Effects of glucagon-like peptide-1 receptor agonists on weight loss: systematic review and meta-analyses of randomised controlled trials

[Incretin-based co- and tri-agonists : Innovative polypharmacology for the treatment of obesity and diabetes]

BACKGROUND

The worldwide rise in overweight and obesity is paralleled by an increasing prevalence of type-2 diabetes. Apart from bariatric surgery, treatment options to decrease body weight are often underwhelming. Innovative pharmacological options are required to cope with the global "diabesity" pandemic.

OBJECTIVES

Particular novel pharmacological approaches are discussed, with a special focus on polyagonist-based pharmacotherapies.

MATERIALS AND METHODS

Articles on co- and tri-agonists for the treatment of obesity and diabetes are presented and discussed.

RESULTS

Unimolecular peptides have been developed for the treatment of obesity and type-2 diabetes. These peptides activate the receptors of multiple hormones and bundle their positive effects in one single molecule. In preclinical studies, polyagonists targeting the receptors for glucagon-like peptide-1 (GLP-1), glucagon, or glucose-dependent insulinotropic peptide (GIP) were promising to reduce body weight and blood glucose. GLP-1-mediated delivery of the nuclear hormones estrogen or dexamethasone also yielded beneficial effects in preclinical studies of obesity.

CONCLUSIONS

Polyagonists represent an innovative strategy for the development of novel pharmacotherapies to treat obesity and diabetes.

How Satiating Are the 'Satiety' Peptides: A Problem of Pharmacology versus Physiology in the Development of Novel Foods for Regulation of Food Intake

Developing novel foods to suppress energy intake and promote negative energy balance and weight loss has been a long-term but commonly unsuccessful challenge. Targeting regulation of appetite is of interest to public health researchers and industry in the quest to develop ‘functional’ foods, but poor understanding of the underpinning mechanisms regulating food intake has hampered progress. The gastrointestinal (GI) or ‘satiety’ peptides including cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) secreted following a meal, have long been purported as predictive biomarkers of appetite response, including food intake. Whilst peptide infusion drives a clear change in hunger/fullness and eating behaviour, inducing GI-peptide secretion through diet may not, possibly due to modest effects of single meals on peptide levels. We conducted a review of 70 dietary preload (DIET) and peptide infusion (INFUSION) studies in lean healthy adults that reported outcomes of CCK, GLP-1 and PYY. DIET studies were acute preload interventions. INFUSION studies showed that minimum increase required to suppress ad libitum energy intake for CCK, GLP-1 and PYY was 3.6-, 4.0- and 3.1-fold, respectively, achieved through DIET in only 29%, 0% and 8% of interventions. Whether circulating ‘thresholds’ of peptide concentration likely required for behavioural change can be achieved through diet is questionable. As yet, no individual or group of peptides can be measured in blood to reliably predict feelings of hunger and food intake. Developing foods that successfully target enhanced secretion of GI-origin ‘satiety’ peptides for weight loss remains a significant challenge.

Safety and efficacy of antihyperglycaemic agents in diabetic kidney disease

Diabetic kidney disease (DKD) is the major contributor to the mortality and the financial burden of diabetes, accounting for approximately 50% of the cases of end-stage renal disease (ESRD) in the developed world. Several studies have already demonstrated that achieving blood pressure targets in DKD with agents blocking the renin-angiotensin system confer superior renoprotection when compared to other agents. However, the effects on renal outcomes of antihyperglycaemic agents in these patients have not been reported or studied broadly until recent years. The intent of this article is to review the available data on safety, efficacy, impact on renal outcomes and pathophysiology implications of the most utilized antihyperglycaemic agents in DKD/ESRD.

Long-term observational study on the impact of GLP-1R agonists on lung function in diabetic patients

INTRODUCTION

Preclinical research suggests a role of Glucagon Like Peptide-1 Receptors (GLP-1R) on the regulation of human bronchial tone. We investigated the effect of GLP-1R agonists on lung function of Type 2 Diabetes Mellitus (T2DM) population without co-existing chronic obstructive respiratory disorders.

METHODS

This was a prospective cohort study that examined change in lung function measurements over two years of T2DM patients (n = 32) treated with metformin monotherapy (control cohort), metformin plus GLP-1R agonists (GLP-1R agonists cohort), or metformin plus insulin (insulin cohort).

RESULTS

After 24 months of treatment, the forced expiratory volume in 1 s (FEV₁) significantly (p < 0.05) increased from baseline in the GLP-1R agonists cohort (218 ml [95%CI 88-246]), but not in the control and insulin cohorts (94 ml [95%CI -28 - 216] and 26 ml [95%CI -174 - 226], respectively; p > 0.05 vs. baseline). The average increase in FEV₁ in the GLP-1R agonists cohort was significantly greater than that in the control and insulin cohorts (delta: 110 ml [95%CI 18-202] and 177 ml [95%CI 85-270], respectively, p < 0.05). The forced vital capacity (FVC) also increased significantly more in the GLP-1R agonists cohort than in the control and insulin cohorts (overall delta FVC: 183 ml [95%CI 72-295], p < 0.05). The maximal expiratory flow at 50-75% significantly (p < 0.05) improved from baseline in the GLP-1R agonists cohort, but not in the control and insulin cohorts (p > 0.05).

CONCLUSION

Our preliminary results suggest a potential new therapeutic perspective to treat airway disorders with GLP-1R agonists.

Rational Design of Hybrid Peptides: A Novel Drug Design Approach

Peptides play crucial roles in various physiological and pathological processes. Consequently, the investigation of peptide-based drugs is a highlight in the research and development of new drugs. However, natural peptides are not always ideal choices for clinical application due to their limited number and sometimes cytotoxicity to normal cells. Aiming to gain stronger or specific or novel biological effects and overcome the disadvantages of natural peptides, artificial hybrid peptides have been designed by combining the sequence of two or more different peptides with varied biological functions. Compared to natural peptides, hybrid peptides have shown better therapeutic potentials against bacteria, tumors, and metabolic diseases. In this review, design strategies, structure features and recent development of hybrid peptides are summarized; future directions for the research and development of hybrid peptide drugs are also discussed.

Weight loss variability with SGLT2 inhibitors and GLP-1 receptor agonists in type 2 diabetes mellitus and obesity: Mechanistic possibilities

We are facing a global epidemic of obesity and type 2 diabetes. Weight loss, in the context of obesity and type 2 diabetes, may improve glycaemic control and weight-related comorbidities, and in some cases, induce diabetes remission. Although lifestyle-based weight loss strategies may be initially successful, most are not effective long-term. There is an increasing need to consider pharmacological approaches to assist weight loss in diabetes-obesity. Older glucose-lowering agents may cause weight gain, whereas the newer drug classes, sodium-glucose co-transporter 2 inhibitors (SGLT2i) and glucagon-like peptide receptor agonists (GLP-1 RAs), concomitantly target weight loss and glycaemic control. Clinical trial data suggest that both SGLT2i and GLP1 RAs cause a mean weight loss of approximately 2 to 3 kg but real-world evidence and clinical experience suggests a significant heterogeneity in the magnitude of the weight loss (GLP-1 RAs) or the magnitude of the actual weight loss is significantly less than anticipated (SGLT2i). Why do some individuals lose more weight than others in response to these pharmacological treatments? This review will first explore mechanisms by which body weight is regulated through control of energy balance and its dysregulation in obesity, and then consider how these mechanisms may be modulated therapeutically with SGLT2i and GLP1 RAs.

The effects of licogliflozin, a dual SGLT1/2 inhibitor, on body weight in obese patients with or without diabetes

BACKGROUND

There is an unmet need for a safer and more effective treatment for obesity. This study assessed the effects of licogliflozin, a dual inhibitor of sodium-glucose co-transporter (SGLT) 1/2, on body weight, metabolic parameters and incretin hormones in patients with type 2 diabetes mellitus (T2DM) and/or obesity.

METHODS

Patients with obesity (BMI, 35-50 kg/m² ) were enrolled into a 12-week study (N = 88; licogliflozin 150 mg q.d.). Patients with T2DM were enrolled into a second, two-part study, comprising a single-dose cross-over study (N = 12; 2.5 - 300 mg) and a 14-day dosing study (N = 30; 15 mg q.d). Primary endpoints included effects on body weight, effects on glucose, safety and tolerability. Secondary endpoints included urinary glucose excretion (UGE₂₄ ) and pharmacokinetics, while exploratory endpoints assessed the effects on incretin hormones (total GLP-1, PYY_3-36 , and GIP), insulin and glucagon.

RESULTS

Treatment with licogliflozin 150 mg q.d. for 12 weeks in patients with obesity significantly reduced body weight by 5.7% vs placebo (P < 0.001) and improved metabolic parameters such as significantly reduced postprandial glucose excursion (21%; P < 0.001), reduced insulin levels (80%; P < 0.001) and increased glucagon (59%; P < 0.001). In patients with T2DM, a single dose of licogliflozin 300 mg in the morning prior to an oral glucose tolerance test (OGTT) remarkably reduced glucose excursion by 93% (P < 0.001; incremental AUC_0-4h ) and suppressed insulin by 90% (P < 0.01; incremental AUC_0-4h ). Treatment with licogliflozin 15 mg q.d. for 14 days reduced 24-hour average glucose levels by 26% (41 mg/dL; P < 0.001) and increased UGE₂₄ to 100 g (P < 0.001) in patients with T2DM. In addition, this treatment regimen significantly increased total GLP-1 by 54% (P < 0.001) and PYY_3-36 by 67% (P < 0.05) post OGTT vs placebo, while significantly reducing GIP levels by 53% (P < 0.001). Treatment with licogliflozin was generally safe and well tolerated. Diarrhea (increased numbers of loose stool) was the most common adverse event in all studies (90% with licogliflozin vs 25% with placebo in the 12-week study), while a lower incidence of flatulence, abdominal pain and abdominal distension (25%-43% with licogliflozin vs 9%-11% with placebo in the 12-week study) were among the other gastrointestinal events reported.

CONCLUSION

Licogliflozin treatment (1-84 days) leads to significant weight loss and favourable changes in a variety of metabolic parameters and incretin hormones. Dual inhibition of SGLT1/2 with licogliflozin in the gut and kidneys is an attractive strategy for treating obesity and diabetes.

Evaluating the long-term cost-effectiveness of fixed-ratio combination insulin degludec/liraglutide (IDegLira) for type 2 diabetes in Spain based on real-world clinical evidence

AIM

To evaluate the long-term cost-effectiveness of fixed-ratio combination insulin degludec/liraglutide (IDegLira) versus comparator regimens for type 2 diabetes in Spain, based on real-world evidence.

MATERIALS AND METHODS

Clinical data were taken from the European Xultophy Treatment Retrospective Audit (EXTRA) real-world evidence study in which patients failing to meet glycaemic targets were switched to IDegLira. Baseline regimens (prior to IDegLira treatment) were categorized as: multiple daily insulin injections (MDI; 28%); glucagon-like peptide-1 (GLP-1) receptor agonists in combination with insulin (24%); basal insulin (19%); GLP-1 receptor agonists (10%); and non-injectable medications (19%). The IQVIA CORE Diabetes Model was used to project long-term outcomes for patients switching to IDegLira or continuing their baseline regimens (excluding non-injectable regimens). Costs were accounted from a Spanish National Health System perspective. Future costs and clinical benefits were discounted at 3% annually and sensitivity analyses were performed.

RESULTS

IDegLira was projected to reduce the incidence of diabetes-related complications and improve quality-adjusted life expectancy versus all four comparators. IDegLira reduced direct medical costs versus GLP-1 receptor agonists in combination with insulin, and versus GLP-1 receptor agonist therapy, and was therefore considered dominant (cost saving while improving outcomes). IDegLira was found to be cost-effective versus MDI and basal insulin with incremental cost-effectiveness ratios of EUR 3013 per quality-adjusted life-year (QALY) gained and EUR 6890 per QALY gained, respectively.

CONCLUSIONS

Long-term projections based on real-world evidence indicated that IDegLira is likely to improve clinical outcomes and reduce costs or be cost-effective compared with other injectable regimens in people with type 2 diabetes in Spain.

Intensification to injectable therapy in type 2 diabetes: mixed methods study (protocol)

BACKGROUND

In the UK, type 2 diabetes mellitus (T2D) is largely managed in primary care. Delay in the intensification to injectable therapy, a form of clinical inertia, is associated with worse glycaemic control. UK general practice is highly computerised, with care being recorded on computerised medical record systems; this allows for quantitative analysis of clinical care but not of the underpinning decision-making process. The aim of this study is to investigate perceptions of patients and clinicians in primary care on the initiation of injectable therapies in T2D, and the context within which those decisions are made.

METHODS

This is a mixed methods study, taking a "realist evaluation" approach. The qualitative components comprise focus groups, interviews, and video recordings of simulated surgeries; the quantitative analysis: an overview of participating practices, elements of the video recording, and an online survey. We will recruit primary care clinicians (general practitioners and nurses) and patients from a representative sample of practices within the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) network. Participants will be patients with T2D, and primary care clinicians. Focus groups and semi-structured interviews will be recorded, transcribed verbatim and analysed using Framework Analysis. The simulated surgeries will include cases that might be escalated to injectable therapy. The consultation will be reviewed using the Calgary-Cambridge model to assess communication and determination of adherence to national prescribing guidelines. We will conduct multi-channel video recording including screen capture, clinician and patient facial expressions, wide angle view of the consultation, and the computerised medical record screen. This allows annotation and qualitative analysis of the video recordings, and statistical analyses for the quantitative data. We will also conduct an online survey of primary care clinicians' attitudes to, and perceptions of, initiation of injectable therapies, which will be analysed using summary statistics.

DISCUSSION

Results aim to provide a detailed insight into the dynamic two-way decision-making process underpinning use of injectable therapy for T2D. The study will provide insights into clinical practice and enable the development of training, interventions and guidelines that may facilitate, where appropriate, the intensification to injectable therapy.

Pleiotropic effects of liraglutide in patients with type 2 diabetes and moderate renal impairment: Individual effects of treatment

Liraglutide has pleiotropic effects favouring cardiovascular and renal risks. We investigated individual responses to liraglutide in six cardio-renal risk factors to examine whether responses in one risk factor are associated with changes in other risk factors (cross-dependency). We performed secondary analysis of the LIRA-RENAL trial (n = 279) in type 2 diabetes. HbA1c, body weight, systolic blood pressure (SBP)_, low density lipoprotein (LDL)-cholesterol, urine albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) were measured at baseline and after 26 weeks of liraglutide/placebo treatment: "Good responders" had a change within the best quartile. In the liraglutide-treated group, good HbA1c responders showed similar changes in other risk factors analysed to low responders (P ≥ 0.17). Good body weight responders had a larger reduction in HbA1c than low body weight responders (-1.6 ± 0.94 vs. -1.0 ± 0.82%; P = 0.003), but similar changes in the other risk factors (P ≥ 0.11). Good and low responders in SBP, UACR, LDL-cholesterol or eGFR showed similar changes in other risk factors (P ≥ 0.07). Treatment response to liraglutide is largely individual; aside from an association between body weight and HbA1c reduction, there are no obvious cross-dependencies in risk factor response.

Current treatments for obesity

Obesity is a major health and economic crisis facing the modern world. It is associated with excess mortality and morbidity and is directly linked to common conditions such as type 2 diabetes mellitus, coronary heart disease and sleep apnoea. The management of obesity and its associated complications has evolved in recent years, with a shift towards more definitive strategies such as bariatric surgery. This review encompasses the dietary, pharmacological and surgical strategies currently available for the management of obesity.

Short-term monotherapy with Liraglutide for weight management: A case study

BACKGROUND

Liraglutide 3 mg was approved by the FDA as an antiobesity drug. A recent study reported that short-term treatment with Liraglutide (20.0 ± 6.4 days) reduces body weight.

CASE PRESENTATION

A 35-year-old male not having any medical illness was presented for medical weight-loss management. He was taking Liraglutide (Saxenda) by SC solution multidose pen 0.6 mg in the first week, 1.2 mg in the second week, 1.8 mg in the third week, 2.4 mg in the fourth week, and 3.0 mg in the fifth week, i.e. 0.6-mg dose increase per week. During the treatment period, he was maintained on low-calorie diet, which was not exceeded 1,500 calories/day. During the treatment period, he was on the mild exercise of walking 45 min three times per week. His initial anthropometric measurements include a weight of 118 kg, height 171 cm, and body mass index 40.4.

CONCLUSION

Short-term (05 weeks) monotherapy with Liraglutide with restricted-calorie diet and mild exercise significantly reduces the weight by 13.55%.

Effects of exenatide and liraglutide on postchallenge glucose disposal in individuals with normal glucose tolerance

PURPOSE

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are categorized as short- or long-acting types, but information regarding differences in the effects of these two types on postprandial glucose disposal has been limited. We have now investigated the effects of exenatide and liraglutide (short- and long-acting GLP-1RAs, respectively) on glucose disposal during an oral glucose tolerance test (OGTT).

METHODS

Fourteen healthy volunteers with normal glucose tolerance underwent three OGTTs, which were performed without pharmacological intervention or after a single administration of exenatide or liraglutide at 30 min and 10 h, respectively, before test initiation. The three OGTTs were performed with intervals of at least 7 days between successive tests and within a period of 2 months.

RESULTS

Exenatide, but not liraglutide, markedly decelerated the peak of both plasma glucose and serum insulin levels during the OGTT, with the peaks of both glucose and insulin concentrations occurring at 150 min after test initiation with exenatide compared with 30 min in the control condition or with liraglutide. Exenatide and liraglutide reduced the area under the curve for plasma glucose levels during the OGTT by similar extents, whereas that for serum insulin levels was reduced only by exenatide.

CONCLUSIONS

Our results suggest that exenatide decelerates the increase in plasma glucose levels through inhibition of glucose absorption and that it exerts an insulin-sparing action after glucose challenge.

Nonglycemic Outcomes of Antidiabetic Medications

IN BRIEF The number of medications used to treat diabetes has increased dramatically in the past 15 years. With so many options that have shown significant A1C improvement, it is important to consider side effects, precautions, and additional benefits these agents may offer. This article is a review of some of the most compelling literature available on the nonglycemic benefits of sulfonylureas, thiazolidinediones, biguanides, glucagon-like peptide 1 receptor agonists, dipeptidyl peptidase 4 inhibitors, and sodium-glucose cotransporter 2 inhibitors. Other classes of antihyperglycemic agents, such as dopamine agonists, meglitinides, and amylin agonists, are not discussed in this article.

The Effects of Hypoglycemic Agents on Non-alcoholic Fatty Liver Disease: Focused on Sodium-Glucose Cotransporter 2 Inhibitors and Glucagon-Like Peptide-1 Receptor Agonists

The only known, effective intervention for non-alcoholic fatty liver disease (NAFLD) is weight loss, and there is no approved pharmacotherapy. Recently, new hypoglycemic agents, such as sodium-glucose cotransporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RAs), and their effects on NAFLD have received substantial interest. Herein, we review the currently available human studies regarding the effects of SGLT2 inhibitors and GLP-1RAs on NAFLD/non-alcoholic steatohepatitis in patients with type 2 diabetes mellitus, and we describe the possible mechanisms explaining the positive effects of these agents on NAFLD.

Crosstalk between gut microbiota and antidiabetic drug action

Type 2 diabetes (T2D) is a disorder characterized by chronic inflated blood glucose levels (hyperglycemia), at first due to insulin resistance and unregulated insulin secretion but with tendency towards global spreading. The gut microbiota is recognized to have an influence on T2D, although surveys have not formed a clear overview to date. Because of the interactions between gut microbiota and host homeostasis, intestinal bacteria are believed to play a large role in various diseases, including metabolic syndrome, obesity and associated disease. In this review, we highlight the animal and human studies which have elucidated the roles of metformin, α-glucosidase inhibitors, glucagon-like peptide-1 agonists, peroxisome proliferator-activated receptors γ agonists, inhibitors of dipeptidyl peptidase-4, sodium/glucose cotransporter inhibitors, and other less studied medications on gut microbiota. This review is dedicated to one of the most widespread diseases, T2D, and the currently used antidiabetic drugs and most promising new findings. In general, the gut microbiota has been shown to have an influence on host metabolism, food consumption, satiety, glucose homoeostasis, and weight gain. Altered intestinal microbiota composition has been noticed in cardiovascular diseases, colon cancer, rheumatoid arthritis, T2D, and obesity. Therefore, the main effect of antidiabetic drugs is on the microbiome composition, basically increasing the short-chain fatty acids-producing bacteria, responsible for losing weight and suppressing inflammation.

Resistance Exercise Training Attenuates the Loss of Endogenous GLP-1 Receptor in the Hypothalamus of Type 2 Diabetic Rats

The aim of this study was to investigate the effects of resistance exercise training on hypothalamic GLP-1R levels and its related signaling mechanisms in T2DM. The animals were separated into three groups: a non-diabetic control (CON), diabetic control (DM), and diabetic with resistance exercise (DM + EXE) group. The resistance exercise training group performed ladder climbing (eight repetitions, three days per week for 12 weeks). Body weight was slightly lower in the DM + EXE group than the DM group, but difference between the groups was not significant. Food intake and glucose were significantly lower in the DM + EXE group than in the DM group. The blood insulin concentration was significantly higher and glucagon was significantly lower in the DM + EXE group. The DM + EXE group in the hypothalamus showed significant increases in GLP-1R mRNA, protein kinase A (PKA), glucose transporter 2 (GLUT2), and protein kinase B (AKT) and significant decrease in protein kinase C-iota (PKC-iota). Antioxidant enzymes and apoptosis factors were significantly improved in the DM + EXE group compared with the DM group in the hypothalamus. The results suggest that resistance exercise contributes to improvements the overall health of the brain in diabetic conditions.

Effects of liraglutide on obesity-associated functional hypogonadism in men

Lifestyle measures (LSMs) should be the first-line approach offered for obesity-related functional hypogonadism (FH). When LSMs fail, the role of testosterone replacement treatment (TRT) is unclear. GLP1 receptor agonist liraglutide is linked to progressive and sustained weight loss. A potential direct impact of GLP1 on hypothalamus-pituitary-testicular (HPT) axis was reported in animal models. We aimed to compare the effects of liraglutide and TRT on FH in obese men that had been poor responders to LSM, by means of reversal of FH and weight reduction. We designed a 16-week prospective randomized open-label study with 30 men (aged 46.5 ± 10.9 years, BMI 41.2 ± 8.4 kg/m2, mean ± s.d.) that were randomized to liraglutide 3.0 mg QD (LIRA) or 50 mg of 1% transdermal gel QD (TRT). Sexual function and anthropometric measures were assessed. Fasting blood was drawn for determination of endocrine and metabolic parameters followed by OGTT. Model-derived parameters including HOMAIR and calculated free testosterone (cFT) were calculated. Total testosterone significantly increased in both arms (+5.9 ± 7.2 in TRT vs +2.6 ± 3.5 nmol/L in LIRA) and led to improved sexual function. LIRA resulted in a significant increase of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (P < 0.001 for between-treatment effect). Subjects treated with LIRA lost on average 7.9 ± 3.8 kg compared with a 0.9 ± 4.5 kg loss in TRT (P < 0.001). Metabolic syndrome was resolved in two patients in LIRA and in no subjects in TRT. Liraglutide was superior to TRT in improving an overall health benefit in men with obesity-associated FH after LSM failed.

Randomised, phase 1, dose-finding study of MEDI4166, a PCSK9 antibody and GLP-1 analogue fusion molecule, in overweight or obese patients with type 2 diabetes mellitus

AIMS/HYPOTHESIS

Cardiovascular disease is the leading cause of morbidity and mortality in people with type 2 diabetes. MEDI4166 is a proprotein convertase subtilisin/kexin type 9 (PCSK9) antibody and glucagon-like peptide-1 (GLP-1) analogue fusion molecule designed to treat patients with type 2 diabetes who are at risk for cardiovascular disease. In this completed, first-in-human study, we evaluated the safety and efficacy of single or multiple doses of MEDI4166 in participants with type 2 diabetes.

METHODS

In this phase 1 study that was conducted across 11 clinics in the USA, eligible adults had type 2 diabetes, a BMI of ≥25 kg/m² to ≤42 kg/m², and LDL-cholesterol levels ≥1.81 mmol/l. Participants were randomised 3:1 to receive MEDI4166 or placebo using an interactive voice/web response system, which blinded all participants, investigators and study site personnel to the study drug administered. In 'Part A' of the study, five cohorts of participants received a single s.c. injection of MEDI4166 at 10 mg, 30 mg, 100 mg, 200 mg or 400 mg, or placebo. 'Part B' of the study consisted of three cohorts of participants who received an s.c. dose of MEDI4166 once weekly for 5 weeks at 50 mg, 200 mg or 400 mg, or placebo. The primary endpoint in Part A was safety. The co-primary endpoints in Part B were change in LDL-cholesterol levels and area under the plasma glucose concentration-time curve (AUC_0-4h) post-mixed-meal tolerance test (MMTT) from baseline to day 36. The pharmacokinetics and immunogenicity of MEDI4166 were also evaluated.

RESULTS

MEDI4166 or placebo was administered to n = 30 or n = 10 participants, respectively, in Part A of the study, and n = 48 or n = 15 participants, respectively, in Part B. The incidence of treatment-emergent adverse events (TEAEs) were comparable between MEDI4166 and placebo in both Part A (60% vs 50%) and Part B (79% vs 87%) of the study. Common TEAEs with MEDI4166 included injection-site reactions, diarrhoea and headache; there was no evidence for dose-related increases in TEAEs. In Part B of the study, at all tested doses of MEDI4166, there was a significant decrease in LDL-cholesterol levels vs placebo (least squares mean [95% CI]; MEDI4166 50 mg, -1.25 [-1.66, -0.84]; MEDI4166 200 mg, -1.97 [-2.26, -1.68]; MEDI4166 400 mg, -1.96 [-2.23, -1.70]; placebo, -0.03 [-0.35, 0.28]; all p < 0.0001). However, there were no clinically relevant reductions or significant differences between MEDI4166 vs placebo in glucose AUC_0-4h post-MMTT (least squares mean [95% CI]; MEDI4166 50 mg, -10.86 [-17.69, -4.02]; MEDI4166 200 mg, -4.23 [-8.73, 0.28]; MEDI4166 400 mg, -2.59 [-7.14, 1.95]; placebo, -4.84 [-9.95, 0.28]; all p > 0.05). MEDI4166 was associated with a pharmacokinetic profile supportive of weekly dosing and an overall treatment-induced anti-drug antibody-positive rate of 22%.

CONCLUSIONS/INTERPRETATION

MEDI4166 was associated with an acceptable tolerability profile and significantly decreased LDL-cholesterol levels in a dose-dependent manner in overweight or obese patients with type 2 diabetes. However, there were no significant reductions in postprandial glucose levels at any dose of MEDI4166.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02524782 FUNDING: This study was funded by MedImmune LLC, Gaithersburg, MD, USA.

Effects of liraglutide, metformin and gliclazide on body composition in patients with both type 2 diabetes and non-alcoholic fatty liver disease: A randomized trial

AIMS/INTRODUCTION

To compare the effects of gliclazide, liraglutide and metformin on body composition in patients with type 2 diabetes mellitus with non-alcoholic fatty liver disease.

MATERIALS AND METHODS

A total of 85 patients were randomly allocated to receive gliclazide (n = 27), liraglutide (n = 29) or metformin (n = 29) monotherapy for 24 weeks. Body composition was measured using dual-energy X-ray absorptiometry.

RESULTS

Liraglutide and metformin reduced total, trunk, limb, android and gynoid fat mass; this also led to weight reduction. However, gliclazide treatment produced no significant changes in weight or fat mass, likely because reductions in fat mass were concomitant with increases in lean tissue mass. Blood glucose concentrations and glycated hemoglobin levels improved in all treatment arms; levels of the latter were lower in patients treated with liraglutide and metformin. Serum alanine aminotransferase concentrations decreased in all treatment arms, whereas serum aspartate aminotransferase concentrations were reduced only by liraglutide and metformin. In all patients, weight loss and total, trunk, limb, and android fat mass reductions were positively correlated with decreases in serum alanine aminotransferase and aspartate aminotransferase levels, whereas reductions in waist circumference were positively correlated with lower serum alanine aminotransferase levels.

CONCLUSIONS

Compared with gliclazide, liraglutide and metformin monotherapies result in greater weight loss, reductions in body fat mass, and better blood glucose control among type 2 diabetes mellitus patients with non-alcoholic fatty liver disease. Reductions in weight, fat mass and waist circumference favorably affect hepatic function.

The pathogenesis of obesity

Body fat mass increases when energy intake exceeds energy expenditure. In the long term, a positive energy balance will result in obesity. The worldwide prevalence of obesity has increased dramatically, posing a serious threat to human health. Therefore, insight in the pathogenesis of obesity is important to identify novel prevention and treatment strategies. This review describes the physiology of energy expenditure and energy intake in the context of body weight gain in humans. We focus on the components of energy expenditure and the regulation of energy intake. Finally, we describe rare monogenetic causes leading to an impairment in central regulation of food intake and obesity.

Effect of liraglutide on ambulatory blood pressure in patients with hypertension and type 2 diabetes: A randomized, double-blind, placebo-controlled trial

AIMS

To assess the effect of liraglutide on 24-hour ambulatory blood pressure and heart rate in patients with hypertension (pre- and stage 1 hypertension) and inadequately controlled Type 2 diabetes (glycated haemoglobin 7%-10% [53-86 mmol/mol]).

MATERIALS AND METHODS

Eligible patients for this investigator-initiated, parallel-group, randomized, double-blind trial were on stable background antihyperglycaemic therapy excluding insulin, glucagon-like peptide-1 receptor agonists and dipeptidyl-peptidase-4 inhibitors. Participants were centrally randomized in a 1:1 ratio to daily liraglutide 0.6 mg, titrated to 1.2 mg after the first week, or placebo for 5 weeks. The primary outcome was change in 24-hour ambulatory systolic blood pressure (SBP), and secondary outcomes included change in ambulatory diastolic blood pressure (DBP) and heart rate. We also assessed renal sodium handling.

RESULTS

Of 87 patients assessed for eligibility, 62 (66.1% men) with a mean age of 60.2 years were randomized to liraglutide (n = 31) or placebo (n = 31). All participants received background therapy with metformin, whilst 35.5% were treated concomitantly with sulphonylureas and 14.5% with pioglitazone. Compared with placebo, liraglutide reduced 24-hour SBP by -5.73 mm Hg (95% confidence interval [CI] -9.81 to -1.65) and had a neutral effect on 24-hour DBP (mean difference - 1.42 mm Hg; 95% CI -4.25 to 1.40), whilst increasing 24-hour heart rate by 6.16 beats/min (95% CI 3.25 to 9.07). Findings were consistent for daytime and night-time measurements. Liraglutide did not increase urine sodium excretion.

CONCLUSION

Based on 24-hour ambulatory measurements, short-term treatment with liraglutide had a favourable effect on SBP whilst increasing heart rate.

Pharmacotherapy of obesity: Available medications and drugs under investigation

Obesity is a chronic disease with a continuously rising prevalence that currently affects more than half a billion people worldwide. Energy balance and appetite are highly regulated via central and peripheral mechanisms, and weight loss triggers a homeostatic response leading to weight regain. Lifestyle and behavioral modifications are the cornerstones of obesity management; however, they often fail to achieve or sustain long-term weight loss. Pharmacotherapy added onto lifestyle modifications results in an additional, albeit limited, weight reduction. Regardless, this weight reduction of 5-10% conveys multiple cardiovascular and metabolic benefits. In this review, evidence on the food and drug administration (FDA)-approved medications, i.e., orlistat, lorcaserin, phentermine/topiramate, liraglutide and naltrexone/bupropion, is summarized. Furthermore, anti-obesity agents in the pipeline for potential future therapeutic use are presented.

Liraglutide and its Neuroprotective Properties-Focus on Possible Biochemical Mechanisms in Alzheimer's Disease and Cerebral Ischemic Events

Liraglutide is a GLP-1 analog (glucagon like peptide-1) used primarily in the treatment of diabetes mellitus type 2 (DM2) and obesity. The literature starts to suggest that liraglutide may reduce the effects of ischemic stroke by activating anti-apoptotic pathways, as well as limiting the harmful effects of free radicals. The GLP-1R expression has been reported in the cerebral cortex, especially occipital and frontal lobes, the hypothalamus, and the thalamus. Liraglutide reduced the area of ischemia caused by MCAO (middle cerebral artery occlusion), limited neurological deficits, decreased hyperglycemia caused by stress, and presented anti-apoptotic effects by increasing the expression of Bcl-2 and Bcl-xl proteins and reduction of Bax and Bad protein expression. The pharmaceutical managed to decrease concentrations of proapoptotic factors, such as NF-κB (Nuclear Factor-kappa β), ICAM-1 (Intercellular Adhesion Molecule 1), caspase-3, and reduced the level of TUNEL-positive cells. Liraglutide was able to reduce the level of free radicals by decreasing the level of malondialdehyde (MDA), and increasing the superoxide dismutase level (SOD), glutathione (GSH), and catalase. Liraglutide may affect the neurovascular unit causing its remodeling, which seems to be crucial for recovery after stroke. Liraglutide may stabilize atherosclerotic plaque, as well as counteract its early formation and further development. Liraglutide, through its binding to GLP-1R (glucagon like peptide-1 receptor) and consequent activation of PI3K/MAPK (Phosphoinositide 3-kinase/mitogen associated protein kinase) dependent pathways, may have a positive impact on Aβ (amyloid beta) trafficking and clearance by increasing the presence of Aβ transporters in cerebrospinal fluid. Liraglutide seems to affect tau pathology. It is possible that liraglutide may have some stem cell stimulating properties. The effects may be connected with PKA (phosphorylase kinase A) activation. This paper presents potential mechanisms of liraglutide activity in conditions connected with neuronal damage, with special emphasis on Alzheimer's disease and cerebral ischemia.

Possible mechanisms of direct cardiovascular impact of GLP-1 agonists and DPP4 inhibitors

Diabetes mellitus is a leading cause of cardiovascular morbidity and mortality worldwide. Traditional antidiabetic therapies targeting hyperglycemia reduce diabetic microvascular complications but have minor effects on macrovascular complications, including cardiovascular disease. Instead, cardiovascular complications are improved by antidiabetic medications (metformin) and other therapies (statins, antihypertensive medications) ameliorating insulin resistance and other associated metabolic abnormalities. Novel classes of antidiabetic drugs have proven efficacious in improving glycemia, while at the same time exert beneficial effects on pathophysiologic mechanisms of diabetes-related cardiovascular disease. In the present review, we will present current evidence of the cardiovascular effects of two new classes of antidiabetic medications, glucagon-like peptide 1 (GLP-1) agonists and dipeptidyl peptidase-4 (DPP4) inhibitors, focusing from mechanistic preclinical and clinical investigation to late-phase clinical testing.

Glucagon-like peptide-1 receptor agonists for antipsychotic-associated cardio-metabolic risk factors: A systematic review and individual participant data meta-analysis

AIMS

To evaluate if glucagon-like peptide-1 receptor agonists (GLP-1RAs) reduce antipsychotic-associated body weight gain in patients with schizophrenia, when compared to controls.

MATERIALS AND METHODS

We systematically searched PubMed/EMBASE/PsycINFO/Cochrane using the search terms '(antipsychotic and GLP-1RA)'. Individual participant data from studies randomizing patients to GLP-1RA or control were meta-analysed. The primary outcome was difference in body weight between GLP-1RA and control; secondary outcomes included cardio-metabolic variables and adverse drug reactions (ADRs). Multiple linear regression was conducted including sex, age, psychosis severity, metabolic variable, ADRs, and GLP-1RA agent.

RESULTS

Three studies (exenatide once-weekly = 2; liraglutide once-daily = 1) provided participant-level data (n = 164, age = 40.0 ± 11.1 years, body weight = 105.8 ± 20.8 kg). After 16.2 ± 4.0 weeks of treatment, body weight loss was 3.71 kg (95% CI = 2.44-4.99 kg) greater for GLP-1RA versus control (p < 0.001), number-needed-to-treat ≥5% body weight loss = 3.8 (95% CI = 2.6-7.2). Waist circumference, body mass index, HbA1c, fasting glucose and visceral adiposity were each significantly lower with GLP-1RA. Sex, age, psychosis severity, nausea, any ADR, and GLP-1RA agent did not significantly impact outcomes. Body weight loss with GLP-1RAs was greater for clozapine/olanzapine-treated patients (n = 141) than other antipsychotics (n = 27) (4.70 kg, 95% CI = 3.13-6.27 vs. 1.5 kg, 95% CI = -1.47-4.47) (p < 0.001). Nausea was more common with GLP-1RAs than control (53.6% vs. 27.5%, p = 0.002, number-needed-to-harm = 3.8).

CONCLUSION

GLP-1RAs are effective and tolerable for antipsychotic-associated body weight gain, particularly clozapine/olanzapine-treated patients. With few included patients, further studies are required before making routine use recommendations for GLP-1RAs.

Emerging hormonal-based combination pharmacotherapies for the treatment of metabolic diseases

Obesity and its comorbidities, such as type 2 diabetes mellitus and cardiovascular disease, constitute growing challenges for public health and economies globally. The available treatment options for these metabolic disorders cannot reverse the disease in most individuals and have not substantially reduced disease prevalence, which underscores the unmet need for more efficacious interventions. Neurobiological resilience to energy homeostatic perturbations, combined with the heterogeneous pathophysiology of human metabolic disorders, has limited the sustainability and efficacy of current pharmacological options. Emerging insights into the molecular origins of eating behaviour, energy expenditure, dyslipidaemia and insulin resistance suggest that coordinated targeting of multiple signalling pathways is probably necessary for sizeable improvements to reverse the progression of these diseases. Accordingly, a broad set of combinatorial approaches targeting feeding circuits, energy expenditure and glucose metabolism in concert are currently being explored and developed. Notably, several classes of peptide-based multi-agonists and peptide-small molecule conjugates with superior preclinical efficacy have emerged and are currently undergoing clinical evaluation. Here, we summarize advances over the past decade in combination pharmacotherapy for the management of obesity and type 2 diabetes mellitus, exclusively focusing on large-molecule formats (notably enteroendocrine peptides and proteins) and discuss the associated therapeutic opportunities and challenges.

Beneficial Effects of GLP-1 Agonist in a Male With Compulsive Food-Related Behavior Associated With Autism

Individuals with autism spectrum disorder (ASD) frequently display intensely repetitive, restricted thoughts, and behaviors. These behaviors have similarities to compulsions and/or obsessions in obsessive compulsive disorder (OCD) and are primarily treated with behaviourally-based interventions and serotonin uptake inhibitors (SSRIs). Due to the lack of treatment responses in many cases, however, new treatments are being sought. Here we report beneficial effects of treatment with liraglutide, a glucagon-like peptide-1 (GLP-1) analog, on severe obsessive food craving, binge eating, weight gain, and behavioral problems in an adolescent male with infantile autism and moderate intellectual impairment. Liraglutide treatment reduced weight and unwanted behavior seemingly by preventing food-related repetitive thoughts and compulsions. Our report provides clinical evidence that GLP-1 signaling pathway may represent a novel target for treating food-related behavioral problems and aggressive behavior in ASD.

A novel dual glucagon-like peptide and glucagon receptor agonist SAR425899: Results of randomized, placebo-controlled first-in-human and first-in-patient trials

AIMS

To evaluate the safety, pharmacokinetics and pharmacodynamics of SAR425899, a novel polypeptide, active as an agonist at both the glucagon-like peptide-1 receptor (GLP-1R) and the glucagon receptor (GCR), in healthy volunteers and in overweight/obese patients with type 2 diabetes (T2D).

METHODS

Subcutaneous administrations of SAR425899 were tested in two randomized, placebo-controlled, double-blind clinical trials. In the first trial, healthy overweight volunteers (body mass index [BMI] 25-30 kg/m² ; n = 32) received single-ascending doses (0.01-0.1 mg) of SAR425899 or placebo. In the second, a multiple-ascending-dose trial (NCT02411825), healthy normal- to overweight volunteers (BMI 20-30 kg/m² ; n = 40) and overweight/obese patients with T2D (BMI 28-42 kg/m² ; n = 36) received daily doses of SAR425899 or placebo over 21 or 28 days, respectively.

RESULTS

The most frequently reported adverse events were gastrointestinal; gastrointestinal side effects were less pronounced in patients with T2D compared with healthy volunteers. SAR425899 significantly reduced levels of fasting plasma glucose (P < 0.05 vs. placebo) and glycated haemoglobin (P < 0.001 versus placebo) in patients with T2D. Additionally, SAR425899 led to reductions in body weight, with a maximal reduction of 5.32 kg in healthy volunteers and 5.46 kg in patients with T2D (P < 0.001 vs. placebo) at end of treatment.

CONCLUSIONS

SAR425899 was well tolerated and led to favourable glycaemic effects in patients with T2D and weight reduction in both healthy volunteers and patients. Whether dual GLP-1R/GCR agonism represents a treatment method that is superior to pure GLP-1R agonists for obesity and diabetes treatment remains to be confirmed.

Predictors of Effectiveness of Glucagon-Like Peptide-1 Receptor Agonist Therapy in Patients with Type 2 Diabetes and Obesity

RATIONALE

It is well known that diabetes mellitus (DM) exacerbates the mechanisms underlying atherosclerosis. Currently, glucagon-like peptide-1 receptor agonists (aGLP-1) have one of the most prominent cardioprotective effects among the antidiabetic agents. However, the treatment with aGLP-1 is effective only in 50-70% of the cases. Taking into account the high cost of these medications, discovery of the predictors of optimal response to treatment is required.

PURPOSE

To identify the predictors of the greater impact of aGLP-1 on HbA1c levels, weight reduction, and improvement in lipid profile.

METHODS

The study group consisted of 40 patients with type 2 DM (T2DM) and obesity who were treated with aGLP-1. The follow-up period was 24 weeks. Patients' evaluation was conducted at baseline and after 24 weeks. In addition, it included the assessment of the hormones involved in glucose and lipid metabolism and appetite regulation.

RESULTS

Patients who have initially higher BMI (body mass index), glycemia, and triglycerides (TG) had better improvement in these parameters undergoing aGLP-1 treatment. In patients with a BMI loss ≥ 5%, GLP-1 and fasting ghrelin levels were higher and ghrelin level in postnutritional status was lower. The HbA1c levels decreased more intensively in participants with higher GLP-1 levels. TG responders had lower baseline fasting glucose-dependent insulinotropic peptide (GIP) and postprandial ghrelin levels.

CONCLUSION

The evaluation of the glycemic control, lipid profile, and GLP-1, GIP, and ghrelin levels are useable for estimating the expected efficacy of aGLP-1.

Liraglutide improves the beta-cell function without increasing insulin secretion during a mixed meal in patients, who exhibit well-controlled type 2 diabetes and coronary artery disease

BACKGROUND

Hyperinsulinemia aggravates insulin resistance and cardio-vascular disease. How the insulinotropic glucagon-like peptide-1 receptor agonist liraglutide in a physiologic post-prandial setting may act on pancreatic alpha and beta-cell function in patients with coronary artery disease (CAD) and type 2 diabetes (T2DM) is less clear.

METHODS

Insulin resistant patients with established CAD and newly diagnosed well-controlled T2DM were recruited to a placebo-controlled, cross-over trial with two treatment periods of 12 weeks and a 2 weeks wash-out period before and in-between. Treatment was liraglutide or placebo titrated from 0.6 mg q.d. to 1.8 mg q.d. within 4 weeks and metformin titrated from 500 mg b.i.d to 1000 mg b.i.d. within 4 weeks. Before and after intervention in both 12 weeks periods insulin, C-peptide, glucose, and glucagon were measured during a meal test. Beta-cell function derived from the oral glucose tolerance setting was calculated as changes in insulin secretion per unit changes in glucose concentration (B_total) and whole-body insulin resistance using ISI_composite.

RESULTS

Liraglutide increased the disposition index [B_total × ISI_composite, by 40% (n = 24, p < 0.001)] compared to placebo. Post-prandial insulin and glucose was reduced by metformin in combination with liraglutide and differed, but not significantly different from placebo, moreover, glucagon concentration was unaffected. Additionally, insulin clearance tended to increase during liraglutide therapy (n = 26, p = 0.06).

CONCLUSIONS

The insulinotropic drug liraglutide may without increasing the insulin concentration reduce postprandial glucose but not glucagon excursions and improve beta-cell function in newly diagnosed and well-controlled T2DM.Trial registration Clinicaltrials.gov ID: NCT01595789.

Real-world GLP-1 RA therapy in type 2 diabetes: A long-term effectiveness observational study

AIMS

To evaluate in a real-world setting the effectiveness and tolerability of available GLP-1 RA drugs in patients with type 2 diabetes after a prolonged follow-up.

MATERIALS AND METHODS

Observational, retrospective, single-centre study in patients starting GLP-1 RA therapy. Change in HbA1c, fasting plasma glucose (FPG) and body mass index (BMI) along with gastrointestinal (GI) adverse events and withdrawal from GLP-1 RA therapy were evaluated. Lack of efficacy of GLP-1 RA therapy according to prespecified goals was also measured.

RESULTS

A total of 735 patients were included, mean age 59.7 years, duration of diabetes 9.01 years, HbA1c 8.18% and BMI 38.56 kg/m2. Average follow-up was 18.97 months (range 4.2-39.09). All HbA1c (0.93%; P < 0.01), FPG (24 mg/dL; P < 0.01) and BMI (1.55 kg/m2; P < 0.05) were significantly reduced from baseline and maintained throughout follow-up, regardless of prescribed GLP-1 RA. GI adverse events were present in 13.81% of patients at first follow-up visit, 37.07% of patients discontinued GLP-1 RA treatment, and 38.63% did not meet efficacy goals.

CONCLUSIONS

In a real-world setting, GLP-1 RA therapy is largely prescribed in severely obese patients with a long-standing and poorly controlled diabetes. All prescribed GLP-1 RAs significantly decreased HbA1c, FPG and BMI. GI adverse events affected a low proportion of patients. Inversely, a high proportion of patients did not meet efficacy goals and/or discontinued GLP-1 RA treatment. Baseline characteristics of patients and lack of adherence may represent important issues underlying differences in effectiveness in real-world studies versus randomized trials.

GLP-1 receptor agonists and cardiovascular outcome trials: An update

Major cardiovascular (CV) outcome trials with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are currently available. These agonists have proven their CV safety, in harmony with the US Food and Drug Administration (FDA) recommendation for antidiabetic drugs. The potential cardioprotective effect of incretin-based therapies is attributed to their multiple non-glycaemic actions in the CV system, including changes in insulin resistance, weight loss, reduction in blood pressure, improved lipid profile and direct effects on the heart and vascular endothelium. Liraglutide, semaglutide and albiglutide have been demonstrated to reduce the risk of major adverse cardiac events (MACE), whereas lixisenatide and extended-release exenatide had a neutral effect. Thus, it is conceivable that there are different drug-specific properties across the class of GLP-1 RAs. In this review, we discuss the results of the five recently published randomised CV outcome trials with GLP-1 RAs, along with the potential differences and the pleiotropic actions of these agents on the CV system.

Systematic review of incretin therapy during peri-operative and intensive care

Background

Glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) are incretin hormones. By lowering blood glucose in a glucose-dependent manner, incretin-based therapies represent a novel and promising intervention to treat hyperglycaemia in hospital settings. We performed a systematic review of the literature for all current applications of incretin-based therapies in the peri-operative and critical care settings.

Methods

We searched MEDLINE, the Cochrane Library, and Embase databases for all randomised controlled trials using exogenous GLP-1, GLP-1 receptor agonists, exogenous GIP and dipeptidyl peptidase IV inhibitors in the setting of adult peri-operative care or intensive care. We defined no comparator treatment. Outcomes of interest included blood glucose, frequency of hypoglycaemia and insulin administration.

Results

Of the 1190 articles identified during the initial literature search, 38 fulfilled criteria for full-text review, and 19 single-centre studies were subsequently included in the qualitative review. Of the 18 studies reporting glycaemic control, improvement was reported in 15, defined as lower glucose concentrations in 12 and as reduced insulin administration (with similar glucose concentrations) in 3. Owing to heterogeneity, meta-analysis was possible only for the outcome of hypoglycaemia. This revealed an incidence of 7.4% in those receiving incretin-based therapies and 6.8% in comparator groups (P = 0.94).

Conclusions

In small, single-centre studies, incretin-based therapies lowered blood glucose and reduced insulin administration without increasing the incidence of hypoglycaemia.

Trial registration

PROSPERO, CRD42017071926.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2197-4) contains supplementary material, which is available to authorized users.

Multiple target tissue effects of GLP-1 analogues on non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH)

Accumulating experimental and clinical evidences over the last decade indicate that GLP-1 analogues have a series of central nervous system and peripheral target tissues actions which are able to significantly influence the liver metabolism. GLP-1 analogues pleiotropic effects proved to be efficacious in T2DM subjects not only reducing liver steatosis and ameliorating NAFLD and NASH, but also in lowering plasma glucose and liver inflammation, improving cardiac function and protecting from kidney dysfunction. While the experimental and clinical data are robust, the precise mechanisms of action potentially involved in these protective multi-target effects need further investigation. Here we present a systematic review of the most recent literature data on the multi-target effects of GLP-1 analogues on the liver, on adipose and muscular tissue and on the nervous system, all capable of influencing significant aspects of the fatty liver disease physiopathology. From this analysis, we can conclude that the multi-target beneficial action of the GLP-1 analogues could explain the positive effects observed in animal and human models on progression of NAFLD to NASH.

Diabetes and obesity. The role of agonists glucagon-like peptide-1 of in the treatment of type 2 diabetes

Significant number of patients with type 2 diabetes mellitus are obese. It is known that even glucose intolerance, as well as diabetes, can lead to vascular complications. At the same time, weight loss can reduce the risk of type 2 diabetes in obese and pre-diabetic patients. According to available data, a significant decrease in the incretin effect is observed in patients with type 2 diabetes and obese individuals. Thus, a decrease in the incretin effect leads to a violation of the insulin response to the intake of carbohydrates, and, consequently, an increase in the level of glucose in the blood. It was also found that the decrease in the incretin effect in patients with type 2 diabetes can be associated with a lower secretion of glucagon-like peptide-1. The interest is represented by groups of antidiabetic drugs capable of regulating glycemia by affecting the secretion of insulin and glucagon, depending on its level. Such drugs include glucagon-like peptide-1 receptor agonists. The article shows the advantage of prolonged action in patients with type 2 diabetes and obesity of the glucagon-like peptide 1 receptor agonists (albiglutide, dulaglutide, exenatide with slow release) dosing 1 time a week.

Effects of exenatide versus insulin glargine on body composition in overweight and obese T2DM patients: a randomized controlled trial

Background

Weight loss, especially fat mass reduction, helps to improve blood glucose control, insulin sensitivity, and β-cell function. This study aimed to compare the effect of exenatide and glargine on body composition in overweight and obese patients with type 2 diabetes (T2DM) who do not achieve adequate glycemic control with metformin.

Methods

We performed a prospective, randomized study of 37 overweight or obese patients with T2DM who had inadequate glycemic control with metformin. The patients were treated with either exenatide or glargine for 16 weeks. Dual-energy X-ray absorptiometry was used to assess body composition.

Results

Post-intervention weight, body mass index (BMI), waist circumference, body mass, and fat mass were lower in patients treated with exenatide, while weight and BMI significantly increased with glargine. Reductions in weight, BMI, body fat mass, and percent fat mass (except for gynoid) were greater with exenatide than with glargine, and percent lean tissue (other than the limbs) increased with exenatide. In all body regions except for the limbs, fat mass decreased with exenatide to a greater extent than lean tissue. Glucose control, insulin resistance, and β-cell function were not different between the treatment groups.

Conclusions

For overweight and obese patients whose T2DM was inadequately controlled with metformin, exenatide and glargine achieved similar improvements in glycemic control, insulin sensitivity, and β-cell function.However, exenatide produced better weight and fat mass reduction, which were beneficial for blood glucose control. Our findings may guide the selection of appropriate drugs for glycemic and weight control.

Trial registration

NCT02325960, registered 25 December 2014.

Endogenous GLP-1 alters postprandial functional connectivity between homeostatic and reward-related brain regions involved in regulation of appetite in healthy lean males: A pilotstudy

AIMS

Peripheral infusion of glucagon-like peptide-1 (GLP-1) can affect brain activity in areas involved in the regulation of appetite, including hypothalamic and reward-related brain regions. In contrast, the physiological role of endogenous GLP-1 in the central regulation of appetite has hardly been investigated.

MATERIALS AND METHODS

This was a randomized, cross-over trial that involved 12 healthy volunteers who received an intragastric (ig) glucose (gluc) load, with or without intravenous (iv) exendin9-39 (ex9-39; specific GLP-1 receptor antagonist). Functional magnetic resonance imaging was used to investigate the effect of endogenous GLP-1 on resting state functional connectivity (rsFC) between homeostatic and reward-related brain regions. Visual analogue scales were used to rate appetite-related sensations. Blood samples were collected for GI hormone measurements.

RESULTS

Administration of iv-ex9-39/ig-gluc induced a significantly higher rsFC, relative to ig-gluc administration, between the hypothalamus and the left lateral orbitofrontal cortex (OFC) as well as the left amygdala (P ≤ .001, respectively). Administration of iv-ex9-39/ig-gluc induced a significantly higher rsFC, relative to ig-gluc administration, between the right nucleus accumbens and the right lateral OFC (P < .001). Administration of iv-ex9-39/ig-gluc induced a significantly lower rsFC, relative to ig-gluc administration, between the midbrain and the right caudate nucleus (P = .001). Administration of ig-gluc significantly decreased prospective food consumption and increased sensations of fullness compared to pre-infusion baseline (P = .028 and P = .019, respectively); these effects were not present in the iv-ex9-39/ig-gluc condition.

CONCLUSIONS

This pilot trial provides preliminary experimental evidence that glucose-induced endogenous GLP-1 affects central regulation of appetite by modulating rsFC in homeostatic and reward-related brain regions in healthy lean male participants in a GLP-1 receptor-mediated fashion.

Safety and efficacy assessment of a GLP-1 mimetic: insulin glargine combination for treatment of feline diabetes mellitus

A commonly used therapeutic strategy for type 2 diabetes mellitus (DM) in humans involves the use of synthetic incretin hormone-based therapies including exenatide, a glucagon-like pepetide-1 hormone agonist. Glucagon-like pepetide-1 agonists can be used alone or as an ancillary therapy with other agents, including insulin and oral antihyperglycemics. Little is known about the role of these therapies for DM in cats. Therefore, the primary objective of this study was to evaluate the safety and efficacy of short-acting exenatide combined with insulin, as compared to placebo and insulin for the treatment of DM in cats. Treatment with exenatide was well tolerated; only 2 cats developed side effects requiring dose reduction. Two cats (25%) went into diabetic remission while receiving exenatide and insulin, whereas remission was not reported during placebo treatment. The average change in the daily exogenous insulin dose was significant (β = -0.56 U/kg, 95% confidence interval, -0.96 to -0.15, P = 0.007), and the dose of insulin administered was lower during exenatide treatment. The average weight loss experienced on exenatide was significantly higher than on placebo (β = 0.65 kg, 95% confidence interval, 0.09-1.21, P = 0.02). There was no significant difference in any of the hormone concentrations evaluated for cats on exenatide vs placebo treatments. Overall, the treatment of diabetic cats with insulin and a fixed dose of exenatide was found to be safe. The weight loss and decreased exogenous insulin requirement experienced with exenatide treatment could be a significant benefit for overweight diabetic cats and warrants further evaluation.

Characteristics of WBN/Kob diabetic fatty rats supplemented with a fructose-rich diet as a metabolic syndrome model: response to a GLP-1 receptor agonist

The incidence of metabolic syndrome is rapidly increasing worldwide, and adequate animal models are crucial for studies on its pathogenesis and therapy. In the search of an adequate experimental model to simulate human metabolic syndrome, the present study was performed to examine the pharmacological response of WBN/Kob-Lepr^fa (WBKDF) rats supplemented with a fructose-rich diet (FRD) to liraglutide, a GLP-1 receptor agonist. Male WBKDF rats fed FRD at 7 weeks of age were divided into 3 groups, and administered liraglutide (75, 300 µg/kg subcutaneously) or saline (control group), once daily for 4 weeks. All rats in the control group became overweight, and developed hyperglycemia, hypertension and dyslipidemia as they aged. The rats given liraglutide exhibited a dose-dependent reduction in body weight, visceral fat content and food intake compared with control rats. In addition, liraglutide suppressed the development of hyperglycemia, hypertension and dyslipidemia. An intravenous glucose tolerance test revealed that liraglutide improved glucose tolerance, insulin secretion and insulin resistance. On histological examination, decreased hepatic fatty degeneration was observed in the liraglutide groups. The present study demonstrated that liraglutide protected against obesity, hyperglycemia, hypertension, dyslipidemia, and hepatic steatosis in WBKDF rats fed FRD, suggesting that WBKDF rats fed FRD may be a useful model to investigate the etiology of human metabolic syndrome.

Comparison of antidiabetic drugs added to sulfonylurea monotherapy in patients with type 2 diabetes mellitus: A network meta-analysis

AIMS

This study aimed to investigate the efficacy and safety of dual therapy comprising sulfonylurea (SU) plus antidiabetic drugs for the treatment of type 2 diabetes mellitus (T2DM).

METHODS

We searched the PubMed, Cochrane library, and Embase databases for randomized clinical trials (≥24 weeks) published up to December 28, 2017. Subsequently, we conducted pairwise and network meta-analyses to calculate the odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals (CIs) of the outcomes.

RESULTS

The final analyses included 24 trials with a total of 10,032 patients. Compared with placebo, all treatment regimens were associated with a significantly higher risk of hypoglycemia, except the combinations of SU plus sodium-glucose co-transporter-2 inhibitor (SGLT-2i) [OR, 1.35 (95% CI: 0.81 to 2.25)] or alpha-glucosidase inhibitor (AGI) [OR, 1.16 (95% CI: 0.55 to 2.44)]. Notably, the combination of SU plus glucagon-like peptide-1 receptor agonist (GLP-1RA) was associated with the most significant increase in the risk of hypoglycemia. Furthermore, all SU-based combination regimens reduced the glycated hemoglobin (HbA1c) and fasting plasma glucose levels (FPG). However, only combinations containing SGLT-2i [MD, -1.00 kg (95% CI: -1.73 to -0.27)] and GLP-1RA [MD, -0.56 kg (95% CI: -1.10 to -0.02)] led to weight loss.

CONCLUSIONS

Our findings highlight the importance of considering the risk of hypoglycemia when selecting antidiabetic drugs to be administered concomitantly with SU. Although all classes of antidiabetic drugs improved glucose control when administered in combination with SU, SGLT-2i might be the best option with respect to factors such as hypoglycemia and body weight.

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.

Current guidelines for the management of non-alcoholic fatty liver disease: A systematic review with comparative analysis

The current epidemic of non-alcoholic fatty liver disease (NAFLD) is reshaping the field of hepatology all around the world. The widespread diffusion of metabolic risk factors such as obesity, type2-diabetes mellitus, and dyslipidemia has led to a worldwide diffusion of NAFLD. In parallel to the increased availability of effective anti-viral agents, NAFLD is rapidly becoming the most common cause of chronic liver disease in Western Countries, and a similar trend is expected in Eastern Countries in the next years. This epidemic and its consequences have prompted experts from all over the word in identifying effective strategies for the diagnosis, management, and treatment of NAFLD. Different scientific societies from Europe, America, and Asia-Pacific regions have proposed guidelines based on the most recent evidence about NAFLD. These guidelines are consistent with the key elements in the management of NAFLD, but still, show significant difference about some critical points. We reviewed the current literature in English language to identify the most recent scientific guidelines about NAFLD with the aim to find and critically analyse the main differences. We distinguished guidelines from 5 different scientific societies whose reputation is worldwide recognised and who are representative of the clinical practice in different geographical regions. Differences were noted in: the definition of NAFLD, the opportunity of NAFLD screening in high-risk patients, the non-invasive test proposed for the diagnosis of NAFLD and the identification of NAFLD patients with advanced fibrosis, in the follow-up protocols and, finally, in the treatment strategy (especially in the proposed pharmacological management). These difference have been discussed in the light of the possible evolution of the scenario of NAFLD in the next years.

Ipragliflozin Add-on Therapy to a GLP-1 Receptor Agonist in Japanese Patients with Type 2 Diabetes (AGATE): A 52-Week Open-Label Study

INTRODUCTION

Few data are available regarding ipragliflozin treatment in combination with glucagon-like peptide-1 (GLP-1) receptor agonists. The aim of this study was to evaluate the efficacy and safety of ipragliflozin in combination with GLP-1 receptor agonists in Japanese patients with inadequately controlled type 2 diabetes mellitus (T2DM).

METHODS

This multicenter study (consisting of three periods: a 4-week washout period, a 6-week observation period, and a 52-week open-label treatment period) included patients aged ≥ 20 years who received a stable dose/regimen of a GLP-1 receptor agonist either solely or in combination therapy with a sulfonylurea for ≥ 6 weeks, with glycosylated hemoglobin (HbA1c) of ≥ 7.5% and a fasting plasma glucose (FPG) of ≥ 126 mg/dL. Ipragliflozin treatment was given at a fixed dose of 50 mg/day for 20 weeks, followed by 50 or 100 mg/day for 32 weeks. Changes from baseline in glycemic control and other parameters were examined; safety was also assessed.

RESULTS

The mean changes in HbA1c and body weight from baseline to end of treatment were - 0.92% and - 2.69 kg, respectively, in all ipragliflozin-treated patients (n = 103). Overall, sustained reductions from baseline were observed for HbA1c, FPG, self-monitored blood glucose, and body weight during the 52-week treatment. The dose increase of ipragliflozin to 100 mg/day resulted in better glycemic control and weight reduction for patients in whom the 50-mg dose was insufficient. Overall, 46.6% (48/103) of patients experienced drug-related adverse events. The most common drug-related treatment-emergent adverse events were pollakiuria (9.7%), hypoglycemia (8.7%), constipation (6.8%), and thirst (5.8%).

CONCLUSION

Combined therapy with ipragliflozin and GLP-1 receptor agonists/sulfonylureas was significantly efficacious in reducing glycemic parameters in patients with T2DM with inadequate glycemic control, and no major safety concerns were identified. The results from this study suggest that ipragliflozin can be recommended as a well-tolerated and effective add-on therapy to a GLP-1 receptor agonist for the treatment of T2DM.

TRIAL REGISTRATION

ClinicalTrials.gov (identifier: NCT02291874).

FUNDING

Astellas Pharma Inc., Tokyo, Japan.

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.

Neoplasms Reported With Liraglutide or Placebo in People With Type 2 Diabetes: Results From the LEADER Randomized Trial

OBJECTIVE

This study explored neoplasm risk with liraglutide versus placebo in the LEADER (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results) cohort.

RESEARCH DESIGN AND METHODS

LEADER (NCT01179048) was an international, phase 3b, randomized, double-blind, controlled trial. Participants aged ≥50 years with type 2 diabetes and high cardiovascular risk were assigned 1:1 to receive liraglutide (≤1.8 mg daily; n = 4,668) or placebo (n = 4,672) in addition to standard care and monitored for 3.5-5 years (median follow-up 3.8 years). The occurrence of neoplasms was a prespecified, exploratory secondary end point. Post hoc analyses of the time to the first confirmed neoplasms were conducted using a Cox regression model.

RESULTS

Neoplasm was confirmed in 10.1% of patients with liraglutide versus 9.0% with placebo (hazard ratio [HR] 1.12 [95% CI 0.99; 1.28]). The HR (95% CI) for liraglutide versus placebo was 1.06 (0.90; 1.25) for malignant neoplasms and 1.16 (0.93; 1.44) for benign neoplasms. Sensitivity analyses excluding neoplasms occurring <1 year or <2 years after randomization and analyses by sex provided similar results. In our main analyses, the 95% CI for the HR included one for all malignant neoplasms evaluated (including pancreatic and thyroid neoplasms) except for prostate neoplasms, which occurred in fewer liraglutide-treated patients.

CONCLUSIONS

LEADER was not primarily designed to assess neoplasm risk. Firm conclusions cannot be made regarding numeric imbalances observed for individual neoplasm types (e.g., pancreatic cancer) that occurred infrequently. LEADER data do, however, exclude a major increase in the risk of total malignant neoplasms with liraglutide versus placebo. Additional studies are needed to assess longer-term exposure.