Exenatide or glimepiride added to metformin on metabolic control and on insulin resistance in type 2 diabetic patients

Benefits and risks of drug combination therapy for diabetes mellitus and its complications: a comprehensive review

Diabetes is a chronic metabolic disease, and its therapeutic goals focus on the effective management of blood glucose and various complications. Drug combination therapy has emerged as a comprehensive treatment approach for diabetes. An increasing number of studies have shown that, compared with monotherapy, combination therapy can bring significant clinical benefits while controlling blood glucose, weight, and blood pressure, as well as mitigating damage from certain complications and delaying their progression in diabetes, including both type 1 diabetes (T1D), type 2 diabetes (T2D) and related complications. This evidence provides strong support for the recommendation of combination therapy for diabetes and highlights the importance of combined treatment. In this review, we first provided a brief overview of the phenotype and pathogenesis of diabetes and discussed several conventional anti-diabetic medications currently used for the treatment of diabetes. We then reviewed several clinical trials and pre-clinical animal experiments on T1D, T2D, and their common complications to evaluate the efficacy and safety of different classes of drug combinations. In general, combination therapy plays a pivotal role in the management of diabetes. Integrating the effectiveness of multiple drugs enables more comprehensive and effective control of blood glucose without increasing the risk of hypoglycemia or other serious adverse events. However, specific treatment regimens should be tailored to individual patients and implemented under the guidance of healthcare professionals.

Effects of GLP-1 Agonists on mortality and arrhythmias in patients with Type II diabetes

Background

Glucagon-like Peptide-1 Receptor Agonists (GLP-1 RA) are frequently used for the management of diabetes. The impact of GLP-1 RA on cardiovascular outcomes is unclear. We aim to assess the effect of GLP-1 RA on mortality, atrial and ventricular arrhythmias, and sudden cardiac death in patients with type II diabetes.

Methods

We searched databases including Ovid MEDLINE, EMBASE, Scopus, Web of Science, Google Scholar and CINAHL, from inception to May 2022, for randomized controlled trials reporting the relationship between GLP-1 RA (including albiglutide, dulaglutide, exenatide, liraglutide, lixisenatide, and semaglutide) and mortality, atrial arrhythmias, and the combined incidence of ventricular arrhythmias and sudden cardiac death. The search was not restricted to time or publication status.

Results

A total of 464 studies resulted from literature search, of which 44 studies, including 78,702 patients (41,800 GLP-1 agonists vs 36,902 control), were included. Follow up ranged from 52 to 208 weeks. GLP-1 RA were associated with lower risk of all-cause mortality (odds ratio 0.891, 95% confidence interval 0.837-0.949; P < 0.01) and reduced cardiovascular mortality (odds ratio 0.88, 95% confidence interval 0.881-0.954; P < 0.01). GLP-1 RA were not associated with increased risk of atrial (odds ratio 0.963, 95% confidence interval 0.869-1.066; P 0.46) or ventricular arrhythmias and sudden cardiac death (odds ratio 0.895, 95% confidence interval 0.706-1.135; P 0.36).

Conclusion

GLP-1 RA are associated with decreased all-cause and cardiovascular mortality, and no increased risk of atrial and ventricular arrhythmias and sudden cardiac death.

Pancreatitis and pancreatic cancer in patients with type 2 diabetes treated with glucagon-like peptide-1 receptor agonists: an updated meta-analysis of randomized controlled trials

INTRODUCTION

An association between glucagon-like peptide-1 receptor agonists (GLP1-RA) and risk of pancreatitis and pancreatic cancer has been suggested. Since its first description, several new trials (including three cardiovascular outcome trials) have been published, substantially increasing the available data set. This suggests the need for an update of the previous meta-analysis.

EVIDENCE ACQUISITION

A Medline search for GLP-1 receptor agonists (exenatide, liraglutide, lixisenatide, albiglutide, dulaglutide, or semaglutide) was performed, collecting all randomized clinical trials, with duration ≥52 weeks, enrolling patients with type 2 diabetes, and comparing a GLP-1 receptor agonist with placebo or any other non-GLP-1 receptor agonist drug. The endpoints were pancreatitis, pancreatic cancer reported as serious adverse events. Mantel-Haenszel Odds Ratio (MH-OR) with 95% confidence interval (95% CI) was calculated for all outcomes defined above, on an intention-to-treat basis.

EVIDENCE SYNTHESIS

A total of 43 trials fulfilling inclusion criteria (all reporting data on pancreatitis and pancreatic cancer) was identified. GLP-1 RA showed no association with pancreatitis (MH-OR 1.24 [0.94, 1.64]; P=0.13) and pancreatic cancer (MH-OR 1.28 [0.87, 1.89]; P=0.20).

CONCLUSIONS

No clear evidence of risk for pancreatitis was observed, whereas data on pancreatic cancer are too scarce to draw any conclusion.

Resistin levels decrease as insulin resistance increases in a Mexican-American cohort

AIMS

Links between resistin, insulin resistance (IR), and resistin-stimulated cytokine signaling remain unknown in Mexican-Americans. A Mexican-American cohort was examined to determine (1) relationships between circulating resistin and IR, (2) resistin's associations with cytokines and demographic and anthropometric variables, and (3) similar measurements with other adipokines.

METHODS

For cross sectional analyses, 953 adults (367 males and 586 females) in the Cameron County Hispanic Cohort (CCHC) were stratified into three groups: normal glucose tolerance, prediabetes, and diabetes mellitus. Differences in resistin and other adipokine levels were examined using linear regression via unadjusted model (Model 1), model adjusted for cytokines (Model 2), and model further adjusted for demographic and anthropometric variables (Model 3).

RESULTS

HOMA-IR increased with worsening glucose tolerance (p < 0.0001). In all models, resistin significantly decreased as glucose tolerance deteriorated. Model 3 resistin was positively associated with IL-1β (p = 0.0252) and IL-8 (p < 0.0001), inversely associated with TNF-α (p = 0.0352), but nonsignificantly associated with IL-6 (p = 0.8671). Model 3 leptin was significantly lower in diabetes mellitus compared to other groups (p < 0.005) and positively associated with female sex (p < 0.0001), age (p = 0.024), and BMI (p < 0.0001), without significant cytokine associations. Adiponectin displayed no significant associations with glucose tolerance, but was significantly associated with sex, BMI, and lipids (Model 3).

CONCLUSIONS

Resistin unexpectedly decreased as IR increased while supporting evidence of a resistin-stimulated cytokine pathway in this Mexican-American cohort. Leptin fell with elevated IR after adjusting for cytokines, demographic and anthropometric variables. Adiponectin nonsignificantly decreased as IR increased while showing significant associations with sex, BMI, and lipids.

Changing the approach to type 2 diabetes treatment: A comparison of glucagon-like peptide-1 receptor agonists and sulphonylureas across the continuum of care

Despite the importance of individualised strategies for patients with type 2 diabetes mellitus (T2DM) and the availability of alternative treatments, including glucagon-like peptide-1 receptor agonists (GLP-1 RAs), sulphonylureas are still widely used in practice. Clinical evidence shows that GLP-1 RAs may provide better and more durable glycaemic control than sulphonylureas, with lower risk of hypoglycaemia. Other reported benefits of GLP-1 RAs include weight loss rather than weight gain (as observed with sulphonylureas), blood pressure reduction and improvement in lipid profiles. In general, the main adverse events with GLP-1 RAs are gastrointestinal in nature. The respective modes of action of GLP-1 RAs and sulphonylureas contribute to differences in the durability of glycaemic control (related to effects on beta-cells) and effects on body weight. Moreover, the glucose-dependent mode of action of GLP-1 RAs, which favours a low incidence of hypoglycaemia, contrasts with the glucose-independent mode of action of sulphonylureas. Evidence from cardiovascular outcomes trials indicates a consistent finding of cardiovascular safety across the GLP-1 RAs and suggests a class benefit for the long-acting GLP-1 RAs in reducing three-point major adverse cardiovascular events, cardiovascular mortality and all-cause mortality. In contrast, potential concerns relating to an increased incidence of adverse cardiovascular events with sulphonylureas have yet to be fully resolved. Recent updates to management guidelines recommend that treatment selection for patients with T2DM should consider clinical trial evidence of cardiovascular safety. Available evidence suggests that this selection should give preference to GLP-1 RAs over sulphonylureas, especially for patients at high cardiovascular risk.

High protein diet leads to prediabetes remission and positive changes in incretins and cardiovascular risk factors

BACKGROUND AND AIMS

High Protein diets may be associated with endocrine responses that favor improved metabolic outcomes. We studied the response to High Protein (HP) versus High Carbohydrate (HC) Diets in terms of incretin hormones GLP-1 and GIP, the hunger hormone ghrelin and BNP, which is associated with cardiac function. We hypothesized that HP diets induce more pronounced release of glucose lowering hormones, suppress hunger and improve cardiac function.

METHODS AND RESULTS

24 obese women and men with prediabetes were recruited and randomized to either a High Protein (HP) (n = 12) or High Carbohydrate (HC) (n = 12) diet for 6 months with all food provided. OGTT and MTT were performed and GLP-1, GIP, Ghrelin, BNP, insulin and glucose were measured at baseline and 6 months on the respective diets. Our studies showed that subjects on the HP diet had 100% remission of prediabetes compared to only 33% on the HC diet with similar weight loss. HP diet subjects had a greater increase in (1) OGTT GLP-1 AUC(p = 0.001) and MTT GLP-1 AUC(p = 0.001), (2) OGTT GIP AUC(p = 0.005) and MTT GIP AUC(p = 0.005), and a greater decrease in OGTT ghrelin AUC(p = 0.005) and MTT ghrelin AUC(p = 0.001) and BNP(p = 0.001) compared to the HC diet at 6 months.

CONCLUSIONS

This study demonstrates that the HP diet increases GLP-1 and GIP which may be responsible in part for improved insulin sensitivity and β cell function compared to the HC diet. HP ghrelin results demonstrate the HP diet can reduce hunger more effectively than the HC diet. BNP and other CVRF, metabolic parameters and oxidative stress are significantly improved compared to the HC diet. CLINICALTRIALS.

GOV IDENTIFIER

NCT01642849.

Exenatide Twice Daily Plus Glargine Versus Aspart 70/30 Twice Daily in Patients With Type 2 Diabetes With Inadequate Glycemic Control on Premixed Human Insulin and Metformin

OBJECTIVE

Many patients with type 2 diabetes treated with premixed insulin gradually have inadequate glycemic control and switch to a basal-bolus regimen, which raises some concerns for weight gain and increased hypoglycemic risk. Switching to combination use of glp-1 agonist and basal insulin may be an alternative option.

METHODS

After a 12-week premixed human insulin 70/30 dosage optimization period, 200 patients with HbA1c of 7.0% to 10.0% were randomized into 24-week treatment groups with exenatide twice a day plus glargine or with aspart 70/30 twice a day.

RESULTS

After 24 weeks, the patients receiving exenatide plus glargine (n = 90) had improved HbA1c control compared with those receiving aspart 70/30 (n = 90) (least squares mean change: ‒0.59 vs ‒0.13%; difference [95% CI]: ‒0.45 [‒0.74 to ‒0.17]) in the full analysis set population. Weight decreased 3.5 kg with exenatide and decreased 0.4 kg with aspart 70/30 (P < .001). The insulin dose was reduced 10.7 units/day (95% CI, ‒12.2 to ‒9.2 units; P < .001) with exenatide, and increased 9.7 units/day (95% CI, 8.2 to 11.2 units; P < .001) with aspart 70/30. The most common adverse events were gastrointestinal adverse effects in the exenatide group (nausea [21%], vomiting [16%], diarrhea [13%]). The incidence of hypoglycemia was similar in 2 groups (27% for exenatide and 38% for aspart 70/30; P = .1).

CONCLUSION

In premixed human insulin‒treated patients with type 2 diabetes with inadequate glycemic control, switching to exenatide twice a day plus glargine was superior to aspart 70/30 twice a day for glycemic and weight control.

The Position of Gliclazide in the Evolving Landscapes and Disease Continuum of T2DM: A Collaborative Delphi Survey-Based Consensus from India

INTRODUCTION

This Delphi study aims to provide evidence-based expert opinion on the usage and current position of gliclazide in type 2 diabetes mellitus (T2DM) management in India.

METHODS

The single interaction modified Delphi-based methodology was used to collect opinions on gliclazide usage and its position in diabetes management from 338 endocrinologists/diabetologists who have had clinical experience with gliclazide. Participants, using a 9-point scale, were asked to rate eight statements comprising a total of 52 items on the related topics.

RESULTS

The Delphi consensus suggests that in drug-naïve patients with T2DM, intolerant to metformin or in whom metformin is contraindicated, dual therapy of gliclazide/gliclazide-modified release (MR) should be considered along with a dipeptidyl peptidase 4 (DPP4) inhibitor if glycated hemoglobin A1c level is greater than 7.5% and with insulin if the A1c level is greater than 9%. If the patients are inadequately controlled with metformin (A1c greater than 6.5% after 3 months of therapy), gliclazide/gliclazide-MR shall be added on to the treatment regimen to achieve greater and sustained reductions in A1c levels. However, it was not preferred over other antidiabetic classes in such clinical settings except alpha-glucosidase inhibitors (AGI). Early addition of gliclazide/gliclazide-MR shall be preferred over the up-titration of metformin beyond half-maximal dose for effective management of T2DM. Gliclazide/gliclazide-MR can be used safely in patients with diabetes and cardiovascular and chronic kidney disease. It can be used in older patients with T2DM as it does not have active metabolites and has a low risk of hypoglycemia.

CONCLUSION

The expert panel proposed consideration of monotherapy or dual therapy of gliclazide as an ideal choice in patients with T2DM because of its efficacy, long-term glycemic control, favorable renal outcomes, cardiovascular safety, and an optimal safety profile.

Major cardiovascular events, heart failure, and atrial fibrillation in patients treated with glucagon-like peptide-1 receptor agonists: An updated meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Glucagon-like Peptide 1 Receptor Agonists (GLP1-RA) has been associated with a reduction of major cardiovascular events (MACE) and mortality on the basis of the results of cardiovascular outcome trials (CVOT). Several meta-analyses on this issue have been recently published; however, they were all restricted to CVOT, with the exclusion of all studies designed for other endpoints; moreover, other cardiovascular endpoints, such as atrial fibrillation and heart failure have not been fully explored.

METHODS AND RESULTS

A Medline search for GLP-1 receptor agonists (exenatide, liraglutide, lixisenatide, albiglutide, dulaglutide, or semaglutide) was performed, collecting all randomized clinical trials with a duration ≥52 weeks, enrolling patients with type 2 diabetes, and comparing a GLP-1 receptor agonist with placebo or any other non-GLP-1 receptor agonist drug. We included 43 trials, enrolling 63,134 patients. A significant reduction of MACE (MH-OR 0.87 [0.83, 0.92]), all-cause mortality (MH-OR 0.89 [0.83, 0.96]), and a nonstatistical trend toward reduction of heart failure (MH-OR 0.93 [0.85, 1.01]) was observed - GLP1-RA did not increase the risk of atrial fibrillation (MH-OR 0.94 [0.84, 1.04]).

CONCLUSION

The present meta-analysis confirms the favorable effects of glucagon-like peptide-1 receptor agonists on major cardiovascular events, cardiovascular and all-cause mortality, stroke, and possibly myocardial infarction. Conversely, the effects on heart failure remain uncertain. Available data on atrial fibrillation seems to exclude any major safety issues in this respect.

REGISTRATION NUMBER (PROSPERO)

CRD42018115577.

Effects of Nigella Sativa on Type-2 Diabetes Mellitus: A Systematic Review

Diabetes mellitus is one of the most prevalent metabolic disorders that affect people of all genders, ages, and races. Medicinal herbs have gained wide attention from researchers and have been considered to be a beneficial adjuvant agent to oral antidiabetic drugs because of their integrated effects. Concerning the various beneficial effects of Nigella sativa, this systematic review aims to provide comprehensive information on the effects of Nigella sativa on glucose and insulin profile status in humans. A computerized database search performed through Scopus and Medline via Ebscohost with the following set of keywords: Nigella Sativa OR black seed oil OR thymoquinone OR black cumin AND diabetes mellitus OR hyperglycemia OR blood glucose OR hemoglobin A1C had returned 875 relevant articles. A total of seven articles were retrieved for further assessment and underwent data extraction to be included in this review. Nigella sativa was shown to significantly improve laboratory parameters of hyperglycemia and diabetes control after treatment with a significant fall in fasting blood glucose, blood glucose level 2 h postprandial, glycated hemoglobin, and insulin resistance, and a rise in serum insulin. In conclusion, these findings suggested that Nigella sativa could be used as an adjuvant for oral antidiabetic drugs in diabetes control.

Orally Administered Semaglutide Versus GLP-1 RAs in Patients with Type 2 Diabetes Previously Receiving 1-2 Oral Antidiabetics: Systematic Review and Network Meta-Analysis

INTRODUCTION

Orally administered semaglutide is the first glucagon-like peptide 1 receptor agonist (GLP-1 RA) for oral administration. As head-to-head trials assessing orally administered semaglutide as an add-on to 1-2 oral antidiabetic drugs (OADs) vs other GLP-1 RAs are limited, a network meta-analysis (NMA) was performed to assess the relative efficacy and safety of orally administered semaglutide 14 mg once-daily (QD) vs injectable GLP-1 RAs in patients with type 2 diabetes inadequately controlled on 1-2 OADs.

METHODS

A systematic literature review was conducted to identify randomised controlled trials of GLP-1 RAs in patients inadequately controlled on 1-2 OADs. Data at 26 ± 4 weeks were extracted for efficacy and safety outcomes feasible for the NMA: change from baseline in glycated haemoglobin (HbA_1c), weight, HbA_1c target levels (< 7.0% and ≤ 6.5%), blood pressure, and any gastrointestinal adverse events specified in system organ class. Data were synthesised using NMA and a Bayesian framework.

RESULTS

In total, 27 studies were included in the analyses. Orally administered semaglutide 14 mg QD was associated with significantly greater reductions in HbA_1c vs most comparators, and numerically greater reductions vs semaglutide 0.5 mg once-weekly (QW), dulaglutide 1.5 mg QW and liraglutide 1.8 mg QD. HbA_1c reductions with semaglutide 1 mg QW were numerically greater than those with orally administered semaglutide 14 mg QD. Reductions in body weight for orally administered semaglutide 14 mg QD were significantly greater than all comparators except semaglutide QW (both doses). Orally administered semaglutide QD 14 mg was associated with statistically similar odds of experiencing gastrointestinal adverse events vs injectable GLP-1 RAs.

CONCLUSION

Orally administered semaglutide 14 mg QD as an add-on to 1-2 OADs is one of the most efficacious GLP-1 RAs for reducing HbA_1c and body weight at 26 ± 4 weeks. Orally administered semaglutide 14 mg QD is well tolerated, with a safety profile in line with the GLP-1 RA class.

FUNDING

Novo Nordisk.

GLP-1 Receptor Agonists for Type 2 Diabetes and Their Role in Primary Care: An Australian Perspective

The ever-increasing number of drugs available to treat type 2 diabetes and the complexity of patients with this condition present a constant challenge when it comes to identifying the most appropriate treatment approach. The more recent glucagon-like peptide-1 receptor agonists (GLP-1RAs) are non-insulin injectable options for the management of type 2 diabetes. Effective at improving glycaemic control with a low intrinsic risk of hypoglycaemia and the potential for weight reduction, this agent class is an important addition to the prescribing armamentarium. However, understanding their place in therapy may prove confusing for many primary care practitioners, especially given the common belief that 'injectables' are a last-resort treatment option, which puts them at risk of being niched alongside insulin. This review summarises the clinical evidence for GLP-1RAs and how they compare to other glucose-lowering agents in managing type 2 diabetes. It also provides practical and case-driven opinions and recommendations on the optimal use of GLP-1RAs by discussing important patient factors and clinical considerations that will help to identify those who are most likely to benefit from this class of agents.Funding: Eli Lilly Australia.

Metformin and second- or third-generation sulphonylurea combination therapy for adults with type 2 diabetes mellitus

BACKGROUND

The number of people with type 2 diabetes mellitus (T2DM) is increasing worldwide. The combination of metformin and sulphonylurea (M+S) is a widely used treatment. Whether M+S shows better or worse effects in comparison with other antidiabetic medications for people with T2DM is still controversial.

OBJECTIVES

To assess the effects of metformin and sulphonylurea (second- or third-generation) combination therapy for adults with type 2 diabetes mellitus.

SEARCH METHODS

We updated the search of a recent systematic review from the Agency for Healthcare Research and Quality (AHRQ). The updated search included CENTRAL, MEDLINE, Embase, ClinicalTrials.gov and WHO ICTRP. The date of the last search was March 2018. We searched manufacturers' websites and reference lists of included trials, systematic reviews, meta-analyses and health technology assessment reports. We asked investigators of the included trials for information about additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) randomising participants 18 years old or more with T2DM to M+S compared with metformin plus another glucose-lowering intervention or metformin monotherapy with a treatment duration of 52 weeks or more.

DATA COLLECTION AND ANALYSIS

Two review authors read all abstracts and full-text articles and records, assessed risk of bias and extracted outcome data independently. We used a random-effects model to perform meta-analysis, and calculated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the certainty of the evidence using the GRADE instrument.

MAIN RESULTS

We included 32 RCTs randomising 28,746 people. Treatment duration ranged between one to four years. We judged none of these trials as low risk of bias for all 'Risk of bias' domains. Most important events per person were all-cause and cardiovascular mortality, serious adverse events (SAE), non-fatal stroke (NFS), non-fatal myocardial infarction (MI) and microvascular complications. Most important comparisons were as follows:Five trials compared M+S (N = 1194) with metformin plus a glucagon-like peptide 1 analogue (N = 1675): all-cause mortality was 11/1057 (1%) versus 11/1537 (0.7%), risk ratio (RR) 1.15 (95% confidence interval (CI) 0.49 to 2.67); 3 trials; 2594 participants; low-certainty evidence; cardiovascular mortality 1/307 (0.3%) versus 1/302 (0.3%), low-certainty evidence; serious adverse events (SAE) 128/1057 (12.1%) versus 194/1537 (12.6%), RR 0.90 (95% CI 0.73 to 1.11); 3 trials; 2594 participants; very low-certainty evidence; non-fatal myocardial infarction (MI) 2/549 (0.4%) versus 6/1026 (0.6%), RR 0.57 (95% CI 0.12 to 2.82); 2 trials; 1575 participants; very low-certainty evidence.Nine trials compared M+S (N = 5414) with metformin plus a dipeptidyl-peptidase 4 inhibitor (N = 6346): all-cause mortality was 33/5387 (0.6%) versus 26/6307 (0.4%), RR 1.32 (95% CI 0.76 to 2.28); 9 trials; 11,694 participants; low-certainty evidence; cardiovascular mortality 11/2989 (0.4%) versus 9/3885 (0.2%), RR 1.54 (95% CI 0.63 to 3.79); 6 trials; 6874 participants; low-certainty evidence; SAE 735/5387 (13.6%) versus 779/6307 (12.4%), RR 1.07 (95% CI 0.97 to 1.18); 9 trials; 11,694 participants; very low-certainty evidence; NFS 14/2098 (0.7%) versus 8/2995 (0.3%), RR 2.21 (95% CI 0.74 to 6.58); 4 trials; 5093 participants; very low-certainty evidence; non-fatal MI 15/2989 (0.5%) versus 13/3885 (0.3%), RR 1.45 (95% CI 0.69 to 3.07); 6 trials; 6874 participants; very low-certainty evidence; one trial in 64 participants reported no microvascular complications were observed (very low-certainty evidence).Eleven trials compared M+S (N = 3626) with metformin plus a thiazolidinedione (N = 3685): all-cause mortality was 123/3300 (3.7%) versus 114/3354 (3.4%), RR 1.09 (95% CI 0.85 to 1.40); 6 trials; 6654 participants; low-certainty evidence; cardiovascular mortality 37/2946 (1.3%) versus 41/2994 (1.4%), RR 0.78 (95% CI 0.36 to 1.67); 4 trials; 5940 participants; low-certainty evidence; SAE 666/3300 (20.2%) versus 671/3354 (20%), RR 1.01 (95% CI 0.93 to 1.11); 6 trials; 6654 participants; very low-certainty evidence; NFS 20/1540 (1.3%) versus 16/1583 (1%), RR 1.29 (95% CI 0.67 to 2.47); P = 0.45; 2 trials; 3123 participants; very low-certainty evidence; non-fatal MI 25/1841 (1.4%) versus 21/1877 (1.1%), RR 1.21 (95% CI 0.68 to 2.14); P = 0.51; 3 trials; 3718 participants; very low-certainty evidence; three trials (3123 participants) reported no microvascular complications (very low-certainty evidence).Three trials compared M+S (N = 462) with metformin plus a glinide (N = 476): one person died in each intervention group (3 trials; 874 participants; low-certainty evidence); no cardiovascular mortality (2 trials; 446 participants; low-certainty evidence); SAE 34/424 (8%) versus 27/450 (6%), RR 1.68 (95% CI 0.54 to 5.21); P = 0.37; 3 trials; 874 participants; low-certainty evidence; no NFS (1 trial; 233 participants; very low-certainty evidence); non-fatal MI 2/215 (0.9%) participants in the M+S group; 2 trials; 446 participants; low-certainty evidence; no microvascular complications (1 trial; 233 participants; low-certainty evidence).Four trials compared M+S (N = 2109) with metformin plus a sodium-glucose co-transporter 2 inhibitor (N = 3032): all-cause mortality was 13/2107 (0.6%) versus 19/3027 (0.6%), RR 0.96 (95% CI 0.44 to 2.09); 4 trials; 5134 participants; very low-certainty evidence; cardiovascular mortality 4/1327 (0.3%) versus 6/2262 (0.3%), RR 1.22 (95% CI 0.33 to 4.41); 3 trials; 3589 participants; very low-certainty evidence; SAE 315/2107 (15.5%) versus 375/3027 (12.4%), RR 1.02 (95% CI 0.76 to 1.37); 4 trials; 5134 participants; very low-certainty evidence; NFS 3/919 (0.3%) versus 7/1856 (0.4%), RR 0.87 (95% CI 0.22 to 3.34); 2 trials; 2775 participants; very low-certainty evidence; non-fatal MI 7/890 (0.8%) versus 8/1374 (0.6%), RR 1.43 (95% CI 0.49 to 4.18; 2 trials); 2264 participants; very low-certainty evidence; amputation of lower extremity 1/437 (0.2%) versus 1/888 (0.1%); very low-certainty evidence.Trials reported more hypoglycaemic episodes with M+S combination compared to all other metformin-antidiabetic agent combinations. Results for M+S versus metformin monotherapy were inconclusive. There were no RCTs comparing M+S with metformin plus insulin. We identified nine ongoing trials and two trials are awaiting assessment. Together these trials will include approximately 16,631 participants.

AUTHORS' CONCLUSIONS

There is inconclusive evidence whether M+S combination therapy compared with metformin plus another glucose-lowering intervention results in benefit or harm for most patient-important outcomes (mortality, SAEs, macrovascular and microvascular complications) with the exception of hypoglycaemia (more harm for M+S combination). No RCT reported on health-related quality of life.

Efficacy of different antidiabetic drugs based on metformin in the treatment of type 2 diabetes mellitus: A network meta-analysis involving eight eligible randomized-controlled trials

Diabetes mellitus is one of the most prevalent metabolic diseases globally and it is increasing in prevalence. It is one of the most expensive diseases with respect to total health care costs per patient as a result of its chronic nature and its severe complications. To provide a more effective treatment of type 2 diabetes mellitus (T2DM), this study aims to compare different efficacies of six kinds of hypoglycemic drugs based on metformin, including glimepiride, pioglitazone, exenatide, glibenclamide, rosiglitazone, and vildagliptin, in T2DM by a network meta-analysis that were verified by randomized-controlled trials (RCTs). Eight eligible RCT in consistency with the aforementioned six hypoglycemic drugs for T2DM were included. The results of network meta-analysis demonstrated that the exenatide + metformin and vildagliptin + metformin regimens presented with better efficacy. Patients with T2DM with unsatisfactory blood glucose control based on diet control, proper exercise, and metformin treatment were included. The original regimen and dose of medication were unchanged, followed by the addition of glimepiride, pioglitazone, exenatide, glibenclamide, rosiglitazone, and vildagliptin. The results of RCTs showed that all these six kinds of drugs reduced the HbA1c level. Compared with other regimens, exenatide + metformin reduced fasting plasma glucose (FPG), fasting plasma insulin (FPI), total cholesterol (TC), and homeostasis model assessment insulin resistance index (HOMA-IR) levels, but increased the high-density lipoprotein (HDL) level; vildagliptin + metformin decreased FPI and low-density lipoprotein (LDL) levels; glibenclamide + metformin decreased the FPG level, but promoted HDL; and glimepiride + metformin decreased the TC level and rosiglitazone + metformin reduced the LDL level. Our findings indicated that exenatide + metformin and vildagliptin + metformin have better efficacy in T2DM since they can improve insulin sensitivity.

Effects of canagliflozin versus glimepiride on adipokines and inflammatory biomarkers in type 2 diabetes

OBJECTIVE

Type 2 diabetes and obesity are pro-inflammatory states associated with increased risk of cardiovascular disease. Canagliflozin, an SGLT2 inhibitor, demonstrated superiority in lowering HbA1c versus glimepiride with less hypoglycemia and greater weight reduction via loss of fat mass in a 52-week trial of type 2 diabetes patients. This post hoc, exploratory analysis assessed the effects of canagliflozin versus glimepiride on select adipokines, inflammatory biomarkers, and chemokines.

METHODS

Changes from baseline to Week 52 in serum leptin, adiponectin, IL-6, TNFα, CRP, PAI-1, VCAM-1, and MCP-1 were measured in a randomly selected subset of type 2 diabetes patients on metformin receiving canagliflozin 300 mg (n = 100) or glimepiride (n = 100) in the overall study. Correlations between change in biomarkers and change in select metabolic and anthropometric variables were assessed.

RESULTS

At Week 52, canagliflozin decreased median serum leptin by 25% (95% CI: -34%, -15%) and increased median serum adiponectin by 17% (95% CI: 11%, 23%) compared with glimepiride. There was a 22% reduction in median serum IL-6 (95% CI: -34%, -10%) and a 7% increase in median serum TNFα (95% CI: 1%, 12%) with canagliflozin versus glimepiride. No between-group differences were observed with the other biomarkers. The decrease in serum leptin with canagliflozin was correlated with change in weight (r ≥ 0.3) only; the increase in adiponectin and decrease in IL-6 with canagliflozin occurred independently of changes in HbA1c, weight, or lipids.

CONCLUSIONS

These results indicate that canagliflozin may improve adipose tissue function and induce changes in serum leptin, adiponectin, and IL-6 that favorably impact insulin sensitivity and cardiovascular disease risk.

Brain GLP-1/IGF-1 Signaling and Autophagy Mediate Exendin-4 Protection Against Apoptosis in Type 2 Diabetic Rats

Type 2 diabetes (T2D) is a modern socioeconomic burden, mostly due to its long-term complications affecting nearly all tissues. One of them is the brain, whose dysfunctional intracellular quality control mechanisms (namely autophagy) may upregulate apoptosis, leading to cognitive dysfunction and Alzheimer disease (AD). Since impaired brain insulin signaling may constitute the crosslink between T2D and AD, its restoration may be potentially therapeutic herein. Accordingly, the insulinotropic anti-T2D drugs from glucagon-like peptide-1 (GLP-1) mimetics, namely, exendin-4 (Ex-4), could be a promising therapy. In line with this, we hypothesized that peripherally administered Ex-4 rescues brain intracellular signaling pathways, promoting autophagy and ultimately protecting against chronic T2D-induced apoptosis. Thus, we aimed to explore the effects of chronic, continuous, subcutaneous (s.c.) exposure to Ex-4 in brain cortical GLP-1/insulin/insulin-like growth factor-1 (IGF-1) signaling, and in autophagic and cell death mechanisms in middle-aged (8 months old), male T2D Goto-Kakizaki (GK) rats. We used brain cortical homogenates obtained from middle-aged (8 months old) male Wistar (control) and T2D GK rats. Ex-4 was continuously administered for 28 days, via s.c. implanted micro-osmotic pumps (5 μg/kg/day; infusion rate 2.5 μL/h). Peripheral characterization of the animal models was given by the standard biochemical analyses of blood or plasma, the intraperitoneal glucose tolerance test, and the heart rate. GLP-1, insulin, and IGF-1, their downstream signaling and autophagic markers were evaluated by specific ELISA kits and Western blotting. Caspase-like activities and other apoptotic markers were given by colorimetric methods and Western blotting. Chronic Ex-4 treatment attenuated peripheral features of T2D in GK rats, including hyperglycemia and insulin resistance. Furthermore, s.c. Ex-4 enhanced their brain cortical GLP-1 and IGF-1 levels, and subsequent signaling pathways. Specifically, Ex-4 stimulated protein kinase A (PKA) and phosphoinositide 3-kinase (PI3K)/Akt signaling, increasing cGMP and AMPK levels, and decreasing GSK3β and JNK activation in T2D rat brains. Moreover, Ex-4 regulated several markers for autophagy in GK rat brains (as mTOR, PI3K class III, LC3 II, Atg7, p62, LAMP-1, and Parkin), ultimately protecting against apoptosis (by decreasing several caspase-like activities and mitochondrial cytochrome c, and increasing Bcl2 levels upon T2D). Altogether, this study demonstrates that peripheral Ex-4 administration may constitute a promising therapy against the chronic complications of T2D affecting the brain.

Rahim AA, Eliana F, Shrestha HK, Chaudhary S, Ngugi N, Mbanya JC, Aye TT, Latt TS, Akanov ZA, Syed AR, Tandon N, Unnikrishnan AG, Madhu SV, Jawa A, Chowdhury S, Bajaj S, Das AK. Consensus Recommendations on Sulfonylurea and Sulfonylurea Combinations in the Management of Type 2 Diabetes Mellitus - International Task Force

For decades, sulfonylureas (SUs) have been important drugs in the antidiabetic therapeutic armamentarium. They have been used as monotherapy as well as combination therapy. Focus on newer drugs and concerns about the risk of severe hypoglycemia and weight gain with some SUs have led to discussion on their safety and utility. It has to be borne in mind that the adverse events associated with SUs should not be ascribed to the whole class, as many modern SUs, such as glimepiride and gliclazide modified release, are associated with better safety profiles. Furthermore, individualization of treatment, using SUs in combination with other drugs, backed with careful monitoring and patient education, ensures maximum benefits with minimal side effects. The current guidelines, developed by experts from Africa, Asia, and the Middle East, promote the safe and smart use of SUs in combination with other glucose-lowering drugs.

Pharmacokinetic drug evaluation of exenatide for the treatment of type 2 diabetes

INTRODUCTION

Glucagon-like peptide-1 (GLP-1) receptor analogs are a group of therapeutic agents which mimic endogenous GLP-1, exerting their effect by the stimulation of the GLP-1 receptor with a wide distribution. Its activation increases insulin releasing dependent on blood glucose levels, suppression of glucagon secretion and a reduction of hepatic glucose output. It delays gastric emptying and increases satiety. Exenatide is the synthetic version of exendin-4, a natural peptide with similar properties to human GLP-1. There are two pharmaceutical forms, for subcutaneous injection: twice daily and once weekly. Clinical practice guidelines recommend them because of a high efficacy reducing hyperglycemia, low risk of hypoglycemia and a significative weight loss effect. Gastrointestinal adverse events are the most common beside injection site-related. Their cost is the main limitation to use. Areas covered: We review the recent literature investigating the pharmacokinetics and pharmacodynamics and efficacy-safety studies of exenatide twice daily and once weekly in type 2 diabetes Expert opinion: GLP-1 receptor analogs are now positioned as an effective and safe drug for the treatment of type 2 diabetes. Exenatide significally reduces HbA1c and fasting plasma glucose. Additionally, it produces moderate weight loss and decreases blood pressure. One weekly formulation may improve compliance while cost is still a limitation. EXSCEL trial has shown that, despite cardiovascular safety, exenatide do not exhibits cardiovascular benefits.

Network meta-analysis of lorcaserin and oral hypoglycaemics for patients with type 2 diabetes mellitus and obesity

In addition to weight loss, randomized controlled trials have shown improvement in glycaemic control in patients taking lorcaserin. The aim of this study aim was to compare adding lorcaserin or other glucose lowering medications to metformin on weight and glycaemic control. A systematic review and network meta-analysis of randomized controlled trials were conducted. Included studies (published 1990-2014) were of lorcaserin or glucose lowering medications in type 2 diabetic patients compared to placebo or different active treatments. Studies had to report ≥1 key outcome (change in weight or HbA1c, % HbA1c <7, hypoglycaemia). Direct meta-analysis was performed using DerSimonian and Laird random effects models, and network meta-analysis with Bayesian Markov-chain Monte Carlo random effects models; 6552 articles were screened and 41 included. Lorcaserin reduced weight significantly more than thiazolidinediones, glinides, sulphonylureas and dipeptidyl peptidase-4 inhibitors, some of which may have led to weight gain. There were no significant differences in weight change between lorcaserin and alpha-glucoside inhibitors, glucagon-like peptide-1 agonists and sodium/glucose cotransporter 2 inhibitors. Network meta-analysis showed lorcaserin was non-inferior to all other agents on HbA1c reduction and % achieving HbA1c of <7%. The risk of hypoglycaemia was not significantly different among studied agents except that sulphonylureas were associated with higher risk of hypoglycaemia than lorcaserin. Although additional studies are needed, this analysis suggests in a population of patients with a body mas index of ≥27 who do not achieve glycaemic control on a single agent, lorcaserin may be added as an alternative to an add-on glucose lowering medication.

Evaluating the costs of glycemic response with canagliflozin versus dapagliflozin and empagliflozin as add-on to metformin in patients with type 2 diabetes mellitus in the United Arab Emirates

OBJECTIVE

This study evaluates the cost of achieving glycemic control with three sodium glucose co-transporter 2 (SGLT2) inhibitors, canagliflozin, dapagliflozin, and empagliflozin, in patients with type 2 diabetes mellitus (T2DM) from the payer perspective in the United Arab Emirates (UAE).

METHODS

A systematic literature review identified randomized controlled trials of antihyperglycemic agents as add-on to metformin in patients with T2DM of 26 ± 4 weeks in duration, published by 10 September 2014. A Bayesian network-meta analysis (NMA) compared HbA1c changes with canagliflozin 100 and 300 mg versus dapagliflozin 10 mg and empagliflozin 10 and 25 mg. The cost associated with a 1% placebo-adjusted HbA1c reduction with each SGLT2 inhibitor as add-on to metformin was calculated based on NMA results and UAE drug costs.

RESULTS

In the NMA, canagliflozin 100 and 300 mg were associated with HbA1c reductions (-0.67% and -0.79%) compared with dapagliflozin 10 mg (-0.41%) and empagliflozin 10 and 25 mg (-0.57% and -0.64%). Probabilities of canagliflozin 100 mg performing better were 79%, 60%, and 53% versus dapagliflozin 10 mg and empagliflozin 10 and 25 mg, respectively; probabilities for canagliflozin 300 mg performing better were 88%, 72%, and 65%, respectively. The cost per 1%-point reduction in HbA1c was projected to be lower with canagliflozin 100 and 300 mg ($448 and $422) compared with dapagliflozin 10 mg ($785) and empagliflozin 10 and 25 mg ($527 and $563).

CONCLUSIONS

Canagliflozin may provide a greater glycemic response at a lower effective cost than dapagliflozin or empagliflozin for patients with T2DM inadequately controlled with metformin from the payer perspective in the UAE.

The Role of Glucagon-like Peptide-1 Receptor Agonists in the Treatment of Type 2 Diabetes

The role of GLP-1 agonists in the treatment of type 2 diabetes have been shown to be viable options for add-on therapy in diabetic patients, as well as potential monotherapy options. With six available GLP-1 agents, and new combination products in the pipeline, they are a promising drug class for type 2 diabetic patients, especially due to their extended dosing interval and potential weight loss benefits.

Glucagon-like peptide-1 receptor agonists: a systematic review of comparative effectiveness research

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) act by increasing insulin secretion, decreasing glucagon secretion, slowing gastric emptying, and increasing satiety.

OBJECTIVE

Published evidence directly comparing GLP-1RAs with other approved treatments for type 2 diabetes (T2D) was systematically reviewed.

METHODS

A literature search was performed using MEDLINE and Embase databases to identify papers comparing GLP-1RAs with other classes of glucose-lowering therapy in patients with T2D.

RESULTS

Of the 1303 papers identified, 57 met the prespecified criteria for a high-quality clinical trial or retrospective study. The efficacy and tolerability of approved GLP-1RAs (exenatide twice daily or once weekly, dulaglutide, liraglutide, lixisenatide, and albiglutide) were compared with insulin products (23 prospective studies + seven retrospective studies), dipeptidyl peptidase-4 inhibitors (11 prospective studies + three retrospective studies), sulfonylureas (nine prospective studies + one retrospective study), thiazolidinediones (five prospective studies), and metformin (two prospective studies). GLP-1RAs are effective as a second-line therapy in improving glycemic parameters in patients with T2D. Reductions in glycated hemoglobin from baseline with GLP-1RAs tended to be greater or similar compared with insulin therapy. GLP-1RAs were consistently more effective in reducing body weight than most oral glucose-lowering drugs and insulin and were associated with lower hypoglycemia risk versus insulin or sulfonylureas. GLP-1RAs improved cardiovascular risk factors, and preliminary data suggest they improve cardiovascular outcomes in patients with T2D compared with oral glucose-lowering drugs. However, results from ongoing studies are awaited to confirm these early findings.

CONCLUSION

This systematic review found that GLP-1RAs are an effective class of glucose-lowering drugs for T2D.

Glucagon-like peptide-1 receptor agonists in the treatment of type 2 diabetes: Past, present, and future

Glucagon-like peptide-1 (GLP-1)-based therapy improves glycaemic control through multiple mechanisms, with a low risk of hypoglycaemia and the additional benefit of clinically relevant weight loss. Since Starling and Bayliss first proposed the existence of intestinal secretions that stimulate the pancreas, tremendous progress has been made in the area of incretins. As a number of GLP-1 receptor agonists (GLP-1 RAs) continue to become available, physicians will soon face the challenge of selecting the right option customized to their patient's needs. The following discussion, derived from an extensive literature search using the PubMed database, applying the terms incretin, GLP-1, exenatide, liraglutide, albiglutide, dulaglutide, lixisenatide, semaglutide, and taspoglutide, provides a comprehensive review of existing and upcoming molecules in the GLP-1 RA class in terms of their structure, pharmacological profiles, efficacy, safety, and convenience. Search Methodology: A literature search was conducted using the PubMed database, applying the terms incretin, GLP-1, exenatide, liraglutide, albiglutide, dulaglutide, lixisenatide, semaglutide, and taspoglutide. Relevant articles were those that discussed structural, pharmacokinetic and pharmacodynamic differences, classification, long-acting and short-acting GLP-1 RAs, phase 3 trials, and expert opinions. Additional targeted searches were conducted on diabetes treatment guidelines and reviews on safety, as well as the American Diabetes Association/European Society for Study of Diabetes (ADA/EASD) statement on pancreatic safety.

A Network Meta-analysis Comparing Exenatide Once Weekly with Other GLP-1 Receptor Agonists for the Treatment of Type 2 Diabetes Mellitus

INTRODUCTION

Exenatide is a glucagon-like peptide-1 receptor agonist (GLP-1 RA), approved for treatment of type 2 diabetes mellitus (T2DM). There is limited direct evidence comparing the efficacy and tolerability of exenatide 2 mg once weekly (QW) to other GLP-1 RAs. A network meta-analysis (NMA) was conducted to estimate the relative efficacy and tolerability of exenatide QW versus other GLP-1 RAs for the treatment of adults with T2DM inadequately controlled on metformin monotherapy.

METHODS

A systematic literature review was conducted to identify randomized controlled trials (RCTs) that investigated GLP-1 RAs (albiglutide, dulaglutide, exenatide, liraglutide, and lixisenatide) at approved doses in the United States/Europe, added on to metformin only and of 24 ± 6 weeks treatment duration. A Bayesian NMA was conducted.

RESULTS

Fourteen RCTs were included in the NMA. Exenatide QW obtained a statistically significant reduction in glycated hemoglobin (HbA1c) relative to lixisenatide 20 µg once daily. No other comparisons of exenatide QW to other GLP-1 RAs were statistically significant for change in HbA1c. No statistically significant differences in change in weight, systolic blood pressure, risk of nausea or discontinuation due to adverse events were observed for exenatide QW versus other GLP-1 RAs.

CONCLUSION

Exenatide QW demonstrated similar effectiveness and tolerability compared to other GLP-1 RAs, for the treatment of T2DM in adults inadequately controlled on metformin alone.

Treatment potential of the GLP-1 receptor agonists in type 2 diabetes mellitus: a review

Over the last decade, the discovery of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) has increased the treatment options for patients with type 2 diabetes mellitus (T2DM). GLP-1 RAs mimic the effects of native GLP-1, which increases insulin secretion, inhibits glucagon secretion, increases satiety and slows gastric emptying. This review evaluates the phase III trials for all approved GLP-1 RAs and reports that all GLP-1 RAs decrease HbA1c, fasting plasma glucose, and lead to a reduction in body weight in the majority of trials. The most common adverse events are nausea and other gastrointestinal discomfort, while hypoglycaemia is rarely reported when GLP-1 RAs not are combined with sulfonylurea or insulin. Treatment options in the near future will include co-formulations of basal insulin and a GLP-1 RA.

Exenatide twice daily: a review of its use in the management of patients with type 2 diabetes mellitus

Exenatide, administered subcutaneously twice daily (Byetta(®)), is a synthetic version of the natural peptide exendin-4, which is a glucagon-like peptide-1 (GLP-1) receptor agonist (incretin mimetic). Exenatide binds to the GLP-1 receptor with the same affinity as GLP-1, but has a much longer half-life, since it is not degraded by the enzyme dipeptidyl peptidase-4. Exenatide twice daily enhances glucose-dependent insulin secretion, suppresses inappropriately elevated glucagon secretion, slows gastric emptying and reduces caloric intake. In well-designed clinical trials, adjunctive subcutaneous exenatide 5 or 10 μg twice daily for 16-52 weeks significantly and dose-dependently improved glycaemic control and reduced mean body weight compared with placebo in patients with type 2 diabetes inadequately controlled with oral antihyperglycaemic drugs (OADs) and/or basal insulin. The improvements in glycaemic control and reductions in body weight were stably maintained during long-term therapy (up to 3.5 years). The efficacy of adjunctive exenatide twice daily was generally similar to that of basal, prandial or biphasic insulin, sulfonylureas, rosiglitazone and lixisenatide, and less than that of liraglutide, taspoglutide or exenatide once weekly with respect to reductions in glycated haemoglobin. Exenatide twice daily was generally well tolerated; mild to moderate nausea and vomiting, which decreased with time on therapy, were the most common adverse events. In patients not receiving concomitant sulfonylureas or insulin, the incidence of hypoglycaemia was low; when it did occur, it was generally mild in severity. Thus, adjunctive exenatide twice daily is a valuable option in the treatment of type 2 diabetes inadequately controlled with OADs and/or basal insulin.

Sulfonylureas and their use in clinical practice

Many anti-diabetic drugs with different mechanisms of action are now available for treatment of type 2 diabetes mellitus. Sulfonylureas have been extensively used for treatment of type 2 diabetes for nearly 50 years and, even in our times, are widely used for treatment of this devastating chronic illness. Here, we review some of the available data on sulfonylureas, evaluating their mechanism of action and their effects on glycemic control. We can conclude that sulfonylureas are still the most used anti-diabetic agents: maybe this is due to their lower cost, to the possibility of mono-dosing and to the presence of an association with metformin in the same tablet. However, sulfonylureas, especially the older ones, are linked to a greater prevalence of hypoglycemia, and cardiovascular risk; newer prolonged-release preparations of sulfonylureas are undoubtedly safer, mainly due to reducing hypoglycemia, and for this reason should be preferred.

The Effect of Glucagon-Like Peptide 1 Receptor Agonists on Weight Loss in Type 2 Diabetes: A Systematic Review and Mixed Treatment Comparison Meta-Analysis

AIMS

To determine the effects of glucagon-like peptide-1 receptor agonists compared with placebo and other anti-diabetic agents on weight loss in overweight or obese patients with type 2 diabetes mellitus.

METHODS

Electronic searches were conducted for randomised controlled trials that compared a glucagon-like peptide-1 receptor agonist therapy at a clinically relevant dose with a comparator treatment (other type 2 diabetes treatment or placebo) in adults with type 2 diabetes and a mean body mass index ≥ 25 kg/m2. Pair-wise meta-analyses and mixed treatment comparisons were conducted to examine the difference in weight change at six months between the glucagon-like peptide-1 receptor agonists and each comparator.

RESULTS

In the mixed treatment comparison (27 trials), the glucagon-like peptide-1 receptor agonists were the most successful in terms of weight loss; exenatide 2 mg/week: -1.62 kg (95% CrI: -2.95 kg, -0.30 kg), exenatide 20 μg: -1.37 kg (95% CI: -222 kg, -0.52 kg), liraglutide 1.2 mg: -1.01 kg (95%CrI: -2.41 kg, 0.38 kg) and liraglutide 1.8 mg: -1.51 kg (95% CI: -2.67 kg, -0.37 kg) compared with placebo. There were no differences between the GLP-1 receptor agonists in terms of weight loss.

CONCLUSIONS

This review provides evidence that glucagon-like peptide-1 receptor agonist therapies are associated with weight loss in overweight or obese patients with type 2 diabetes with no difference in weight loss seen between the different types of GLP-1 receptor agonists assessed.

Glucagon-like polypeptide agonists in type 2 diabetes mellitus: efficacy and tolerability, a balance

Glucagon-like polypeptide (GLP-1) receptor agonist treatment has multiple effects on glucose metabolism, supports the β cell, and promotes weight loss. There are now five GLP-1 agonists in clinical use with more in development. GLP-1 treatment typically can induce a lowering of hemoglobin A1c (HbA1c) of 0.5-1.5% over time with weight loss of 2-5%. In some individuals, a progressive loss of weight occurs. There is evidence that GLP-1 therapy opposes the loss of β cells which is a feature of type 2 diabetes. The chief downside of GLP-1 treatment is the gastrointestinal motility disturbance which is one of the modes of action of the hormone; significant nausea, vomiting, and diarrhea may lead to discontinuation of treatment. Although daily injection of GLP-1 agents is successful, the development of extended release preparations allows for injection once weekly, and perhaps much longer in the future. The indication for GLP-1 use is diabetes, but now, liraglutide has been approved for primary treatment of obesity. When oral agents fail to control glucose levels in type 2 diabetes, there is a choice between long-acting insulin and GLP-1 agonists as additional treatments. The lowering of HbA1c by either modality is equivalent in most studies. Patients lose weight with GLP-1 treatment and gain weight on insulin. There is a lower incidence of hypoglycemia with GLP-1 therapy but a much higher incidence of gastrointestinal complaints. Insulin dosing is flexible while GLP-1 agents have historically been administered at fixed dosages. Now, the use of combined long-acting insulin and GLP-1 agonists is promising a major therapeutic change. Combined therapy takes advantage of the benefits of both insulin and GLP-1 agents. Furthermore, direct admixture of both in the same syringe will permit flexible dosing, improvement of glucose levels, and reduction of both hypoglycemia and gastrointestinal side effects.

Efficacy and tolerability of glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes mellitus

Glucagon-like peptide-1 (GLP-1) has been evaluated for use in the treatment of type 2 diabetes mellitus (T2DM) due to its role in glucose regulation. Four GLP-1 receptor agonists (RAs) are currently indicated for T2DM in the USA. Exenatide and liraglutide are short-acting and require twice-daily and daily dosing, respectively. Two longer acting agents, exenatide long-acting release (LAR) and albiglutide, were formulated to allow for once-weekly dosing. All four GLP-1 RAs have demonstrated reductions in hemoglobin A1c, fasting blood glucose, and body weight both as monotherapy and in combination with first- and second-line diabetes agents including metformin, sulfonylureas, thiazolidinediones, and insulin. Greater glycemic control was seen with liraglutide compared with the other GLP-1 treatment options; however, the two long-acting agents were superior to exenatide twice daily. All agents were well tolerated with most adverse events being mild or moderate in nature. The most common adverse event was transient nausea which typically resolved 4-8 weeks after treatment initiation. Long-acting agents had lower rates of nausea but an increased incidence of injection site reactions. Trials have suggested GLP-1 RAs may improve cardiovascular risk factors including blood pressure, lipid parameters and inflammatory markers. Future trials are needed to confirm the clinical outcomes of these agents. Overall, GLP-1 RAs will provide benefit for patients with T2DM intolerable to or not reaching glycemic goals with first-line agents, especially in patients in need of weight loss.

Observational and clinical trial findings on the comparative effectiveness of diabetes drugs showed agreement

OBJECTIVES

This study compares an observational study of diabetes treatment effectiveness to randomized controlled trials to assess their convergent validity.

STUDY DESIGN AND SETTING

Multivariate models were developed using observational data to describe change in hemoglobin A1c (HbA1c; % unit) and weight (kilograms) after addition of a second-line oral diabetes drug to metformin monotherapy. Randomized trials of these scenarios were systematically identified. The models were used to simulate each trial, and simulated and actual results were compared by linear regression and meta-analysis.

RESULTS

Thirty-two randomized trials of second-line diabetes oral therapy were identified. For all outcomes and drugs studied, simulation and actual results correlated (P < 0.001). There were no statistically significant differences between meta-analyzed randomized and simulated results for effect on HbA1c. For effect on weight, results were qualitatively comparable, but for sulfonylureas, the simulated weight gain was nominally greater than seen in the randomized controlled trials.

CONCLUSION

An observational study of diabetes drug effectiveness showed convergent validity with randomized data. This supports cautious use of the observational research to draw conclusions about drug effectiveness in populations not studied in clinical trials. This approach may be useful in other situations where observational and randomized data need integration.

Exenatide enhances INS-1 rat pancreatic β‑cell mass by increasing the protein levels of adiponectin and reducing the levels of C-reactive protein

Type 2 diabetes mellitus (T2DM) is a complex and heterogeneous disorder affecting >220 million individuals worldwide; this is projected to reach 366 million by 2030. Exenatide, a long‑acting glucagon‑like peptide 1 receptor agonist, exhibits potential in the treatment of T2MD due to its ability to increase β‑cell mass. However, the molecular mechanism by which exenatide increases β‑cell mass is yet to be elucidated. Exenatide function was explored in the INS‑1 rat pancreatic β‑cell line. Exenatide was found to increase adiponectin protein levels by 20% (P<0.05 versus the control group) and reduce the level of C‑reactive protein (CRP) by 50% (P<0.01 versus the control group) in INS‑1 cells, resulting in an increase in the INS‑1 rat pancreatic β‑cell mass by 20% (P<0.01 versus the control group). These findings suggest that exenatide may ameliorate T2DM by increasing adiponectin protein levels and reducing the level of CRP.

Dapagliflozin compared with other oral anti-diabetes treatments when added to metformin monotherapy: a systematic review and network meta-analysis

AIMS

Indirect evidence from randomized controlled trials (RCTs) was used to estimate the effect of dapagliflozin, a new agent with a novel mechanism of action (SGLT-2 inhibition), relative to other anti-diabetes therapies after 1 year of treatment.

METHODS

A systematic literature review and Bayesian network meta-analysis (NMA) of RCTs involving anti-diabetes treatments added to metformin were conducted. RCTs enrolling subjects with type 2 diabetes inadequately controlled on metformin monotherapy were included. Comparators included dipeptidyl peptidase-4 (DPP-4) inhibitors, thiazolidinediones (TZDs), sulphonylureas, glucagon-like peptide-1 (GLP-1) analogues and dapagliflozin. Outcomes of interest were mean change from baseline HbA1c, weight and systolic blood pressure, and incidence of hypoglycaemia.

RESULTS

From 4270 abstracts, six RCTs were included in the primary analysis; no RCTs involving GLP-1 analogues met primary inclusion criteria. All RCTs were actively controlled with sulphonylureas. The mean change in HbA1c from baseline was similar across comparators. The treatment effect (95% credible interval) of dapagliflozin on HbA1c was -0.08% (-0.25, 0.10) relative to DPP-4 inhibitors, -0.02% (-0.24, 0.21) relative to TZDs and 0.00% (-0.16, 0.16) relative to sulphonylureas. Non-sulphonylureas showed significantly lower risk of hypoglycaemia relative to sulphonylureas. Dapagliflozin had a significant effect on weight change: the relative difference was -2.74 kg (-5.35, -0.10) compared with DPP-4 inhibitors, and -4.67 kg (-7.03, -2.35) compared with sulphonylureas. Systolic blood pressure was not meta-analysed due to infrequent reporting.

CONCLUSION

Compared with DPP-4 inhibitors, TZDs and sulphonylureas, dapagliflozin offers similar HbA1c control after 1 year, with similar or reduced risk of hypoglycaemia and the additional benefit of weight loss, when added to metformin.

Beneficial effects of liraglutide on adipocytokines, insulin sensitivity parameters and cardiovascular risk biomarkers in patients with Type 2 diabetes: a prospective study

AIMS

To evaluate the effects of liraglutide after 14 weeks of treatment on serum adipokines, insulin resistance index and cardiovascular risk biomarkers in overweight or obese T2DM patients unable to achieve glycemic control with metformin alone or in association with a sulfonylurea in daily clinical practice.

METHODS

Prospective study in 59 consecutive overweight or obese (BMI≥25kg/m(2)) T2DM patients unable to achieve glycemic control (HbA1c>7%, 53mmol/mol) with metformin alone or in association with sulfonylurea that require initiation of liraglutide in progressive dose increase up to 1.8mg/day subcutaneously. Weight, body composition, blood pressure, glucose, HbA1c, C-peptide, insulin, plasma lipids, adipokines (leptin, adiponectin, resistin and visfatin) as well as cardiovascular biomarkers (IL-6 and TNF-a) levels were measured fasting at baseline and 14 weeks after liraglutide initiation.

RESULTS

14 weeks of liraglutide treatment significantly reduced HbA1c, BMI and total body fat mass by 0.9%, 1.4kg/m(2) and 0.5% respectively. Statistically significant lower insulin resistance and higher insulin secretion was found by HOMA-IR 8.4 (1.6) vs 4.6 (0.9)molmIU/L(2) and HOMA-B 48.2 (9.0) vs 87.6 (16.3)μIU/mmol. Statistically significantly higher levels of visfatin 6.3 (2.1) vs 6.8 (2.1)ng/ml and resistin 3.6 (2.0) vs 4.3 (2.3)ng/ml were also observed after treatment. Baseline visfatin was negatively correlated with basal fasting plasma glucose r=-0.360 (p<0.05).

CONCLUSIONS

Liraglutide treatment for 14 weeks in daily clinical practice led to reduction of BMI and improvement of glucose control and insulin sensitivity and resistance parameters. Additionally, circulating levels of adipokines and pro-inflammatory factors could play an important role in GLP-1 treatment response.

Possible effects of glimepiride beyond glycemic control in patients with type 2 diabetes: a preliminary report

Background

The purpose of this study was to elucidate the effects of glimepiride on the levels of biomarkers related to cardiovascular regulation in patients with type 2 diabetes mellitus.

Methods and results

Thirty-four patients with type 2 diabetes received glimepiride for 24 weeks. Significant decreases in the levels of glyceraldehyde-derived advanced glycation end products, (glycer-AGE: toxic AGE), eotaxin and fibroblast growth factor (FGF)-2 were recognized after the administration of glimepiride. Moreover, there were trends for there to be increases in the levels of granulocyte-colony stimulating factor (G-CSF) and granulocyte macrophage-colony stimulating factor (GM-CSF), and decreases in the levels of fractalkine, soluble CD40 ligand (sCD40L), macrophage inflammatory protein (MIP)-β, vascular endothelial growth factor (VEGF) and soluble receptor for AGE (sRAGE).

Conclusions

Glimepiride may have potent anti-oxidative, anti-inflammatory and angiogenic properties and it may potentially repair tissue damage by decreasing the levels of toxic AGE and increasing colony-stimulating factors.

Early use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in type 2 diabetes

OBJECTIVE

To evaluate the efficacy and safety of the available glucagon-like peptide-1 receptor agonists (GLP-1 RAs) exenatide and liraglutide (marketed as Byetta * and Victoza † , respectively) in first- or second-line pharmacotherapy for type 2 diabetes (T2D), described here as 'early use'.

RESEARCH DESIGN AND METHODS

MEDLINE, EMBASE and Google Scholar databases were queried for clinical trial reports using the terms incretin, GLP-1, exenatide and liraglutide. Relevant articles were those that employed these agents in treatment-naïve patients with T2D and in patients who had failed on metformin monotherapy. Additional targeted searches were conducted on diabetes treatment guidelines and on the range of physiological responses to GLP-1 RAs. Most evidence is level I and II.

RESULTS

Effective therapy for T2D should be implemented early in the course of this progressive disease. The recently revised 2013 Canadian Diabetes Association (CDA) guidelines now identify the GLP-1 RAs among various injected and oral agents recommended for the management of T2D. The rationale for early use of GLP-1 RAs in T2D management is manifold: these agents offer effective management of hyperglycemia in early-stage T2D, minimal risk of hypoglycemia, weight loss, improvement in multiple non-glycemic cardiovascular risk factors, and potential enhancement of patient adherence to antihyperglycemic treatment. Available data from clinical trials support second-line use of GLP-1 RAs among patients who fail on metformin, as well as first-line use of these agents in a subset of T2D patients.

CONCLUSIONS

The ability to achieve glycemic targets using GLP-1 RAs while simultaneously avoiding hypoglycemia and weight gain could provide substantial reassurance to physicians and patients who might otherwise resist the transition to injected therapies. Exenatide and liraglutide represent appropriate second-line choices for pharmacological treatment of T2D, as indicated in the 2013 CDA guidelines.

Differential effects of GLP-1 receptor agonists on components of dysglycaemia in individuals with type 2 diabetes mellitus

Metabolic consequences of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are the result of enhanced glucose-stimulated insulin secretion, inhibition of glucagon release, delayed gastric emptying and increased satiety. These attributes make GLP-1 agonists a treatment option in type 2 diabetes mellitus (T2DM). To optimise treatment choice, a detailed understanding of the effects of GLP-1 RAs on glucose homeostasis in individuals with T2DM is necessary. Although the various GLP-1 RAs share the same basic mechanisms of action, differences in pharmacokinetic/pharmacodynamic characteristics translate into differential effects on parameters of glycaemia. Head-to-head comparisons between long-acting non-prandial (liraglutide once daily and exenatide once weekly) and shorter-acting prandial (exenatide twice daily and lixisenatide once daily prandial) GLP-1 RAs confirm their differential effects on fasting plasma glucose (FPG) and post-prandial glucose (PPG). Liraglutide once daily and exenatide once weekly demonstrate greater reductions in FPG but lesser impacts on PPG excursions plasma than exenatide twice daily. Prandial GLP-1 RAs have a profound effect on post-prandial glycaemia, mediated by delaying gastric emptying, which is not subject to the tachyphylaxis occurring due to the sustained elevated plasma GLP-1 concentrations after treatment with long-acting GLP-1 RAs. Lixisenatide once-daily prandial, in contrast to liraglutide, strongly suppresses post-prandial glucagon secretion, further contributing to the more pronounced PPG-lowering effect found with lixisenatide. Evidence suggests that the GLP-1 RAs that predominantly target the prandial glucose excursions, such as exenatide twice daily and lixisenatide once-daily prandial, are therefore best used as combination therapy with basal insulin and will form an important new treatment option for individuals with T2DM.

Cardiovascular safety of sulfonylureas: a meta-analysis of randomized clinical trials

AIM

Cardiovascular safety of sulfonylurea has been questioned by some authors. This article aims at collecting all available data on this issue from randomized trials.

METHODS

A meta-analysis was performed including all trials with a duration of at least 6 months, comparing a sulfonylurea with a non-sulfonylurea agent in type 2 diabetes. Major cardiovascular events (MACE) and mortality were retrieved and combined to calculate Mantel-Haenzel odds ratio (MH-OR).

RESULTS

Of the 115 selected trials, 62 reported information on MACE, and 30 reported at least one event. MH-OR for sulfonylurea was 1.08 [0.86-1.36], p = 0.52 (1.85 [1.20-2.87], p = 0.005, in the five trials vs. DPP4 inhibitors, no significant differences vs. other comparators). The MH-OR for myocardial infarction and stroke was 0.88 [0.75-1.04], p = 0.13 and 1.28 [1.03-1.60], p = 0.026, respectively. Mortality was significantly increased with sulfonylureas (MH-OR: 1.22 [1.01-1.49], p = 0.047).

CONCLUSIONS

In type 2 diabetes, the use of sulfonylureas is associated with increased mortality and a higher risk of stroke, whereas the overall incidence of MACE appears to be unaffected. Significant differences in cardiovascular risk could be present in direct comparisons with specific classes of glucose-lowering agents, such as DPP4 inhibitors, but this hypothesis needs to be confirmed in long-term cardiovascular outcomes trials. The results of this meta-analysis need to be interpreted with caution, mainly because of limitations in trial quality and under-reporting of information on cardiovascular events and mortality. However, the cardiovascular safety of sulfonylureas cannot be considered established unless it is evaluated in long-term cardiovascular outcomes trials.

Effects of exenatide and metformin in combination on some adipocytokine levels: a comparison with metformin monotherapy

The aim of this study was to evaluate the effects of exenatide on levels of serum adipocytokines and on β-cell function. The study was conducted between 2008 and 2012. After a run-in period with metformin, 174 patients with type-2 diabetes were randomly distributed to either a group receiving exenatide at 10 μg twice daily, or a group receiving the placebo, for 12 months. We evaluated body mass index (BMI), blood pressure, glycemic control, lipid profile, fasting plasma insulin (FPI), HOMA-IR, HOMA-β, fasting plasma proinsulin (FPPr), proinsulin : fasting plasma insulin ratio (Pr/FPI ratio), C-peptide, glucagon, retinol binding protein-4 (RBP-4), visfatin, omentin-1, and microalbuminuria. We used ELISA methods to assess the various parameters. Patients also underwent a combined euglycemic-hyperinsulinemic and hyperglycemic clamp, with subsequent arginine stimulation. After 12 months, a combination of exenatide and metformin produced a better decrease in body mass, BMI, glycemic control, FPI, FPPr, FPPr/FPI ratio, HOMA-IR, and glucagon level. Treatment with exenatide + metformin was superior to the placebo + metformin in increasing HOMA-β, C-peptide, and β-cell function. Significant negative correlations were found between M value, an index of insulin sensitivity, and measured adipocytokines. In conclusion, the combination of exenatide + metformin plays a role in improving some adipocytokine levels, and is better than metformin alone. The significant negative correlation between M value and measured adipocytokines is another confirmation of the positive effects linked to the improvement in insulin sensitivity.

Current issues in GLP-1 receptor agonist therapy for type 2 diabetes

The clinical management of hyperglycemia in patients with type 2 diabetes mellitus (T2DM) is guided not only by published treatment algorithms, but also by consideration of recent evidence and through consultation with colleagues and experts. Recent studies have dramatically increased the amount of information regarding the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs). Topics that may be of particular interest to clinicians who treat T2DM patients include relative glycemic control efficacy of GLP-1 RAs, use of GLP-1 RAs across T2DM progression and in combination with insulin, recent data regarding GLP-1 RA safety, nonglycemic actions of GLP-1 RAs, including weight effects, and impact of GLP-1 RAs on patient quality of life and treatment satisfaction. The following review includes expert consideration of these topics with emphasis on recent, relevant reports to illustrate current perspectives.

Correlation between levels of circulating adipokines and adiponectin/resistin index with carotid intima-media thickness in hypertensive type 2 diabetic patients

BACKGROUND

Hypoadiponectinemia and hyperresistinemia are associated with cardiovascular disease. The increase in the carotid intima-media thickness (CIMT) assessed by B-mode ultrasound has been directly associated with increased risk of myocardial infarction and stroke.

OBJECTIVE

To evaluate the correlation between adipokine levels with CIMT in hypertensive type 2 diabetic patients.

METHODS

Serum levels of adiponectin and resistin levels were measured by ELISA in 30 type 2 diabetic patients with never-treated hypertension and in age-matched healthy controls. The CIMT (B-mode color imaging of extracranial carotid arteries using high-resolution ultrasound) was also obtained. The relationship between adipokine levels and the adiponectin/resistin index with the CIMT was assessed by the Pearson correlation coefficient test.

RESULTS

Adiponectin was lower (p < 0.05), and resistin higher (p < 0.01) in patients than in controls, CIMT correlated positively with resistin (R = 0.45, p < 0.02) and the adiponectin/resistin index (R = 0.58, p < 0.001), but not with adiponectin levels (r = -0.11, p > 0.1) in patients. Whereas only adiponectin levels correlated - negatively - with CIMT (r = -0.39, p < 0.02) in controls.

CONCLUSION

Our results shown that the adiponectin/resistin index seems to be more strongly associated with atherosclerosis than adipokine levels, and may be used as a reliable marker of cardiovascular risk in type 2 diabetic hypertensive patients.

Evolution of exenatide as a diabetes therapeutic

Type 2 diabetes (T2DM) is a disease of epidemic proportion associated with significant morbidity and excess mortality. Optimal glucose control reduces the risk of microvascular and possibly macrovascular complications due to diabetes. However, glycemic control is rarely optimal and several therapeutic interventions for the treatment of diabetes cause hypoglycemia and weight gain; some may exacerbate cardiovascular risk. Exenatide (synthetic exendin-4) is a glucagon- like peptide-1 receptor (GLP-1R) agonist developed as a first-in-class diabetes therapy. This review presents an overview of the evolution of exenatide as a T2DM treatment, beginning with the seminal preclinical discoveries and continuing through to clinical pharmacology investigations and phase 3 clinical trials. In patients with T2DM, exenatide enhanced glucose-dependent insulin secretion, suppressed inappropriately elevated glucagon secretion, slowed gastric emptying, and enhanced satiety. In controlled phase 3 clinical trials ranging from 12 to 52 weeks, 10-mcg exenatide twice daily (ExBID) reduced mean HbA1c by -0.8% to -1.7% as monotherapy or in combination with metformin (MET), sulfonylureas (SFU), and/or thiazolidinediones (TZD); with mean weight losses of -1.2 kg to -8.0 kg. In controlled phase 3 trials ranging from 24 to 30 weeks, a 2-mg once-weekly exenatide formulation (ExQW) reduced mean HbA1c by -1.3% to -1.9%, with mean weight reductions of -2.3 to -3.7 kg. Exenatide was generally well-tolerated. The most common side effects were gastrointestinal in nature, mild, and transient. Nausea was the most prevalent adverse event. The incidence of hypoglycemia was generally low. By building upon early observations exenatide was successfully developed into an effective diabetes therapy.

Effects of exenatide and liraglutide on heart rate, blood pressure and body weight: systematic review and meta-analysis

OBJECTIVES

To synthesise current evidence for the effects of exenatide and liraglutide on heart rate, blood pressure and body weight.

DESIGN

Meta-analysis of available data from randomised controlled trials comparing Glucagon-like peptide-1 (GLP-1) analogues with placebo, active antidiabetic drug therapy or lifestyle intervention.

PARTICIPANTS

Patients with type 2 diabetes.

OUTCOME MEASURES

Weighted mean differences between trial arms for changes in heart rate, blood pressure and body weight, after a minimum of 12-week follow-up.

RESULTS

32 trials were included. Overall, GLP-1 agonists increased the heart rate by 1.86 beats/min (bpm) (95% CI 0.85 to 2.87) versus placebo and 1.90 bpm (1.30 to 2.50) versus active control. This effect was more evident for liraglutide and exenatide long-acting release than for exenatide twice daily. GLP-1 agonists decreased systolic blood pressure by -1.79 mm Hg (-2.94 to -0.64) and -2.39 mm Hg (-3.35 to -1.42) compared to placebo and active control, respectively. Reduction in diastolic blood pressure failed to reach statistical significance (-0.54 mm Hg (-1.15 to 0.07) vs placebo and -0.50 mm Hg (-1.24 to 0.24) vs active control). Body weight decreased by -3.31 kg (-4.05 to -2.57) compared to active control, but by only -1.22 kg (-1.51 to -0.93) compared to placebo.

CONCLUSIONS

GLP-1 analogues are associated with a small increase in heart rate and modest reductions in body weight and blood pressure. Mechanisms underlying the rise in heart rate require further investigation.

Effects of liraglutide, a human glucagon-like peptide-1 analogue, on body weight, body fat area and body fat-related markers in patients with type 2 diabetes mellitus

OBJECTIVE

To evaluate the effects of six-month liraglutide treatment on body weight, visceral and subcutaneous fat and related markers in Japanese type 2 diabetic patients.

METHODS

A total of 59 patients with type 2 diabetes were treated with liraglutide (0.3 mg/day for ≥1 week and then 0.6 mg/day for ≥1 week, gradually increasing the dose to 0.9 mg/day) for six months. Changes in body weight, body mass index (BMI), HbA1c, the fasting blood glucose level, visceral and subcutaneous fat areas, hepatic and renal CT values and the associated markers proinsulin, adiponectin and pentraxin (PTX) 3 were measured.

RESULTS

The study included one treatment-naïve patient, 10 patients who were switched from oral antidiabetic drugs and 35 patients who were switched from insulin therapy. At six months after treatment, the preprandial blood glucose levels were higher (148.8±40.5 mg/dL) than the baseline values (130.8±36.7, p<0.05); however, body weight, BMI and abdominal circumference were lower, and the liver/kidney CT ratio improved significantly from 1.64±0.44 at baseline to 1.78±0.42. An analysis of the patients who were not pretreated with insulin resistance ameliorators showed that six months of liraglutide treatment significantly decreased the subcutaneous but not visceral fat areas, significantly decreased the serum adiponectin levels and significantly increased the serum PTX3 levels.

CONCLUSION

In addition to its glucose-lowering effects, liraglutide exhibits weight loss promotion actions, reducing subcutaneous fat areas in particular. The weight and total fat area reduction properties of liraglutide are likely to be beneficial when this medication is used in combination with other oral antidiabetic drugs and insulin.

Exenatide improves endothelial function assessed by flow mediated dilation technique in subjects with type 2 diabetes: results from an observational research

The GLP-1 receptor agonist exenatide has been approved for adjunctive treatment of type 2 diabetes. Continuous GLP-1 infusion improves endothelial function in vivo; no evidence about a beneficial effect of exenatide on vascular function has been published. The aim of our observational study was to evaluate whether exenatide would improve brachial artery function evaluated by the flow mediated dilation (FMD) technique, compared with glimepiride, in subjects with type 2 diabetes. FMD time course was assessed by ultrasound, after 5 min forearm ischaemia, at baseline and after 16-week treatment. At the end of the study FMD was significantly higher in subjects who assumed exenatide compared with glimepiride (9.1 ± 3.6 vs. 5.6 ± 1.0, p = 0.01). Even if limited by the small number of studied subjects, who were not matched in the two treatment groups, this research study represents the first FMD evidence suggesting that chronic administration of exenatide improves arterial dilation.

Exenatide extended-release; clinical trials, patient preference, and economic considerations

Type 2 diabetes remains an escalating problem worldwide, despite a range of treatments being available. The revelation that insulin secretion is under the control of a gut hormone, glucagon-like peptide 1, has led to a new paradigm in the management of type 2 diabetes, ie, use of medicines that directly stimulate or prolong the actions of endogenous glucagon-like peptide 1 at its receptors. Exenatide is an agonist at the glucagon-like peptide 1 receptor, and was initially developed as a subcutaneous medication twice daily (ExBID). Clinical trials with ExBID established a role for exenatide in the treatment of type 2 diabetes. Subsequently, exenatide once weekly (ExQW) was shown to have advantages over ExBID, and there is now more emphasis on the development of ExQW. ExQW alone reduces glycosylated hemoglobin (HbA(1c)) and body weight, and is well tolerated. ExQW has been compared with sitagliptin, pioglitazone, and metformin, and been shown to have a greater ability to reduce HbA(1c) than these other medicines. The only preparation of insulin with which ExQW has been compared is insulin glargine, and ExQW had some favorable properties in this comparison, notably causing weight loss compared with the weight gain on insulin glargine. ExQW has been compared with another glucagon-like peptide 1 receptor agonist, liraglutide, and was noninferior to liraglutide in reducing HbA(1c). The small amount of evidence available shows that subjects with type 2 diabetes prefer ExQW to ExBID, and that adherence is high in the clinical trial setting. Health care and economic modeling suggests that ExQW will reduce diabetic complications and be cost-effective, compared with other medications, in long-term use. Little is known about whether subjects with type 2 diabetes prefer ExQW to other medicines, and whether adherence is good with ExQW in practice. These important topics require further study.

Exenatide plus metformin compared with metformin alone on β-cell function in patients with Type 2 diabetes

AIM

To quantify how much exenatide added to metformin improves β-cell function, and to evaluate the impact on glycaemic control, insulin resistance and inflammation compared with metformin alone.

METHODS

A total of 174 patients with Type 2 diabetes with poor glycaemic control were instructed to take metformin for 8 ± 2 months, then they were randomly assigned to exenatide (5 μg twice a day for the first 4 weeks and forced titration to 10 μg twice a day thereafter) or placebo for 12 months. At 12 months we evaluated anthropometric measurements, glycaemic control, insulin resistance and β-cell function variables, glucagon, adiponectin, high sensitivity-C reactive protein and tumour necrosis factor-α. Before and after 12 months, patients underwent a combined euglycaemic hyperinsulinaemic and hyperglycaemic clamp, with subsequent arginine stimulation.

RESULTS

Exenatide + metformin gave a greater decrease in body weight, glycaemic control, fasting plasma proinsulin and insulin and their ratio, homeostasis model assessment for insulin resistance (HOMA-IR), and glucagon values and a greater increase in C-peptide levels, homeostasis model assessment β-cell function index (HOMA-β) and adiponectin compared with placebo + metformin. Exenatide + metformin decreased waist and hip circumference, and reduced concentrations of high sensitivity-C reactive protein and tumour necrosis factor-α. Exenatide + metformin gave a greater increase in M value (+34%), and disposition index (+55%) compared with placebo + metformin; first (+21%) and second phase (+34%) C-peptide response to glucose and C-peptide response to arginine (+25%) were also improved by exenatide + metformin treatment, but not by placebo + metformin.

CONCLUSION

Exenatide is effective not only on glycaemic control, but also in protecting β-cells and in reducing inflammation.

Metformin and its clinical use: new insights for an old drug in clinical practice

Metformin is generally recommended as first-line treatment in type 2 diabetes, especially in overweight patients, but in recent years new indications for its use have emerged. Metformin has been found to be safe and efficacious both as monotherapy and in combination with all oral antidiabetic agents and insulins. If metformin use during pregnancy and the lactation period is supported by few data, it could be indicated for women with polycystic ovary syndrome, since it could diminish circulating androgens and insulin resistance, thus ameliorating the ovulation rate. Metformin seems to reduce cancer risk, which appears to be increased in diabetics, and is a promising agent for oncoprevention and chemotherapy combinations. Moreover, metformin could find a place in the treatment of non-alcoholic fatty liver disease. Lactic acidosis could be decreased by avoiding metformin use in patients with hypovolemia, sepsis, renal impairment, hypoxic respiratory diseases and heart failure, in the preoperative period and before intravenous injection of contrast media.

Sitagliptin added to previously taken antidiabetic agents on insulin resistance and lipid profile: a 2-year study evaluation

The aim of this study was to evaluate whether the positive effects of sitagliptin on glycemic control and insulin resistance were maintained also after 2 years of therapy and whether sitagliptin could be effective also in improving lipid profile. In this randomized, double-blind, placebo-controlled trial, 205 patients with type 2 diabetes in therapy with different antidiabetic drugs were randomized to add sitagliptin 100 mg once a day or placebo to their current therapy. We evaluated at the baseline and after 6, 12, 18, and 24 months the following parameters: body mass index, glycated hemoglobin (HbA1c ), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), fasting plasma insulin (FPI), homeostasis model assessment insulin resistance index (HOMA-IR), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (Tg). Sitagliptin, added to previously taken antidiabetic agents, proved to be effective in improving glycemic profile, reducing HbA1c by -17.5%, FPG by -12.7%, PPG by -20.5%. Regarding insulin resistance, sitagliptin decreased FPI by -8.3% and HOMA-IR by -20.0%, confirming that what have been already reported in short-term studies can be applied also after 2 years of treatment. Sitagliptin also reduced body weight by -4.3%. Our study also showed the positive effect of sitagliptin on lipid profile; in particular, sitagliptin decreased TC by -13.3%, LDL-C by -20.4%, and Tg by -32.3%, and also increased HDL-C by + 13.6%. Sitagliptin proved to be effective on glycemic profile and insulin resistance even after 2 years of therapy and to be effective in improving body weight and lipid profile.