Review of head-to-head comparisons of glucagon-like peptide-1 receptor agonists

GLP-1 RA Treatment and Dosing Patterns Among Type 2 Diabetes Patients in Six Countries: A Retrospective Analysis of Pharmacy Claims Data

INTRODUCTION

The glucagon-like peptide-1 receptor agonist (GLP-1 RA) class is evolving and expanding. This retrospective database study evaluated recent real-world treatment and dosing patterns of patients with type 2 diabetes (T2D) initiating GLP-1 RAs in Belgium (BE), France (FR), Germany (DE), Italy (IT), the Netherlands (NL), and Canada (CA).

METHODS

Adult T2D patients initiating GLP-1 RA therapy (dulaglutide [DULA], exenatide twice daily [exBID], exenatide once weekly [exQW], liraglutide [LIRA], or lixisenatide [LIXI]) from 2015 to 2016 were identified using the IQVIA (IQVIA, Durham, NC, and Danbury, CT, USA) Real-World Data Adjudicated Pharmacy Claims. The therapy initiation date was termed the 'index date.' Eligible patients had ≥ 180 days pre-index and ≥ 360 days post-index. Persistence (until discontinuation or switch) was evaluated over the variable follow-up using Kaplan-Meier (KM) survival analysis. Average daily dose (ADD) was calculated until discontinuation or switch.

RESULTS

A total of 34,649 DULA, 3616 exBID, 11,138 exQW, 48,317 LIRA, and 2,204 LIXI patients were included in the analysis (34.9-63.2% female; median age range 53-62 years; median follow-up 16-30 months). Proportion persistent at 1-year post-index was 36.8-67.2% for DULA, 5.9-44.4% for exBID, 24.7-44.2% for exQW, 22.2-57.5% for LIRA, and 15.5-40.0% for LIXI. Median time persistent (days) was 245-381 for DULA, 62-243 for exBID, 121-319 for exQW, 103-507 for LIRA, and 99-203 for LIXI. Mean ADD was 13.21-20.43 µg for exBID, 1.44-1.68 mg for LIRA, and 19.88-20.54 µg for LIXI. Mean average weekly dose (AWD) ranged from 2.03 to 2.14 mg for exQW. Mean AWD for DULA was 1.25 mg in Canada and ranged from 1.43 to 1.53 mg in the other countries.

CONCLUSION

Across six countries, persistence was highest among DULA patients and generally lowest among exBID patients. ADD/AWD for all GLP-1 RAs was in line with the recommended label. Longer-term data would be useful to obtain a better understanding of GLP-1 RA treatment patterns over time.

FUNDING

Eli Lilly and Company, Indianapolis, IN, USA.

Nonglycemic Effects of GLP-1 Agonists: From a Starling to Lizards to People

With the approval of exenatide in 2005, physicians had a new class of hypoglycemic agents available for the treatment of type 2 diabetes-the glucagon-like peptide-1 receptor agonists (or GLP-1 receptor agonists). As of this writing, there are seven drugs in this class available in the United States. In addition to demonstrating either cardiovascular risk neutrality or overt benefit, as now mandated by the United States Food and Drug Administration (FDA), many of these drugs have other, unexpected actions. It is our goal to outline these actions, some beneficial, some not. We have reviewed English-language articles in this area, not for an exhaustive study, but rather a broad search to define current understanding and perhaps generate further investigation.

Engineering NaV1.7 Inhibitory JzTx-V Peptides with a Potency and Basicity Profile Suitable for Antibody Conjugation To Enhance Pharmacokinetics

Drug discovery research on new pain targets with human genetic validation, including the voltage-gated sodium channel Na_V1.7, is being pursued to address the unmet medical need with respect to chronic pain and the rising opioid epidemic. As part of early research efforts on this front, we have previously developed Na_V1.7 inhibitory peptide-antibody conjugates with tarantula venom-derived GpTx-1 toxin peptides with an extended half-life (80 h) in rodents but only moderate in vitro activity (hNa_V1.7 IC₅₀ = 250 nM) and without in vivo activity. We identified the more potent peptide JzTx-V from our natural peptide collection and improved its selectivity against other sodium channel isoforms through positional analogueing. Here we report utilization of the JzTx-V scaffold in a peptide-antibody conjugate and architectural variations in the linker, peptide loading, and antibody attachment site. We found conjugates with 100-fold improved in vitro potency relative to those of complementary GpTx-1 analogues, but pharmacokinetic and bioimaging analyses of these JzTx-V conjugates revealed a shorter than expected plasma half-life in vivo with accumulation in the liver. In an attempt to increase circulatory serum levels, we sought the reduction of the net +6 charge of the JzTx-V scaffold while retaining a desirable Na_V in vitro activity profile. The conjugate of a JzTx-V peptide analogue with a +2 formal charge maintained Na_V1.7 potency with 18-fold improved plasma exposure in rodents. Balancing the loss of peptide and conjugate potency associated with the reduction of net charge necessary for improved target exposure resulted in a compound with moderate activity in a Na_V1.7-dependent pharmacodynamic model but requires further optimization to identify a conjugate that can fully engage Na_V1.7 in vivo.

Exciting advances in GPCR-based drugs discovery for treating metabolic disease and future perspectives

INTRODUCTION

Current pharmacological therapies that target single receptors have limited efficacy for the treatment of diabetes and obesity. Novel approaches with hybrid peptides that activate more than one receptor at once to generate beneficial effects through synergistic effects have shown promising results. Several unimolecular dual and tri-agonists, mainly associated with GPCR like GLP-1/GCG/GIP receptors, have shown exceptional efficacy in preclinical models, and are currently being evaluated in clinical trials to investigate their safety and beneficial effects in humans. Areas covered: Herein, the authors review the development of drugs used in the treatment of metabolic disease, from single agonists to the new generation of tri-agonist peptides and compile the latest knowledge available on GPCR-based drug discovery. The authors also provide the reader with their expert perspectives on this exciting area of drug development. Expert opinion: The co-agonists that have been clinically tested so far have been well tolerated and reduce body weight as well as fasting glucose levels in patients with Type 2 Diabetes Mellitus to a higher degree than single agonists alone. The promising data collected so far now warrant large scale randomized clinical trials to assess whether a unimolecular polypharmacy-based approach could translate into safe and efficacious treatments for obesity and its comorbidities.

Peptide-oligourea hybrids analogue of GLP-1 with improved action in vivo

Peptides have gained so much attention in the last decade that they are now part of the main strategies, with small molecules and biologics, for developing new medicines. Despite substantial progress, the successful development of peptides as drugs still requires a number of limitations to be addressed, including short in vivo half-lives and poor membrane permeability. Here, we describe the use of oligourea foldamers as tool to improve the pharmaceutical properties of GLP-1, a 31 amino acid peptide hormone involved in metabolism and glycemic control. Our strategy consists in replacing four consecutive amino acids of GLP-1 by three consecutive ureido residues by capitalizing on the structural resemblance of oligourea and α-peptide helices. The efficacy of the approach is demonstrated with three GLP-1-oligourea hybrids showing prolonged activity in vivo. Our findings should enable the use of oligoureas in other peptides to improve their pharmaceutical properties and may provide new therapeutic applications.

The Role of Glucagon-Like Peptide-1 in Energy Homeostasis

Energy homeostasis is coordinated by bidirectional communication pathways between the brain and peripheral organs, including adipose tissue, muscle, the pancreas, liver, and gut. Disruption of the integrated chemical, hormonal, and neuronal signals that constitute the gut-brain axis significantly contributes to disorders of metabolism and body weight. Initial studies of glucagon-like peptide-1 (GLP-1), a gut hormone released in response to the ingestion of nutrients, focused on its incretin actions to improve postprandial glucose homeostasis by enhancing meal-induced insulin secretion. However, GLP-1 is also a key player in the gut-brain regulatory axis with multiple effects on appetite and energy metabolism outside of its peripheral glucoregulatory actions. In this review, we explore the function of GLP-1 as a component of the gut-brain axis in the regulation of energy homeostasis, and consider the implications of this role for the development of therapeutic treatment options for obesity.

A Review of Practical Issues on the Use of Glucagon-Like Peptide-1 Receptor Agonists for the Management of Type 2 Diabetes

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are well established as effective treatments for patients with type 2 diabetes. GLP-1 RAs augment insulin secretion and suppress glucagon release via the stimulation of GLP-1 receptors. Although all GLP-1 RAs share the same underlying mechanism of action, they differ in terms of formulations, administration, injection devices and dosages. With six GLP-1 RAs currently available in Europe (namely, immediate-release exenatide, lixisenatide, liraglutide; prolonged-release exenatide, dulaglutide and semaglutide), each with its own characteristics and administration requirements, physicians caring for patients in their routine practice face the challenge of being cognizant of all this information so they are able to select the agent that is most suitable for their patient and use it in an efficient and optimal way. The objective of this review is to bring together practical information on the use of these GLP-1 RAs that reflects their approved use.Funding: Eli Lilly and Company.Plain Language Summary: Plain language summary available for this article.

Therapeutic medications against diabetes: What we have and what we expect

Diabetes has become one of the largest global health and economic burdens, with its increased prevalence and high complication ratio. Stable and satisfactory blood glucose control are vital to reduce diabetes-related complications. Therefore, continuous attempts have been made in antidiabetic drugs, treatment routes, and traditional Chinese medicine to achieve better disease control. New antidiabetic drugs and appropriate combinations of these drugs have increased diabetes control significantly. Besides, novel treatment routes including oral antidiabetic peptide delivery, nanocarrier delivery system, implantable drug delivery system are also pivotal for diabetes control, with its greater efficiency, increased bioavailability, decreased toxicity and reduced dosing frequency. Among these new routes, nanotechnology, artificial pancreas and islet cell implantation have shown great potential in diabetes therapy. Traditional Chinese medicine also offer new options for diabetes treatment. Our paper aim to overview these therapeutic methods for diabetes therapy. Proper combinations of these existing anti-diabetic medications and searching for novel routes are both necessary for better diabetes control.

Impact on HbA1c and body weight of switching from other GLP-1 receptor agonists to semaglutide: A model-based approach

AIMS

Semaglutide is a glucagon-like peptide-1 (GLP-1) analogue approved for the treatment of type 2 diabetes. The impact of switching treatment from another GLP-1 receptor agonist (GLP-1RA) to semaglutide was investigated by analyses of exposure-response models.

METHODS

HbA1c and body weight time-course models were developed, using up to 30 weeks of observations from four trials in the semaglutide phase 3 programme. Given the recommended dosing for each GLP-1RA, pharmacokinetic profiles were simulated based on published population pharmacokinetic models and exposure was adjusted by the relative potencies to ensure that model predictions matched the effects observed in clinical trials. After 26 weeks of simulated treatment with liraglutide, dulaglutide or exenatide extended-release, simulated semaglutide treatment was initiated 1 day after the last once-daily dose of liraglutide and 1 week after the last once-weekly doses of dulaglutide or exenatide extended-release.

RESULTS

The potency-adjusted total effective GLP-1RA concentration increased after switching from another GLP-1RA to semaglutide and was associated with reductions ranging from ~0.3% to ~0.8%-points for HbA1c and from ~2% to ~4% for body weight with semaglutide 1.0 mg. Temporary slight deteriorations in HbA1c were observed after switching to semaglutide 0.25 mg from liraglutide 1.2/1.8 mg or dulaglutide 1.5 mg.

CONCLUSIONS

Exposure-response modelling suggests that switching to semaglutide from liraglutide, dulaglutide or exenatide extended-release results in further reductions in HbA1c and body weight. Initial slight deterioration in outcome values when switching to semaglutide 0.25 mg could be avoided by initiating semaglutide treatment at a higher dose.

Long-term effects of GLP-1 receptor agonists in type 2 diabetic patients: A retrospective real-life study in 131 patients

AIM

We evaluate retrospectively long-term effects of GLP-1 receptor agonists in type 2 diabetic patients treated between 2008 and 2016.

METHODS

131 patients treated by GLP-1 receptor agonists (GLP-1RAs) were included. The objective was to evaluate the evolution of glycated hemoglobin (HbA_1c) during a period up to 4 years. The secondary objectives consisted of analysing the long-term effects of treatment on body mass index (BMI), blood pressure and lipids; reporting the proportion of patients who reached HbA_1c objectives; estimating the time before treatment failure and determining predictive factors of failure. We also compared twice-daily exenatide to once-daily liraglutide on the major parameters.

RESULTS

HbA_1c improved significantly, mostly during the first year of treatment (-1.2%), and this effect was maintained after 4 years (-1.4% vs. baseline). At 1 year, 26% and 47% of subjects achieved HbA_1c levels <7.0% and 7.5%, respectively. Treatment failure was observed in 51% of patients after a mean duration of GLP-1RA treatment of 50 months. Half of patients had failed after 42 months. Baseline HbA_1c greater than 9.0% and male gender were predictive factors of treatment failure. BMI also decreased: -0.9 kg/m² the first year, -1.9 kg/m² after 4 years. No significant difference was found between patients treated with exenatide and liragutide over time.

CONCLUSIONS

The beneficial effects of GLP-1RAs on HbA_1c reached a plateau after the first year of treatment and are maintained at 4 years only in one third of patients. Failure occurred predominantly in men with a baseline HbA_1c greater than 9%.

GLP-1RAs in type 2 diabetes: mechanisms that underlie cardiovascular effects and overview of cardiovascular outcome data

Patients with type 2 diabetes (T2DM) have a substantial risk of developing cardiovascular disease. The strong connection between the severity of hyperglycaemia, metabolic changes secondary to T2DM and vascular damage increases the risk of macrovascular complications. There is a challenging demand for the development of drugs that control hyperglycaemia and influence other metabolic risk factors to improve cardiovascular outcomes such as cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, hospitalization for unstable angina and heart failure (major adverse cardiovascular events). In recent years, introduction of the new drug class of glucagon-like peptide-1 receptor agonists (GLP-1RAs) has changed the treatment landscape as GLP-1RAs have become well-established therapies in T2DM. The benefits of GLP-1RAs are derived from their pleiotropic effects, which include appetite control, glucose-dependent secretion of insulin and inhibition of glucagon secretion. Importantly, their beneficial effects extend to the cardiovascular system. Large clinical trials have evaluated the cardiovascular effects of GLP-1RAs in patients with T2DM and elevated risk of cardiovascular disease and the results are very promising. However, important aspects still require elucidation, such as the specific mechanisms involved in the cardioprotective effects of these drugs. Careful interpretation is necessary because of the heterogeneity across the trials concerning the definition of cardiovascular risk or cardiovascular disease, baseline characteristics, routine care and event rates. The aim of this review is to describe the main clinical aspects of the GLP-1RAs, compare them using data from both the mechanistic and randomized controlled trials and discuss potential reasons for improved cardiovascular outcomes observed in these trials. This review may help clinicians to decide which treatment is most appropriate in reducing cardiovascular risk in patients with T2DM.

GLP-1 receptor agonists in diabetic kidney disease: from the patient-side to the bench-side

Diabetic kidney disease (DKD), one of the most common and severe microvascular complications of diabetes, is the leading cause of chronic kidney disease and end-stage kidney disease worldwide. Since the development of renin-angiotensin system inhibition nearly three decades ago, no new therapeutic agents have received regulatory approval for treatment of DKD. Glucagon-like peptide-1 (GLP-1) receptor agonists, a class of newer antihyperglycemic agents, have shown promise for prevention of DKD onset and progression. This perspective summarizes clinical and experimental observations to give insight into biological mechanisms beyond glycemic control, such as natriuresis and anti-inflammatory actions, for preservation of kidney function in patients with diabetes.

Glycemic Variability: How to Measure and Its Clinical Implication for Type 2 Diabetes

Glycated hemoglobin A1c (A1C) levels have traditionally been the gold standard for assessing glycemic control and treatment efficacy in patients with type 2 diabetes. However, A1C does not take into account fluctuations in blood glucose levels known as glycemic variability (GV). In recent years, GV has become increasingly clinically relevant, because of a better understanding of the need to reach target A1C while avoiding hypoglycemia. GV relates to both hyperglycemia and hypoglycemia, and has been associated with poorer quality of life. Diabetes treatments targeting multiple pathophysiological mechanisms are most beneficial in controlling A1C and reducing GV. In clinical trials, a number of metrics are used to measure GV, many of which are not well understood in the clinical practice. Until a gold standard metric for GV is established, the variety of measurements available may confound the choice of an optimal treatment for an individual patient.

The safety and efficacy of once-weekly glucagon-like peptide-1 receptor agonist semaglutide in patients with type 2 diabetes mellitus: a systemic review and meta-analysis

OBJECTIVES

To investigate the safety and efficacy of once-weekly glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide as monotherapy or add-on to other antihyperglycaemic agents (AHAs) in patients with type 2 diabetes mellitus (T2DM).

METHODS

PubMed, Embase, Cochrane library and ClinicalTrials.gov were searched from the inception to January 18, 2018. Randomised controlled trials (RCTs) comparing semaglutide with placebo or other AHAs in T2DM patients were included in our meta-analysis. Risk ratio (RR) and mean difference (MD) with 95% confidence intervals (CI) were used to evaluate the outcomes.

RESULTS

A total of 11 studies with 9519 patients were included in our meta-analysis. The results revealed that compared with placebo or other AHAs, semaglutide had further reduced the level of haemoglobin A1c (HbA1c) [MD 1.03%, 95% CI (0.85%, 1.22%), p < 0.00001], self-measured plasma glucose (SMPG) [MD 1.19 mmol/L, 95% CI (0.84 mmol/L, 1.53 mmol/L), p < 0.00001], fasting plasma glucose (FPG) [MD 1.33 mmol/L, 95% CI (0.97 mmol/L, 1.69 mmol/L), p < 0.00001] and weight [MD 3.61 kg, 95% CI (3.05 kg, 4.17 kg), p < 0.00001] and significantly increased participants who achieved HbA1c < 7.0% [RR 2.26, 95% CI (1.89, 2.70), p < 0.00001] in T2DM patients. Semaglutide had a significant increase in the incidence of adverse events (AEs) [RR 1.06, 95% CI (1.02, 1.11), p < 0.0001] and an analogous incidence in serious adverse events (SAEs) [RR 0.94, 95% CI (0.86, 1.02), p = 0.11] and hypoglycaemic events (severe or blood glucose (BG)-confirmed symptomatic) [RR 0.93, 95% CI (0.74, 1.16), p = 0.50] compared with the control group.

CONCLUSIONS

This article revealed that semaglutide had a favourable efficacy and safety in treating T2DM patients. It maybe a superior choice for T2DM patients who have obesity or a poor adherence to daily AHAs.

12-month effects of incretins versus SGLT2-Inhibitors on cognitive performance and metabolic profile. A randomized clinical trial in the elderly with Type-2 diabetes mellitus

AIM

The aim of the present study is to examine the effects on cognitive performance, anthropometric measures, and metabolic markers in 2 different treatments: Incretins vs sodium-glucose co-transporter-2 inhibitors (SGLT2-I).

MATERIALS AND METHODS

A randomized controlled clinical trial was carried out on 39 elderly subjects (23 men and 16 women) with type 2 diabetes mellitus, with a mean age of 77.21±8.07 years. Body mass index (BMI) of 29.92±4.31 kg/m2 and a cognitive status measured by a Mini Mental State Examination (scores >27 points). The subjects were on a 3-month treatment with a maximal dose of metformin as a stable regime, with the addition of incretins (liraglutide at doses of up to 1.8 mg/d; vildagliptin at 100 mg/d; sitagliptin 100 mg/d; and linagliptin 5 mg/d), or SGLT2-I (canagliflozin 300 mg/d; empagliflozin 25 mg/d; and dapagliflozin 10 mg/d). Glucose control was monitored by fasting glucose and glycosylated hemoglobin. Cognitive performance (by way of Verbal Fluency Test, Attentive Matrices Test, and Babcock Story Recall Test), anthropometric measures, and plasma lipids were also evaluated.

RESULTS

Cognitive status did not change significantly during the 12 months of treatment in either group: Verbal Fluency Test: (SGLT2-I: P=1.00, incretins: P=0.598); Babcock Story Recall Test (SGLT2-I: P=0.391; incretins: P=0.351); and Attentive Matrices Test (SGLT2-I: P=0.679, incretins: P=0.901). SGLT2-I also resulted in a reduction in weight (-1.95 kg; P<0.05), in BMI (-0.69 kg/m2; P<0.05) and an increase in high-density lipoprotein cholesterol (+5.73 mg/dl; P<0.01).

CONCLUSION

Preliminary data show that patients treated with incretins and SGLT2-I have not suffered a reduction in cognitive performance during the 1 year of treatment. Metabolic outcome seemed to benefit, in particular, in patients who were treated with SGLT2-I.

Harmony Outcomes: A randomized, double-blind, placebo-controlled trial of the effect of albiglutide on major cardiovascular events in patients with type 2 diabetes mellitus-Rationale, design, and baseline characteristics

BACKGROUND

Albiglutide is a long-acting glucagon-like peptide-1 receptor agonist that improves glycemic control in patients with type 2 diabetes mellitus (T2DM). Harmony Outcomes is a randomized, double-blind, placebo-controlled trial of the effect of albiglutide on major adverse cardiovascular (CV) events in patients with T2DM and established CV disease.

METHODS

The trial was designed to recruit 9,400 patients aged ≥40 years with T2DM, prior atherosclerotic CV disease, and suboptimal glycemic control. Participants were assigned in a 1:1 ratio to albiglutide 30 mg (potentially increasing to 50 mg) or matching placebo administered once weekly by subcutaneous injection. The trial will continue until ≥611 confirmed primary outcome events (CV death, myocardial infarction, or stroke) occur over a median follow-up of at least 1.5 years.

RESULTS

A total of 9,463 patients were enrolled at 611 sites in 28 countries between July 2015 and December 2016. The mean age was 64.1 years; duration of T2DM, 13.8 years; and glycated hemoglobin, 8.7%. The percentage of patients with prior coronary artery disease was 70.5%; peripheral arterial disease, 25.0%; stroke, 17.7%; heart failure, 20.2%; and chronic kidney disease, 22.6%.

CONCLUSIONS

Harmony Outcomes will assess the CV safety of albiglutide in patients with T2DM and CV disease. Trials of other agents in the glucagon-like peptide-1 receptor agonist class have shown CV benefit for only some of these medications, possibly due to differences in trial design or instead due to differences in drug structure or metabolism. Harmony Outcomes will provide information critical to our understanding of this heterogenous class of glucose-lowering agents.

Semaglutide induces weight loss in subjects with type 2 diabetes regardless of baseline BMI or gastrointestinal adverse events in the SUSTAIN 1 to 5 trials

AIMS

To assess the effect of baseline body mass index (BMI) and the occurrence of nausea and/or vomiting on weight loss induced by semalgutide, a once-weekly glucagon-like peptide 1 analogue for the treatment of type 2 diabetes. Semaglutide demonstrated superior reductions in HbA1c and superior weight loss (by 2.3-6.3 kg) versus different comparators across the SUSTAIN 1 to 5 trials; the contributing factors to weight loss are not established.

MATERIALS AND METHODS

Subjects with inadequately controlled type 2 diabetes (drug-naïve or on background treatment) were randomized to subcutaneous semaglutide 0.5 mg (excluding SUSTAIN 3), 1.0 mg (all trials), or comparator (placebo, sitagliptin, exenatide extended release or insulin glargine). Subjects were subdivided by baseline BMI and reporting (yes/no) of any nausea and/or vomiting. Change from baseline in body weight was assessed within each trial and subgroup. A mediation analysis separated weight loss into direct or indirect (mediated by nausea or vomiting) effects.

RESULTS

Clinically relevant weight-loss differences were observed across all BMI subgroups, with a trend towards higher absolute weight loss with higher baseline BMI. Overall, 15.2% to 24.0% and 21.5% to 27.2% of subjects experienced nausea or vomiting with semaglutide 0.5 and 1.0 mg, respectively, versus 6.0% to 14.1% with comparators. Only 0.07 to 0.5 kg of the treatment difference between semaglutide and comparators was mediated by nausea or vomiting (indirect effects).

CONCLUSIONS

In SUSTAIN 1 to 5, semaglutide-induced weight loss was consistently greater versus comparators, regardless of baseline BMI. The contribution of nausea or vomiting to this weight loss was minor.

Clinical pharmacology of glucagon-like peptide-1 receptor agonists

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are an important asset in the armamentarium for the treatment of type 2 diabetes mellitus (type 2 DM). Incretin failure is a critical etiopathogenetic feature of type 2 DM, which, if reversed, results in improved glycaemic control. GLP-1 RAs are injectable peptides that resemble the structure and function of endogenous incretin GLP-1, but as they are not deactivated by the dipeptidyl peptidase-4 (DPP-4), their half-life is prolonged compared with native GLP-1. Based on their ability to activate GLP-1 receptor, GLP-1 RAs are classified as short-acting (exenatide twice-daily and lixisenatide once-daily), and long-acting (liraglutide once-daily and the once-weekly formulations of exenatide extended-release, dulaglutide, and albiglutide). Semaglutide, another long-acting, once-weekly GLP-1 RA, was recently approved by the FDA and EMA. Although all of these agents potently reduce haemoglobin A1C (HbA1c), there are unique features and fundamental differences among them related to fasting and postprandial hyperglycaemia reduction, weight loss potency, cardiovascular protection efficacy, and adverse events profile. It is imperative that current evidence be integrated and applied in the context of an individualised patient-centred approach. This should include not only glucose management but also targeting as many as possible of the pathophysiologic mechanisms responsible for type 2 DM development and progression.

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.

Glucagon-like peptide-1 (GLP-1) action in the mouse area postrema neurons

Glucagon-like peptide-1 (GLP-1) is a peptide hormone and member of the incretin family. GLP-1 related drugs, such as liraglutide, are widely used to treat diabetic patients and work by stimulating pancreatic β cells to increase glucose-dependent insulin secretion. However, extrapancreatic effects, such as appetite suppression or emesis, are observed in response to GLP-1 receptor agonists. In this study we used the in vitro patch-clamp method in acute brainstem preparations of mice and demonstrated that GLP-1 acts directly on area postrema neurons. It is known that activation of the area postrema is related to the induction of homeostatic autonomic nervous systems, including nausea. Approximately,half of the neurons tested in the area postrema were excited by GLP-1 in the presence of tetrodotoxin, and is thought to be through adenylate cyclase-cAMP pathways. Excitation was not frequently observed in nucleus tractus solitaries neurons or in area postrema neurons from GLP-1 receptor knock-out mice. These results indicate that GLP-1 receptor agonists excite area postrema neurons and potentially leading to the expression of extra-pancreatic effects. This is the first study to show that GLP-1 directly activates area postrema neurons.

Cardiovascular Effects of Different GLP-1 Receptor Agonists in Patients with Type 2 Diabetes

PURPOSE OF REVIEW

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have positive effects on weight loss, blood pressure, hyperlipidemia, and glycemic control. They exhibit a broad range of effects on the cardiovascular system that are independent of changes in blood glucose. Cardiovascular outcome trials have demonstrated safety of GLP-1 RAs but results for cardiovascular efficacy were varied. The aim of the present review is the assessment of the effects of GLP-1 RAs on cardiovascular risk factors, and major cardiovascular events.

RECENT FINDINGS

Use of GLP-1 RAs was associated with relative risk reduction in cardiovascular mortality and all-cause mortality with no significant differences for the incidence of severe hypoglycemia, pancreatitis, pancreatic cancer, or medullary thyroid cancer when compared to placebo. Although there are differences between individual medications with respect to their effects on cardiovascular events, GLP-1 RAs offer a favorable risk-benefit profile. The present review confirms the cardiovascular safety and efficacy vs placebo of GLP-1 RAs in patients with type 2 diabetes at moderate-to-high atherosclerotic cardiovascular risk without significant side effects. Although professional guidelines recommend metformin as the sole first-line agent, GLP-1 RAs can be used as first-line therapy in individuals with type 2 diabetes who either are intolerant to metformin or have high cardiovascular risk factors.

Cardiovascular benefits of GLP-1 agonists in type 2 diabetes: a comparative review

Type 2 diabetes (T2D) carries risks of both cardiovascular (CV) (myocardial infarction, stroke, and peripheral vascular disease) and microvascular (retinopathy/nephropathy/neuropathy) complications. Glucose-lowering is an effective strategy for preventing microvascular complications, but the extent to which it can reduce CV complications is less certain. Glucagon-like peptide-1 (GLP-1) agonists are potent glucose-lowering agents but also have potentially beneficial effects on other traditional (body weight, blood pressure (BP), and LDL cholesterol) and non-traditional risk factors (low grade inflammation and endothelial dysfunction). The results of four large CV outcome trials with GLP-1 agonists are now available. These have compared lixisenatide (ELIXA), liraglutide (LEADER), semaglutide (SUSTAIN-6), and long-acting exenatide (EXSCEL) with placebo and standard of care over 2–4 years; four others (including with dulaglutide and albiglutide) are ongoing. LEADER and SUSTAIN-6 have demonstrated reductions in rates of major adverse CV events with active GLP-1 treatment but ELIXA and EXSCEL have not. In this review, we discuss the mechanisms by which GLP-1 receptor agonists act on the CV system and the design and conduct of these trials. Contrary to the assertions that (a) all GLP-1 agonists reduce CV disease in T2D but to different extents or (b) the magnitude of CV protection is predominantly related to glucose-lowering, we argue that CV benefit is specific to agents that provide longer acting agonism at the GLP-1 receptor. The mechanisms involve reduction in body weight and BP, and lowering of LDL-cholesterol and glucose, but pleiotropic effects—including suppression of low grade inflammation, vasodilation, and natriuresis—are also likely relevant.

Effect of once weekly dulaglutide by baseline beta-cell function in people with type 2 diabetes in the AWARD programme

Glucagon-like peptide-1 receptor agonists lower blood glucose in type 2 diabetes (T2D) partially through glucose-dependent stimulation of insulin secretion. The aim of this study was to investigate whether beta-cell function (as measured by HOMA2-%B) at baseline affects the glycaemic response to dulaglutide. Dulaglutide-treated patients from AWARD-1, AWARD-3 and AWARD-6 clinical studies were categorised based on their homeostatic model assessment of beta-cell function (HOMA2-%B) tertiles. Changes in glycaemic measures in response to treatment with once-weekly dulaglutide were evaluated in each HOMA2-%B tertile. Patients with low HOMA2-%B had higher baseline glycated haemoglobin (HbA1c), fasting and postprandial blood glucose, and longer duration of diabetes (P < .001, all) (mean low, middle and high tertiles with dulaglutide 1.5 mg: HOMAB-2%B, 31%, 58%, 109%; HbA1c, 8.7%, 7.7%, 7.3%, respectively). At 26 weeks, the low tertile experienced larger reductions in HbA1c compared to the high tertile with dulaglutide 1.5 mg (mean; -1.55% vs. -0.98% [-16.94 vs. -10.71 mmol/mol]). Differences between low and high tertiles disappeared when adjusted for baseline HbA1c (LSM; -1.00 vs. -1.18% [-10.93 vs. -12.90 mmol/mol]). Greater decreases in fasting blood glucose and greater increases in fasting C-peptide were observed in the low tertile. Similar increases in HOMA2-%B were observed in all tertiles. Dulaglutide demonstrated clinically relevant HbA1c reduction irrespective of estimated baseline beta-cell function.

Exenatide has a pronounced effect on energy intake but not energy expenditure in non-diabetic subjects with obesity: A randomized, double-blind, placebo-controlled trial

AIMS

Exenatide is a glucagon-like peptide 1 (GLP-1) mimetic which induces weight loss predominantly, it is presumed, via decreased food intake. However, circulating GLP-1 is also a determinant of energy expenditure. We sought to quantify the effect of exenatide on energy expenditure (EE) and energy intake.

MATERIALS AND METHODS

In this single-center, randomized double-blind placebo controlled trial, we randomized 80 healthy, non-diabetic volunteers with obesity (46 women, age: 34.4 ± 8.7 y, body fat by DXA: 44.2 ± 7.8%) to subcutaneous exenatide 10 μg twice daily or placebo. Subjects were admitted to our clinical research unit for measurement of 24 h-EE in a whole-room indirect calorimeter and ad libitum food intake using an automated vending machine paradigm before and after randomization. Furthermore, energy expenditure and ad libitum food intake measures were repeated at 24-week after readmission for 7-day inpatient stay. Body weight was obtained weekly for up to 5 weeks and was recorded at each monthly follow up visit up to 24 weeks.

RESULTS

Prior to randomization, participants over ate during the 3-day vending machine period in the whole study group (114.6 ± 35.2%), expressed as percentage of weight maintaining energy needs (WMEN) with those who were eventually randomized to exenatide overeating more (121.6 ± 37.7%) compared to placebo group (107.6 ± 31.5%). In the exenatide group, ad libitum absolute energy intake decreased by 1016.1 ± 724.5 kcal/day (95% CI: -1250.9 to -781.2) versus a 245.1 ± 710.5 kcal/day (95% CI: -475.4 to -14.7) decrease in placebo (Δ = -624.8 Kcal/day, p < 0.0001) whereas the reduction in ad libitum caloric intake relative to WMEN was a more modest 366.8 ± 752.1 kcal/day (95% CI: -614.0 to -119.6) decrease compared to 8.0 ± 860.1 kcal/day (95% CI: -286.8 to 270.8) reduction in placebo (Δ = -382.3 Kcal/day, p = 0.03). The decrease was uniform across all macronutrients groups. No differences in 24hEE or substrate oxidation rates were found. In the exenatide group, body weight decreased more over the 5 weeks (β = -0.039 kg/week, p = 0.02) and was lower compared to placebo at the end of fifth week (-1.48 ± 0.77 kg; 95% CI: -3.02 to 0.05, p = 0.06). At the 24-week follow up, there was no difference in energy intake between exenatide group and placebo group and the treatment group decreased 24-h EE more compared to placebo (β = -160.6 Kcal/day, 95% CI: -307.6 to 13.6, p = 0.03) compared to their pre-randomization measurement. However, this reduction was not present after adjustment for changes in FM and FFM (β = -87 kcal/day, p = 0.14). No difference was observed in body weight (Δ = -1.72 kg, 95% CI: -5.77 to 2.30, p = 0.39) in exenatide versus placebo over 24 weeks.

CONCLUSION

Compared with placebo, exenatide decreased early ad libitum energy intake but did not change 24 h-EE. However, the reduction was more modest in relative versus absolute terms (i.e. below that needed for WMEN). Thus, although rate of weight change was greater in the exenatide treated subjects at 5 weeks, the absolute difference in weight was not significant. These findings indicate that although exenatide reduces food intake, it may be more beneficial in blunting overeating and thus may serve to more prevent weight regain following initial weight loss.

Plausibility criteria for putative pathophysiological mechanisms in functional gastrointestinal disorders: a consensus of experts

BACKGROUND AND AIMS

The functional gastrointestinal disorders (FGIDs) are extremely common conditions associated with a considerable personal, social and health economic burden. Managing FGIDs in clinical practice is challenging because of the uncertainty of symptom-based diagnosis, the high frequency of overlap between these conditions and the limited efficacy of available therapies. It has often been argued that successful drug development and management of FGIDs requires knowledge of the underlying pathophysiology. Numerous and highly variable candidate pathophysiological mechanisms have been implicated in the generation of FGID symptoms, but there is no current consensus on how to best define the relevance of these disturbances.

METHODS

A group of international experts on FGIDs developed plausibility criteria that should be fulfilled by relevant pathophysiological mechanisms in FGIDs.

RESULTS

Five criteria are proposed: (1) the presence of the abnormality in a subset of patients, (2) temporal association between proposed mechanism and symptom(s), (3) correlation between the level of impairment of the mechanism and symptom(s), (4) induction of the symptom(s) by provoking the pathophysiological abnormality in healthy subjects and (5) treatment response by a therapy specifically correcting the underlying disorder or congruent natural history of symptoms and dysfunction in the absence of specific therapy. Based on strength of evidence for these five criteria according to the Grading of Recommendations Assessment, Development and Evaluation system, a plausibility score can be calculated for each mechanism.

CONCLUSION

Evaluation of the strength of evidence for candidate pathophysiological abnormalities fulfilling these five plausibility criteria will help to identify the most relevant mechanisms to target for novel diagnostic approaches and for the development of new therapies.

Chemical Strategies for Half-Life Extension of Biopharmaceuticals: Lipidation and Its Alternatives

Strategies for half-life extension are often required in the design of new biopharmaceuticals. This Viewpoint focuses on chemical moieties that convey protraction by albumin binding or by self-assembly to form larger structures, with GLP-1 and insulin as examples.

Patients with Obesity Caused by Melanocortin-4 Receptor Mutations Can Be Treated with a Glucagon-like Peptide-1 Receptor Agonist

Pathogenic mutations in the appetite-regulating melanocortin-4 receptor (MC4R) represent the most common cause of monogenic obesity with limited treatment options. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) cause weight loss by reducing appetite. We assessed the effect of the GLP-1 RA liraglutide 3.0 mg for 16 weeks in 14 obese individuals with pathogenic MC4R mutations (BMI 37.5 ± 6.8) and 28 matched control participants without MC4R mutation (BMI 36.8 ± 4.8). Liraglutide decreased body weight by 6.8 kg ± 1.8 kg in individuals with pathogenic MC4R mutations and by 6.1 kg ± 1.2 kg in control participants. Total body fat, waist circumference, and fasting and postprandial glucose concentrations similarly decreased in both groups. Thus, liraglutide induced an equal, clinically significant weight loss of 6% in both groups, indicating that the appetite-reducing effect of liraglutide is preserved in MC4R causal obesity and that liraglutide acts independently of the MC4R pathway. Thus, liraglutide could be an effective treatment of the most common form of monogenic obesity.

Glucagon-like peptide 1 in health and disease

In healthy individuals, the incretin hormone glucagon-like peptide 1 (GLP1) potentiates insulin release and suppresses glucagon secretion in response to the ingestion of nutrients. GLP1 also delays gastric emptying and increases satiety. In patients with type 2 diabetes mellitus (T2DM), supraphysiological doses of GLP1 normalize the endogenous insulin response during a hyperglycaemic clamp. Owing to the short plasma half-life of native GLP1, several GLP1 receptor agonists (GLP1RAs) with longer half-lives have been developed for the treatment of T2DM. These compounds vary in chemical structure, pharmacokinetics and size, which results in different clinical effects on hyperglycaemia and body weight loss; these variations might also explain the difference in cardiovascular effect observed in large-scale cardiovascular outcome trials, in which certain GLP1RAs were shown to have a positive effect on cardiovascular outcomes. Owing to their metabolic effects, GLP1RAs are also considered for the treatment of several other lifestyle-induced conditions, such as obesity, prediabetes and liver disease. This Review provides insights into the physiology of GLP1 and its involvement in the pathophysiology of T2DM and an overview of the currently available and emerging GLP1RAs. Furthermore, we review the results from the currently available large-scale cardiovascular outcome trials and the use of GLP1RAs for other indications.

Semaglutide: The Newest Once-Weekly GLP-1 RA for Type 2 Diabetes

OBJECTIVE

To review efficacy and safety of the glucagon-like peptide-1 receptor agonist (GLP-1 RA) semaglutide for type 2 diabetes (T2D).

DATA SOURCES

A literature search of PubMed/MEDLINE and EMBASE using the term semaglutide was completed through April 2018. A search of clinicaltrials.gov was also conducted.

STUDY SELECTION AND DATA EXTRACTION

English-language studies assessing the efficacy and/or safety of semaglutide were evaluated.

DATA SYNTHESIS

Semaglutide is a newly approved GLP-1 RA for the treatment of T2D. Administered once weekly at a dose of 0.5 or 1 mg, it has been compared with placebo, sitagliptin, insulin glargine, a combination of oral antidiabetic therapies, and 2 GLP-1 RAs, exenatide ER and dulaglutide, and demonstrated greater efficacy compared with these therapies. Published data from studies ranging from 30 to 104 weeks duration demonstrate efficacy with decreases in hemoglobin A1C (A1C) ranging from 1.1% to 2.2%. Studies show reductions in weight from 1.4 to 6.5 kg. Semaglutide demonstrated a reduction in the composite outcome of cardiovascular (CV) death, nonfatal myocardial infarction, or nonfatal stroke compared with placebo in patients at high risk of CV events (hazard ratio = 0.74; P = 0.02). Common adverse effects include nausea, vomiting, and diarrhea as seen with other GLP-1 RAs. Relevance to Patient Care and Clinical Practice: Semaglutide represents an attractive GLP-1 RA considering its A1C and weight reduction. It provides patient convenience and high patient satisfaction.

CONCLUSIONS

Semaglutide is an appealing option for the treatment of T2D as a once-weekly GLP-1 RA with established glycemic, CV, and weight benefits.

Molecular Mechanisms Underlying the Cardiovascular Benefits of SGLT2i and GLP-1RA

PURPOSE OF REVIEW

In addition to their effects on glycemic control, two specific classes of relatively new anti-diabetic drugs, namely the sodium glucose co-transporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) have demonstrated reduced rates of major adverse cardiovascular events (MACE) in subjects with type 2 diabetes (T2D) at high risk for cardiovascular disease (CVD). This review summarizes recent experimental results that inform putative molecular mechanisms underlying these benefits.

RECENT FINDINGS

SGLT2i and GLP-1RA exert cardiovascular effects by targeting in both common and distinctive ways (A) several mediators of macro- and microvascular pathophysiology: namely (A1) inflammation and atherogenesis, (A2) oxidative stress-induced endothelial dysfunction, (A3) vascular smooth muscle cell reactive oxygen species (ROS) production and proliferation, and (A4) thrombosis. These agents also exhibit (B) hemodynamic effects through modulation of (B1) natriuresis/diuresis and (B2) the renin-angiotensin-aldosterone system. This review highlights that while GLP-1RA exert direct effects on vascular (endothelial and smooth muscle) cells, the effects of SGLT2i appear to include the activation of signaling pathways that prevent adverse vascular remodeling. Both SGLT2i and GLP-1RA confer hemodynamic effects that counter adverse cardiac remodeling.

Semaglutide: Review and Place in Therapy for Adults With Type 2 Diabetes

Guidelines increasingly highlight the importance of multifactorial management in type 2 diabetes, in contrast to the more traditional focus on glycemic control. Semaglutide, a recently approved glucagon-like peptide-1 receptor agonist, is indicated in Canada for adults with type 2 diabetes to improve glycemic control as monotherapy with diet and exercise when metformin is inappropriate or as an add-on to either metformin alone or metformin plus a sulfonylurea or basal insulin. The Semaglutide Unabated Sustainability in Treatment of Type 2 Diabetes (SUSTAIN) clinical trial program for semaglutide comprises 6 pivotal global phase 3a trials (SUSTAIN 1 through 6) and 2 Japanese phase 3a trials. Phase 3b trials include SUSTAIN 7, and SUSTAIN 8 and 9 (both ongoing). Results from the completed trials support the superiority of semaglutide for reduction of glycated hemoglobin levels and weight loss vs. placebo as well as active comparators, including sitagliptin, exenatide extended-release, dulaglutide and insulin glargine. SUSTAIN 6 trial data confirmed cardiovascular safety and demonstrated significant reductions in major cardiovascular events with semaglutide vs. placebo, an outcome that confirmed the noninferiority of semaglutide. The robust and sustained effects of semaglutide on glycated hemoglobin levels and weight loss vs. comparators, as well as its safety and possible cardiovascular benefit, address an unmet need in the treatment of type 2 diabetes. This article overviews data from across the semaglutide clinical trial program, including efficacy and safety results and findings from post hoc analyses. The potential place of semaglutide in clinical practice is discussed.

Semaglutide Added to Basal Insulin in Type 2 Diabetes (SUSTAIN 5): A Randomized, Controlled Trial

CONTEXT

Combination therapy with insulin and glucagon-like peptide-1 receptor agonists (GLP-1RAs) is important for treating type 2 diabetes (T2D). This trial assesses the efficacy and safety of semaglutide, a GLP-1RA, as an add-on to basal insulin.

OBJECTIVE

To demonstrate the superiority of semaglutide vs placebo on glycemic control as an add-on to basal insulin in patients with T2D.

DESIGN

Phase 3a, double-blind, placebo-controlled, 30-week trial.

SETTING

This study included 90 sites in five countries.

PATIENTS

We studied 397 patients with uncontrolled T2D receiving stable therapy with basal insulin with or without metformin.

INTERVENTIONS

Subcutaneous semaglutide 0.5 or 1.0 mg once weekly or volume-matched placebo.

MAIN OUTCOME MEASURES

Primary endpoint was change in glycated Hb (HbA1c) from baseline to week 30. Confirmatory secondary endpoint was change in body weight from baseline to week 30.

RESULTS

At week 30, mean HbA1c reductions [mean baseline value, 8.4% (67.9 mmol/mol)] with semaglutide 0.5 and 1.0 mg were 1.4% (15.8 mmol/mol) and 1.8% (20.2 mmol/mol) vs 0.1% (1.0 mmol/mol) with placebo [estimated treatment difference (ETD) vs placebo, -1.35 (14.8 mmol/mol); 95% CI, -1.61 to -1.10 and ETD, -1.75% (19.2 mmol/mol); 95% CI, -2.01 to -1.50; both P < 0.0001]. Severe or blood glucose-confirmed hypoglycemic episodes were reported in 11 patients (17 events) and 14 patients (25 events) with semaglutide 0.5 and 1.0 mg, respectively, vs seven patients (13 events) with placebo (estimated rate ratio vs placebo, 2.08; 95% CI, 0.67 to 6.51 and estimated rate ratio vs placebo, 2.41; 95% CI, 0.84 to 6.96 for 0.5 and 1.0 mg; both P = nonsignificant). Mean body weight decreased with semaglutide 0.5 and 1.0 mg vs placebo from baseline to end of treatment: 3.7, 6.4, and 1.4 kg (ETD, -2.31; 95% CI, -3.33 to -1.29 and ETD, -5.06; 95% CI, -6.08 to -4.04 kg; both P < 0.0001). Premature treatment discontinuation due to adverse events was higher for semaglutide 0.5 and 1.0 mg vs placebo (4.5%, 6.1%, and 0.8%), mainly due to gastrointestinal disorders.

CONCLUSIONS

Semaglutide, added to basal insulin, significantly reduced HbA1c and body weight in patients with uncontrolled T2D vs placebo.

Pharmacokinetics and tolerability of semaglutide in people with hepatic impairment

AIMS

To investigate whether the pharmacokinetic characteristics of semaglutide were altered in people with hepatic impairment, assessed using Child-Pugh criteria, vs those with normal hepatic function.

METHODS

In this multicentre, open-label, parallel-group trial (sponsor Novo Nordisk, ClinicalTrials.gov ID NCT02210871), four groups of participants with normal hepatic function (n = 19) or mild (n = 8), moderate (n = 10) or severe (n = 7) hepatic impairment received a single, subcutaneous dose of 0.5 mg semaglutide. Semaglutide plasma concentrations were assessed frequently for 35 days after dosing. The primary endpoint was area under the semaglutide plasma concentration-time curve from time zero to infinity (AUC_0-∞ ). No effect of hepatic impairment was declared if the 90% confidence interval (CI) for the between-group ratio (hepatic impairment/normal function) was within the interval 0.70 to 1.43.

RESULTS

Semaglutide exposure was similar across all groups, with AUC_0-∞ treatment ratios for mild impairment/normal function of 0.95 (90% CI 0.77, 1.16), moderate impairment/normal function 1.02 (90% CI 0.93, 1.12), and severe impairment/normal function 0.97 (90% CI 0.84, 1.12). The maximum plasma semaglutide concentration (C_max ) did not appear to be influenced by hepatic function, with mild impairment/normal function treatment ratios of 0.99 (90% CI 0.80, 1.23), moderate impairment/normal function 1.02 (90% CI 0.88, 1.18) and severe impairment/normal function 1.15 (90% CI 0.89, 1.48; sensitivity analysis excluding one extreme semaglutide concentration: 1.05 [90% CI 0.88, 1.25]). In all, 10 participants reported 12 mild or moderate non-serious adverse events. No unexpected safety or tolerability issues were observed.

CONCLUSIONS

Semaglutide exposure did not appear to be affected by hepatic impairment, suggesting that dose adjustment may not be necessary in patients with hepatic impairment. Semaglutide was well tolerated and there were no unexpected safety issues.

Glucagon-like Peptide-1 Receptor Agonists and Cardiovascular Events: Class Effects versus Individual Patterns

Several new glucose-lowering medications have been approved, such as dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1RAs), and sodium glucose cotransporter-2 inhibitors. Among GLP-1RAs, lixisenatide, a short-acting drug, did not show cardiovascular (CV) benefits in patients with Type 2 diabetes mellitus (T2D) and acute coronary syndrome. Extended-release exenatide was also not significantly better for CV outcomes. By contrast, once daily liraglutide and once weekly semaglutide, both long-acting GLP-1RAs, decreased the incidence of major adverse CV events and mortality. This Review attempts to explain favorable CV results with some, but not all, GLP-1RAs, to aid in their differential prescription with the aim of further reducing the adverse CV burden of T2D.

Newer GLP-1 receptor agonists and obesity-diabetes

Obesity is a major risk factor for type 2 diabetes and may complicate type 1 diabetes. In parallel with the global epidemic of obesity, the incidence of type 2 diabetes is increasing exponentially. To reverse these alarming trends, weight loss becomes a major therapeutic priority in prevention and treatment of type 2 diabetes. Given that glucagon-like peptide-1 receptor agonists (GLP-1 RAs) improve glycaemic control and cause weight loss, they are receiving increasing attention for the treatment of diabetes-obesity. This review discusses current and emerging therapeutic options with GLP-1 RAs and considers the next generation of novel peptide co-agonists with the potential for improved therapeutic outcomes in obesity and type 2 diabetes.

Incretins: Beyond type 2 diabetes

While the use of incretins, including GLP-1 receptor agonists and PDD-IV inhibitors, is well established in the treatment of type 2 diabetes, many other aspects of these agents are yet to be discovered and utilized for their potential clinical benefit. These include the potential role of GLP-1 receptor agonists in the induction of weight loss, blood pressure reduction, anti-inflammatory and nephro- and cardio-protective actions. Their potential benefit in type 1 diabetes is also being investigated. This review will attempt to comprehensively describe novel discoveries in the field of incretin pathophysiology and pharmacology beyond their classical role in the treatment of type 2 diabetes.

A comparative safety review between GLP-1 receptor agonists and SGLT2 inhibitors for diabetes treatment

INTRODUCTION

Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium glucose cotransporter 2 inhibitors (SGLT2i) are of particular interest in type 2 diabetes treatment strategies, due to their efficacy in reducing HbA1c with a low risk of hypoglycaemia, to their positive effects on body weight and blood pressure and in light of their effects on cardiovascular risk and on nephroprotection emerged from the most recent cardiovascular outcome trials. Since it is therefore very likely that GLP-1RA and SGLT2i use will become more and more common, it is more and more important to gather and discuss information about their safety profile.

AREAS COVERED

Adverse events and the safety concerns most often emerged in trials with GLP-1RA namely, exenatide long acting release (LAR), dulaglutide, liraglutide, semaglutide, lixisenatide or SGLT2i, namely empagliflozin, dapagliflozin, canagliflozin and SGLT2i with an attempt at comparing the safety profiles of molecules of these two classes.

EXPERT OPINION

GLP-1RA and SGLT2i, although each associated with different specific side effects, share a 'similar' safety profile and are both drugs relatively easy to handle. The potentially complementary mechanisms of action, the cardio and nephroprotective effects demonstrated by molecules of both classes, make these drugs potentially useful even in add on to each other.