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Background

To examine the effects of liraglutide, a glucagon-like peptide-1 (GLP-1) analogue, on visceral fat adiposity, appetite, food preference, and biomarkers of cardiovascular system in Japanese patients with type 2 diabetes.

Methods

The study subjects were 20 inpatients with type 2 diabetes treated with liraglutide [age; 61.2 ± 14.0 years, duration of diabetes; 16.9 ± 6.6 years, glycated hemoglobin (HbA1c); 9.1 ± 1.2%, body mass index (BMI); 28.3 ± 5.2 kg/m2, mean ± SD]. After improvement in glycemic control by insulin or oral glucose-lowering agents, patients were switched to liraglutide. We assessed the estimated visceral fat area (eVFA) by abdominal bioelectrical impedance analysis, glycemic control by the 75-g oral glucose tolerance test (OGTT) and eating behavior by the Japan Society for the Study of Obesity questionnaire.

Results

Treatment with liraglutide (dose range: 0.3 to 0.9 mg/day) for 20.0 ± 6.4 days significantly reduced waist circumference, waist/hip ratio, eVFA. It also significantly improved the scores of eating behavior, food preference and the urge for fat intake and tended to reduce scores for sense of hunger. Liraglutide increased serum C-peptide immunoreactivity and disposition index.

Conclusions

Short-term treatment with liraglutide improved visceral fat adiposity, appetite, food preference and the urge for fat intake in obese Japanese patients with type 2 diabetes.

The authors discuss the strategy of use of incretin hormones in type 2 diabetes treatment in the context of cardiovascular complications. The results of the phase III study on human GLP-1 (Glucagon-like peptide-1) analogue-liraglutide have been presented under common acronym LEAD (Liraglutide-Effect and Action In Diabetes). The liraglutide therapy improved glycemic control with low hypoglycemia risk and decreased glycated hemoglobin by an average 1,13%. Decreases in systolic pressure and significant body weight loss were observed. Not only did the index describing beta cells function HOMA-B improve but also did the ratio of insulin to proinsulin. Summing up, incretin hormones beneficially influence blood glucose level, moreover, their use decreases blood pressure and body weight which might indicate their positive influence on cardiovascular system in diabetic patients.

Liraglutide is a glucagon-like peptide-1 analog with pharmacokinetic properties suitable for once-daily administration approved by the Food and Drug Administration for the treatment of patients with type 2 diabetes. Clinical trial data from large, controlled studies demonstrate the safety and efficacy of liraglutide in terms of hemoglobin A1c (HbA1c) reduction, reductions in body weight, and the drug’s low risk for hypoglycemic events when used as monotherapy. Liraglutide has been studied as monotherapy and in combination with metformin, glimepiride, and rosiglitazone for the treatment of type 2 diabetes. Additionally, comparative data with insulin glargine and exenatide therapy are available from Phase III trials. Once-daily administration may provide a therapeutic advantage for liraglutide over twice-daily exenatide, with similar improvements in HbA1c and body weight observed when liraglutide was compared with exenatide. The glucose-dependent mechanism of insulin release with incretin analog therapy holds potential clinical significance in the management of postprandial hyperglycemic excursions, with minimal risk of hypoglycemia when used with non-secretagogue medications. Data to date on patient-reported outcomes with liraglutide treatment are encouraging. The most common adverse events associated with liraglutide therapy are dose-dependent nausea, vomiting, and diarrhea. Diligent postmarketing surveillance to elucidate the risk of pancreatitis and medullary thyroid carcinoma in a heterogeneous population are likely warranted.

OBJECTIVE

The efficacy of liraglutide, a human glucagon-like peptide-1 (GLP-1) analog, to prevent or delay diabetes in UCD-T2DM rats, a model of polygenic obese type 2 diabetes, was investigated.

RESEARCH DESIGN AND METHODS

At 2 months of age, male rats were divided into three groups: control, food-restricted, and liraglutide. Animals received liraglutide (0.2 mg/kg s.c.) or vehicle injections twice daily. Restricted rats were food restricted to equalize body weights to liraglutide-treated rats. Half of the animals were followed until diabetes onset, whereas the other half of the animals were killed at 6.5 months of age for tissue collection.

RESULTS

Before diabetes onset energy intake, body weight, adiposity, and liver triglyceride content were higher in control animals compared with restricted and liraglutide-treated rats. Energy-restricted animals had lower food intake than liraglutide-treated animals to maintain the same body weights, suggesting that liraglutide increases energy expenditure. Liraglutide treatment delayed diabetes onset by 4.1 ± 0.8 months compared with control (P < 0.0001) and by 1.3 ± 0.8 months compared with restricted animals (P < 0.05). Up to 6 months of age, energy restriction and liraglutide treatment lowered fasting plasma glucose and A1C concentrations compared with control animals. In contrast, liraglutide-treated animals exhibited lower fasting plasma insulin, glucagon, and triglycerides compared with both control and restricted animals. Furthermore, energy-restricted and liraglutide-treated animals exhibited more normal islet morphology.

CONCLUSIONS

Liraglutide treatment delays the development of diabetes in UCD-T2DM rats by reducing energy intake and body weight, and by improving insulin sensitivity, improving lipid profiles, and maintaining islet morphology.

Background. Liraglutide leading to improve not only glycaemic control but also liver inflammation in non-alcoholic fatty liver disease (NAFLD) patients. Aims. The aim of this study is to elucidate the effectiveness of liraglutide in NAFLD patients with type 2 diabetes mellitus (T2DM) compared to sitagliptin and pioglitazone. Methods. We retrospectively enrolled 82 Japanese NAFLD patients with T2DM and divided into three groups (liraglutide: N = 26, sitagliptin; N = 36, pioglitazone; N = 20). We compared the baseline characteristics, changes of laboratory data and body weight. Results. At the end of follow-up, ALT, fast blood glucose, and HbA1c level significantly improved among the three groups. AST to platelet ratio significantly decreased in liraglutide group and pioglitazone group. The body weight significantly decreased in liraglutide group (81.8 kg to 78.0 kg, P < 0.01). On the other hands, the body weight significantly increased in pioglitazone group and did not change in sitagliptin group. Multivariate regression analysis indicated that administration of liraglutide as an independent factor of body weight reduction for more than 5% (OR 9.04; 95% CI 1.12–73.1, P = 0.04). Conclusions. Administration of liraglutide improved T2DM but also improvement of liver inflammation, alteration of liver fibrosis, and reduction of body weight.

Objective

To assess the efficacy and safety of adding liraglutide to established insulin therapy in poorly controlled Chinese subjects with type 2 diabetes and abdominal obesity compared with increasing insulin dose.

Methods

A 12-week, randomized, parallel-group study was carried out. A total of 84 patients completed the trial who had been randomly assigned to either the liraglutide-added group or the insulin-increasing group while continuing current insulin based treatment. Insulin dose was reduced by 0-30% upon the initiation of liraglutide. Insulin doses were subsequently adjusted to optimized glycemic control. Glycosylated hemoglobin (HbA1c) values, blood glucose, total daily insulin dose, body weight, waist circumference, and the number of hypoglycemic events and adverse events were evaluated.

Results

At the end of study, the mean reduction in HbA1c between the liraglutide-added group and the insulin-increasing group was not significantly different (1.9% vs. 1.77%, p>0.05). However, the percentage of subjects reaching the composite endpoint of HbA1c ≤ 7.0% with no weight gain and no hypoglycemia, was significantly higher in the liraglutide-added group than in the insulin-increasing group (67% vs. 19%, p<0.001). Add-on liraglutide treatment significantly reduced mean body weight (5.62 kg, p<0.01), waist circumference (5.70 cm, p<0.01), body mass index (BMI) (1.93 kg/m2, p<0.01) and daily total insulin dose (dropped by 66%) during 12-week treatment period, while all of these significantly increased with insulin increasing treatment. Add-on liraglutide treated patients had lower rate of hypoglycemic events and greater insulin and oral antidiabetic drugs discontinuation. Gastrointestinal disorders were the most common adverse events in the liraglutide added treatment, but were transient.

Conclusions

Addition of liraglutide to abdominally obese, insulin-treated patients led to improvement in glycemic control similar to that achieved by increasing insulin dosage, but with a lower daily dose of insulin and fewer hypoglycemic events. Adding liraglutide to insulin also induced a significant reduction in body weight and waist circumference. Liraglutide combined with insulin may be the best treatment option for poorly controlled type 2 diabetes and abdominal obesity.

Video abstract

Video

Background

Liraglutide is an analog of human glucagon-like peptide-1 (GLP-1) and acts as a GLP-1 receptor agonist. Liraglutide is presently used in the treatment of selected patients with type 2 diabetes mellitus (T2DM).

Objective

To assess efficacy and safety of liraglutide in, overweight and obese Indian patients with T2DM.

Methods

A single center, prospective, open-labeled, single-arm, observational study for 24 weeks in a real-world setting. Fourteen overweight and obese patients with T2DM who were clinically suitable for liraglutide therapy received liraglutide injections. The starting dose of liraglutide (Victoza) injection was 0.6 mg/day for 3 days followed by 1.2 mg for next 10 days and finally 1.8 mg/day for 22 weeks. Patients were evaluated at baseline and after 12 and 24 weeks of therapy. Adverse events (AE) noted during course of therapy were recorded. A repeated measure analysis of variance was performed to assess statistical significance.

Results

Fourteen patients were studied for 24 weeks. After 24 weeks of liraglutide therapy, mean fasting and postprandial plasma glucose decreased by 48.5 mg/dL and 66.71 mg/dL, respectively (P = 0.002 and P = 0004 over 24 weeks, respectively). A mean reduction of 2.26% of glycosylated hemoglobin was noted (P < 0.001 over 24 weeks). Mean decrease in body weight of 8.65 kg and mean decrease in body mass index of 3.26 kg/m2 was noted (P < 0.001 over 24 weeks for each parameter). Systolic blood pressure was reduced by 15.15 mm of Hg (P = 0.004). Significant improvement in total cholesterol, low-density lipoprotein, triglycerides, and serum creatinine was noted. Nine patients reported AEs. The AEs noticed were nausea (n = 6), feeling of satiety (n = 3), and vomiting (n = 1). No serious AE or hypoglycemic episodes were observed.

Conclusion

Liraglutide once a day improved overall glycemic control and was well tolerated. Clinically significant reduction in body weight, systolic blood pressure and improvement in lipid profile were noticed with liraglutide therapy in addition to glycemic control.

Incretin-based therapies have been gaining much attention recently as a new class of therapeutics for type 2 diabetes worldwide. Among them, glucagon-like peptide-1 receptor agonist liraglutide has been rapidly increasing its global usage. Once daily injection of liraglutide significantly ameliorates glycemic control in patients with type 2 diabetes by enhancing insulin secretion and suppressing glucagon secretion glucose-dependently. Liraglutide delays gastric emptying and suppresses food intakes, both of which contribute to glucose lowering and weight reduction. Efficacy and safety of liraglutide in management of type 2 diabetes have been well documented in several key clinical trials such as series of phase 3 Liraglutide Effect and Action in Diabetes (LEAD) trials, and the liraglutide-versus-sitagliptin trial. Recent two trials dealing with monotherapy and sulfonylurea combination therapy on Japanese patients with type 2 diabetes furthermore indicate liraglutide’s effectiveness in non-obese diabetes. In this review, we summarize results from such clinical trials, and discuss efficacy and safety of liraglutide in management of type 2 diabetes in various countries, along with a pitfall of liraglutide usage in real clinical setting.

Liraglutide is a long-acting analog of GLP-1, being developed by Novo Nordisk and currently undergoing regulatory review for the treatment of type 2 diabetes. Upon injection, liraglutide binds non-covalently to albumin, giving it a pharmacokinetic profile suitable for once-daily administration. In clinical trials of up to 1 year duration, liraglutide has been demonstrated to have beneficial effects on islet cell function, leading to improvements in glycemic control. Both fasting and postprandial glucose concentrations are lowered, and are associated with lasting reductions in HbA1c levels. Liraglutide is effective as monotherapy and in combination therapy with oral antidiabetic drugs, and reduces HbA1c by up to ∼1.5% from baseline (8.2%–8.4%). Because of the glucose-dependency of its action, there is a low incidence of hypoglycemia. Liraglutide is associated with body weight loss, and reductions in systolic blood pressure have been observed throughout the clinical trials. The most common adverse events reported with liraglutide are gastrointestinal (nausea, vomiting and diarrhea). These tend to be most pronounced during the initial period of therapy and decline with time. Further clinical experience with liraglutide will reveal its long-term durability, safety and efficacy.

Aim

To compare the effects of combining liraglutide (0.6, 1.2 or 1.8 mg/day) or rosiglitazone 4 mg/day (all n ≥ 228) or placebo (n = 114) with glimepiride (2–4 mg/day) on glycaemic control, body weight and safety in Type 2 diabetes.

Methods

In total, 1041 adults (mean ± sd), age 56 ± 10 years, weight 82 ± 17 kg and glycated haemoglobin (HbA1c) 8.4 ± 1.0% at 116 sites in 21 countries were stratified based on previous oral glucose-lowering mono : combination therapies (30 : 70%) to participate in a five-arm, 26-week, double-dummy, randomized study.

Results

Liraglutide (1.2 or 1.8 mg) produced greater reductions in HbA1c from baseline, (−1.1%, baseline 8.5%) compared with placebo (+0.2%, P < 0.0001, baseline 8.4%) or rosiglitazone (−0.4%, P < 0.0001, baseline 8.4%) when added to glimepiride. Liraglutide 0.6 mg was less effective (−0.6%, baseline 8.4%). Fasting plasma glucose decreased by week 2, with a 1.6 mmol/l decrease from baseline at week 26 with liraglutide 1.2 mg (baseline 9.8 mmol/l) or 1.8 mg (baseline 9.7 mmol/l) compared with a 0.9 mmol/l increase (placebo, P < 0.0001, baseline 9.5 mmol/l) or 1.0 mmol/l decrease (rosiglitazone, P < 0.006, baseline 9.9 mmol/l). Decreases in postprandial plasma glucose from baseline were greater with liraglutide 1.2 or 1.8 mg [−2.5 to −2.7 mmol/l (baseline 12.9 mmol/l for both)] compared with placebo (−0.4 mmol/l, P < 0.0001, baseline 12.7 mmol/l) or rosiglitazone (−1.8 mmol/l, P < 0.05, baseline 13.0 mmol/l). Changes in body weight with liraglutide 1.8 mg (−0.2 kg, baseline 83.0 kg), 1.2 mg (+0.3 kg, baseline 80.0 kg) or placebo (−0.1 kg, baseline 81.9 kg) were less than with rosiglitazone (+2.1 kg, P < 0.0001, baseline 80.6 kg). Main adverse events for all treatments were minor hypoglycaemia (< 10%), nausea (< 11%), vomiting (< 5%) and diarrhoea (< 8%).

Conclusions

Liraglutide added to glimepiride was well tolerated and provided improved glycaemic control and favourable weight profile.

OBJECTIVE

Glucagon-like peptide-1 receptor (GLP-1R) agonists are used to treat type 2 diabetes, and transient GLP-1 administration improved cardiac function in humans after acute myocardial infarction (MI) and percutaneous revascularization. However, the consequences of GLP-1R activation before ischemic myocardial injury remain unclear.

RESEARCH DESIGN AND METHODS

We assessed the pathophysiology and outcome of coronary artery occlusion in normal and diabetic mice pretreated with the GLP-1R agonist liraglutide.

RESULTS

Male C57BL/6 mice were treated twice daily for 7 days with liraglutide or saline followed by induction of MI. Survival was significantly higher in liraglutide-treated mice. Liraglutide reduced cardiac rupture (12 of 60 versus 46 of 60; P = 0.0001) and infarct size (21 ± 2% versus 29 ± 3%, P = 0.02) and improved cardiac output (12.4 ± 0.6 versus 9.7 ± 0.6 ml/min; P = 0.002). Liraglutide also modulated the expression and activity of cardioprotective genes in the mouse heart, including Akt, GSK3β, PPARβ-δ, Nrf-2, and HO-1. The effects of liraglutide on survival were independent of weight loss. Moreover, liraglutide conferred cardioprotection and survival advantages over metformin, despite equivalent glycemic control, in diabetic mice with experimental MI. The cardioprotective effects of liraglutide remained detectable 4 days after cessation of therapy and may be partly direct, because liraglutide increased cyclic AMP formation and reduced the extent of caspase-3 activation in cardiomyocytes in a GLP-1R–dependent manner in vitro.

CONCLUSIONS

These findings demonstrate that GLP-1R activation engages prosurvival pathways in the normal and diabetic mouse heart, leading to improved outcomes and enhanced survival after MI in vivo.

Glucagon-Like Peptide-1 receptor agonists (GLP-1RAs), approved as glucose-lowering drugs for the treatment of type 2 diabetes, have also been shown to reduce body weight. An extensive Medline, Cochrane database, and Embase search for “exenatide,” “liraglutide,” “albiglutide,” “semaglutide,” and “lixisenatide” was performed, collecting all randomized clinical trials on humans up to December 15, 2011, with a duration of at least 24 weeks, comparing GLP-1 receptor agonists with either placebo or active drugs. Twenty two (7,859 patients) and 7 (2,416 patients) trials with available results on body weight at 6 and 12 months, respectively, were included. When compared with placebo, GLP-1RAs determine a reduction of BMI at 6 months of −1.0 [−1.3; −0.6] kg/m2. Considering the average BMI at baseline (32.4 kg/m2) these data means a weight reduction of about 3% at 6 months. This result could seem modest from a clinical standpoint; however, it could be affected by many factors contributing to an underestimation of the effect of GLP-1RA on body weight, such as non adequate doses, inclusion criteria, efficacy of GLP-1RA on reducing glycosuria, and association to non-pharmacological interventions not specifically aimed to weight reduction.

Clinical question

Which antidiabetic drugs provide optimal weight control in patients with type 2 diabetes?

Results

Metformin reduces weight gain, and may cause weight loss, when given alone or in combination with other drugs. Pioglitazone and rosiglitazone use is associated with weight gain. Use of the glucagon-like peptide-1 (GLP-1) analogs, liraglutide and exenatide, is associated with weight loss. Dipeptidyl peptidase-4 (DPP-4) inhibitors are considered weight-neutral. Results with insulin therapy are conflicting. Insulin detemir provides weight control along with glycemic control.

Implementation

Weight gain is considered an inevitable part of good glycemic control using conventional modalities of treatment such as sulfonylureas.1Use of metformin, weight-sparing insulin analogs such as insulin detemir, and liraglutide, should be encouraged as monotherapy, or in combination with other drugs.

The pathophysiology of type 2 diabetes has been attributed to the classic triad of decreased insulin secretion, increased insulin resistance, and elevated hepatic glucose production. Research has shown additional mechanisms, including incretin deficiency or resistance in the gastrointestinal tract. Liraglutide is a modified form of human glucagon-like peptide-1. Liraglutide was obtained by substitution of lysine 34 for arginine near the NH2 terminus, and by addition of a C16 fatty acid at the ɛ-amino group of lysine (at position 26) using a γ-glutamic acid spacer. Liraglutide has demonstrated glucose-dependent insulin secretion, improvements in β-cell function, deceleration of gastric emptying, and promotion of early satiety leading to weight loss. Liraglutide has the potential to acquire an important role, not only in the treatment of type 2 diabetes, but also in preservation of β-cell function, weight loss, and prevention of chronic diabetic complications.

Objective To determine whether treatment with agonists of glucagon-like peptide-1 receptor (GLP-1R) result in weight loss in overweight or obese patients with or without type 2 diabetes mellitus.

Design Systematic review with meta-analyses.

Data sources Electronic searches (Cochrane Library, Medline, Embase, and Web of Science) and manual searches (up to May 2011).

Review methods Randomised controlled trials of adult participants with a body mass index of 25 or higher; with or without type 2 diabetes mellitus; and who received exenatide twice daily, exenatide once weekly, or liraglutide once daily at clinically relevant doses for at least 20 weeks. Control interventions assessed were placebo, oral antidiabetic drugs, or insulin.

Data extraction Three authors independently extracted data. We used random effects models for the primary meta-analyses. We also did subgroup, sensitivity, regression, and sequential analyses to evaluate sources of intertrial heterogeneity, bias, and the robustness of results after adjusting for multiple testing and random errors.

Results 25 trials were included in the analysis. GLP-1R agonist groups achieved a greater weight loss than control groups (weighted mean difference −2.9 kg, 95% confidence interval –3.6 to –2.2; 21 trials, 6411 participants). We found evidence of intertrial heterogeneity, but no evidence of bias or small study effects in regression analyses. The results were confirmed in sequential analyses. We recorded weight loss in the GLP-1R agonist groups for patients without diabetes (–3.2 kg, –4.3 to –2.1; three trials) as well as patients with diabetes (–2.8 kg, –3.4 to –2.3; 18 trials). In the overall analysis, GLP-1R agonists had beneficial effects on systolic and diastolic blood pressure, plasma concentrations of cholesterol, and glycaemic control, but did not have a significant effect on plasma concentrations of liver enzymes. GLP-1R agonists were associated with nausea, diarrhoea, and vomiting, but not with hypoglycaemia.

Conclusions The present review provides evidence that treatment with GLP-1R agonists leads to weight loss in overweight or obese patients with or without type 2 diabetes mellitus.

OBJECTIVE

To determine the efficacy and safety of liraglutide (a glucagon-like peptide-1 receptor agonist) when added to metformin and rosiglitazone in type 2 diabetes.

RESEARCH DESIGN AND METHODS

This 26-week, double-blind, placebo-controlled, parallel-group trial randomized 533 subjects (1:1:1) to once-daily liraglutide (1.2 or 1.8 mg) or liraglutide placebo in combination with metformin (1 g twice daily) and rosiglitazone (4 mg twice daily). Subjects had type 2 diabetes, A1C 7–11% (previous oral antidiabetes drug [OAD] monotherapy ≥3 months) or 7–10% (previous OAD combination therapy ≥3 months), and BMI ≤45 kg/m2.

RESULTS

Mean A1C values decreased significantly more in the liraglutide groups versus placebo (mean ± SE −1.5 ± 0.1% for both 1.2 and 1.8 mg liraglutide and −0.5 ± 0.1% for placebo). Fasting plasma glucose decreased by 40, 44, and 8 mg/dl for 1.2 and 1.8 mg and placebo, respectively, and 90-min postprandial glucose decreased by 47, 49, and 14 mg/dl, respectively (P < 0.001 for all liraglutide groups vs. placebo). Dose-dependent weight loss occurred with 1.2 and 1.8 mg liraglutide (1.0 ± 0.3 and 2.0 ± 0.3 kg, respectively) (P < 0.0001) compared with weight gain with placebo (0.6 ± 0.3 kg). Systolic blood pressure decreased by 6.7, 5.6, and 1.1 mmHg with 1.2 and 1.8 mg liraglutide and placebo, respectively. Significant increases in C-peptide and homeostasis model assessment of β-cell function and significant decreases in the proinsulin-to-insulin ratio occurred with liraglutide versus placebo. Minor hypoglycemia occurred more frequently with liraglutide, but there was no major hypoglycemia. Gastrointestinal adverse events were more common with liraglutide, but most occurred early and were transient.

CONCLUSIONS

Liraglutide combined with metformin and a thiazolidinedione is a well-tolerated combination therapy for type 2 diabetes, providing significant improvements in glycemic control.

Aim

The aim of this study was to compare the efficacy and safety of once-daily human glucagon-like peptide-1 analogue liraglutide with dipeptidyl peptidase-4 inhibitor sitagliptin, each added to metformin, over 52 weeks in individuals with type 2 diabetes.

Methods

In an open-label, parallel-group trial, metformin-treated participants were randomised to liraglutide 1.2 mg/day (n= 225), liraglutide 1.8 mg/day (n= 221) or sitagliptin 100 mg/day (n= 219) for 26 weeks (main phase). Participants continued the same treatment in a 26-week extension.

Results

Liraglutide (1.2 or 1.8 mg) was superior to sitagliptin for reducing HbA1c from baseline (8.4–8.5%) to 52 weeks: −1.29% and −1.51% vs. −0.88% respectively. Estimated mean treatment differences between liraglutide and sitagliptin were as follows: −0.40% (95% confidence interval −0.59 to −0.22) for 1.2 mg and −0.63% (−0.81 to −0.44) for 1.8 mg (both p < 0.0001). Weight loss was greater with liraglutide 1.2 mg (−2.78 kg) and 1.8 mg (−3.68 kg) than sitagliptin (−1.16 kg) (both p < 0.0001). Diabetes Treatment Satisfaction Questionnaire scores increased significantly more with liraglutide 1.8 mg than with sitagliptin (p = 0.03). Proportions of participants reporting adverse events were generally comparable; minor hypoglycaemia was 8.1%, 8.3% and 6.4% for liraglutide 1.2 mg, 1.8 mg and sitagliptin respectively. Gastrointestinal side effects, mainly nausea, initially occurred more frequently with liraglutide, but declined after several weeks.

Conclusion

Liraglutide provides greater sustained glycaemic control and body weight reduction over 52 weeks. Treatment satisfaction was significantly greater with 1.8 mg liraglutide, similar to 26-week results. The safety profiles of liraglutide and sitagliptin are consistent with previous reports.

In people with type 2 diabetes mellitus (T2DM), the incretin effect is reduced, but the recent advent of dipeptidyl peptidase-4 inhibitors and glucagon-like peptide (GLP)-1 agonists/analogues has enabled restoration of at least some of the function of the incretin system, with accompanying improvements in glycaemic control. Two GLP-1 receptor agonists/analogues are currently approved for the treatment of T2DM—exenatide (Byetta®, Eli Lilly & Co., Indianapolis, IN, US) and liraglutide (Victoza®, Novo Nordisk, Bagsvaerd, Denmark); a once-weekly formulation of exenatide (Bydureon®, Eli Lilly & Co.) has also been approved by the European Medicines Agency. The National Institute for Health and Clinical Excellence (NICE) has recently published guidance on the use of liraglutide in T2DM, based on evidence from the Liraglutide Effect and Action in Diabetes (LEAD) Phase III trial programme, which compared liraglutide with existing glucose-lowering therapies, such as exenatide and insulin glargine. The LEAD programme reported HbA1c reductions from 0.8 to 1.5% with liraglutide (1.2 and 1.8 mg), accompanied by low rates of hypoglycaemia and some weight loss; side effects were primarily gastrointestinal in nature (e.g. nausea and diarrhoea). Based on the findings of the LEAD studies and the NICE recommendation, liraglutide now represents an important therapy widely available in the UK for certain patient groups, including those with a body mass index (BMI) ≥35.0 kg/m2, and patients with a BMI <35 kg/m2 who are considered unsuitable for insulin and are failing to meet targets for glycaemic control with oral agents. NICE guidelines still suggest that most patients without considerable obesity (BMI <35 kg/m2) are probably best managed using insulin therapy. Evidence also suggests a future role for GLP-1 mimetics in combination with basal insulin.

Aim: As weight gain and hypoglycaemia associated with glimepiride therapy can negatively impact weight perceptions, psychological well-being and overall quality of life in type 2 diabetes, we investigated whether liraglutide treatment could improve these factors.

Methods: Seven hundred and thirty-two patients with type 2 diabetes completed a 77-item questionnaire during a randomized, 52-week, double-blind study with liraglutide 1.2 mg (n = 245) or 1.8 mg (n = 242) compared with glimepiride 8 mg (n = 245).

Results: Mean (SE) decreases in glycated haemoglobin levels were greater with liraglutide 1.2 mg [−0.84 (0.08)%] and 1.8 mg [−1.14 (0.08)%] than glimepiride [−0.51 (0.08)%; p = 0.0014 and p < 0.0001, respectively]. Patients gained weight on glimepiride [mean (SE), 1.12 (0.27) kg] but lost weight on liraglutide [1.2 mg: −2.05 (0.28) kg; 1.8 mg: −2.45 (0.28) kg; both p < 0.0001]. Patient weight assessment was more favourable with liraglutide 1.8 mg [mean (SE) score: 40.0 (2.0)] than glimepiride [48.7 (2.0); p = 0.002], and liraglutide 1.8 mg patients were 52% less likely to feel overweight [odds ratio (OR) 0.48; 95% confidence interval (CI): 0.331–0.696]. Mean (SE) weight concerns were less with liraglutide [1.2 mg: 30.0 (1.2); 1.8 mg: 32.8 (1.2)] than glimepiride [38.8 (1.2); p < 0.0001 and p < 0.001, respectively], with liraglutide groups 45% less likely to report weight concern (OR 0.55, 95% CI: 0.41–0.73). Mean (SE) mental and emotional health and general perceived health improved more with liraglutide 1.8 mg [476.1 (2.8) and 444.2 (3.2), respectively] than glimepiride [466.3 (2.8) and 434.5 (3.2), respectively; p = 0.012 and p = 0.033, respectively].

Conclusions: Improved glycaemic control and decreased weight with liraglutide 1.8 mg vs. glimepiride can improve psychological and emotional well-being and health perceptions by reducing anxiety and worry associated with weight gain.

The prevalence of obesity has increased dramatically in recent decades, both in the US and worldwide. Pharmacotherapy can augment the weight-reducing effects of lifestyle modification and can facilitate long-term weight maintenance. However, there is a paucity of pharmacologic agents approved for the treatment of obesity, and the use of existing weight loss medications is frequently limited by contraindications, drug interactions, adverse effects, limited coverage by third-party payers, and cost. In recent years, there has been an increased understanding and appreciation of the role of gastrointestinal hormones in the control of body weight. One such hormone, GLP-1, also plays an important role in glucose homeostasis. GLP-1 receptor agonists, such as exenatide and liraglutide, have been developed and are already approved for the treatment of type 2 diabetes. There has also been interest in the use of GLP-1 receptor agonists for the treatment of obesity in nondiabetic patients. This review explores the potential utility and limitations of exenatide and liraglutide as therapeutic agents for obesity.

Aims: Most treatments for type 2 diabetes fail over time, necessitating combination therapy. We investigated the safety, tolerability and efficacy of liraglutide monotherapy compared with glimepiride monotherapy over 2 years.

Methods: Participants were randomized to receive once-daily liraglutide 1.2 mg, liraglutide 1.8 mg or glimepiride 8 mg. Participants completing the 1-year randomized, double-blind, double-dummy period could continue open-label treatment for an additional year. Safety data were evaluated for the full population exposed to treatment, and efficacy data were evaluated for the full intention-to-treat (ITT) and 2-year completer populations. Outcome measures included change in glycosylated haemoglobin (HbA1c), fasting plasma glucose (FPG), body weight and frequency of nausea and hypoglycaemia.

Results: For patients completing 2 years of therapy, HbA1c reductions were −0.6% with glimepiride versus −0.9% with liraglutide 1.2 mg (difference: −0.37, 95% CI: −0.71 to −0.02; p = 0.0376) and −1.1% with liraglutide 1.8 mg (difference: −0.55, 95% CI: −0.88 to −0.21; p = 0.0016). In the ITT population, HbA1c reductions were −0.3% with glimepiride versus −0.6% with liraglutide 1.2 mg (difference: −0.31, 95% CI: −0.54 to −0.08; p = 0.0076) and −0.9% with liraglutide 1.8 mg (difference: −0.60, 95% CI: −0.83 to −0.38; p < 0.0001). For both ITT and completer populations, liraglutide was more effective in reducing HbA1c, FPG and weight. Over 2 years, rates of minor hypoglycaemia [self-treated plasma glucose <3.1 mmol/l (<56 mg/dl)] were significantly lower with liraglutide 1.2 mg and 1.8 mg compared with glimepiride (p < 0.0001).

Conclusion: Liraglutide monotherapy for 2 years provides significant and sustained improvements in glycaemic control and body weight compared with glimepiride monotherapy, at a lower risk of hypoglycaemia.

Failure of secretion of the incretin hormone glucagon-like peptide-1 (GLP-1) plays a prominent role in type 2 diabetes, and restoration of GLP-1 action is an important therapeutic objective. Although the short duration of action of GLP-1 renders it unsuited to therapeutic use, 2 long-acting GLP-1 receptor agonists, exenatide and liraglutide, represent a significant advance in treatment. In controlled trials, both produce short-term glucose-lowering effects, with the reduction in hemoglobin A1c of up to 1.3%. These responses are often superior to those observed with additional oral agents. However, unlike sulfonylureas, thiazolidinediones, or insulin, all of which lead to significant weight gain, GLP-1 receptor agonists uniquely result in long-term weight loss of around 5 kg, and higher doses may enhance this further. Reduction in blood pressure of 2–7 mm Hg also has been observed. Both drugs produce transient mild gastrointestinal side effects; although mild hypoglycemia can occur, this is usually in combination with other hypoglycemic therapies. However, serious hypoglycemia and acute pancreatitis are rare. The once-daily dosage of liraglutide makes it more convenient than twice-daily dosage of prandial exenatide, and a superior glucose-lowering effect was observed in the only head-to-head comparison reported so far. Besides cost, these considerations currently favor liraglutide over exenatide. Further studies are needed to confirm long-term safety, and most importantly, that short-term benefits translate into long-term reductions of diabetes-related cardiovascular events and other complications.

Type 2 diabetes mellitus (T2DM) is a progressive disease associated with significant morbidity and mortality. There is good evidence that intensive glycemic control reduces the development and progression of complications in patients with diabetes. In order to achieve glycemic targets, patients often require a combination of oral therapy and/or insulin in addition to lifestyle modification. Unfortunately many currently available therapies for T2DM are associated with weight gain and hypoglycemia resulting in poor compliance and subsequent worsening glycemic control. Glucagon like peptide-1 (GLP-1) is an incretin hormone secreted from the small intestine that lowers fasting and postprandial glucose through multiple mechanisms including glucose-dependent insulin secretion, reduction of glucagon secretion, delaying gastric emptying and increased satiety. Liraglutide is a long acting GLP-1 mimetic that is administered once a day by subcutaneous injection and is now licensed for the treatment of T2DM. Phase 3 clinical trials have demonstrated beneficial effects on glycemic control and weight with liraglutide therapy. Within this article, we provide an overview of pharmacology, efficacy, safety and patient experience on liraglutide in the management of T2DM.

Type 2 diabetes mellitus (T2DM) is a progressive disease associated with significant morbidity and mortality. Even though progress have been accomplished in the management of type 2 diabetes, current treatment preferences for patients with this disease still fall short to address disease progression. With the present therapy, glycaemic control remains suboptimal and are often associated with weight gain and hypoglycaemia. Glucagon like peptide-1 (GLP-1) is an incretin hormone secreted from the small intestine that lowers fasting and postprandial glucose through multiple mechanisms including glucose-dependent insulin secretion, reduction of glucagon secretion, delaying gastric emptying and increased satiety. Liraglutide, a human glucagon-like peptide 1 (GLP-1) analogue is a treatment for T2DM that is administered as a once-daily subcutaneous injection. The efficacy and tolerability of liraglutide at doses of 0.6, 1.2, and 1.8 mg for T2DM, in combination with, and compared with, other T2DM treatments were investigated in the Liraglutide Effect and Action in Diabetes (LEAD) Phase III clinical trial program. In the LEAD trial, treatment with liraglutide was associated with substantial improvements in glycaemic control and low risk of hypoglycaemia. In addition liraglutide significantly improved β-cell function, reduced systolic blood pressure (BP) and induced weight loss. Overall, liraglutide was well tolerated. Recent data on safety and efficacy of liraglutide from real-life clinical practice settings also reiterate the better therapeutic profile of this molecule. Based on results from the LEAD programme, and real-life clinical experience, liraglutide has been demonstrated as an effective therapeutic intervention even at the early stage of diabetes regardless of with what, it has been used.

Introduction

Glucagon-like peptide-1 (GLP-1) has been the focus of considerable research activity in the treatment of type 2 diabetes mellitus (T2DM) because the incretin effect is significantly reduced or absent in individuals with T2DM. Thus, pharmacologic efforts to develop medications that mimic the actions of GLP-1 have become a target for improving or reversing chronic hyperglycemia. Two GLP-1 receptor agonists are commercially available: exenatide twice daily (b.i.d.) and liraglutide once daily (q.d.). Targeted and individualized intensification of diabetes management can best be accomplished with a thorough understanding of these new medications.

Methods

Information was gathered through a search of MEDLINE and PubMed for GLP-1 and glycemic management in patients with type 2 diabetes.

Results

Activation of the GLP-1 receptors on the β-cells results in enhanced levels of insulin biosynthesis, β-cell proliferation, resistance to β-cell apoptosis, and enhanced β-cell survival in both humans and rodents; yet, the risk of hypoglycemia is minimized because insulin production and exocytosis occurs in a glucose-dependent manner. The efficacy and safety of the two commercially available GLP-1 receptor agonists, liraglutide and exenatide, in managing postprandial glycemia have been well documented in numerous clinical trials, in which reductions in glycosylated hemoglobin (HbA1c) levels of −0.79% to −1.12% have been demonstrated. Weight reduction/maintenance and improvements in blood pressure and lipidemia have also been reported.

Conclusion

Because GLP-1 receptor agonists work in a glucose-dependent manner, they are likely to reduce hyperglycemia safely, without a marked fluctuation toward hypoglycemia. In the process of acutely restoring β-cell function, GLP-1 agonists may allow patients to achieve HbA1c <7% without experiencing weight gain or hypoglycemia. The ability of GLP-1 receptor agonists to improve blood pressure and postprandial lipidemia in the context of weight neutrality or weight loss may have the potential to ameliorate some of the cardiovascular risks observed in patients with T2DM.