Glucagon-like peptide-1 receptor agonists and pancreatitis: a meta-analysis of randomized clinical trials

Adverse drug reactions associated with the use of liraglutide in patients with type 2 diabetes--focus on pancreatitis and pancreas cancer

INTRODUCTION

The glucagon-like peptide-1 (GLP-1) receptor agonist, liraglutide , is a widely used drug for the treatment of type 2 diabetes. Liraglutide is one of several incretin-based agents that have been suggested to be associated with pancreatitis and pancreas cancer. The suspicion accelerated after publication of an autopsy study claiming increased incidences of several pathological changes in pancreata from patients with diabetes treated with incretin-based drugs.

AREAS COVERED

The aim of the present review is to give an overview of the pharmacology of liraglutide and provide a review of adverse reactions associated with liraglutide with a focus on the risk of pancreatitis and pancreas cancer.

EXPERT OPINION

When comprehensively reviewing the available literature, no clear and significant associations between liraglutide and pancreatitis and/or pancreas cancer seem evident. However, a recently published analysis suggests a trend toward a slightly elevated risk of pancreatitis with GLP-1 receptor agonists (including liraglutide), which may become statistical significant as more data become available. Well-established side effects are of gastrointestinal origin, typical mild-to-moderate and of transient character. The risk of hypoglycemia associated with liraglutide treatment is low.

Defining the role of GLP-1 receptor agonists for individualized treatment of Type 2 diabetes

With the advent of dipeptidyl peptidase (DPP)-4 inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) over the past decade, incretin therapy has become established as an important treatment strategy for Type 2 diabetes mellitus (T2DM), with an efficacy and safety profile distinct from that of other anti-hyperglycemic agents. However, our understanding of the optimal clinical use of incretins remains incomplete. This review focuses on the use of GLP-1 RAs in the treatment of T2DM, with reference to the differing dominant mechanisms of action between short- and long-acting GLP-1 RAs and the clinical implications of this difference. The role of GLP-1 and the effects of GLP-1 RAs in various organs other than the pancreas will also be discussed.

Antihyperglycaemic therapies and cancer risk

AIMS

This review is aimed at highlighting the potential mitogenic/tumour growth-promoting or antimitogenic/tumour growth-inhibiting effects of the main antihyperglycaemic drug classes.

METHODS

We review and discuss the most current studies evaluating the association between antidiabetic medications used in clinical practice and malignancies as described so far.

RESULTS

Metformin seems to be the only antidiabetic drug to exert protective effects both on monotherapy and also when combined with other oral antidiabetic drugs or insulins in several site-specific cancers. In contrast, several other drug classes may increase cancer risk. Some reason for concern remains regarding sulphonylureas and also the incretin-based therapies regarding pancreas and thyroid cancers and the sodium glucose cotransporter-2 inhibitors as well as pioglitazone regarding bladder cancer. The majority of meta-analyses suggest that there is no evidence for a causal relationship between insulin glargine and elevated cancer risk, although the studies have been controversially discussed. For α-glucosidase inhibitors and glinides, neutral or only few data upon cancer risk exist.

CONCLUSION

Although the molecular mechanisms are not fully understood, a potential risk of mitogenicity and tumour growth promotion cannot be excluded in case of several antidiabetic drug classes. However, more large-scale, randomized, well-designed clinical studies with especially long follow-up time periods are needed to get reliable answers to these safety issues.

Indirect comparison of lixisenatide versus neutral protamine Hagedorn insulin as add-on to metformin and sulphonylurea in patients with type 2 diabetes mellitus

Objective: There is currently a lack of evidence from direct comparisons of treatment outcomes with lixisenatide versus neutral protamine Hagedorn (NPH)-insulin in type 2 diabetes mellitus (T2DM) patients with suboptimal glycaemic control with oral antidiabetic drugs (OADs). Hence, the current analysis indirectly compared available evidence on the risk of hypoglycaemia and weight change between lixisenatide and NPH-insulin based on randomized controlled trial (RCT) data with exenatide, insulin glargine and placebo as common references.

Methods: A systematic search of PubMed, Embase, the Cochrane database and clinical registries identified English- and German-language articles published from January 1980 to October 2012 reporting data from RCTs. Only publications of trials that reported outcomes from 24 to 30 weeks comparing glucagon-like peptide-1 receptor agonists or basal insulin versus another antidiabetic agent or placebo were included. Hypoglycaemia, patients at glycated haemoglobin (HbA_1c) target and discontinuations due to adverse events (AEs) were treated as binary variables, with risk ratios and odds ratios (ORs) calculated. HbA_1c and body weight were treated as continuous variables with difference in mean change from baseline (MD) calculated. Meta-analyses were performed with random effects models and indirect comparisons were performed according to Bucher’s method.

Results: Seven RCTs (n=3,301 patients) comparing the efficacy and safety of lixisenatide, exenatide, insulin glargine and NPH-insulin with different antidiabetic treatments in adult patients with T2DM were included in the final analysis. In the adjusted indirect comparison, there was a significant difference in symptomatic hypoglycaemia (OR = 0.38; 95% CI = [0.17, 0.85]) and in confirmed hypoglycaemia (OR = 0.46; 95% CI = [0.22, 0.96]) favouring lixisenatide over NPH-insulin and comparable changes in HbA_1c from baseline (MD = 0.07%; 95% CI = [–0.26%, 0.41%]). In contrast to NPH-insulin, there was a significant reduction in body weight with lixisenatide (MD = –3.62 kg; 95% CI = [–5.86 kg, –1.38 kg]) at study completion. The number of discontinuations due to AEs numerically favoured NPH-insulin over lixisenatide (OR = 2.64; 95% CI = [0.25, 27.96]), with a broad confidence interval.

Conclusions: Lixisenatide treatment was associated with a lower risk of hypoglycaemia and a greater weight loss compared with NPH-insulin. Glycaemic control with lixisenatide treatment was comparable with NPH-insulin. These data suggest that lixisenatide is a beneficial treatment option for T2DM patients with inadequate glycaemic control on OADs, and is associated with reduced risk of hypoglycaemia and weight gain.

Basal insulin combined incretin mimetic therapy with glucagon-like protein 1 receptor agonists as an upcoming option in the treatment of type 2 diabetes: a practical guide to decision making

The combination of basal insulin and glucagon-like protein 1 receptor agonists (GLP-1 RAs) is a new intriguing therapeutic option for patients with type 2 diabetes. In our daily practice we abbreviate this therapeutic concept with the term BIT (basal insulin combined incretin mimetic therapy) in a certain analogy to BOT (basal insulin supported oral therapy). In most cases BIT is indeed an extension of BOT, if fasting, prandial or postprandial blood glucose values have not reached the target range. In our paper we discuss special features of combinations of short- or prandial-acting and long- or continuous-acting GLP-1 RAs like exenatide, lixisenatide and liraglutide with basal insulin in relation to different glycemic targets. Overall it seems appropriate to use a short-acting GLP-1 RA if, after the near normalization of fasting blood glucose with BOT, the prandial or postprandial values are elevated. A long-acting GLP-1 RA might well be given, if fasting blood glucose values are the problem. Based on pathophysiological findings, recent clinical studies and our experience with BIT and BOT as well as BOTplus we developed chart-supported algorithms for decision making, including features and conditions of patients. The development of these practical tools was guided by the need for a more individualized antidiabetic therapy and the availability of the new BIT principle.

Therapies for inter-relating diabetes and obesity - GLP-1 and obesity

INTRODUCTION

The dramatic rise in the prevalence of obesity and type 2 diabetes mellitus (T2DM) is associated with increased mortality, morbidity as well as public health care expenses worldwide. The need for effective and long-lasting pharmaceutical treatment is obvious. The record of anti-obesity drugs has been poor so far and the only efficient treatment today is bariatric surgery. Research has indicated that appetite inhibiting hormones from the gut may have a therapeutic potential in obesity. The gut incretin hormone, glucagon-like peptide-1 (GLP-1), appears to be involved in both peripheral and central pathways mediating satiety. Clinical trials have shown that two GLP-1 receptor agonists exenatide and liraglutide have a weight-lowering potential in non-diabetic obese individuals. Furthermore, they may also hold a potential in preventing diabetes as compared to other weight loss agents.

AREAS COVERED

The purpose of this review is to cover the background for the GLP-1-based therapies and their potential in obesity and pre-diabetes. Up-to-date literature on incretin-based therapies will be summarized with a special mention of their weight-lowering properties. The literature updated to August 2014 from PubMed was identified using the combinations: GLP-1, GLP-1 receptor agonists, incretins, obesity and pre-diabetes.

EXPERT OPINION

The incretin impairment, which seems to exist in both obesity and diabetes, may link these two pathologies and underlines the potential of GLP-1-based therapies in the prevention and treatment of these diseases.

Risk of pancreatitis in patients treated with incretin-based therapies

AIMS/HYPOTHESIS

Incretin-based therapies have been suggested to increase the risk of pancreatitis, but the results of the available studies are controversial. Because results from prospective trials are limited by low statistical power, and because retrospective studies are often subject to bias, a pooled analysis of phase III clinical trials and two endpoint trials was performed.

METHODS

Event numbers for acute pancreatitis and patient-years of exposure (PYOs) were obtained from representatives of the pharmaceutical companies, or by literature research. Data were pooled for glucagon-like peptide 1 (GLP-1) receptor agonists and dipeptidyl-peptidase 4 (DPP-4) inhibitors in comparison with their respective controls and expressed as exposure-adjusted incidence rates.

RESULTS

A total of 38 cases of pancreatitis were reported in clinical trials with GLP-1 receptor agonists, comprising 17,775 PYOs. With the comparator treatment, nine events occurred in 5,863 PYOs. The pooled event rates were 2.1 and 1.5 per 1,000 PYOs, respectively, resulting in an OR of 1.39 (95% CI 0.67, 2.88). With DPP-4 inhibitors, 57 events were reported in 45,132 PYOs compared with 46 events in 38,883 PYOs with the comparator treatment. Pooled event rates were 1.3 and 1.2 per 1,000 PYOs, respectively, resulting in an OR of 1.07 (CI 0.72, 1.58).

CONCLUSIONS/INTERPRETATION

This analysis suggests a trend towards a slightly elevated risk of pancreatitis with GLP-1 receptor agonists. With DPP-4 inhibitors, no consistent trend was found. However, the incidence numbers of cases of pancreatitis were still very small, and the statistical power was limited. Future endpoint trials may help to provide a better estimate of the true risk of pancreatitis with incretin-based therapies.

Incretin based drugs and risk of acute pancreatitis in patients with type 2 diabetes: cohort study

OBJECTIVES

To determine whether the use of incretin based drugs, compared with sulfonylureas, is associated with an increased risk of acute pancreatitis.

DESIGN

Population based cohort study.

SETTING

680 general practices in the United Kingdom contributing to the Clinical Practice Research Datalink.

PARTICIPANTS

From 1 January 2007 to 31 March 2012, 20 748 new users of incretin based drugs were compared with 51 712 users of sulfonylureas and followed up until 31 March 2013.

MAIN OUTCOME MEASURES

Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals for acute pancreatitis in users of incretin based drugs compared with users of sulfonylureas. Models were adjusted for tenths of high dimensional propensity score (hdPS).

RESULTS

The crude incidence rate for acute pancreatitis was 1.45 per 1000 patients per year (95% confidence interval 0.99 to 2.11) for incretin based drug users and 1.47 (1.23 to 1.76) for sulfonylurea users. The rate of acute pancreatitis associated with the use of incretin based drugs was not increased (hdPS adjusted hazard ratio: 1.00, 95% confidence interval 0.59 to 1.70) relative to sulfonylurea use.

CONCLUSIONS

Compared with use of sulfonylureas, the use of incretin based drugs is not associated with an increased risk of acute pancreatitis. While this study is reassuring, it does not preclude a modest increased risk, and thus additional studies are needed to confirm these findings.

Monotherapy with the once weekly GLP-1 receptor agonist dulaglutide for 12 weeks in Japanese patients with type 2 diabetes: dose-dependent effects on glycaemic control in a randomised, double-blind, placebo-controlled study

The aim of this study was to evaluate the dose-dependent effect of dulaglutide, a glucagon-like peptide-1 receptor agonist, on glycaemic control in Japanese patients with type 2 diabetes mellitus who were treated with diet/exercise or oral antidiabetic drug monotherapy. In this randomised, double-blind, placebo-controlled, parallel-group, 12-week study, patients received once weekly subcutaneous dulaglutide doses of 0.25, 0.5, or 0.75 mg (DU 0.25, DU 0.5, and DU 0.75, respectively) or placebo (n=36, 37, 35, and 37, respectively). The primary measure was change from baseline in glycated haemoglobin (HbA1c; %) at 12 weeks. Continuous variables were analysed using a mixed-effects model for repeated measures. Significant dose-dependent reductions in HbA1c were observed (least squares mean difference versus placebo [95% confidence interval]): DU 0.25=-0.72% (-0.95, -0.48), DU 0.5=-0.97% (-1.20, -0.73), and DU 0.75=-1.17% (-1.41, -0.93); p<0.001. Significant improvements in plasma glucose (PG), both fasting and average 7-point self-monitored blood glucose, were also observed with dulaglutide versus placebo (p<0.001). Dulaglutide was well-tolerated. Gastrointestinal adverse events (AEs) were more common in dulaglutide-treated patients, with nausea the most frequent (8 [5.5%]). Few dulaglutide-treated patients discontinued due to AEs (4 [3.7%]), and no serious AEs related to study medication occurred. Three patients (DU 0.5=1 and DU 0.75=2) reported asymptomatic hypoglycaemia (PG ≤70 mg/dL). The observed dose-dependent reduction in HbA1c and acceptable safety profile support further clinical development of dulaglutide for treatment of type 2 diabetes mellitus in Japan.