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

Tolerance develops toward GLP-1 receptor agonists' glucose-lowering effect in mice

Glucagon-like peptide 1 (GLP-1) receptor agonists are popular antidiabetic drugs with potent glucose-lowering effects and low risk of hypoglycemia. Animal experiments and human data indicate that tolerance develops toward at least some of their effects, e.g., gastric motility. Whether tolerance develops toward the glucose-lowering effect of GLP-1 receptor agonists in mice has never been formally tested. The hypothesis of tolerance development in mice will be reported in this study. The direct glucose-lowering effect of the GLP-1 receptor agonists was measured in non-fasted mice and with intraperitoneal glucose tolerance test. Exenatide (10 μg/kg) and liraglutide (600 μg/kg) both substantially lost efficacy during the 18-day treatment as compared to the acute effect. We conclude that our results demonstrate development of tolerance toward GLP-1 receptor agonists' glucose-lowering effect in mice.

Exenatide and Renal Outcomes in Patients with Type 2 Diabetes and Diabetic Kidney Disease

BACKGROUND

Cardiovascular outcomes in clinical trials with type 2 diabetes mellitus (T2DM) patients have shown that glucagon-like peptide-1 receptor agonist can have a beneficial effect on the kidney. This trial aimed to assess the effects of exenatide on renal outcomes in patients with T2DM and diabetic kidney disease (DKD).

METHODS

We performed a randomized parallel study encompassing 4 general hospitals. T2DM patients with an estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2 and macroalbuminuria, defined as 24-h urinary albumin excretion rate (UAER) >0.3 g/24 h were randomized 1:1 to receive exenatide twice daily plus insulin glargine (intervention group) or insulin lispro plus glargine (control group) for 24 weeks. The primary outcome was the UAER percentage change from the baseline after 24 weeks of intervention. The rates of hypoglycemia, adverse events (AEs), and change in eGFR during the follow-up were measured as safety outcomes.

RESULTS

Between March 2016 and April 2019, 92 patients were randomized and took at least 1 dose of the study drug. The mean age of the participants was 56 years. At baseline, the median UAER was 1,512.0 mg/24 h and mean eGFR was 70.4 mL/min/1.73 m2. After 24 weeks of treatment, the UAER percentage change was significantly lower in the intervention group than in the control group (p = 0.0255). Moreover, the body weight declined by 1.3 kg in the intervention group (the difference between the 2 groups was 2.7 kg, p = 0.0001). Compared to the control group, a lower frequency of hypoglycemia and more gastrointestinal AEs were observed in the intervention group.

CONCLUSION

Exenatide plus insulin glargine treatment for 24 weeks resulted in a reduction of albuminuria in T2DM patients with DKD.

Is there a role for glucagon-like peptide-1 receptor agonists in the management of diabetic nephropathy?

Chronic kidney disease constitutes a major microvascular complication of diabetes mellitus. Accumulating data suggest that glucagon-like peptide-1 receptor agonists (GLP-1 RAs) might have a role in the management of diabetic kidney disease (DKD). GLP-1 RAs appear to reduce the incidence of persistent macro-albuminuria in patients with type 2 diabetes mellitus. This beneficial effect appears to be mediated not only by the glucose-lowering action of these agents but also on their blood pressure lowering, anti-inflammatory and antioxidant effects. On the other hand, GLP-1 RAs do not appear to affect the rate of decline of glomerular filtration rate. However, this might be due to the relatively short duration of the trials that evaluated their effects on DKD. Moreover, these trials were not designed nor powered to assess renal outcomes. Given than macrolbuminuria is a strong risk factor for the progression of DKD, it might be expected that GLP-1 RAs will prevent the deterioration in renal function in the long term. Nevertheless, this remains to be shown in appropriately designed randomized controlled trials in patients with DKD.

Efficacy and safety of insulin glargine/lixisenatide fixed-ratio combination (iGlarLixi 1:1) in Japanese patients with type 2 diabetes mellitus inadequately controlled on oral antidiabetic drugs: A randomized, 26-week, open-label, multicentre study: The LixiLan JP-O2 randomized clinical trial

AIMS

To assess efficacy and safety of 26-week treatment with insulin glargine/lixisenatide fixed-ratio combination (iGlarLixi) compared with insulin glargine U100 (iGlar) in Japanese patients with type 2 diabetes mellitus (T2DM) inadequately controlled on oral antidiabetic drugs (OADs).

MATERIALS AND METHODS

This phase 3, multicentre, open-label, 1:1 randomized, parallel-group study compared efficacy of iGlarLixi and iGlar in patients with T2DM, HbA1c of ≥7.5% to ≤9.5% and fasting plasma glucose ≤10.0 mmol/L (180 mg/dL). The primary endpoint was change in HbA1c from baseline to week 26.

RESULTS

Patients were randomized to iGlarLixi (n = 260) or iGlar (n = 261) (mean age 59.7 years, baseline BMI 26.04 kg/m² , and HbA1c 8.04% [64.4 mmol/mol]). HbA1c reduction was significantly greater with iGlarLixi (-1.40% [-15.3 mmol/mol]) than with iGlar (-0.76% [-8.3 mmol/mol]). Significantly more iGlarLixi patients reached HbA1c <7% at week 26 (71.5% vs 38.5%, P < .0001), with significantly lower weight gain (LS mean difference -1.06 kg, P < .0001). Documented symptomatic hypoglycemia (plasma glucose ≤3.9 mmol/L [70 mg/dL]) was recorded in 14.2% of patients with iGlarLixi and 12.3% with iGlar. No severe hypoglycemia was reported in either group. Other than the expected gastrointestinal issues associated with glucagon-like peptide 1 receptor agonists, we found no major difference in the incidence of TEAEs.

CONCLUSIONS

HbA1c reduction was significantly greater with iGlarLixi than with iGlar; significantly more patients achieved HbA1c <7%, with no additional risk of hypoglycemia and without weight gain. iGlarLixi (1:1) provided an effective treatment option for Japanese patients with T2DM inadequately controlled on OADs. Clinical Trial Number: NCT02752828.

Liraglutide and Insulin Have Contrary Effects on Adipogenesis of Human Adipose-Derived Stem Cells via Wnt Pathway

BACKGROUND

Glucagon-like peptide-1 (GLP-1) has been reported to have beneficial impacts on improving human's metabolism and ameliorating insulin resistance. While insulin is another important and conventional drug in diabetes treatment, but it has an adverse effect on weight gain.

PURPOSE

To make sure whether GLP-1 and insulin play different roles in human adipose-derived stem cells (hADSCs).

METHODS

We examined the in vitro roles and molecular mechanisms of liraglutide, a GLP-1 analogue, and human insulin on hADSCs isolated from subcutaneous adipose tissue. Different concentrations (0, 0.1, 1, 10, 100nM) of liraglutide and insulin were added to proliferation and differentiation medium of hADSCs, respectively.

RESULTS

Liraglutide inhibits while insulin promotes the proliferation and differentiation at the concentration of 100nM. Moreover, the levels of GSK-3 increase during differentiation and liraglutide could down-regulate it when compared with insulin. We also find that the activation of phosphorylated GSK-3α and GSK-3β is involved in the differentiation roles. And classical and non-classical Wnt pathways all play roles in the differentiation, which are characterized with the up/down-regulation of the expression of adipogenesis genes such as PPAR-γ and CEBP-α.

CONCLUSION

Liraglutide and insulin have contrary effects on the proliferation and adipogenesis via Wnt pathway in primary cultured ADSCs. Those effects could partly explain the different roles of GLP-1 and insulin on weight gain and insulin resistance.

Signalling, trafficking and glucoregulatory properties of glucagon-like peptide-1 receptor agonists exendin-4 and lixisenatide

BACKGROUND AND PURPOSE

Amino acid substitutions at the N-termini of glucagon-like peptide-1 (GLP-1) receptor agonist peptides result in distinct patterns of intracellular signalling, sub-cellular trafficking and efficacy in vivo. Here, we to determine whether sequence differences at the ligand C-termini of clinically approved GLP-1 receptor agonists exendin-4 and lixisenatide lead to similar phenomena.

EXPERIMENTAL APPROACH

Exendin-4, lixisenatide and N-terminally substituted analogues with biased signalling characteristics were compared across a range of in vitro trafficking and signalling assays in different cell types. Fluorescent ligands and new time-resolved FRET approaches were developed to study agonist behaviours at the cellular and sub-cellular level. Anti-hyperglycaemic and anorectic effects of each parent ligand and their biased derivatives were assessed in mice.

KEY RESULTS

Lixisenatide and exendin-4 showed equal binding affinity, but lixisenatide was fivefold less potent for cAMP signalling. Both peptides induced extensive GLP-1 receptor clustering in the plasma membrane and were rapidly endocytosed, but the GLP-1 receptor recycled more slowly to the cell surface after lixisenatide treatment. These combined deficits resulted in reduced maximal sustained insulin secretion and reduced anti-hyperglycaemic and anorectic effects in mice with lixisenatide. N-terminal substitution of His1 by Phe1 to both ligands had favourable effects on their pharmacology, resulting in improved insulin release and lowering of blood glucose.

CONCLUSION AND IMPLICATIONS

Changes to the C-terminus of exendin-4 affect signalling potency and GLP-1 receptor trafficking via mechanisms unrelated to GLP-1 receptor occupancy. These differences were associated with changes in their ability to control blood glucose and therefore may be therapeutically relevant.

Impact of non-proteinogenic amino acids in the discovery and development of peptide therapeutics

With the development of modern chemistry and biology, non-proteinogenic amino acids (NPAAs) have become a powerful tool for developing peptide-based drug candidates. Drug-like properties of peptidic medicines, due to the smaller size and simpler structure compared to large proteins, can be changed fundamentally by introducing NPAAs in its sequence. While peptides composed of natural amino acids can be used as drug candidates, the majority have shown to be less stable in biological conditions. The impact of NPAA incorporation can be extremely beneficial in improving the stability, potency, permeability, and bioavailability of peptide-based therapies. Conversely, undesired effects such as toxicity or immunogenicity should also be considered. The impact of NPAAs in the development of peptide-based therapeutics is reviewed in this article. Further, numerous examples of peptides containing NPAAs are presented to highlight the ongoing development in peptide-based therapeutics.

The effect of liraglutide on nonalcoholic fatty liver disease in type 2 diabetes mellitus

Aims

The objective is to investigate the effects of liraglutide on nonalcoholic fatty liver disease in type 2 diabetes mellitus.

Materials and methods

Thirty-two patients with T2DM and NAFLD admitted to the Third Affiliated Hospital of Dalian Medical University from December 2014 to December 2016 were selected, including 11 females and 21 males, aged 39.34 ± 8.54 years old. The patients were given liraglutide on the basis of their original hypoglycemic regimen.

Results

After 3 months treatment of liraglutide, FPG was reduced from 8.54 ± 2.21 mmol/L to 6.90 ± 1.73 mmol/L. HbA1c was reduced from 9.72 ± 1.95 to 7.78 ± 1.99. WC was reduced from 103.27 ± 9.92 kg to 93.97 ± 8.35 kg. BMI was reduced from 30.56 ± 4.06 kg/m2 to 28.01 ± 3.12 kg/m2. FLI was reduced from 79.23 ± 16.56 to 58.83 ± 19.75. The differences were statistically significant (p < 0.001). TG was reduced from 2.95 ± 2.13 mmol/L to 2.27 ± 1.31 mmol/L. The difference was significant (p < 0.01). Meanwhile, HOMA-IR was reduced from 1.504 ± 0.002 to 1.503 ± 0.002. GGT was reduced from 62.63 ± 71.61 U/L to 38.13 ± 30.13 U/L. AST was reduced from 27.25 ± 13.74 U/L to 25.44 ± 16.69 U/L. The differences were statistically significant (p < 0.05). After treatment, FCP, TC, HDL-C, LDL-C, ALT, and HOMA-β were also improved compared with before treatment, but the difference was not statistically significant (p > 0.05).

Conclusion

In addition to effectively lowering glucose and improving islet resistance, liraglutide could also improve obesity and adjust blood lipids. However, the improvement of islet function might not be significant after 3 months of treatment. Liraglutide could reduce liver fat accumulation in patients with T2DM and NAFLD.

What may GLP1 receptor agonists contribute to the treatment of patients with non-alcoholic fatty liver disease?

Non-alcoholic fatty liver disease (NAFLD) poses a challenge to health services both in developed and developing countries, with a significant increase in incidence and prevalence that is related to the currently increased prevalence of obesity. Besides an acknowledged higher risk for advanced liver disease (cirrhosis, hepatocellular carcinoma), morbidity and mortality from cardiovascular disease both increase in people with NAFLD. As a matter of fact, NAFLD is a cardiovascular risk factor.

Association between GLP-1 receptor gene polymorphisms with reward learning, anhedonia and depression diagnosis

BACKGROUND

Glucagon-like peptide-1 receptors (GLP-1Rs) are widely expressed in the brain. Evidence suggests that they may play a role in reward responses and neuroprotection. However, the association of GLP-1R with anhedonia and depression diagnosis has not been studied. Here, we examined the association of GLP-1R polymorphisms with objective and subjective measures of anhedonia, as well as depression diagnosis.

METHODS

Objective [response bias assessed by the probabilistic reward task (PRT)] and subjective [Snaith-Hamilton Pleasure Scale (SHAPS)] measures of anhedonia, clinical variables and DNA samples were collected from 100 controls and 164 patients at McLean Hospital. An independent sample genotyped as part of the Psychiatric Genomics Consortium (PGC) was used to study the effect of putative GLP-1R polymorphisms linked to response bias in PRT on depression diagnosis.

RESULTS

The C allele in rs1042044 was significantly associated with increased PRT response bias, when controlling for age, sex, case-control status and PRT discriminability. AA genotype of rs1042044 showed higher anhedonia phenotype based on SHAPS scores. However, analysis of PGC major depressive disorder data showed no association between rs1042044 and depression diagnosis.

CONCLUSION

Findings suggest a possible association of rs1042044 with anhedonia but no association with depression diagnosis.

The treament of hyperglycemia in acute ischemic stroke with incretin-based drugs

Stroke is a major cause of mortality and morbidity worldwide. Considerable experimental and clinical evidence suggests that both diabetes mellitus (DM) and post-stroke hyperglycemia are associated with increased mortality rate and worsened clinical conditions in acute ischemic stroke (AIS) patients. Insulin treatment does not seem to provide convincing benefits for these patients, therefore prompting a change of strategy. The selective agonists of Glucagon-Like Peptide-1 Receptors (GLP-1Ras) and the Inhibitors of Dipeptidyl Peptidase-IV (DPP-IVIs, gliptins) are two newer classes of glucose-lowering drugs used for the treatment of DM. This review examines in detail the rationale for their development and the physicochemical, pharmacokinetic and pharmacodynamic properties and clinical activities. Emphasis will be placed on their neuroprotective effects at cellular and molecular levels in experimental models of acute cerebral ischemia. In perspective, an adequate basis does exist for a novel therapeutic approach to hyperglycemia in AIS patients through the additive treatment with GLP-1Ras plus DPP-IVIs.

New therapeutic targets in chronic kidney disease progression and renal fibrosis

INTRODUCTION

The current therapeutic armamentarium to prevent chronic kidney disease (CKD) progression is limited to the control of blood pressure and in diabetic patients, the strict control of glucose levels. Current research is primarily focused on the reduction of inflammation and fibrosis at different levels.

AREAS COVERED

This article examines the latest progress in this field and places an emphasis on inflammation, oxidative stress, and fibrosis. New therapeutic targets are described and evidence from experimental and clinical studies is summarized. We performed a search in Medline for articles published over the last 10 years.

EXPERT OPINION

The search for therapeutic targets of renal inflammation is hindered by an incomplete understanding of the pathophysiology. The determination of the specific inducers of inflammation in the kidney is an area of heightened potential. Prevention of the progression of renal fibrosis by blocking TGF-β signaling has been unsuccessful, but the investigation of signaling pathways involved in late stages of fibrosis progression could yield improved results. Preventive strategies such as the modification of microbiota-inducers of uremic toxins involved in CKD progression is a promising field because of the interaction between the gut microbiota and the renal system.

CREB-mediated generation and neuronal growth regulates the behavioral improvement of geniposide in diabetes-associated depression mouse model

Metabolic disorder particularly diabetes is one of the leading causes of psychiatric or other neurodegenerative diseases. Previous clinical and pre-clinical studies indicate anti-diabetic drugs such as GLP-1 analogs or GLP-1 receptor (GLP-1R) agonists could perform the neuroprotective effects with multiple molecular mechanisms. As one of natural compound to stimulate GLP-1R, geniposide was reported could improve cognitive behaviors in diabetes associated Alzheimer's disease rat model. Stimulating of GLP-1R could act the crosstalk downstream like neurotrophic factor mediated cAMP-response element binding protein (CREB) would be activated and exert cellular events including promotion of adult neurogenesis, which is one of important treatment targets in antidepressant. Here in this study, we employed HDF in combined with corticosterone (CORT) treatment to create diabetes associated depression model. Geniposide treatment could not only correct the metabolic pattern but could also improve the cognitive dysfunctions and depressive/anxiety symptoms. In consistent with its pro-neurogenic effects, geniposide also enhanced the activity of CREB in hippocampal tissue. Moreover, blocking CREB activity with 666-15 significantly compromised the effects of geniposide in promotion of neurogenesis and behavioral protective effects. In conclusion, this study expands the application of geniposide to treat diabetes associated depression subject and identified the underlying molecular mechanism for such effects.

Cryo-electron microscopy structure of the glucagon receptor with a dual-agonist peptide

Unimolecular dual agonists of the glucagon (GCG) receptor (GCGR) and glucagon-like peptide-1 receptor (GLP-1R) are a new class of drugs that are potentially superior to GLP-1R-specific agonists for the management of metabolic disease. The dual-agonist, peptide 15 (P15), is a glutamic acid 16 analog of GCG with GLP-1 peptide substitutions between amino acids 17 and 24 that has potency equivalent to those of the cognate peptide agonists at the GCGR and GLP-1R. Here, we have used cryo-EM to solve the structure of an active P15-GCGR-G_s complex and compared this structure to our recently published structure of the GCGR-G_s complex bound to GCG. This comparison revealed that P15 has a reduced interaction with the first extracellular loop (ECL1) and the top of transmembrane segment 1 (TM1) such that there is increased mobility of the GCGR extracellular domain and at the C terminus of the peptide compared with the GCG-bound receptor. We also observed a distinct conformation of ECL3 and could infer increased mobility of the far N-terminal His-1 residue in the P15-bound structure. These regions of conformational variance in the two peptide-bound GCGR structures were also regions that were distinct between GCGR structures and previously published peptide-bound structures of the GLP-1R, suggesting that greater conformational dynamics may contribute to the increased efficacy of P15 in activation of the GLP-1R compared with GCG. The variable domains in this receptor have previously been implicated in biased agonism at the GLP-1R and could result in altered signaling of P15 at the GCGR compared with GCG.

Leveraging the Gut to Treat Metabolic Disease

25 years ago, the future of treating obesity and diabetes focused on end organs known to be involved in energy balance and glucose regulation, including the brain, muscle, adipose tissue, and pancreas. Today, the most effective therapies are focused around the gut. This includes surgical options, such as vertical sleeve gastrectomy and Roux-en-Y gastric bypass, that can produce sustained weight loss and diabetes remission but also extends to pharmacological treatments that simulate or amplify various signals that come from the gut. The purpose of this Review is to discuss the wealth of approaches currently under development that seek to further leverage the gut as a source of novel therapeutic opportunities with the hope that we can achieve the effects of surgical interventions with less invasive and more scalable solutions.

Recent advances in understanding the role of glucagon-like peptide 1

The discovery that glucagon-like peptide 1 (GLP-1) mediates a significant proportion of the incretin effect during the postprandial period and the subsequent observation that GLP-1 bioactivity is retained in type 2 diabetes (T2D) led to new therapeutic strategies being developed for T2D treatment based on GLP-1 action. Although owing to its short half-life exogenous GLP-1 has no use therapeutically, GLP-1 mimetics, which have a much longer half-life than native GLP-1, have proven to be effective for T2D treatment since they prolong the incretin effect in patients. These GLP-1 mimetics are a desirable therapeutic option for T2D since they do not provoke hypoglycaemia or weight gain and have simple modes of administration and monitoring. Additionally, over more recent years, GLP-1 action has been found to mediate systemic physiological beneficial effects and this has high clinical relevance due to the post-diagnosis complications of T2D. Indeed, recent studies have found that certain GLP-1 analogue therapies improve the cardiovascular outcomes for people with diabetes. Furthermore, GLP-1-based therapies may enable new therapeutic strategies for diseases that can also arise independently of the clinical manifestation of T2D, such as dementia and Parkinson's disease. GLP-1 functions by binding to its receptor (GLP-1R), which expresses mainly in pancreatic islet beta cells. A better understanding of the mechanisms and signalling pathways by which acute and chronic GLP-1R activation alleviates disease phenotypes and induces desirable physiological responses during healthy conditions will likely lead to the development of new therapeutic GLP-1 mimetic-based therapies, which improve prognosis to a greater extent than current therapies for an array of diseases.

Suitable Use of Injectable Agents to Overcome Hypoglycemia Risk, Barriers, and Clinical Inertia in Community-Dwelling Older Adults with Type 2 Diabetes Mellitus

The management of type 2 diabetes mellitus in older adults requires a comprehensive understanding of the relationship between the disease (medical) and the functional, psychological/cognitive, and social geriatric domains, to individualize both glycemic targets and therapeutic approaches. Prevention of hypoglycemia is a major priority that should be addressed as soon as its presence or risk is detected, adjusting the target and therapeutics accordingly. Nonetheless, treatment intensification should not be neglected when applicable, consistent with recommendations from organizations such as the American Geriatrics Society and the American Diabetes Association, to reduce not only long-term macrovascular and microvascular complications (individualization), but also short-term complications from hyperglycemia (polyuria, volume depletion, urinary incontinence). Such complications can negatively impact the physical and cognitive function of older adults, worsen their quality of life, and additionally affect their families and society. We emphasize individualization, utilizing the multiple classes of antihyperglycemic agents available. Metformin remains as first-line therapy, and additional agents offer advantages and disadvantages that ought to be considered when developing a patient-centric plan of care. For selected cases, injectable therapies such as long-acting basal insulin analogs and glucagon-like peptide-1 receptor agonists can offer advantages to counter hypoglycemia risk, patient-related barriers, and clinical inertia. Furthermore, some injectable agents could potentially simplify regimens while providing safe and effective glycemic control. In this review, we discuss the use of injectable therapies for selected community-dwelling older adults, barriers to transition to injectable therapy, and measures aimed at removing these barriers and assisting physicians and their teams to transition older patients to injectable therapies when appropriate.

The effect of dulaglutide on stroke: an exploratory analysis of the REWIND trial

BACKGROUND

Cardiovascular outcome trials have suggested that glucagon-like peptide 1 (GLP-1) receptor agonists might reduce strokes. We analysed the effect of dulaglutide on stroke within the researching cardiovascular events with a weekly incretin in diabetes (REWIND) trial.

METHODS

REWIND was a multicentre, randomised, double-blind, placebo-controlled trial done at 371 sites in 24 countries. Men and women (aged ≥50 years) with established or newly detected type 2 diabetes whose HbA_1c was 9·5% or less (with no lower limit) on stable doses of up to two oral glucose-lowering drugs with or without basal insulin therapy were eligible if their body-mass index was at least 23 kg/m². Participants were randomly assigned (1:1) to weekly subcutaneous injections of either masked dulaglutide 1·5 mg or the same volume of masked placebo (containing the same excipients but without dulaglutide). Randomisation was done by a computer-generated random code with an interactive web response system with stratification by site. Participants, investigators, the trial leadership, and all other personnel were masked to treatment allocation until the trial was completed and the database was locked. During the treatment period, participants in both groups were instructed to inject study drug on the same day at around the same time, each week. Strokes were categorised as fatal or non-fatal, and as either ischaemic, haemorrhagic, or undetermined. Stroke severity was assessed using the modified Rankin scale. Participants were seen at 2 weeks, 3 months, 6 months, and then every 3 months for drug dispensing and every 6 months for detailed assessments, until 1200 confirmed primary outcomes accrued. The primary endpoint was the first occurrence of any component of the composite outcome, which comprised non-fatal myocardial infarction, non-fatal stroke, or death from cardiovascular or unknown causes. All analyses were done according to an intention-to-treat strategy that included all randomly assigned participants, irrespective of adherence. The trial is registered with ClinicalTrials.gov, number NCT01394952.

FINDINGS

Between Aug 18, 2011, and Aug 14, 2013, we screened 12 133 patients, of whom 9901 with type 2 diabetes and additional cardiovascular risk factors were randomly assigned to either dulaglutide (n=4949) or an equal volume of placebo (n=4952). During a median follow-up of 5·4 years, cerebrovascular and other cardiovascular outcomes were ascertained and adjudicated. 158 (3·2%) of 4949 participants assigned to dulaglutide and 205 (4·1%) of 4952 participants assigned to placebo had a stroke during follow-up (hazard ratio [HR] 0·76, 95% CI 0·62-0·94; p=0·010). Dulaglutide reduced ischaemic stroke (0·75, 0·59-0·94, p=0·012) but had no effect on haemorrhagic stroke (1·05, 0·55-1·99; p=0·89). Dulaglutide also reduced the composite of non-fatal stroke or all-cause death (0·88, 0·79-0·98; p=0·017) and disabling stroke (0·74, 0·56-0·99; p=0·042). The degree of disability after stroke did not differ by treatment group.

INTERPRETATION

Long-term dulaglutide use might reduce clinically relevant ischaemic stroke in people with type 2 diabetes but does not affect stroke severity.

FUNDING

Eli Lilly and Company.

A long-acting, dual-agonist analogue of lamprey GLP-1 shows potent insulinotropic, β-cell protective, and anorexic activities and improves glucose homeostasis in high fat-fed mice

Peptidase-resistant analogues of GLP-1 peptides from sea lamprey and paddlefish ([D-Ala²]palmitoyl-lamprey GLP-1 and [D-Ala²]palmitoyl-paddlefish GLP-1) produced significant (P ≤ 0.05) and concentration-dependent increases in insulin release from BRIN-BD11 clonal β-cells and from isolated mouse islets. Both analogues retained the ability of the native peptides to activate both the GLP-1 receptor (GLP1R) and the glucagon receptor (GCGR). [D-Ala²]palmitoyl-lamprey GLP-1 significantly (P < 0.001) stimulated proliferation of BRIN-BD11 cells and protected against cytokine-induced apoptosis. Administration of the lamprey analogue (25 nmol/kg body weight) to lean mice up to 4 h before a glucose load improved glucose tolerance and increased plasma insulin concentrations. Twice daily administration of the lamprey GLP-1 analogue to high fat-fed mice for 21 days decreased body weight, food intake, and circulating glucose and insulin concentrations. The analogue significantly improved glucose tolerance and insulin sensitivity with beneficial effects on islet β-cell area and insulin secretory responsiveness. Islet gene expression of Glp1r, Gcgr and Gipr significantly increased. The lamprey GLP-1 analogue shows therapeutic promise for treatment of patients with obesity-related Type 2 diabetes.

Glucagon-Like Peptide-1: A Focus on Neurodegenerative Diseases

Diabetes mellitus is one of the major risk factors for cognitive dysfunction. The pathogenesis of brain impairment caused by chronic hyperglycemia is complex and includes mitochondrial dysfunction, neuroinflammation, neurotransmitters’ alteration, and vascular disease, which lead to cognitive impairment, neurodegeneration, loss of synaptic plasticity, brain aging, and dementia. Glucagon-like peptide-1 (GLP-1), a gut released hormone, is attracting attention as a possible link between metabolic and brain impairment. Several studies have shown the influence of GPL-1 on neuronal functions such as thermogenesis, blood pressure control, neurogenesis, neurodegeneration, retinal repair, and energy homeostasis. Moreover, modulation of GLP-1 activity can influence amyloid β peptide aggregation in Alzheimer’s disease (AD) and dopamine (DA) levels in Parkinson’s disease (PD). GLP-1 receptor agonists (GLP-1RAs) showed beneficial actions on brain ischemia in animal models, such as the reduction of cerebral infarct area and the improvement of neurological deficit, acting mainly through inhibition of oxidative stress, inflammation, and apoptosis. They might also exert a beneficial effect on the cognitive impairment induced by diabetes or obesity improving learning and memory by modulating synaptic plasticity. Moreover, GLP-1RAs reduced hippocampal neurodegeneration. Besides this, there are growing evidences on neuroprotective effects of these agonists in animal models of neurodegenerative diseases, regardless of diabetes. In PD animal models, GPL-1RAs were able to protect motor activity and dopaminergic neurons whereas in AD models, they seemed to improve nearly all neuropathological features and cognitive functions. Although further clinical studies of GPL-1RAs in humans are needed, they seem to be a promising therapy for diabetes-associated cognitive decline.

Glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes:real-world evidence from a Mediterranean area

Aims: To assess clinical characteristics and factors associated with glycated hemoglobin (HbA1c) reduction in type 2 diabetes (T2DM) patients initiating glucagon-like peptide-1 receptor agonists (GLP-1RAs). Methods: Retrospective cohort study in patients with T2DM who initiated GLP-1RAs between 2007 and 2014 in primary health care centers in Catalonia (Spain). We evaluated changes in HbA1c and body weight at 6-12 months, and factors independently associated with achieving ≥1% HbA1c target reduction. Results: Overall, 4242 patients (47.9% male; mean BMI 37.5 kg/m²) initiated a GLP-1RA. At 6-12 months, the mean HbA1c level decreased from the baseline 8.8% to 7.7% (-1.0%; SD = 1.6). A 1% reduction in HbA1c was observed in 47.2% of patients. Patients lost a mean of 3.6 kg (SD = 6.2). Sixty percent of patients reduced both HbA1c and body weight, and 17% achieved only one of these targets. Independent determinants of a 1% HbA1c reduction were baseline HbA1c, age, diabetes duration and being on insulin treatment. Reduction in weight or HbA1c and the proportion of patients achieving a HbA1c reduction of ≥1% was significantly larger among subjects prescribed liraglutide than exenatide and lixisenatide. Conclusions: In this real-world, retrospective study, the magnitude of HbA1c and body weight reductions after addition of a GLP-1RA were similar to those observed in randomized controlled trials. Approximately 60% of patients attained reductions in both HbA1c and body weight, and there were significant differences among different drugs from this therapeutic group.

Controlling Obesity and Metabolic Diseases by Hydrodynamic Delivery of a Fusion Gene of Exendin-4 and α1 Antitrypsin

Obesity and associated metabolic comorbidities represent a growing public health problem. In this study, we demonstrate the use of a newly created fusion gene of exendin-4 and α1-antitrypsin to control obesity and obesity-associated metabolic disorders including insulin resistance, fatty liver and hyperglycemia. The fusion gene encodes a protein with exendin-4 peptide placed at the N-terminus of human α-1 antitrypsin, and is named EAT. Hydrodynamic transfer of the EAT gene to mice prevents high-fat diet-induced obesity, insulin resistance and fatty liver development. In diet-induced obese mice, expression of EAT gene induces weight loss, improves glucose homeostasis, and attenuates hepatic steatosis. In ob/ob mice, EAT gene transfer suppresses body weight gain, maintains metabolic homeostasis, and completely blocks fatty liver development. Six-month overexpression of the EAT fusion gene in healthy mice does not lead to any detectable toxicity. Mechanistic study reveals that the resulting metabolic benefits are achieved by a reduced food take and down-regulation of transcription of pivotal genes responsible for lipogenesis and lipid droplet formation in the liver and chronic inflammation in visceral fat. These results validate the feasibility of gene therapy in preventing and restoring metabolic homeostasis under diverse pathologic conditions, and provide evidence in support of a new strategy to control obesity and related metabolic diseases.

A randomized trial comparing the efficacy and safety of treating patients with type 2 diabetes and highly elevated HbA1c levels with basal-bolus insulin or a glucagon-like peptide-1 receptor agonist plus basal insulin: The SIMPLE study

AIM

To compare the efficacy and safety of a glucagon-like peptide-1 receptor agonist (GLP1RA) plus basal insulin versus basal-bolus insulin treatment in patients with very uncontrolled type 2 diabetes.

MATERIALS AND METHODS

The SIMPLE study was a 6-month pragmatic, randomized, open-label trial testing the effectiveness of two approaches to treat patients with type 2 diabetes and HbA1c ≥10%. We randomized patients to detemir plus liraglutide or detemir plus aspart (before each meal). The primary endpoint was change in HbA1c; changes in body weight, insulin dose, hypoglycaemia and diabetes-related quality-of-life were secondary outcomes.

RESULTS

We randomized 120 participants aged 47.4 ± 9.5 years, Hispanic 40%, African American 42%, diabetes duration 10 [25th-75th percentile (6 to 15)] years, body mass index 37.2 ± 10.3 kg/m² . HbA1c decreased more with GLP1RA plus basal insulin [12.2% (95% CI 11.8% to 12.6%) to 8.1% (95% CI 7.4% to 8.7%)] compared with basal-bolus insulin [11.8% (95% CI 11.5% to 12.2%) to 8.8% (95% CI 88.1% to 9.55%)]; estimated treatment difference (ETD) of -1.1% (95% CI -2.0% to -0.1%) (non-inferiority margin 0.4% and P = .0001, superiority P = .026). Compared with basal-bolus insulin, treatment with GLP1RA plus basal insulin led to a body weight ETD of -3.7 kg (95% CI -5.8 to -1.5; P = .001), fewer patients experiencing hypoglycaemia [66.1% vs 35.2% (P = .002)], and greater improvements in general/current health perception, treatment satisfaction, and fear of hypoglycaemia, while taking a lower total daily dose of insulin [estimated treatment ratio 0.68 (95% CI 0.55 to 0.84)].

CONCLUSIONS

In patients with HbA1c ≥10% treatment with GLP1RA plus basal insulin, compared with basal-bolus insulin, resulted in better glycaemic control and body weight, lower insulin dosage and hypoglycaemia, and improved quality of life. This treatment strategy is an effective and safe alternative to a basal-bolus insulin regimen.

Novel advances in monitoring and therapeutic approaches in idiopathic intracranial hypertension

PURPOSE OF REVIEW

The current article appraises the recent developments in idiopathic intracranial hypertension (IIH), with particular attention to novel therapeutic avenues and advanced clinical assessment and monitoring with optical coherence tomography and telemetric intracranial pressure devices.

RECENT FINDINGS

The incidence of IIH is increasing. The first consensus guidelines for IIH have been published detailing investigation and management algorithms for adult IIH. Improved understanding, clinical assessment and monitoring are emerging with the use of optical coherence tomography. Intracranial pressure telemetry is providing unique insights into the physiology of raised intracranial pressure in IIH. There are now an increasing number of ongoing clinical trials evaluating weight loss methods and novel targeted therapies, such as 11ß-HSD1 inhibition and Glucagon-like peptide 1 (GLP-1) receptor agonists.

SUMMARY

Several studies are evaluating new therapies for IIH. Monitoring techniques are advancing, aiding diagnosis and allowing the clinician to accurately evaluate changes in papilloedema and intracranial pressure.

Comparison of desferrioxamine and NODAGA for the gallium-68 labeling of exendin-4

INTRODUCTION

Radiolabeled exendin-4 (Ex4) derivatives are used to target the glucagon-like peptide-1 receptor (GLP-1R) for the clinical diagnosis of insulinomas, a rare type of neuroendocrine tumor. Gallium-68 is an ideal diagnostic nuclide for this application and a study evaluating an exendin-4-NODAGA conjugate is currently underway. However, in complexion with the chelator DFO, its in vivo stability has been a matter of dispute. The aim of this work was to directly compare [⁶⁸Ga]Ga-Ex4NOD with [⁶⁸Ga]Ga-Ex4DFO in vitro and in vivo.

METHODS

In our approach, we directly compared N'-[5-(acetyl-hydroxy-amino)pentyl]-N-[5-[3-(5-aminopentyl-hydroxy-carbamoyl)propanoylamino]pentyl]-N-hydroxy-butane diamide (desferriox-amine B, DFO) and 2-(4,7-bis (carboxymethyl)-1,4,7-triazonan-1-yl) pentanedioic acid (NODAGA) conjugated to exendin-4 in vitro and in vivo. We radiolabeled the peptides with gallium-68, followed by HPLC quality control. In vitro characterization was performed in CHL cells overexpressing the GLP-1R and in vivo studies were conducted with CD1 nu/nu mice carrying tumors derived from these cells.

RESULTS

We found that both peptides could be radiolabeled with a molar activity of about 9.33 MBq/nmol without further purification. They internalized equally well into GLP-1R-expressing cells and their IC₅₀ was similar with 15.6 ± 7.8 nM and 18.4 ± 3.0 nM for [^natGa]Ga-Ex4NOD and [^natGa]Ga-Ex4DFO, respectively. In vivo, [⁶⁸Ga]Ga-Ex4NOD accumulated more in all tissue, while [⁶⁸Ga]Ga-Ex4DFO exhibited a more favorable target-to-kidney ratio.

CONCLUSION AND RELEVANCE

DFO is a suitable chelator for the radiolabeling of exendin-4 derivatives with gallium-68 for in vitro and preclinical in vivo studies. DFO performed better in vivo due to its significantly lower kidney accumulation (p < 0.0001). It was also found to be stable in vivo in mice, contrary to earlier reports. Based on our results, the DFO chelating system in combination with exendin-4 would be an interesting option for clinical imaging of insulinomas.

Comparative effectiveness of exenatide once-weekly versus liraglutide in routine clinical practice: A retrospective multicentre study and meta-analysis of observational studies

In this study, we retrospectively compared the effectiveness of exenatide once-weekly (ExeOW) versus liraglutide in non-insulin treated patients with type 2 diabetes followed under routine care. We also present a meta-analysis of similar observational studies available in the literature. In our multicentre retrospective study, patients initiating ExeOW (n = 204) or liraglutide (n = 410) had similar baseline clinical characteristics. Change in HbA1c at 6 months was superimposable in the two groups (-0.7% ± 1.0%), and changes in body weight were also similar (ExeOW -2.2 ± 3.7 kg; liraglutide -2.5 ± 4.3 kg; p = 0.457). Discontinuation rates were numerically but not significantly lower for ExeOW versus liraglutide. Pooling these data with those of observational studies available in the literature yielded superimposable effects between the two groups for the change in HbA1c and body weight, with a higher risk of discontinuation (mainly based on pharmacy refill rates) for ExeOW. We conclude that, in patients under routine care, initiation of ExeOW provides similar benefits on HbA1c and body weight as initiation of liraglutide. These data help view the results of randomized controlled trials from the perspective of their application in routine clinical practice.

The effects of incretin-based therapies on β-cell function and insulin resistance in type 2 diabetes: A systematic review and network meta-analysis combining 360 trials

AIM

To evaluate the comparative effects of incretin-based therapies, including glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase-4 inhibitors (DPP-4Is), on β-cell function and insulin resistance in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

Medline, Embase, the Cochrane Library and www.clinicaltrials.gov were searched for randomized controlled trials (RCTs) with a duration of at least 4 weeks. Network meta-analysis was performed, followed by subgroup analysis and meta-regression. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the quality of evidence. Outcomes of interest include homeostasis model assessment for β cell function (HOMA-β) and insulin resistance (HOMA-IR), fasting C-peptide and fasting plasma glucose (FPG). Weighted mean difference (WMD) with 95% confidence interval (CI) was calculated as the measure of effect size.

RESULTS

A total of 360 RCTs (74% at least double-blinded) with 157 696 patients were included. Incretin-based therapies were compared with six other classes of glucose-lowering drugs or with placebo. Compared with placebo, a significant increase in HOMA-β and fasting C-peptide was detected for GLP-1RAs (WMD = 20.31 [95% CI, 16.34-24.39] with low quality; WMD = 0.16 ng/mL [95% CI, 0.03-0.29] with low quality) and for DPP-4Is (WMD = 9.90 [95% CI, 8.27-11.61] with moderate quality; WMD = 0.09 ng/mL [95% CI, 0.04-0.14] with moderate quality) separately, while a significant reduction in HOMA-IR and FPG were found in favour of GLP-1RAs (WMD = -0.67 [95% CI, -1.08 to -0.27] with low quality; WMD = -1.04 mmol/L [95% CI, -1.26 to -0.83] with moderate quality) and DPP-4Is (WMD = -0.23 [95% CI, -0.38 to -0.08] with low quality; WMD = -0.77 mmol/L [95% CI, -0.98 to -0.57] with moderate quality), respectively.

CONCLUSIONS

Incretin-based therapies not only show an increase in HOMA-β and fasting C-peptide level, but also achieve a reduction in HOMA-IR and FPG in comparison with placebo. Although GRADE scores indicate low to moderate for most comparisons, incretin-based therapies seem to be an advisable option for long-term treatment to preserve β-cell function.

Diabetes Care for Patients Experiencing Homelessness: Beyond Metformin and Sulfonylureas

On any given night in the United States, an estimated 553,742 people are homeless. Applying a broader definition of homelessness that includes unstably housed people, an estimated 1.5% of Americans experience homelessness in a given year. Rates of diabetes are increasing among individuals experiencing homelessness. The social, psychological, and physical challenges of homelessness not only contribute to the rate of diabetes, but also complicate management. Unstable housing, limited medical resources, food insecurity, and competing priorities are barriers to diabetes care among patients experiencing homelessness. Homeless patients with diabetes more frequently develop specific comorbidities that require special attention, such as cardiovascular disease, substance abuse, depression, and foot wounds. The Affordable Care Act gave states the option to expand Medicaid to those earning up to 138% of the federal poverty level. This addressed a gap in coverage for low-income individuals not eligible for Medicaid or employer-sponsored insurance. With increased insurance coverage, this has increased the variety of medications available to treat hyperglycemia from type 2 diabetes beyond metformin, sulfonylureas, and insulin. Several of the newer classes of medications have advantages for patients experiencing homelessness, but also have special considerations in this vulnerable patient population. This narrative review will provide a review of dipeptidyl peptidase-4 inhibitors, glucagon-like peptide agonists, sodium glucose cotransporter-2 inhibitors, and thiazolidinediones in individuals experiencing homelessness.

The PYY/Y2R-Deficient Mouse Responds Normally to High-Fat Diet and Gastric Bypass Surgery

BACKGROUND/GOALS

The gut hormone peptide YY (PYY) secreted from intestinal L-cells has been implicated in the mechanisms of satiation via Y2-receptor (Y2R) signaling in the brain and periphery and is a major candidate for mediating the beneficial effects of bariatric surgery on appetite and body weight.

METHODS

Here we assessed the role of Y2R signaling in the response to low- and high-fat diets and its role in the effects of Roux-en-Y gastric bypass (RYGB) surgery on body weight, body composition, food intake, energy expenditure and glucose handling, in global Y2R-deficient (Y2RKO) and wildtype (WT) mice made obese on high-fat diet.

RESULTS

Both male and female Y2RKO mice responded normally to low- and high-fat diet in terms of body weight, body composition, fasting levels of glucose and insulin, as well as glucose and insulin tolerance for up to 30 weeks of age. Contrary to expectations, obese Y2RKO mice also responded similarly to RYGB compared to WT mice for up to 20 weeks after surgery, with initial hypophagia, sustained body weight loss, and significant improvements in fasting insulin, glucose tolerance, insulin resistance (HOMA-IR), and liver weight compared to sham-operated mice. Furthermore, non-surgical Y2RKO mice weight-matched to RYGB showed the same improvements in glycemic control as Y2RKO mice with RYGB that were similar to WT mice.

CONCLUSIONS

PYY signaling through Y2R is not required for the normal appetite-suppressing and body weight-lowering effects of RYGB in this global knockout mouse model. Potential compensatory adaptations of PYY signaling through other receptor subtypes or other gut satiety hormones such as glucagon-like peptide-1 (GLP-1) remain to be investigated.

Evaluation of Outcomes After Initiating Triple Antidiabetic Therapy with a GLP-1 RA in an Integrated Health Care System

BACKGROUND

Type 2 diabetes (T2D) is characterized by chronic hyper-glycemia and can lead to life-threatening complications if not treated. A stepwise and patient-centered approach is recommended when managing patients with T2D. Metformin is the preferred first-line agent, while sulfonylureas (SU) are often chosen as second-line agents. If a patient's hemoglobin A1c (A1c) goal is not achieved despite 3 months of treatment with dual therapy, then triple therapy is recommended. However, due to the lack of head-to-head trials for different triple antidiabetic regimens, the recommendations are unclear for selection of an optimal third-line agent.

OBJECTIVE

To evaluate the comparative effectiveness of a glucagon-like peptide-1 receptor agonist (GLP-1 RA) compared with a thiazolidinedione (TZD) or insulin as a third-line add-on therapy in patients who have not achieved A1c goals while receiving metformin and SU dual therapy in the real-world setting within an integrated health care system.

METHODS

This is a retrospective cohort study of adult patients with T2D who were not at goal A1c while on dual therapy with metformin and an SU and initiated triple antidiabetic therapy. The primary outcome was the proportion of patients who achieved goal A1c within 3-7 months after starting triple therapy with a GLP-1 RA compared with a TZD or insulin. Goal A1c was defined as an A1c of < 7% for patients aged less than 65 years and A1c of < 8% for patients aged 65 years or older. Secondary outcomes included mean change in A1c, mean change in weight, and the proportion of patients with an emergent health care encounter due to a hypoglycemic event. Propensity score matching was used to select comparison groups from the insulin and TZD groups with similar baseline characteristics to the GLP-1 RA group in a 4:1 ratio.

RESULTS

274 patients initiated a GLP-1 RA in addition to dual therapy with metformin and an SU. A propensity matched group of 1,096 patients who initiated insulin and 1,096 patients who initiated a TZD were selected as the control groups. Addition of a GLP-1 RA resulted in a significantly lower proportion of patients achieving goal A1c (23.0%) compared with the addition of a TZD (30.8%, P = 0.011). There was no significant difference with the addition of a GLP-1 RA when compared with insulin (24.1%, P = 0.704).

CONCLUSIONS

This study reflects data from real-world practice in a large integrated health care system. Significantly less patients achieved goal A1c with the addition of a GLP-1 RA as a third-line add-on option to dual therapy with metformin and an SU compared with the addition of a TZD. Providers and patients should carefully weigh the risks and benefits of different antidiabetic agents when choosing triple therapy regimens.

DISCLOSURES

No outside funding supported this study. The authors have nothing to disclose. Part of this study was presented as a nonreviewed resident poster at the Academy of Managed Care & Specialty Pharmacy Annual Meeting 2017 in Denver, CO, on March 27-29, 2017.

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.

Glucagon-like peptide-1 receptor agonists for type 2 diabetes: A rational drug development

Today, glucagon-like peptide-1 (GLP-1) receptor agonists are established glucose-lowering drugs used in the management of type 2 diabetes. Their development emerged from the understanding that a combined islet dysfunction comprising of impaired insulin secretion and exaggerated glucagon secretion is the key defect of hyperglycemia. GLP-1 was shown to target these defects, and after the discovery that dipeptidyl peptidase-4 inactivates native GLP-1, several different dipeptidyl peptidase-4-resistant GLP-1 receptor agonists have been developed. They are administered subcutaneously, but show differences in molecular structure, molecular size and pharmacokinetics, the latter allowing twice-daily, once-daily or once-weekly administration. They have been shown to be efficient in reducing both glycated hemoglobin and bodyweight, and to be safe and highly tolerable. Cardiovascular outcomes trials have shown them to be neutral or beneficial. GLP-1 receptor agonists are positioned as add-ons to metformin alone or in combination with oral agents in the clinical paradigm. They are also efficient when combined with insulin, and fixed dose combinations with long-acting insulin have been developed. Recent development includes a very long administration schedule and oral availability. The research from the first demonstration of the antidiabetic action of GLP-1 in the early 1990s to the enormously accumulated data today represents a successful and rational development, which has been characterized by focused perseverance to establish this therapy in the management of type 2 diabetes.

Mechanistic insights from sequential combination therapy with a sodium glucose co-transporter-2 inhibitor and a dipeptidyl peptidase-4 inhibitor: Results from the CANARIS Trial using canagliflozin and teneligliptin

AIM

To elucidate the mechanisms involved in the sequential use of SGLT2 and DPP4 inhibitors (SGLT2i and DPP-4i).

METHODS

Twenty-six type-2 diabetes mellitus patients were recruited into a stepped regimen of 100 mg of canagliflozin daily from day 1, supplemented with 20 mg of teneligliptin daily from day 4. Glucose (Glu), insulin and glucagon were measured at fasting and after ingesting a mixed meal on days 1, 4 and 6.

RESULTS

Canagliflozin decreased fasting plasma glucose to an extent inversely proportional to the change in the glucagon-to-insulin (G/I) ratio. This correlation at fasting was maintained when adding teneligliptin, while the change in the area under the curve of Glu (GluAUC) correlated closely with that in the G/I ratio at fasting and 60 min with canagliflozin. Moreover, these correlations persisted at 60 and 120 min postprandially, but not at fasting on day 6 when teneligliptin was added.

CONCLUSION

The result suggested that the dominant mechanism responsible for the glucose metabolism reflected in the G/I ratio was attributable to SGLT2i and that its active mechanism persisted, despite adding a DPP-4i.

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.

Once-weekly semaglutide for patients with type 2 diabetes: a cost-effectiveness analysis in the Netherlands

OBJECTIVE

Choosing therapies for type 2 diabetes that are both effective and cost-effective is vital as healthcare systems worldwide aim to maximize health of the population. The present analysis assessed the cost-effectiveness of once-weekly semaglutide (a novel glucagon-like peptide-1 (GLP-1) receptor agonist) versus insulin glargine U100 (the most commonly used basal insulin) and versus dulaglutide (an alternative once-weekly GLP-1 receptor agonist), from a societal perspective in the Netherlands.

RESEARCH DESIGN AND METHODS

The IQVIA CORE Diabetes Model was used to project outcomes for once-weekly semaglutide 0.5 mg and 1 mg versus insulin glargine U100, once-weekly semaglutide 0.5 mg versus dulaglutide 0.75 mg, and once-weekly semaglutide 1 mg versus dulaglutide 1.5 mg. Clinical data were taken from the SUSTAIN 4 and SUSTAIN 7 clinical trials. The analysis captured direct and indirect costs, mortality, and the impact of diabetes-related complications on quality of life.

RESULTS

Projections of outcomes suggested that once-weekly semaglutide 0.5 mg was associated with improved quality-adjusted life expectancy by 0.19 quality-adjusted life years (QALYs) versus insulin glargine U100 and 0.07 QALYs versus dulaglutide 0.75 mg. Once-weekly semaglutide 1 mg was associated with mean increases in quality-adjusted life expectancy of 0.27 QALYs versus insulin glargine U100 and 0.13 QALYs versus dulaglutide 1.5 mg. Improvements came at an increased cost versus insulin glargine U100, with incremental cost-effectiveness ratios from a societal perspective of €4988 and €495 per QALY gained for once-weekly semaglutide 0.5 mg and 1 mg, respectively, falling below Netherlands-specific willingness-to-pay thresholds. Improvements versus dulaglutide came at a reduced cost from a societal perspective for both doses of once-weekly semaglutide.

CONCLUSIONS

Once-weekly semaglutide is cost-effective versus insulin glargine U100, and dominant versus dulaglutide 0.75 and 1.5 mg for the treatment of type 2 diabetes, and represents a good use of healthcare resources in the Netherlands.

Repositioning of dipeptidyl peptidase-4 inhibitors and glucagon like peptide-1 agonists as potential neuroprotective agents

Repositioning of dipeptidyl peptidase-4 inhibitors and glucagon like peptide-1 receptor agonists is a breakthrough in the field of neural regeneration research increasing glucagon like peptide-1 bioavailability, hence its neuroprotective activities. In this article, the authors suggest not only crossing blood-brain barrier and neurodegenerative disease as off target for dipeptidyl peptidase-4 inhibitors and glucagon like peptide-1 receptor agonists, but also for ophthalmic preparations for diabetic retinopathy, which may be the latest breakthrough in the field if prepared and used in an appropriate nano-formulation to target the retinal nerves. The relation of neurodegenerative diseases’ different mechanisms to the dipeptidyl peptidase-4 inhibitors and glucagon like peptide-1 receptor agonists should be further examined in preclinical and clinical settings. The repositioning of already marketed antidiabetic drugs for neurodegenerative diseases should save the high cost of the time-consuming normal drug development process. Drug repositioning is a hot topic as an alternative to molecular target based drug discovery or therapeutic switching. It is a relatively inexpensive pathway due to availability of previous pharmacological and safety data. The glucagon like peptide-1 produced in brain has been linked to enhanced learning and memory functions as a physiologic regulator in central nervous system by restoring insulin signaling. Intranasal administration of all marketed gliptins (or glucagon like peptide-1 receptor agonists) may show enhanced blood-brain barrier crossing and increased glucagon like peptide-1 levels in the brain after direct crossing of the drug for the olfactory region, targeting the cerebrospinal fluid. Further blood-brain barrier crossing tests may extend dipeptidyl peptidase-4 inhibitors’ effects beyond the anti-hyperglycemic control to intranasal spray, intranasal powder, or drops targeting the blood-brain barrier and neurodegenerative diseases with the most suitable formula. Moreover, novel nano-formulation is encouraged either to obtain favorable pharmacokinetic parameters or to achieve promising blood-brain barrier penetration directly through the olfactory region. Many surfactants should be investigated either as a solubilizing agent for hydrophobic drugs or as penetration enhancers. Different formulae based on in vitro and in vivo characterizations, working on sister gliptins (or glucagon like peptide-1 receptor agonists), different routes of administration, pharmacokinetic studies, dose response relationship studies, monitoring of plasma/brain concentration ratio after single and multiple dose, and neurodegenerative disease animal models are required to prove the new method of use (utility) for dipeptidyl peptidase-4 inhibitors as potential neuroprotective agents. Furthermore, investigations of glucagon like peptide-1 receptor agonists’ neuroprotective effects on animal models will be considered carefully because they crossed the blood-brain barrier in previous studies, enabling their direct action on the central nervous system. Combination therapy of dipeptidyl peptidase-4 inhibitors or glucagon like peptide-1 receptor agonists with already marketed drugs for neurodegenerative disease should be considered, especially regarding the novel intranasal route of administration.

Liraglutide and cardiovascular outcomes in a real world type 2 diabetes cohort

In the last years, due to new regulatory guidelines requiring a stringent documentation of cardiovascular (CV) safety of novel drugs for type 2 diabetes, cardiovascular outcomes safety trials (CVOTs) are requested. CVOTs increase the knowledge about the safety profile of the new drugs, but they have intrinsic limits that make difficult their transferability to clinical practice. For this reason, real world evidence is considered an important complement to experimental data. Among the glucagon-like peptide-1 receptor agonists, liraglutide in the LEADER CVOT demonstrated superiority in reducing the risk of major CV events (MACEs) vs. placebo. We conducted an observational, retrospective, longitudinal study based on 307 patients with T2DM treated with liraglutide under routine clinical practice conditions. Real world impact of liraglutide on metabolic control, CV risk factors, hypoglycemia and CV events was assessed. Improvements during 36 months were found in HbA_1c (-1.0%; p < 0.0001), fasting blood glucose (-17.6 mg/dL; p < 0.0001), body weight (-3.2 kg; p < 0.0001), waist circumference (-1.45 cm; p = 0.004), systolic blood pressure (-10.41 mmHg; p < 0.0001), diastolic blood pressure (-3.69 mmHg; p < 0.0001), total cholesterol (-7.96 mg/dL; p =0.008) and triglycerides (-20.60 mg/dl; p = 0.01). No severe hypoglycemia occurred. Incidence of MACEs in this cohort was lower than in the LEADER study (2.59 vs. 3.4 events per 100 person-years), confirming CV safety of liraglutide even in the real world. On the other hand, a higher incidence of CV event in patients with established CV disease was documented (8.1 events per 100 person-years), in spite of the use of liraglutide. In conclusion, 36-month durability and CV safety of liraglutide were documented in a real world cohort of T2DM patients, with sustained benefits on a large array of CV risk factors.

A paradigm shift for the prevention and treatment of individual and global obesity

The prevalence of obesity and overweight has plateaued in developed countries, although at high levels, but in most parts of the world, it continues to increase. Current recommendations for preventing and treating obesity are based mainly on the notion that overeating results from hedonic eating as a result of unlimited access to palatable foods, particularly those high in sugar and fat, and that hedonic centers are able to "override" the body's homeostatic mechanisms. This article proposes that the homeostatic mechanisms affecting appetite and satiety are more important in chronic overeating, and that sufficient evidence exists for adopting a new paradigm for controlling individual and global obesity based on controlling energy homeostasis via the enteroendocrine and gut microbiota systems. Many obese children and adolescents have chronic hunger, supporting the notion that they have a homeostatic rather than hedonic abnormality. The effectiveness of weight loss drugs and bariatric surgery suggests that the brain centers controlling energy homeostasis are able to override centers controlling hedonic drives. Energy homeostasis can also be influenced by nutrition, in particular, by avoiding sweetened drinks and consuming whole grains, vegetables, fruits and other foods that are high in dietary fiber, and thereby influence appetite and satiety. New recommendations are outlined for preventing and treating individual and global obesity based on a paradigm that targets appetite and satiety.