Assessing the general safety and tolerability of vildagliptin: value of pooled analyses from a large safety database versus evaluation of individual studies

A comparative study of acarbose, vildagliptin and saxagliptin intended for better efficacy and safety on type 2 diabetes mellitus treatment

As a complicated metabolic disorder, type 2 diabetes mellitus (T2DM) is becoming a major health concern worldwide. Drugs including acarbose, saxagliptin and vildagliptin are applied, but their efficacy is still required to be compared. Therefore, the study aimed to evaluate the efficacy and safety of acarbose, saxagliptin and vildagliptin in the treatment of T2DM. Ninety patients diagnosed with T2DM were treated with acarbose, saxagliptin and vildagliptin, respectively (30 patients for each drug). All patients were examined at 0, 4 and 12 weeks after treatment with vital signs recorded. Fasting blood glucose and blood biochemical indices were analyzed. In addition, fecal samples were taken for microbial macrogenome sequencing and safety evaluation within 12 weeks after treatment. Blood glucose level decreased at 4 and 12 weeks after treatment, and the total cholesterol (TC) and high-density lipoprotein (HDL) levels at 12 weeks were different. Genus abundance of intestinal flora was altered at different time points. Acarbose increased Butyricimonas level first and then decreased it during drug treatment. Saxagliptin increased Megamonas and decreased Turicibacter genus level gradually. Pseudomonas, Klebsiella, Blautia, Faecalibacterium and Roseburia levels fluctuated after Vildagliptin treatment, which increased fasting C-peptide level greater than the other two drugs. Saxagliptin showed higher adverse reactions than acarbose and vildagliptin. Collectively, acarbose, vildagliptin, and saxagliptin can effectively reduce the HbA1c level and affect the intestinal flora distribution in T2DM patients, and the adverse reactions of acarbose and vildagliptin are less than saxagliptin, providing alternative strategies for the treatment of T2DM.

Dipeptidyl peptidase 4 inhibitors in the treatment of type 2 diabetes mellitus

Dipeptidyl peptidase 4 inhibitors (DPP4i) have been available for treating type 2 diabetes mellitus since 2006. Although they are a diverse group, DPP4i are all small, orally available molecules that interact with the catalytic site of DPP4 without disturbing any of its other known functions, including its effects on the immune system. DPP4i have no intrinsic glucose-lowering activity, so their efficacy as anti-diabetic agents is related directly to their ability to inhibit DPP4 activity and is mediated through the effects of the substrates they protect. Of these, the incretin hormone, glucagon-like peptide 1, is probably the most important. As the effects of glucagon-like peptide 1 are glucose-dependent, the risk of hypoglycaemia with DPP4i is low. Class effects, which are directly related to the mechanism of action, are common to all DPP4i; these include their overall good safety profile and tolerability, as well as their efficacy in improving glycaemic control, but also, potentially, a small increased risk of acute pancreatitis. Compound-specific effects are those related to their differing chemistries and/or pharmacokinetic profiles. These compound-specific effects could affect the way in which individual DPP4i are used therapeutically and potentially explain off-target adverse effects, such as hospitalization for heart failure, which is seen only with one DPP4i. Overall, DPP4i have a favourable therapeutic profile and are safe and effective in the majority of patients with type 2 diabetes mellitus.

Rationale and methodology for a European pooled analysis of postmarketing interventional and observational studies of insulin glargine 300 U/mL in diabetes: protocol of REALI project

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a common and heterogeneous disease. Using advanced analytic approaches to explore real-world data may identify different disease characteristics, responses to treatment and progression patterns. Insulin glargine 300 units/mL (Gla-300) is a second-generation basal insulin analogue with preserved glucose-lowering efficacy but reduced risk of hypoglycaemia. The purpose of the REALI pooled analysis described in this paper is to advance the understanding of the effectiveness and real-world safety of Gla-300 based on a large European patient database of postmarketing interventional and observational studies.

METHODS AND ANALYSIS

In the current round of pooling, REALI will include data from up to 10 000 subjects with diabetes mellitus (mostly T2DM) from 20 European countries. Outcomes of interest include change from baseline to week 24 in haemoglobin A_1c, fasting plasma glucose, self-measured plasma glucose, body weight, insulin dose, incidence and rate of any-time-of-the-day and nocturnal hypoglycaemia. The data pool is being investigated using two complementary methodologies: a conventional descriptive, univariate and multivariable prognostic analysis; and a data-mining approach using subgroup discovery to identify phenotypic clusters of patients who are highly associated with the outcome of interest. By mid-2019, deidentified data of 7584 patients were included in the REALI database, with a further expected increase in patient number in 2020 as a result of pooling additional studies.

ETHICS AND DISSEMINATION

The proposed study does not involve collection of primary data. Moreover, all individual study protocols were approved by independent local ethics committees, and all study participants provided written informed consent. Furthermore, patient data is deidentified before inclusion in the REALI database. Hence, there is no requirement for ethical approval. Results will be disseminated via peer-reviewed publications and presentations at international congresses as data are analysed.

Antidiabetic agents in patients with hepatic impairment

Chronic liver disease (CLD) often coexists with type 2 diabetes mellitus, making diabetes management a challenge to the clinician. It is well known that liver is the major site of drug metabolism, and, therefore, its impairment affects hepatic metabolism of many antidiabetic agents. Furthermore, patients with CLD have serious comorbidities such as impaired renal function, hypoalbuminemia, lactic acidosis, hypoglycemia and malnutrition, making their treatment even more difficult. On the other hand, most of the antidiabetic agents, with the exception of insulin, need dosage titration due to alterations to their pharmacokinetics in patients with CLD. For well-established antidiabetic treatments, like metformin and sulfonylureas there are studies regarding their dosage chance in these patients. However, despite the growing problem of management of diabetes in patients with CLD the existing literature data, especially on newer antidiabetic agents, are limited and, furthermore, no direct guidelines exist. Therefore, in the present review article we try to summarize the existing literature data regarding management of diabetes in patients with CLD.

Association between vildagliptin and risk of angioedema, foot ulcers, skin lesions, hepatic toxicity, and serious infections in patients with type 2 diabetes mellitus: A European multidatabase, noninterventional, postauthorization safety study

OBJECTIVES

This noninterventional, multidatabase, analytical cohort study explored whether vildagliptin is associated with an increased risk of specific safety events of interest, namely angioedema, foot ulcers, or skin lesions, adverse hepatic events, or serious infections compared with other noninsulin antidiabetic drugs (NIADs) using real-world data from five European electronic healthcare databases.

DESIGN

Patients with type 2 diabetes mellitus aged ≥18 years on NIAD treatment were included between January 2005 and June 2014. Adjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for the outcomes of interest were estimated using negative binomial regression.

PATIENTS

Approximately 2.8% of the included patients (n = 738 054) used vildagliptin at any time during the study, with an average follow-up time of 1.4 years.

RESULTS

The adjusted IRRs (vildagliptin vs. other NIADs) were in the range of 0.87-3.71 (angioedema), 0.73-1.19 (foot ulcers), 0.37-1.18 (skin lesions), 0.24-1.14 (composite of foot ulcer or skin lesions), 0.29-0.55 (serious hepatic events), and 0.59-1.04 (serious infections), with no lower bound of the 95% CIs > 1.

CONCLUSIONS

Overall, there was no increased risk of the events of interest in association with vildagliptin use compared with other NIADs.

Physiology and Pharmacology of DPP-4 in Glucose Homeostasis and the Treatment of Type 2 Diabetes

Dipeptidyl peptidase-4 (DPP-4), also known as the T-cell antigen CD26, is a multi-functional protein which, besides its catalytic activity, also functions as a binding protein and a ligand for a variety of extracellular molecules. It is an integral membrane protein expressed on cells throughout the body, but is also shed from the membrane and circulates as a soluble protein in the plasma. A large number of bioactive molecules can be cleaved by DPP-4 in vitro, but only a few of these have been demonstrated to be physiological substrates. One of these is the incretin hormone, glucagon-like peptide-1 (GLP-1), which plays an important role in the maintenance of normal glucose homeostasis, and DPP-4 has been shown to be the key enzyme regulating its biological activity. This pathway has been targeted pharmacologically through the development of DPP-4 inhibitors, and these are now a successful class of anti-hyperglycaemic agents used to treat type 2 diabetes (T2DM). DPP-4 may additionally influence metabolic control via its proteolytic effect on other regulatory peptides, but it has also been reported to affect insulin sensitivity, potentially mediated through its non-enzymatic interactions with other membrane proteins. Given that altered expression and activity of DPP-4 are associated with increasing body mass index and hyperglycaemia, DPP-4 has been proposed to play a role in linking obesity and the pathogenesis of T2DM by functioning as a local mediator of inflammation and insulin resistance in adipose and hepatic tissue. As well as these broader systemic effects, it has also been suggested that DPP-4 may be able to modulate β-cell function as part of a paracrine system involving GLP-1 produced locally within the pancreatic islets. However, while it is evident that DPP-4 has the potential to influence glycaemic control, its overall significance for the normal physiological regulation of glucose homeostasis in humans and its role in the pathogenesis of metabolic disease remain to be established.

Clinical Safety and Tolerability of Vildagliptin - Insights from Randomised Trials, Observational Studies and Post-marketing Surveillance

Vildagliptin is one of the most extensively studied dipeptidyl peptidase-4 (DPP-4) inhibitors in terms of its clinical utility. Over the last decade, a vast panorama of evidence on the benefit-risk profile of vildagliptin has been generated in patients with type 2 diabetes mellitus (T2DM). In this article, we review the cumulative evidence on the safety of vildagliptin from the clinical development programme, as well as reports of rare adverse drug reactions detected during the post-marketing surveillance of the drug. Across clinical studies, the overall safety and tolerability profile of vildagliptin was similar to placebo, and it was supported by real-world data in a broad population of patients with T2DM, making DPP-4 inhibitors, like vildagliptin, a safe option for managing patients with T2DM.

Dipeptidyl peptidase-4 inhibitors and risk of arthralgia: A systematic review and meta-analysis

BACKGROUND

The US Food and Drug Administration has warned that treatment with dipeptidyl peptidase (DPP)-4 inhibitors may promote serious arthralgia. However, the clinical evidence for this is relatively lacking.

OBJECTIVE

For this reason, a systematic review and meta-analysis of randomized controlled trials (RCTs) were carried out to determine the relationship between DPP-4 inhibitors and risk of arthralgia, and also to investigate any potential risk factors.

METHODS

An extensive electronic search for RCTs comparing DPP-4 inhibitors with any comparators was performed up to July 2016. Outcomes of interest were overall and serious arthralgia. Summary risk ratios (RRs) with 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 67 RCTs (involving 79,110 patients) was ultimately included. Pooled results showed that DPP-4 inhibitors were associated with a slightly but significantly increased risk of overall arthralgia (RR: 1.13, 95% CI: 1.04-1.22; P=0.003) and a non-significant increased risk of serious arthralgia (RR: 1.44, 95% CI: 0.83-2.51; P=0.20). Also, subgroup analyses showed that add-on/combination therapy and longer diabetes duration (>5years) were possible factors associated with the increased risk of overall arthralgia.

CONCLUSION

These findings suggest that DPP-4 inhibitors can increase the risk of arthralgia. Thus, the benefits of glycaemic control must be weighed against the risk of arthralgia when prescribing DPP-4 inhibitors. Further studies are now needed to identify and confirm these risk factors.

Pattern of Onset and Risk Factors for Peripheral Oedema During Vildagliptin Use: Analysis from the Vildagliptin Prescription-Event Monitoring Study in England

INTRODUCTION

Clinical trials have identified peripheral oedema (PO) as an adverse event of vildagliptin (an oral anti-diabetic drug [OAD]). A post-marketing study (PMS) was conducted to advance the understanding of vildagliptin use and particular safety concerns identified within the risk-management plan. PMS objectives included comparing the hazards between vildagliptin monotherapy and combination therapy for selected a priori identified risks, including PO.

AIM

This study was a per-protocol supplementary analysis to investigate the pattern of onset and effect of vildagliptin combination therapy on PO risk.

METHODS

The PMS used an observational cohort design. OAD exposure, selected risk factors and outcome data were collected from general practitioners in England regarding vildagliptin users for the 6-month period after starting treatment. Data analysis comprised univariate case/non-case analysis, time-to-onset analysis and Cox proportional hazard models to estimate hazard ratios (HR) of PO adjusting for selected patients' baseline characteristics.

RESULTS

The study cohort included 4828 patients (median age 63 years; interquartile range [IQR] 54-71), 2692 of whom were male (55.8 %). The crude cumulative hazard of PO was 19.09 cases (95 % confidence interval [CI] 13.54-26.10) per 1000 person-years; 50 % of cases occurred during the first 34 days of treatment. A significantly faster time to PO onset was observed in patients prescribed concomitant sulfonylureas versus other treatment combinations (log rank test [LRT] p = 0.0365); in patients with a prior history of PO (LRT p < 0.001), arrhythmia (LRT p = 0.0003) or hypertension (LRT p = 0.0125); and in patients aged ≥60 years (LRT p = 0.0047). Similarly, the case/non-case univariate analysis indicated that patients with PO were older; had a higher prevalence of a history of either arrhythmia, hypertension or PO; and frequently used a sulfonylurea in combination. In the hazard function analysis, only sex and prior PO history had a profound effect on risk of PO after starting vildagliptin. Furthermore, effect modification was observed between sex and prior PO history; in male patients of average age (62 years), the HR was 12.84 (95 % CI 4.96-33.23); in females, it was 1.44 (95 % CI 0.32-6.40).

CONCLUSIONS

In this planned supplementary analysis, the findings suggest that PO occurred most frequently within 1 month after starting treatment with vildagliptin, and previous PO history and male sex in elderly patients were important predictors of this risk. The observation that concomitant use of a sulfonylurea may also increase PO risk early after starting treatment should be taken into consideration if prescribing OADs in combination with vildagliptin.

Drug development from the bench to the pharmacy: with special reference to dipeptidyl peptidase-4 inhibitor development

The dipeptidyl peptidase-4 (DPP-4) inhibitor concept is an example of prospective drug design and development based upon a distinct endocrine hypothesis. The design of enzyme inhibitors is a pragmatic approach to drug design; being compatible with the identification and optimization of small molecules that have properties commensurate with oral administration, as well as acceptable drug metabolism, distribution and elimination characteristics. Glucagon-like peptide 1 (GLP-1), a hormone with a spectrum of favourable metabolic actions, including glucose-dependent stimulation of insulin and inhibition of glucagon secretion, provided the endocrine basis from which the idea of using DPP-4 inhibitors as anti-diabetic agents was developed. The origin of the DPP-4 inhibitor concept was inspired by the angiotensin-converting enzyme inhibitor approach, which succeeded in establishing a class of extensively used therapeutic agents for the treatment of cardiovascular disorders.

Comparative review of dipeptidyl peptidase-4 inhibitors and sulphonylureas

Type 2 diabetes (T2DM) is a progressive disease, and pharmacotherapy with a single agent does not generally provide durable glycaemic control over the long term. Sulphonylurea (SU) drugs have a history stretching back over 60 years, and have traditionally been the mainstay choice as second-line agents to be added to metformin once glycaemic control with metformin monotherapy deteriorates; however, they are associated with undesirable side effects, including increased hypoglycaemia risk and weight gain. Dipeptidyl peptidase (DPP)-4 inhibitors are, by comparison, more recent, with the first compound being launched in 2006, but the class now globally encompasses at least 11 different compounds. DPP-4 inhibitors improve glycaemic control with similar efficacy to SUs, but do not usually provoke hypoglycaemia or weight gain, are relatively free from adverse side effects, and have recently been shown not to increase cardiovascular risk in large prospective safety trials. Because of these factors, DPP-4 inhibitors have become an established therapy for T2DM and are increasingly being positioned earlier in treatment algorithms. The present article reviews these two classes of oral antidiabetic drugs (DPP-4 inhibitors and SUs), highlighting differences and similarities between members of the same class, as well as discussing the potential advantages and disadvantages of the two drug classes. While both classes have their merits, the choice of which to use depends on the characteristics of each individual patient; however, for the majority of patients, DPP-4 inhibitors are now the preferred choice.

Vildagliptin efficacy in combination with metformin among Jordanian patients with type 2 diabetes mellitus inadequately controlled with metformin

Objective: To assess the efficacy and safety of vildagliptin added to metformin in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin monotherapy.

Methods: This was a 12-week prospective observational study where vildagliptin 50 mg twice daily was added to patients with T2DM inadequately controlled (glycosylated hemoglobin type A1c (Hba1c) 7–10%) by a daily dose of metformin ≥1700 mg between June 2012 and May 2013. Efficacy was assessed by change in Hba1c and fasting plasma glucose (FPG) levels, and safety was assessed by reported adverse events (AEs).

Results: A total of 58 patients were enrolled in this study. Their age ranged between 39.0 and 71.0 years, with a mean of 52.6 years, and a standard deviation (SD) of 7.8. The average duration of diabetes mellitus (DM) was 4.0 years (SD 3.0) and half of the patients have had DM for more than three years. The mean baseline levels of Hba1c and FPG were 8% and 10.8 mmol/L, respectively. Patients treated with vildagliptin achieved clinically significant reductions in Hba1c of 1.1% (p value <.005) and reduction in FPG of 1.8 mmol/L (p value <.005) from baseline. Overall, 62.1% had achieved the target of Hba1c of <7% after vildagliptin use. Greater reductions in Hba1c were linked to higher baseline levels as well as to the daily frequency of metformin use. Mild AEs were reported by 16 patients. There was no incidence of hypoglycemia and there were no significant changes in body weight after treatment.

Conclusions: Vildagliptin as add-on therapy to metformin improved glycemic control and was highly tolerable in T2DM patients who were inadequately controlled by metformin monotherapy.

Clinical effectiveness and safety of vildagliptin in >19 000 patients with type 2 diabetes: the GUARD study

The present GUARD study was a prospective, non-interventional study evaluating the clinical effectiveness, safety and tolerability of vildagliptin with or without metformin in adult patients with type 2 diabetes mellitus (T2DM) studied in routine clinical practice. Patients were enrolled from countries across four geographical regions. The primary endpoint was change in glycated haemoglobin (HbA1c) concentration from baseline after 24 weeks of treatment with vildagliptin with or without metformin. Of 19 331 patients analysed, 3511 received vildagliptin and 15 820 received vildagliptin plus metformin. At week 24, the mean HbA1c was reduced significantly from baseline by -1.27% (vildagliptin: -1.17%; vildagliptin plus metformin: -1.29%; p < 0.0001). Significant reductions in HbA1c from baseline were consistently reported regardless of patient age, body mass index (BMI) or baseline HbA1c. Weight and BMI were also significantly reduced from baseline. Vildagliptin treatment with or without metformin was generally well tolerated. It provided clinically relevant glycaemic and weight control, and was well tolerated in a large multi-ethnic population of patients with T2DM studied in routine clinical practice.

Pharmacokinetics in patients with chronic liver disease and hepatic safety of incretin-based therapies for the management of type 2 diabetes mellitus

Patients with type 2 diabetes mellitus have an increased risk of chronic liver disease (CLD) such as non-alcoholic fatty liver disease and steatohepatitis, and about one-third of cirrhotic patients have diabetes. However, the use of several antidiabetic agents, such as metformin and sulphonylureas, may be a concern in case of hepatic impairment (HI). New glucose-lowering agents targeting the incretin system are increasingly used for the management of type 2 diabetes. Incretin-based therapies comprise oral inhibitors of dipeptidyl peptidase-4 (DPP-4) (gliptins) or injectable glucagon-like peptide-1 (GLP-1) receptor agonists. This narrative review summarises the available data regarding the use of both incretin-based therapies in patients with HI. In contrast to old glucose-lowering agents, they were evaluated in specifically designed acute pharmacokinetic studies in patients with various degrees of HI and their hepatic safety was carefully analysed in large clinical trials. Only mild changes in pharmacokinetic characteristics of DPP-4 inhibitors were observed in patients with different degrees of HI, presumably without major clinical relevance. GLP-1 receptor agonists have a renal excretion rather than liver metabolism. Specific pharmacokinetic data in patients with HI are only available for liraglutide. No significant changes in liver enzymes were reported with DPP-4 inhibitors or GLP-1 receptor agonists, alone or in combination with various other glucose-lowering agents, in clinical trials up to 2 years in length. On the contrary, preliminary data suggested that incretin-based therapies may be beneficial in patients with CLD, more particularly in the presence of non-alcoholic fatty liver disease. Nevertheless, caution should be recommended, especially in patients with advanced cirrhosis, because of a lack of clinical experience with incretin-based therapies in these vulnerable patients.

The efficacy of vildagliptin concomitant with insulin therapy in type 2 diabetic subjects

BACKGROUND

In Japan, dipeptidyl peptidase 4 (DPP4) inhibitors have become standard therapeutic agents for type 2 diabetes, and numbers of patients receiving insulin therapy combined with DPP4 inhibitors, which is a highly effective regimen, are increasing.

METHODS

In this study, we evaluated the efficacy of vildagliptin administered at the dose of 100 mg twice daily in 57 patients with type 2 diabetes already receiving insulin treatment.

RESULTS

The 36 patients who simply received add-on vildagliptin showed a 0.6% decrease in HbA1c levels, despite a marked insulin dose reduction, mainly bolus insulin, of approximately 8.3 units. In addition, body mass index exhibited a significant negative correlation with the efficacy of vildagliptin, i.e., ΔHbA1c. On the other hand, the 21 patients switched from 50 mg of sitagliptin to vildagliptin showed HbA1c decreases approaching 0.7%.

CONCLUSION

Taking into consideration that twice-daily oral vildagliptin has already been reported to be advantageous in reducing postprandial hyperglycemia, this drug was suggested to be more effective in reducing HbA1c than sitagliptin under conditions in which it is used as a supplement to basal insulin, as in this study.

Effectiveness and Tolerability of Second-Line Therapy with Vildagliptin Versus Other Oral Agents in Type 2 Diabetes (EDGE): Post Hoc Sub-Analysis of Bulgarian Data

OBJECTIVES

Metformin is an established first-line treatment for type 2 diabetes mellitus (T2DM) patients but intensification of oral anti-diabetic therapy is usually required over time. The effectiveness of diabetes control with vildaGliptin and vildagliptin/mEtformin (EDGE) study compared effectiveness and safety of vildagliptin and other oral anti-diabetic drugs (OAD) in 45,868 patients worldwide with inadequately controlled T2DM by monotherapy under real-life conditions. Here, we present effectiveness results for patients receiving vildagliptin (vildagliptin cohort) or another OAD (comparator cohort) add-on to monotherapy in Bulgaria.

METHODS

The eligible diabetes patients inadequately controlled with current monotherapy were assigned to add-on treatment, which was chosen by the physician based on patient's need. Effectiveness was assessed by glycated hemoglobin (HbA1c) drop and by means of a composite endpoint assessing the proportion of patients responding to treatment (HbA1c <7%) without proven hypoglycemic event and significant weight gain (>5%) after 12 months of treatment.

RESULTS

In total, 754 patients were enrolled in Bulgaria, 384 in the vildagliptin cohort and 369 in the comparator cohort. Mean HbA1c change from baseline was significantly higher with vildagliptin compared to the comparator (-1.35% in the vildagliptin cohort and -0.55% in the comparator cohort, P < 0.001). In the vildagliptin cohort, a higher proportion of patients reached the composite endpoint (HbA1c <7%, no hypoglycemic events, no weight gain) when compared to the comparator cohort (vildagliptin: 32.3%; comparator: 8.4%; P < 0.001). Overall, vildagliptin was well tolerated with similarly low incidences of total adverse events (3.4% versus 1.9% in the comparator group) and serious adverse events (2.3% versus 1.1% in the comparator group).

CONCLUSIONS

In real-life clinical practice in Bulgaria, vildagliptin is associated with a greater HbA1c drop, and a higher proportion of patients reaching target HbA1c without hypoglycemia and weight gain compared to comparator.

Efficacy and Safety of Vildagliptin as Add-on to Metformin in Japanese Patients with Type 2 Diabetes Mellitus

INTRODUCTION

The objective of this study was to evaluate the efficacy and safety of vildagliptin, a potent dipeptidyl peptidase-4 inhibitor, as an add-on to metformin in Japanese patients with type 2 diabetes mellitus (T2DM).

METHODS

This multicenter, 12-week, randomized, double-blind, placebo-controlled, parallel-arm study compared vildagliptin 50 mg bid with placebo in T2DM patients who were inadequately controlled [glycosylated hemoglobin (HbA1c) 7.0-10.0%] on a stable daily dose of metformin monotherapy (250 mg bid or 500 mg bid).

RESULTS

A total of 139 patients were randomized to receive either vildagliptin (n = 69) or placebo (n = 70). Patient demographics were comparable between the groups at baseline. After 12 weeks of treatment, adjusted mean change in HbA1c was -1.1% in the vildagliptin group (baseline 8.0%) and -0.1% in the placebo group (baseline 8.0%), with a between-treatment difference of -1.0% (P < 0.001). Vildagliptin showed a similar reduction in HbA1c of -1.1% for both the subpopulations of patients receiving metformin 250 mg bid or 500 mg bid (P < 0.001 vs. baseline). Significantly more patients in the vildagliptin group achieved an HbA1c target of ≤6.5% (30.9%) and <7.0% (64.1%) compared with the placebo group (P < 0.001). The between-treatment difference in adjusted mean change in fasting plasma glucose was -1.6 mmol/L (P < 0.001) in favor of vildagliptin. Patients in the vildagliptin and placebo groups reported comparable incidences of adverse events (44.1% vs. 41.4%). No deaths or hypoglycemic events were reported in the study.

CONCLUSIONS

Vildagliptin 50 mg bid added to metformin improved glycemic control without any tolerability issues and hypoglycemia in Japanese patients with T2DM inadequately controlled on metformin monotherapy.

Pharmacokinetic and toxicological considerations for the treatment of diabetes in patients with liver disease

INTRODUCTION

Patients with type 2 diabetes have an increased risk of chronic liver disease (CLD) such as non-alcoholic fatty liver disease and steatohepatitis and about one-third of cirrhotic patients have diabetes. However, the use of several antidiabetic agents may be a cause for concern in the case of hepatic impairment (HI).

AREAS COVERED

An extensive literature search was performed to analyze the influence of HI on the pharmacokinetics (PK) of glucose-lowering agents and the potential consequences for clinical practice as far as the efficacy/safety balance of their use in diabetic patients with CLD is concerned.

EXPERT OPINION

Almost no PK studies have been published regarding metformin, sulfonylureas, thiazolidinediones and α-glucosidase inhibitors in patients with HI. Only mild changes in PK of glinides, dipeptidyl peptidase-4 inhibitors and sodium glucose cotransporters type 2 inhibitors were observed in dedicated PK studies in patients with various degrees of HI, presumably without major clinical relevance although large clinical experience is lacking. Glucagon-like peptide-1 receptor agonists have a renal excretion rather than liver metabolism. Rare anecdotal case reports of hepatotoxicity have been described with various glucose-lowering agents contrasting with numerous reassuring data. Nevertheless, caution should be recommended, especially in patients with advanced cirrhosis, including with the use of metformin.

Experience with vildagliptin in patients ≥75 years with type 2 diabetes and moderate or severe renal impairment

INTRODUCTION

Patients with type 2 diabetes (T2DM) are at increased risk for renal impairment (RI) and, in addition, there is an age-related decline in renal function. At the same time, T2DM treatment is more complex and treatment options are more limited in elderly patients as well as patients with RI, with the patient population ≥75 years with moderate or severe RI posing unique challenges, in particular, the high risk and more severe consequences of hypoglycemia. It was, therefore, of interest to assess the efficacy and tolerability of the dipeptidyl peptidase-4 inhibitor vildagliptin in patients with T2DM ≥75 years who also have moderate or severe RI.

METHODS

In this sub-analysis of data derived from a previously described randomized, double-blind, parallel-group, 24-week study, 105 patients (50 randomized to vildagliptin 50 mg qd and 55 to placebo) ≥75 years (mean age ~78 years) with T2DM and moderate or severe RI (mean baseline estimated glomerular filtration rate ~35 ml/min/1.73 m(2)) were included.

RESULTS

The adjusted mean change in glycated hemoglobin (HbA1c) with vildagliptin was -1.0% from a baseline of 7.8% (between-group difference -0.8%; p < 0.001). This improvement in glycemic control was not associated with an increased risk of hypoglycemia; the rate of confirmed hypoglycemia was 0.49 events per patient-year with vildagliptin and 0.96 events per patient-year with placebo (not significant). Weight remained stable with vildagliptin treatment. Adverse events (AEs) (58.0% vs. 72.7%), serious AEs (14.0% vs. 16.4%), discontinuations due to AEs (4.0% vs. 9.1%) and deaths (0% vs. 5.5%) were reported at a comparable or lower frequency in patients receiving vildagliptin versus patients receiving placebo.

CONCLUSION

In this uniquely fragile elderly population ≥75 years with T2DM and moderate or severe RI, vildagliptin was well tolerated and efficacious, with no increase in the rate of hypoglycemia compared to placebo despite the marked improvement in glycemic control.

Effectiveness and tolerability of second-line therapy with vildagliptin vs. other oral agents in type 2 diabetes: a real-life worldwide observational study (EDGE)

AIM

Real-life studies are needed to confirm the clinical relevance of findings from randomised controlled trials (RCTs). This study aimed to assess the effectiveness and tolerability of vildagliptin add-on vs. other oral antihyperglycaemic drugs (OADs) added to OAD monotherapy in a real-life setting, and to explore the advantages and limitations of large-scale 'pragmatic' trials.

METHODS

EDGE was a prospective, 1-year, worldwide, real-life observational study in which 2957 physicians reported on the effects of second-line OADs in 45,868 patients with T2DM not reaching glycaemic targets with monotherapy. Physicians could add any OAD, and patients entered either vildagliptin or (pooled) comparator cohort. The primary effectiveness and tolerability end-point (PEP) evaluated proportions of patients decreasing HbA(1c) > 0.3%, without hypoglycaemia, weight gain, peripheral oedema or gastrointestinal side effects. The most clinically relevant secondary end-point (SEP 3) was attainment of end-point HbA(1c) < 7% without hypoglycaemia or ≥ 3% increase in body weight.

RESULTS

In this large group of T2DM patients, a second OAD was added at mean HbA(1c) of 8.2 ± 1.3%, with no baseline HbA(1c) difference between cohorts. Second-line OAD therapy attained the PEP in the majority of patients, with higher attainment in those prescribed a vildagliptin-based regimen. The adjusted odds ratio was 1.49 (95% CI: 1.42, 1.55; p < 0.001). In patients with baseline HbA(1c) ≥ 7%, SEP 3 was achieved by 35% of patients on a vildagliptin-based combination and by 23% of those receiving comparator combinations. The adjusted odds ratio was 1.96 (95% CI: 1.85, 2.07; p < 0.001). Safety events were reported infrequently and safety profiles of vildagliptin and other OADs were consistent with previous data.

CONCLUSION

EDGE demonstrates that in a 'real-life' setting, vildagliptin as second OAD can lower HbA(1c) to target without well-recognised OAD side effects, more frequently than comparator OADs. In addition, EDGE illustrates that conducting large-scale, prospective, real-life studies poses challenges but yields valuable clinical information complementary to RCTs.

Combination therapy with DPP-4 inhibitors and insulin in patients with type 2 diabetes mellitus: what is the evidence?

As type 2 diabetes mellitus (T2DM) progresses, most patients will require insulin replacement therapy. Whether oral antidiabetic drug (OAD) therapy should be retained when initiating insulin is still debated. While the rationale to keep metformin with insulin is strong (mostly as an insulin-sparing agent to limit weight gain), the evidence is less clear for other OADs. In particular, the question now comes up what the expected benefit could be of combining the newer agents, such as the dipeptidyl peptidase-4 (DPP-4) inhibitors with insulin. Additionally, when metformin is no longer a treatment option, as in the case of patients with severe renal impairment, insulin is often used as monotherapy, with little evidence of benefit in maintaining other OADs. In this specific situation, it is also of interest to evaluate the potential benefit of combined treatment with a DPP-4 inhibitor and insulin. Among the classic limitations of insulin therapy in patients with T2DM, hypoglycemia remains a major barrier to glycemic control, along with weight gain exacerbation. The oral DPP-4 inhibitors improve glycemic control by increasing the sensitivity of the islet cells to glucose, and thus are not associated with an increased risk for hypoglycemia and are weight neutral. In addition to the expected benefits associated with limiting insulin dose and regimen complexity, the specific advantages the DPP-4 inhibitor drug class on hypoglycemia and weight gain could justify combining DPP-4 inhibitors with insulin; additionally, a DPP-4 inhibitor may be of special value to decrease glycemic excursions that are not properly addressed by basal insulin therapy and metformin use, even after optimizing titration of the basal insulin. However, given the common original perception that treatment with DPP-4 inhibitors may be less beneficial with increasing disease progression because of the loss of β-cell function, the potential relevance of these agents in the setting of advanced T2DM treated with insulin was not necessarily anticipated. Promising data from studies on the use of these new agents in insulin-treated patients with T2DM have started to emerge. Our article provides a comprehensive overview of the currently available evidence from controlled randomized clinical trials and we discuss the potential role of DPP-4 inhibitors in the this setting. Further clinical experience will allow to fully assess the positioning of these agents in insulin-treated T2DM populations.

Safety and tolerability of sitagliptin in type 2 diabetes: pooled analysis of 25 clinical studies

INTRODUCTION

In a previous pooled analysis of 19 double-blind clinical studies conducted by Merck, which included data available as of July 2009 on 10,246 patients with type 2 diabetes (T2DM), treatment with sitagliptin was shown to be generally well tolerated compared with treatment with control agents. As the sitagliptin clinical development program continues, additional studies with sitagliptin have been completed. The present analysis updates the safety and tolerability assessment of sitagliptin by examining pooled data from 25 double-blind clinical studies.

METHODS

The present analysis included data from 14,611 patients in 25 studies with T2DM who received either sitagliptin 100 mg/day (n = 7,726; sitagliptin group) or a comparator agent (n = 6,885; non-exposed group). These studies represent all randomized, double-blind trials conducted by Merck that included patients treated with the usual clinical dose of sitagliptin (100 mg/day) for between 12 weeks and 2 years, and for which results were available as of December 2011. These studies assessed sitagliptin, versus comparator agents, taken as monotherapy, initial combination therapy with metformin or pioglitazone, or as add-on combination therapy with other antihyperglycemic agents (metformin, pioglitazone, a sulfonylurea ± metformin, insulin ± metformin, or metformin + pioglitazone or rosiglitazone). Patient-level data from each study were used to evaluate between-group differences in the exposure-adjusted incidence rates of adverse events (AEs).

RESULTS

Overall incidence rates of AEs and drug-related AEs were higher in the non-exposed group compared with the sitagliptin group. Incidence rates of specific AEs were generally similar between the two groups, except for higher incidence rates of hypoglycemia related to the greater use of a sulfonylurea and diarrhea related to the greater use of metformin in the non-exposed group, and of constipation in the sitagliptin group. Treatment with sitagliptin was not associated with an increased risk of major adverse cardiovascular events, malignancy, or pancreatitis.

CONCLUSION

In this updated pooled safety analysis of data from 14,611 patients with T2DM, sitagliptin 100 mg/day was generally well tolerated in clinical trials of up to 2 years in duration.

Improved glycaemic control with vildagliptin added to insulin, with or without metformin, in patients with type 2 diabetes mellitus

AIM

The aim of this study is to assess the efficacy and safety of vildagliptin 50 mg bid as add-on therapy to insulin in type 2 diabetes mellitus (T2DM).

METHODS

This is a multicentre, double-blind, placebo-controlled, parallel group, clinical trial in T2DM patients inadequately controlled by stable insulin therapy, with or without metformin. Patients received treatment with vildagliptin 50 mg bid or placebo for 24 weeks.

RESULTS

In all, 449 patients were randomized to vildagliptin (n = 228) or placebo (n = 221). After 24 weeks, the difference in adjusted mean change in haemoglobin A1c (HbA1c) between vildagliptin and placebo was -0.7 ± 0.1% (p < 0.001) in the overall study population, -0.6 ± 0.1% (p < 0.001) in the subgroup also receiving metformin and -0.8 ± 0.2% (p < 0.001) in the subgroup without metformin. Vildagliptin therapy was well tolerated and had a similarly low incidence of hypoglycaemia compared with placebo (8.4 vs. 7.2%, p = 0.66) in spite of improved glycaemic control, and was not associated with weight gain. (+0.1 vs. -0.4 kg).

CONCLUSIONS

Vildagliptin 50 mg bid added to insulin significantly reduced HbA1c in patients with T2DM inadequately controlled by insulin, with or without metformin. Vildagliptin was well tolerated, with a safety profile similar to placebo. These results were achieved without weight gain or an increase in hypoglycaemia incidence or severity in spite of improved glycaemic control.

Clinical evidence and mechanistic basis for vildagliptin's effect in combination with insulin

Due to the progressive nature of type 2 diabetes, many patients need insulin as add-on to oral antidiabetic drugs (OADs) in order to maintain adequate glycemic control. Insulin therapy primarily targets elevated fasting glycemia but is less effective to reduce postprandial hyperglycemia. In addition, the risk of hypoglycemia limits its effectiveness and there is a concern of weight gain. These drawbacks may be overcome by combining insulin with incretin-based therapies as these increase glucose sensitivity of both the α- and β-cells, resulting in improved postprandial glycemia without the hypoglycemia and weight gain associated with increasing the dose of insulin. The dipeptidyl peptidase-IV (DPP-4) inhibitor vildagliptin has also been shown to protect from hypoglycemia by enhancing glucagon counterregulation. The effectiveness of combining vildagliptin with insulin was demonstrated in three different studies in which vildagliptin decreased A1C levels when added to insulin therapy without increasing hypoglycemia. This was established with and without concomitant metformin therapy. Furthermore, the effectiveness of vildagliptin appears to be greater when insulin is used as a basal regimen as opposed to being used to reduce postprandial hyperglycemia, since improvement in insulin secretion likely plays a minor role when relatively high doses of insulin are administered before meals. This article reviews the clinical experience with the combination of vildagliptin and insulin and discusses the mechanistic basis for the beneficial effects of the combination. The data support the use of vildagliptin in combination with insulin in general and, in line with emerging clinical practice, suggest that treating patients with vildagliptin, metformin, and basal insulin could be an attractive therapeutic option.

Studies in rodents with the dipeptidyl peptidase-4 inhibitor vildagliptin to evaluate possible drug-induced pancreatic histological changes that are predictive of pancreatitis and cancer development in man

AIM

The present report summarizes rodent studies with vildagliptin, relevant to predicting pancreatitis or pancreatic cancer in man.

METHODS

As part of the regulatory development program for vildagliptin, a rodent toxicity program included two 104-week rodent (mouse and rat) carcinogenicity studies that were conducted according to guidelines assigned in Food and Drug Administration's Draft Guidance for Industry.

RESULTS

Vildagliptin exposure in animals was evaluated for its effects on endocrine and exocrine pancreas. Two-year carcinogenicity studies were conducted in rats at oral doses up to 900 mg/kg (approximately 200 times the human exposure at the maximum recommended dose) and in mice at oral doses up to 1000 mg/kg (up to 240 times the human exposure at the maximum recommended dose). The results from these studies show the expected preservation and growth of the endocrine β-cells with no significant findings in the exocrine acinar pancreas. There was no evidence of inflammatory infiltrates characteristic of pancreatitis, no palpable mass detection based on gross examination or any microscopic findings indicative of pancreatic islet cell (endocrine), acinar cell (exocrine) or ductal (exocrine) neoplasia in rat or mouse.

CONCLUSIONS

Evaluation of vildagliptin in 2-year preclinical carcinogenicity studies in both rats and mice indicates that while vildagliptin results in pharmacological benefits to the endocrine pancreas, this was not associated with any evidence of pancreatitis, pancreatic islet cell, acinar cell or ductal neoplasia. These data predict no increased risk of pancreatic cancer in man.

Longer term safety of dipeptidyl peptidase-4 inhibitors in patients with type 2 diabetes mellitus: systematic review and meta-analysis

Dipeptidyl peptidase-4 (DPP-4) inhibitors are oral antidiabetic agents that hold the potential of slowing the progress of type 2 diabetes mellitus. Their long-term safety is still a subject of debate. A systematic review of randomized, controlled trials was undertaken to comprehensively profile the safety of chronic treatment of type 2 diabetes mellitus with DPP-4 inhibitors. We searched data sources including MEDLINE, CENTRAL, publishers' and manufacturers' databases. Eligible trials were double-blind, randomized, placebo or active-controlled trials with ≥18 weeks duration in patients with type 2 diabetes reporting safety outcomes. Meta-analysis was performed separately for trials in which the control group received placebo (44 studies), another gliptin (3 studies) and any other antidiabetic drug (20 studies). Risk ratios with 95% confidence intervals were computed using a Mantel-Haenszel fixed-effect model for general safety outcomes, hypoglycaemia and adverse events by system organ class. Of 307 publications retrieved, 67 randomized, controlled trials met the eligibility criteria and were included in this review (4 alogliptin, 8 linagliptin, 8 saxagliptin, 20 sitagliptin, and 27 vildagliptin trials). Adverse events with gliptin treatment were at placebo level (relative risk (RR) 1.02 [0.99, 1.04]). No increased risk of infections was detectable (RR 0.98 [0.93, 1.05] compared to placebo and 1.02 [0.97, 1.07] compared to other antidiabetic drugs). Asthenia (RR 1.57 [1.09, 2.27]) as well as cardiac (RR 1.37 [1.00, 1.89]) and vascular disorders (RR 1.74 [1.05, 2.86] for linagliptin) emerged as adverse events associated with DPP-4 inhibitor treatment. The risk of hypoglycaemia was low with DPP-4 inhibitor treatment (RR 0.92 [0.74, 1.15] compared to placebo, RR 0.20 [0.17, 0.24] compared to sulphonylureas) in the absence of sulphonylurea or insulin co-therapy, but significantly elevated for combination therapy of sulphonylurea or insulin with sitagliptin or linagliptin (RR 1.86 [1.46, 2.37] compared to placebo). A large body of data supports the long-term safety of gliptin treatment and refutes an increased risk of infections. Further research is needed to clarify a possible link to asthenia, cardiac and vascular events. For combination therapy with insulin or insulin secretagogues, a careful choice of the agent used may limit the risk of hypoglycaemia.

Impact of insulin resistance, body mass index, disease duration, and duration of metformin use on the efficacy of vildagliptin

INTRODUCTION

The optimal stage for dipeptidyl peptidase-4 (DPP-4) inhibitor therapy in the course of type 2 diabetes mellitus (T2DM) is still under discussion, with often a perception that treatment with these agents may be less beneficial with increasing disease progression, due to loss of beta-cell function, and with increasing insulin resistance (IR), where beta-cell function is less prominent. This work, therefore, aimed to assess the impact of such factors on the efficacy of the DPP-4 inhibitor, vildagliptin, in add-on therapy to metformin.

METHODS

A pooled analysis of 24-week efficacy data of vildagliptin 50 mg twice daily (b.i.d.) (n = 2,478) from four add-on to metformin studies was performed. Analyses for changes in hemoglobin A(1c) (HbA(1c)) were stratified according to baseline IR stage (homeostasis model assessment [Homa IR] <5, ≥5), body mass index (BMI) (<27, ≥27 to <30, ≥30 kg/m(2)), T2DM duration (0 to <1, ≥1 to <5, ≥5 years), and duration of metformin use (0 to <1, ≥1 to <5, ≥5 years). Data from patients treated with sulfonylureas (SUs) (n = 2,010) in the pooled studies are provided as reference.

RESULTS

Patients in the vildagliptin and SU groups had mean age, HbA(1c), BMI, Homa IR, duration of T2DM and metformin use of 58 years, 7.7%, 32 kg/m(2), 4.3, 5.9 years and 3.0 years, respectively. Reductions from baseline in HbA(1c) with vildagliptin were very similar across Homa IR (mean 2.8 and 8.6), BMI (mean 24.9, 28.5, and 35.3 kg/m(2)), T2DM duration (mean 0.6, 2.9, and 9.7 years), and duration of metformin use (mean 0.6, 2.6, and 7.9 years) categories, showing significant drops in HbA(1c) of approximately -0.7% (baseline 7.7%). The results in patients receiving SUs were comparable to those seen in the vildagliptin group.

CONCLUSION

Vildagliptin add-on therapy to metformin was efficacious independent of IR stage and BMI, as well as disease duration and duration of prior metformin use, indicating that, contrary to a not uncommon perception, more obese patients and patients with long-standing T2DM can benefit from treatment with the DPP-4 inhibitor, vildagliptin.

One-year safety, tolerability and efficacy of vildagliptin in patients with type 2 diabetes and moderate or severe renal impairment

AIM

Assess long-term safety and efficacy of the dipeptidlyl peptidase-4 (DPP-4) inhibitor vildagliptin in 369 patients with type 2 diabetes mellitus (T2DM) and moderate or severe renal impairment (RI).

METHODS

Double-blind, randomized, parallel-group, 52-week clinical trial comparing safety and efficacy of vildagliptin (50 mg qd, n = 216) and placebo (n = 153) added to ongoing stable antihyperglycaemic treatment, in patients with T2DM and moderate or severe (glomerular filtration rate [GFR] ≥ 30 to <50 ml/min/1.73 m(2) and < 30 ml/min/1.73 m(2) ) RI.

RESULTS

The study population comprised 122 and 89 patients with moderate RI and 94 and 64 patients with severe RI randomized to vildagliptin and placebo, respectively, with the majority of patients receiving background insulin therapy (72% and 82% for moderate and severe RI, respectively). After 1 year, the between-treatment difference in adjusted mean change in A1C was -0.4 ± 0.2% (p = 0.005) in moderate RI (baseline = 7.8%) and -0.7 ± 0.2% (p < 0.0001) in severe RI (baseline = 7.6%). In patients with moderate RI, similar proportions of patients experienced any adverse event (AE) (84 vs. 85%), any serious adverse event (SAE) (21 vs. 19%), any AE leading to discontinuation (5% vs. 6%) and death (1% vs. 0%) with vildagliptin and placebo, respectively. This was also true for patients with severe RI: AEs (85% vs. 88%), SAEs (25% vs. 25%), AEs leading to discontinuation (10% vs. 6%) and death (3% vs. 2%).

CONCLUSIONS

In patients with T2DM and moderate or severe RI, vildagliptin added to ongoing antidiabetic therapy had a safety profile similar to placebo during 1-year observation. Furthermore, relative to placebo, a clinically significant decrease in A1C was maintained throughout 1-year treatment with vildagliptin.

Efficacy and safety of vildagliptin in clinical practice-results of the PROVIL-study

AIM: To investigate efficacy and safety of vildagliptin compared to other oral antidiabetics in clinical practice in Germany.

METHODS: In this prospective, open, observational study, patients with type 2 diabetes mellitus (T2DM) previously on oral monotherapy were selected by their treating physician to receive either vildagliptin add-on to metformin (cohort 1), vildagliptin + metformin single-pill combination (SPC) (cohort 2) or another dual combination therapy with oral antidiabetic drugs (OADs) (cohort 3). According to routine clinical practice, interim examinations occurred every 3 mo: at baseline, after approximately 3 mo and after approximately 6 mo. Parameters documented in the study included demographic and diagnostic data, history of T2DM, data on diabetes control, vital signs, relevant prior and concomitant medication and disease history. Efficacy was assessed by changes in HbA1c and fasting plasma glucose (FPG) 3 mo and 6 mo after initiation of dual combination therapy. Safety was assessed by adverse event reporting and measurement of specific laboratory values (serum creatinine, total bilirubin, alanine aminotransferase, aspartate aminotransferase, creatine kinase).

RESULTS: Between October 2009 and January 2011, a total of 3881 patients were enrolled in this study. Since 47 patients were withdrawn due to protocol violations, 3834 patients were included in the statistical analysis. There were no relevant differences between the three cohorts concerning age, body weight and body mass index. Average diabetes duration was approximately 6 years and mean HbA1c was between 7.6% and 7.9% at baseline. Antidiabetic treatment was recorded in 3648 patients. Patients were treated with vildagliptin add-on to metformin (n = 603), vildagliptin + metformin (SPC) (n = 2198), and other oral OADs including combinations of metformin with sulfonylurea (n = 370), with glitazones (n = 123), other dipeptidyl peptidase-4 inhibitors (n = 99). After 6 mo of treatment, the absolute decrease in HbA1c (mean ± SE) was significantly more pronounced in patients receiving vildagliptin add-on to metformin (-0.9% ± 0.04%) and vildagliptin + metformin (SPC) (-0.9% ± 0.03%) than in patients receiving other OADs (-0.6% ± 0.04%; P < 0.0001). In addition, significant cohort differences were observed for the improvement in FPG after 6 mo treatment (vildagliptin add-on to metformin: -291 mg/L ± 18.3 mg/L; vildagliptin +metformin (SPC): -305 mg/L ± 9.6 mg/L; other antidiabetic drugs: -209 mg/L ± 14.0 mg/L for (P < 0.0001). Moderate decreases in body weight (absolute difference between last control and baseline: mean ± SE) were observed for patients in all cohorts (vildagliptin add-on to metformin: -1.4 kg ± 0.17 kg; vildagliptin + metformin (SPC): -1.7 kg ± 0.09 kg; other OADs: -0.8 kg ± 0.13 kg). No significant differences in adverse events (AEs) and other safety measures were observed between the cohorts. When performing an additional analysis by age (patients < 65 years vs patients ≥ 65 years), there was no relevant difference in the most common AEs between the two age groups and the AE profile was similar to that of the overall patient population.

CONCLUSION: Clinical practice confirms that vildagliptin is an effective and well-tolerated treatment in combination with metformin in T2DM patients.

Glycaemic efficacy of glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors as add-on therapy to metformin in subjects with type 2 diabetes-a review and meta analysis

AIMS

During recent years, two strategies of incretin-based therapy [glucagon-like peptide-1 (GLP-1) receptor agonism and dipeptidyl peptidase-4 (DPP-4) inhibition] have entered the market for pharmacological management of type 2 diabetes. A main indication for this therapy is as add-on to on-going metformin therapy in subjects with type 2 diabetes who have insufficient glycaemic control with metformin alone. The aim of this study was to compare improvements in glycaemic control and changes in body weight, as well as adverse events, in comparable studies with incretin-based therapy as add-on to metformin.

METHODS

Studies having a duration of 16-30 weeks were identified from PubMed.

RESULTS

A total of 27 study groups in 21 studies fulfilled the criteria of examining incretin-based therapy as add-on to metformin at clinically recommended doses in patients with type 2 diabetes for 16-30 weeks; 7 of these used a short-acting GLP-1 receptor agonist (exenatide BID), 7 used longer acting GLP-1 receptor agonists (liraglutide or exenatide LAR), whereas 14 studies examined DPP-4 inhibitors. In all studies, incretin-based therapy reduced HbA1c concentrations. The reduction in HbA1c was significantly greater in study groups with long-acting GLP-1 receptor agonists than with the other two groups (both p < 0.001), whereas there were no differences between exenatide BID and DPP-4 inhibitors. Across all study groups, there was a negative linear correlation between baseline HbA1c and change in HbA1c (r = -0.70; p < 0.001). Fasting glucose also fell significantly more in study groups given liraglutide or exenatide LAR than in those given exenatide BID or DPP-4 inhibitors (both p < 0.001). Furthermore, body weight was reduced by a similar extent in the two groups with GLP-1 receptor agonists and was not significantly altered in the groups with DPP-4 inhibitors. Lipids, blood pressure and heart rate were not reported consistently, which did not allow general conclusions. Adverse events were rare, apart from increased incidence of nausea and vomiting with GLP-1 receptor agonists.

CONCLUSION

Incretin-based therapy efficiently improves glycaemia when added to metformin in patients with type 2 diabetes, and within 16-30 weeks there is a more pronounced reduction in HbA1c with long-acting GLP-1 receptor agonists (liraglutide and exenatide LAR) than with exenatide BID and DPP-4 inhibitors, although the magnitude of the effect is dependent on the baseline values. Both strategies appear to be associated with a very low risk of adverse events, including hypoglycaemia. Finally, the injectable GLP-1 receptor agonists also reduce body weight (whereas the DPP-4 inhibitors are weight neutral) but are also associated with a greater incidence of gastrointestinal side effects and a tendency to increase heart rate.

Evidence to support the use of vildagliptin monotherapy in the treatment of type 2 diabetes mellitus

The efficacy and safety of the dipeptidyl peptidase-4 inhibitor, vildagliptin, as monotherapy have been widely confirmed in a large body of clinical studies of up to 2 years’ duration in various populations with type 2 diabetes mellitus. This paper reviews the data supporting the use of vildagliptin in monotherapy. Consideration based on baseline glycated hemoglobin levels and age is given to patient segments where metformin is not appropriate. In addition, although prediabetes is not an indication, this manuscript briefly reviews some of the existing data showing that the mechanisms at work in diabetic populations are active in patients currently classified as prediabetic, with impaired glucose tolerance or impaired fasting glucose. Finally, the rationale for vildagliptin dosing frequency in monotherapy is discussed. In summary, this review aims to define where in community practice the use of vildagliptin as monotherapy is most desirable, focusing on segments of the population with type 2 diabetes mellitus that might receive the greatest benefit from vildagliptin in the management of their disease.

A review of gliptins in 2011

INTRODUCTION

Dipeptidylpeptidase-4 (DPP-4) inhibitors offer new options for the management of type 2 diabetes (T2DM).

AREAS COVERED

This paper is an updated review, providing an analysis of both the similarities and the differences between the various compounds known as gliptins, currently used in the clinic (sitagliptin, vildagliptin, saxagliptin, alogliptin and linagliptin). This paper discusses the pharmacokinetic and pharmacodynamic characteristics of gliptins; both the efficacy and safety profiles of gliptins in clinical trials (compared with classical glucose-lowering agents), given as monotherapy or in combination, including in special populations; the positioning of DPP-4 inhibitors in the management of T2DM in recent guidelines; and various unanswered questions and perspectives.

EXPERT OPINION

The role of DPP-4 inhibitors in the therapeutic armamentarium of T2DM is evolving, as their potential strengths and weaknesses become better defined. Future critical issues may include the durability of glucose control, resulting from better β-cell protection, positive effects on cardiovascular outcomes and long-term safety issues.

Safety and efficacy of vildagliptin versus placebo in patients with type 2 diabetes and moderate or severe renal impairment: a prospective 24-week randomized placebo-controlled trial

AIM

Assess safety/tolerability and efficacy of the DPP-4 inhibitor vildagliptin in 515 patients with type 2 diabetes mellitus (T2DM) and moderate or severe renal impairment (RI).

METHODS

Double-blind, randomized, parallel-group, placebo-controlled, 24-week clinical trial assessing safety and efficacy of vildagliptin (50 mg qd) added to current antidiabetic therapy, in patients with T2DM and moderate or severe RI (GFR ≥ 30 to <50 or <30 ml/min/1.73 m(2) ).

RESULTS

The study population comprised of 165 and 129 patients with moderate RI and 124 and 97 patients with severe RI randomized to vildagliptin and placebo, respectively, with most patients receiving background insulin therapy (68 and 81% for moderate and severe RI, respectively). After 24 weeks, the between-treatment difference in the adjusted mean change in A1C was -0.5 ± 0.1% (p < 0.0001) in moderate RI (baseline A1C = 7.9%) and -0.6 ± 0.1% (p < 0.0001) in severe RI (baseline A1C = 7.7%). In patients with moderate RI, similar proportions of those receiving vildagliptin or placebo experienced any AE (68 vs. 73%), any SAE (9 vs. 9%), any AE leading to discontinuation (3 vs. 5%) or death (1 vs. 1%). This was also true for patients with severe RI: AEs (73 vs. 74%), SAEs (19 vs. 21%), AEs leading to discontinuation (9 vs. 6%) and death (2 vs. 4%).

CONCLUSIONS

In this 24-week study of 515 patients with T2DM and moderate or severe RI, vildagliptin added to ongoing antidiabetic therapy had a safety profile similar to placebo. Further, relative to placebo, vildagliptin elicited a statistically and clinically significant decrease in A1C in patients with moderate or severe RI.

Effectiveness of adding vildagliptin to the treatment of diabetic patients nonresponsive to the combination of metformin and a sulphonylurea

OBJECTIVE: To evaluate the effectiveness of adding vildagliptin to the treatment of patients with inadequately controlled type 2 diabetes mellitus (T2DM) treated with a combination of metformin and a sulphonylurea. SUBJECTS AND METHODS: 37 T2DM patients with HbA1c ranging from 7.7% to 12.4% (mean of 9.30 ± 1.38), despite the use of metformin in combination with a sulphonylurea, were additionally treated with vildagliptin (100 mg/day) for at least 6 months. RESULTS: During triple oral therapy (TOT) HbA1c levels < 7% were achieved in 11 patients (29.7%), whereas levels of fasting plasma glucose (FPG) < 120 mg/dL were observed in 12 patients (32.4%). Both findings were observed in 10 patients (27.0%). Compared to nonresponsive subjects, lower mean baseline HbA1c and FPG levels were seen in responsive patients, but the difference was only statistically significant for fasting plasma glucose (FPG). Moreover, there was considerable overlap between the two groups. CONLUSION: Our preliminary results suggest that TOT with metformin, a sulphonylurea and vildagliptin may be useful for some T2DM patients nonresponsive to combination therapy with metformin and sulphonylurea.