.

DISCLOSURES

This supplement was funded by Novo Nordisk. Handelsman reports research grants from Amgen, AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Grifols, Janssen, Lexicon, Merck, Novo Nordisk, Regeneron, and Sanofi; speaker fees from Amarin, Amgen, AstraZeneca, Boehringer Ingelheim-Lilly, Janssen, Merck, Novo Nordisk, Regeneron, and Sanofi; and has served in advisory capacity to Amarin, Amgen, AstraZeneca, Boehringer Ingelheim, Eisai, Intarcia, Janssen, Lilly, Merck, Merck-Pfizer, Novo Nordisk, Regeneron, and Sanofi. Cannon reports speaker fees and owns stock in Novo Nordisk. Shannon reports consultant and speaker fees from Novo Nordisk and Boehringer Ingelheim-Lilly Alliance. Schneider reports advisory board fees from Intarcia, Lilly, and Novo Nordisk. Wyne has nothing to disclose.

Adherence to antihyperglycemic medications and glucagon-like peptide 1-receptor agonists in type 2 diabetes: clinical consequences and strategies for improvement

Adherence to antihyperglycemic medications is often suboptimal in patients with type 2 diabetes, and this can contribute to poor glycemic control, increased hospitalization, and the development of diabetic complications. Reported adherence rates to antihyperglycemics vary widely among studies, and this may be related to differences in methodology for measuring adherence, patient populations, and other factors. Poor adherence may occur regardless of the specific regimen used and whether therapy is oral or injectable, and can be especially common in chronic, asymptomatic conditions, such as type 2 diabetes. More convenient drug-administration regimens and advances in formulations and delivery devices are among strategies shown to improve adherence to antihyperglycemic therapy, especially for injectable therapy. This is exemplified by technological developments made in the drug class of glucagon-like peptide 1-receptor agonists, which are a focus of this narrative review. Dulaglutide, albiglutide, and prolonged-release exenatide have an extended duration of action and can be administered once weekly, whereas such agents as liraglutide require once-daily administration. The convenience of once-weekly versus once-daily administration is associated with better adherence in real-world studies involving this class of agent. Moreover, provision of a user-friendly delivery device has been shown to overcome initial resistance to injectable therapy among patients with type 2 diabetes. This suggests that recent innovations in drug formulation (eg, ready-to-use formulations) and delivery systems (eg, single-dose prefilled pens and hidden, ready-attached needles) may be instrumental in encouraging patient acceptance. For physicians who aim to improve their patients' adherence to antihyperglycemic medications, it is thus important to consider the patient's therapeutic experience (treatment frequency, drug formulation, delivery device). Better adherence, powered by recent technological advances in the delivery of glucagon-like peptide 1-receptor agonists, may thus lead to improved clinical outcomes in type 2 diabetes.

Effectiveness and safety of exenatide in Korean patients with type 2 diabetes inadequately controlled with oral hypoglycemic agents: an observational study in a real clinical practice

BACKGROUND

Randomized clinical trials have shown the efficacy and safety of short-acting exenatide in patients with type 2 diabetes mellitus (T2DM). The aim of this observational study was to investigate the effectiveness and safety of exenatide twice a day in Korean patients with T2DM who are suboptimally controlled with oral hypoglycemic agents.

METHODS

This study was a post hoc analysis of multi-center (71 centers), prospective, observational, single-arm, post-marketing study of short-acting exenatide 5 to 10 μg twice a day from March 2008 to March 2014 and analyzed those who finished the follow-up over 20 weeks of medication. Changes of hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), and body weight values before and after exenatide treatment were analyzed. Adverse events and adverse drug reactions were estimated in patients who were treated with exenatide at least once and for whom follow-up for safety has been completed.

RESULTS

After 20 weeks treatment with exenatide, mean HbA1c and body weight were significantly reduced from 8.4% to 7.7% and from 83.4 kg to 80.2 kg, respectively (both p < 0.001). Subjects with higher baseline glucose and HbA1c levels showed an independent association with a greater reduction in glucose level. In addition, short duration of diabetes less than 5 years was an independent predictor for the improvement in glucose level. The majority of study subjects showed a reduction in both body weight and glucose level (63.3%) after exenatide treatment. In terms of safety profile, exenatide treatment was generally well-tolerated and the incidence of severe adverse event was rare (0.8%). The gastrointestinal side effects were most common and hypoglycemia was reported in 1.7% of subjects.

CONCLUSION

In real clinical practice, 20 weeks treatment with short-acting exenatide was well tolerated and showed a significant body weight and glucose reduction in Korean patients with T2D who are suboptimally controlled with oral hypoglycemic agents.

TRIAL REGISTRATION

ClinicalTirals.gov , number NCT02090673 , registered 14 February 2008.

Current and future pharmacologic treatment of nonalcoholic steatohepatitis

PURPOSE OF REVIEW

Nonalcoholic steatohepatitis (NASH), the aggressive form of nonalcoholic fatty liver disease (NAFLD), can progress to cirrhosis and hepatocellular cancer in 5-15% of patients and is rapidly becoming the leading cause for end-stage liver disease. Dietary caloric restriction and exercise, currently the cornerstone of therapy for NAFLD, can be difficult to achieve and maintain, underscoring the dire need for pharmacotherapy. This review presents the agents currently used in managing NAFLD and their pharmacologic targets. It also provides an overview of NAFLD agents currently under development.

RECENT FINDINGS

Therapies for NASH can be broadly classified into agents that target the metabolic perturbations driving disease pathogenesis (such as insulin resistance and de novo lipogenesis) and agents that target downstream processes including cell stress, apoptosis, inflammation, and fibrosis. Modulation of peroxisome proliferator-activator receptors, farnesoid-X-receptors, and the glucagon-like peptide 1 pathway have been shown to improve liver histology. The intestinal microbiome and metabolic endotoxemia are novel targets that are currently under review. Antioxidants such as vitamin E, and more recently anti-inflammatory agents such as apoptosis signal-regulating kinase 1 inhibitors show promise as therapy for NASH. Several antifibrotic agents including cysteine-cysteine motif chemokine receptor type 2 and type 5 antagonists have been shown to inhibit the progression of fibrosis toward cirrhosis.

SUMMARY

There are currently several agents in the drug pipeline for NASH. Within the next few years, the availability of therapeutic options for NAFLD will hopefully curb the rising trend of NAFLD-related end stage liver disease.

Allostery and Biased Agonism at Class B G Protein-Coupled Receptors

Class B G protein-coupled receptors (GPCRs) respond to paracrine or endocrine peptide hormones involved in control of bone homeostasis, glucose regulation, satiety, and gastro-intestinal function, as well as pain transmission. These receptors are targets for existing drugs that treat osteoporosis, hypercalcaemia, Paget's disease, type II diabetes, and obesity and are being actively pursued as targets for numerous other diseases. Exploitation of class B receptors has been limited by difficulties with small molecule drug discovery and development and an under appreciation of factors governing optimal therapeutic efficacy. Recently, there has been increasing awareness of novel attributes of GPCR function that offer new opportunity for drug development. These include the presence of allosteric binding sites on the receptor that can be exploited as drug binding pockets and the ability of individual drugs to enrich subpopulations of receptor conformations to selectively control signaling, a phenomenon termed biased agonism. In this review, current knowledge of biased signaling and small molecule allostery within class B GPCRs is discussed, highlighting areas that have progressed significantly over the past decade, in addition to those that remain largely unexplored with respect to these phenomena.