Efficacy and safety of vildagliptin and voglibose in Japanese patients with type 2 diabetes: a 12-week, randomized, double-blind, active-controlled study

Efficacy and Safety of Metformin Versus the Other Oral Antidiabetic Drugs in Japanese Type 2 Diabetes Patients: A Network Meta-analysis

INTRODUCTION

Although metformin is recommended as a first-line treatment for patients with type 2 diabetes (T2D) in Western countries, no specific treatment is recommended in Japan, and various agents are used. Metformin has long been used at low doses in Japan, and information regarding its effect at the maximum maintenance dose is lacking. Here, we compared the efficacy and safety of metformin at 1500 mg/day with those of the other oral anti-diabetic drugs (OADs) approved in Japan.

METHODS

Randomized controlled trials comparing a change in hemoglobin A1c (HbA1c) from baseline at 12 weeks or later (ΔHbA1c) among OADs (including placebo) as a first-line treatment in adult patients with T2D were selected by systematic review with comprehensive searching of CENTRAL, MEDLINE, Ichushi Web, and EMBASE and manual searching of clinical trial registries. The ΔHbA1c and incidence of hypoglycemia were compared among OAD treatments using Bayesian network meta-analysis (NMA). The relative risk (RR) of the incidence of hypoglycemia was determined relative to that of placebo.

RESULTS

Forty-six randomized controlled trials were identified in the systematic review, and 37 studies, comprising 38 different types of treatments, including placebos, were selected for the NMA of ΔHbA1c. Compared with metformin 1500 mg/day, 20 OAD treatments were significantly less effective in reducing HbA1c from baseline (differences from metformin 1500 mg/day: 0.40-0.96%). Two treatments (glimepiride 2 mg/day and pioglitazone 45 mg/day) showed greater mean reductions in HbA1c from baseline than metformin 1500 mg/day (- 0.38% and - 0.03%), although these differences were not significant. Regarding the incidence of hypoglycemia, only pioglitazone 30 mg/day among 31 treatments showed a lower RR (< - 0.01), whereas 23 treatments showed a significantly higher RR (1.02-66.71) than metformin 1500 mg/day.

CONCLUSION

The NMA suggested a preferable efficacy and safety profile of metformin 1500 mg/day compared with the other OADs approved in Japan.

Hypoglycemia possibly caused by CYP2C9-mediated drug interaction in combination with bucolome: a case report

Background

Bucolome is a non-steroidal anti-inflammatory drug and uricosuric agent, currently used only in Japan. It is known to induce drug interactions by inhibiting cytochrome P450 (CYP) 2C9. It is often used to enhance the anticoagulant effect of warfarin by utilizing its drug interactions. There are only a few reports on drug interactions of bucolome and the mechanism remain poorly understood.

Case presentation

An 81-year-old woman with a history of type 2 diabetes mellitus was taking glimepiride 2 mg/day and voglibose 0.6 mg/day. After hospitalization, the patient underwent surgical aortic valve replacement surgery (day 0). Glimepiride and voglibose were resumed on the second postoperative day (day 2), and warfarin was started to prevent thromboembolism. Since the prothrombin time-international normalized ratio on day 9 was low at 1.24, 300 mg/day of bucolome was added to enhance the effect of warfarin. A gradual decrease in blood glucose levels was observed from the day after bucolome administration was initiated. Hypoglycemia in the 56–57 mg/dL range occurred before lunch and dinner on the 6th day (day 14) of bucolome administration, due to which voglibose was discontinued. Hypoglycemia below 70 mg/dL was not observed thereafter, and the general condition of the patient was stable.

Conclusions

Based on the clinical course and literature review, we believe that hypoglycemia in the present case was due to a drug interaction, caused by inhibition of CYP2C9 by bucolome and competitive inhibition of CYP2C9 by warfarin, which affected the pharmacokinetics of glimepiride. The possibility of hypoglycemia due to drug interactions should be considered by physicians, when bucolome is included to enhance the effect of warfarin, in patients taking glimepiride.

The impact of vildagliptin on the daily glucose profile and coronary plaque stability in impaired glucose tolerance patients with coronary artery disease: VOGUE-A multicenter randomized controlled trial

Background

The impact of reduction in glycemic excursion on coronary plaques remains unknown. This study aimed to elucidate whether a dipeptidyl peptidase 4 inhibitor could reduce the glycemic excursion and stabilize the coronary plaques compared with conventional management in coronary artery disease (CAD) patients with impaired glucose tolerance (IGT).

Methods

This was a multicenter, randomized controlled trial including CAD patients with IGT under lipid-lowering therapy receiving either vildagliptin (50 mg once a day) or no medication (control group) regarding glycemic treatment. The primary endpoint was changes in the minimum fibrous cap thickness and lipid arc in non-significant native coronary plaques detected by optical coherence tomography at 6 months after intervention. Glycemic variability expressed as the mean amplitude of glycemic excursion (MAGE) measured with a continuous glucose monitoring system was evaluated before and 6 months after intervention.

Results

A total of 20 participants with 47 lesions were allocated to either the vildagliptin group (10 participants, 22 lesions) or the control group (10 participants, 25 lesions). The adjusted difference of mean changes between the groups was − 18.8 mg/dl (95% confidence interval, − 30.8 to − 6.8) (p = 0.0064) for the MAGE (vildagliptin, − 20.1 ± 18.0 mg/dl vs. control, 2.6 ± 12.7 mg/dl), − 22.8° (− 40.6° to − 5.1°) (p = 0.0012) for the mean lipid arc (vildagliptin, − 9.0° ± 25.5° vs. control, 15.8° ± 16.8°), and 42.7 μm (15.3 to 70.1 μm) (p = 0.0022) for the minimum fibrous cap thickness (vildagliptin, 35.7 ± 50.8 μm vs. control, − 15.1 ± 25.2 μm).

Conclusions

Vildagliptin could reduce the MAGE at 6 months and may be associated with the decreased lipid arc and increased minimum FCT of the coronary plaques in CAD patients with IGT as compared with the control group. These findings may represent its potential stabilization effect on coronary plaques, which are characteristic in this patient subset.

Trial registration Registered in the UMIN clinical trial registry (UMIN000008620), Name of the registry: VOGUE trial, Date of registration: Aug 6, 2012, URL: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000010058

Specificity of transaminase activities in the prediction of drug-induced hepatotoxicity

The activities of the transaminases (aminotransferases) alanine aminotransferase and aspartate aminotransferase in the blood (serum or plasma) are widely used as sensitive markers of possible tissue damage and, in particular for liver toxicity. On the other hand, an increase in transaminase activities is not always accompanied by findings suggestive of hepatotoxicity. Transaminases are some of the key enzymes in the gluconeogenesis and glycolysis pathways and exist in many organs and tissues which have high activities of the gluconeogenesis and glycolysis. The activities of transaminases are altered not only in the liver but also in other organs by modification of gluconeogenesis by nutritional or hormonal factors and this phenomenon leads to alteration of transaminase activity in the blood. Drugs, which are considered to directly or secondarily modify gluconeogenesis through lowering blood glucose levels or activating lipid metabolism, such as α-glucosidase inhibitors and fibrates, slightly increase transaminase activities in the blood but there is little evidence that the phenomenon is related to drug-induced liver injury (DILI). This type of elevations can be called pharmacology-related elevation. The pharmacology-related elevation of transaminase activities sometimes makes it difficult to assess precisely the potential hepatotoxicity of new investigational drugs. Considering the characteristic of transaminases, concomitant use of new biomarkers more specific to hepatic injury is needed in the assessment of DILI both in non-clinical and clinical studies. In this review, we will discuss the specificity of transaminases to DILI and future perspectives for transaminases in the estimation of risk of DILI.

Comparisons between dipeptidyl peptidase-4 inhibitors and other classes of hypoglycemic drugs using two distinct biomarkers of pancreatic beta-cell function: A meta-analysis

Background and objective

Dipeptidyl peptidase-4 (DPP-4) inhibitors have been suggested to have pancreatic beta-cell preserving effect according to studies using homeostatic model of assessment for beta-cell function (HOMA-β). However, whether HOMA-β is a suitable biomarker for comparisons between hypoglycemic drugs with different mechanisms of action remains unclear. Therefore, we conducted a meta-analysis to compare the effects of DPP-4 inhibitors and other classes of hypoglycemic drugs on HOMA-β and proinsulin-to-insulin ratio (PIR).

Methods

We searched MEDLINE, CENTRAL, and Ichushi-web for the period of 1966 to May 2020. We collected randomized, controlled clinical trials in patients with type 2 diabetes mellitus comparing DPP-4 inhibitors and other classes of hypoglycemic agents [α-glucosidase inhibitors (α-GIs), glucagon-like peptide-1 (GLP-1) analogues, metformin, sodium-glucose cotransporter 2 (SGLT2) inhibitors, sulfonylureas, or thiazolidinediones]. Weighted mean differences and 95% confidence intervals of changes in HOMA-β or PIR during study periods were calculated for pairwise comparisons.

Results

Thirty-seven and 21 relevant trials were retrieved for comparisons of HOMA-β and PIR, respectively. HOMA-β and PIR consistently showed superiority of DPP-4 inhibitors compared with α-GIs. Both biomarkers consistently supported inferiority of DPP-4 inhibitors compared with GLP-1 analogues. However, PIR showed inferiority of DPP-4 inhibitors compared with metformin, and superiority compared with SGLT2 inhibitors, whereas HOMA-β showed no significant differences between DPP-4 inhibitors and the two other agents.

Conclusion

DPP-4 inhibitors appear to be superior to α-GIs but inferior to GLP-1 analogues in preservation of beta-cell function assessed by either HOMA-β or PIR. DPP-4 inhibitors seem to be superior to SGLT2 inhibitors but inferior to metformin on islet function assessed only by PIR. Because HOMA-β and PIR may indicate different aspects of beta-cell function, results of beta-cell function preserving effects of hypoglycemic agents should be interpreted with caution.

Vildagliptin Versus α-Glucosidase Inhibitor as Add-On to Metformin for Type 2 Diabetes: Subgroup Analysis of the China Prospective Diabetes Study

INTRODUCTION

The effect of dipeptidyl peptidase-4 (DDP-4) inhibitors versus α-glucosidase inhibitors (AGIs) on the treatment of type 2 diabetes mellitus (T2DM) in a real-world setting is unknown. The aim of this real-world study was to compare the glucose-lowering effect and tolerability of vildagliptin as add-on to metformin monotherapy (VM) and AGI as add-on to metformin monotherapy (AM) in Chinese patients with T2DM.

METHODS

This was a subgroup analysis of the China Prospective Diabetes Study, a post-marketing, prospective, observational, real-world study conducted at 52 centers in China. T2DM patients with inadequate glycemic control on metformin monotherapy who received VM or AM were included. The composite primary endpoint was glycemic control (hemoglobin A1c [HbA1c] < 7%) after 12 months in the absence of tolerability events (hypoglycemia, weight gain ≥ 3%, or gastrointestinal events leading to treatment discontinuation). Propensity score matching (PSM) was used to balance the two groups.

RESULTS

The success rates of the composite endpoint were higher in the VM group (n = 604/159 before/after PSM) than in the AM group (n = 159/157 before/after PSM), but the difference was not statistically significant (before PSM: 53.0 vs. 46.5%, P = 0.148; after PSM: 56.7 vs. 45.9%, P = 0.055). The glycemic control rate and HbA1c reduction were similar between groups at 3, 6, and 12 months. Compared with the AM group, the VM group had lower risks of any tolerability event (relative risk [RR] 0.53, 95% confidence interval [CI] 0.33-0.83, P = 0.006), of any adverse event (AE) (RR 0.64, 95% CI 0.41-1.00, P = 0.049), and of any serious AE (RR  0.45, 95% CI 0.25-0.81, P = 0.007).

CONCLUSION

The results of this real-world study suggest that vildagliptin as add-on to metformin monotherapy had a similar glucose-lowering effect to AGI as add-on to metformin monotherapy, but with better safety.

Long-Term Efficacy and Safety of Linagliptin in a Japanese Population with Type 2 Diabetes Aged ≥ 60 Years Treated with Basal Insulin: A Randomised Trial

INTRODUCTION

An estimated 4.3 million people aged ≥ 65 years with diabetes live in Japan. We evaluated the efficacy and safety of linagliptin in older Japanese patients with poorly controlled type 2 diabetes (T2DM).

METHODS

In this phase 4, randomised, placebo-controlled national study (part of a global study) conducted in Japan over a period of 52 weeks, 102 patients on stable treatment with basal insulin ± metformin/alpha-glucosidase inhibitors were randomised (1:1) to receive linagliptin 5 mg qd or placebo. The primary end point was the change in glycated haemoglobin (HbA1c) after 24 weeks of treatment, with additional analyses at 52 weeks.

RESULTS

Mean age and HbA1c of the study population were 71 years and 8.1%, respectively. Approximately two-thirds of participants were aged ≥ 70 years, two-thirds had macrovascular complications, approximately half had a baseline estimated glomerular filtration rate < 60 ml/min/1.73 m², and two-thirds had a time since diagnosis of diabetes > 10 years. Significant HbA1c reductions with linagliptin vs. placebo were observed at 24 weeks, - 0.71% (95% CI - 0.96, - 0.45, p < 0.0001), and maintained at 52 weeks, - 0.58% (95% CI - 0.82, - 0.34, p < 0.0001). Linagliptin improved the chances of achieving a categorical HbA1c target (< 8.0% and < 7.0%) at 24 and 52 weeks in patients who were not at their respective target at the beginning of the study. Addition of linagliptin to insulin was associated with a numerical increase in the risk of any hypoglycaemia, but not in the risk of clinically significant hypoglycaemia, severe hypoglycaemia or recurring hypoglycaemia.

CONCLUSION

Linagliptin was effective in improving glucose control in Japanese patients aged ≥ 60 years with T2DM on stable glucose-lowering therapy with basal insulin. Linagliptin was well tolerated and no new safety concerns were raised. The results presented here are highly consistent with the results from the global study, which was conducted over a 24-week period.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02240680.

FUNDING

Boehringer Ingelheim and Eli Lilly and Company Diabetes Alliance.

Head-to-Head Comparison of the Hypoglycemic Efficacy and Safety Between Dipeptidyl Peptidase-4 Inhibitors and α-Glucosidase Inhibitors in Patients With Type 2 Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trials

Background: The α-glucosidase inhibitors (AGIs) are commonly prescribed in Asian patients with type 2 diabetes mellitus (T2DM), but with a high incidence of gastrointestinal side effects. This study was aimed to compare the efficacy and safety of dipeptidyl peptidase-4 (DPP4) inhibitors and AGIs in T2DM patients in a meta-analysis.

Methods: Randomized controlled trials were identified via systematic search of PubMed, Embase, and Cochrane’s Library databases from inception to February, 2019. Meta-analyses were performed via a random or a fixed effect model according to the heterogeneity.

Results: Eighteen studies with a total of 4,051 patients with T2DM were included. The DPP4 inhibitors were associated with lower reduction of glycosylated hemoglobin (HbA1c) as compared with AGIs [weighed mean difference (WMD): −0.37%, p < 0.001]. Subgroup analyses indicated that the benefit of DPP4 inhibitors as compared with AGIs on HbA1c were independent of study design, scale, baseline HbA1c, with or without concurrent medications, or follow-up durations. Moreover, compared to AGIs, DPP4 inhibitors was associated with lower reductions of fasting blood glucose (WMD: −0.53 mmol/L, P < 0.001) and postprandial glucose at 2h (WMD: −0.60 mmol/L, P = 0.04), moderately increased body weight (WMD: 0.34 kg, P = 0.02), and decreased risk of gastrointestinal adverse events [risk ratio (RR): 0.48, P < 0.001], but unaffected risk of symptomatic hypoglycemia (RR: 0.96, P = 0.90).

Conclusions: The DPP4 inhibitors are superior to AGIs in T2DM patients for better glycemic control and lower risks of gastrointestinal side effects.

Meta-analysis and critical review on the efficacy and safety of alpha-glucosidase inhibitors in Asian and non-Asian populations

AIMS/INTRODUCTION

To evaluate the efficacy and safety of alpha-glucosidase inhibitors (AGI) in Asian and non-Asian type 2 diabetes patients.

MATERIALS AND METHODS

Studies were identified through a literature search of MEDLINE, EMBASE and other databases until December 2016. All statistical analyses were carried out in Review Manager statistical software by computing the weighted mean difference or odds ratio and 95% confidence interval.

RESULTS

A total of 67 studies were included. AGI vs placebo: compared with the placebo, AGI treatment led to a greater decrease in hemoglobin A1c (HbA1c), fasting plasma glucose and postprandial plasma glucose. No significant difference was observed in HbA1c change, fasting plasma glucose change, postprandial plasma glucose change or incidence of hypoglycemia between Asian and non-Asian patients. AGI vs active controls: in Asian patients, AGI treatment showed a lower reduction in HbA1c compared with dipeptidyl peptidase-4 inhibitors and sulfonylurea. In non-Asian patients, AGI treatment showed a lower reduction in HbA1c compared with thiazolidinedione. No significant difference was observed in HbA1c change and bodyweight change when comparing AGI with other oral hypoglycemic agents between Asian and non-Asian patients.

CONCLUSIONS

The effects of AGI treatment on glycemic control and bodyweight reduction were superior to the placebo without an increased incidence of hypoglycemia, but with an increased incidence of gastrointestinal discomforts. The hypoglycemic effects of AGI were comparable between Asian and non-Asian patients.

Gastrointestinal Adverse Events of Dipeptidyl Peptidase 4 Inhibitors in Type 2 Diabetes: A Systematic Review and Network Meta-analysis

PURPOSE

The purpose of this study was to systematically evaluate the effect of dipeptidyl peptidase 4 inhibitors on gastrointestinal adverse events in patients with type 2 diabetes.

METHODS

MEDLINE, Embase, the Cochrane Library, and ClinicalTrials.gov were searched from inception through April 28, 2016. Randomized controlled trials that compared dipeptidyl peptidase 4 inhibitor-based therapies with placebo and other hypoglycemic agents in type 2 diabetes were included. The duration of studies was at least 4 weeks.

FINDINGS

A total of 165 randomized controlled trials and 122,072 patients were included in the study. Dipeptidyl peptidase 4 inhibitors did not increase the incidence of gastrointestinal adverse events after the treatment with alogliptin (odds ratio [OR] = 0.83; 95% CI, 0.59-1.15), linagliptin (OR = 1.11; 95% CI, 0.92-1.35), saxagliptin (OR = 0.96; 95% CI, 0.80-1.15), sitagliptin (OR = 0.95; 95% CI, 0.64-1.14), teneligliptin (OR = 1.50; 95% CI, 0.81-2.77), and vildagliptin (OR = 0.80; 95% CI, 0.63-1.01) compared with placebo. Compared with glucagon-like peptide 1 receptor agonists, dipeptidyl peptidase 4 inhibitors significantly decreased the incidence of gastrointestinal adverse events with alogliptin (OR = 0.26; 95% CI, 0.15-0.44), linagliptin (OR = 0.43; 95% CI, 0.25-0.74), saxagliptin (OR = 0.28; 95% CI, 0.17-0.46), sitagliptin (OR = 0.24; 95% CI, 0.17-0.35), and vildagliptin (OR = 0.27; 95% CI, 0.18-0.41). Dipeptidyl peptidase 4 inhibitors were not associated with an increased risk of gastrointestinal adverse events relative to metformin and α-glucosidase inhibitors, respectively.

IMPLICATIONS

The network meta-analysis found that compared with glucagon-like peptide 1 receptor agonists, metformin, and α-glucosidase inhibitor, dipeptidyl peptidase 4 inhibitors are associated with a lower incidence of gastrointestinal adverse events.

Predictors of efficacy of GLP-1 agonists and DPP-4 inhibitors: A systematic review

AIMS

To identify the determinants of efficacy of glucagon-like peptide-1 receptor agonists (GLP-1A) and dipeptidyl peptidase-4 inhibitors (DPP-4I).

METHODS

MEDLINE and EMBASE were searched between 01/01/2011 and 15/08/2014 for randomized controlled trials of 12-52weeks' duration, which reported the change in glycated hemoglobin (HbA1c) from baseline as the primary end point, and reported data about predictors of efficacy of incretins.

RESULTS

Among 4172 studies found, 77 studies reported data on baseline HbA1c, age, sex, ethnicity, body mass index (BMI), and history of diabetes in relation to change in HbA1c. For DPP-4I, 37 out of 47 studies reported a greater decrease in HbA1c among patients with higher baseline HbA1c. Most DPP-4I studies reported no variation in efficacy in regard to demographic characteristics or BMI. Among 17 studies reporting on GLP-1A, baseline higher HbA1c was reported as predictive of a greater response in 7 out of 9 studies; 13 studies reported data about other factors, without consistent findings.

CONCLUSIONS

Current evidence suggests that higher baseline HbA1c is associated with a greater efficacy of both DPP-4I and GLP-1A therapies in lowering HbA1c. The roles of other potential predictors are less consistent across studies and require further investigation.

Alpha-glucosidase inhibitors and hepatotoxicity in type 2 diabetes: a systematic review and meta-analysis

Alpha-glucosidase inhibitors (AGIs) was reported to be associated with several rare adverse hepatic events, but with inconsistent results. We aimed to investigate the risk of hepatotoxicity associated with the use of AGIs in patients with type 2 diabetes mellitus (T2DM), and performed a systematic review and meta-analysis. Fourteen studies (n = 2881) were eligible, all of which were RCTs. Meta-analysis of data regarding elevation of more than 3-fold the upper limit of normal (ULN) of AST and ALT showed statistically significant differences between AGIs treatment versus control (OR 6.86, 95% CI 2.50 to 18.80; OR 6.48, 95% CI 2.40 to 17.49). Subgroup analyses of elevation of more than 1.8-fold ULN of AST and ALT by dose of AGIs showed differential effects on AST and ALT (AST: OR 0.38 vs 7.31, interaction P = 0.003; ALT: OR 0.32 vs 4.55, interaction p = 0.02). Meta-analysis showed that AGIs might increase the risk of hepatotoxicity, and higher dose appeared to be associated with higher risk of hepatotoxicity. However, the evidence is limited with surrogate measures (i.e. ALT and AST), and no clinically important adverse events were observed.

Dipeptidyl peptidase-4 inhibitors and fracture risk: an updated meta-analysis of randomized clinical trials

Data on the effects of dipeptidyl peptidase-4 (DPP-4) inhibitors on fracture risk are conflicting. Here, we performed a systematic review and meta-analysis of randomized controlled trials (RCTs) assessing the effects of DPP-4 inhibitors. Electronic databases were searched for relevant published articles, and unpublished studies presented at ClinicalTrials.gov were searched for relevant clinical data. Eligible studies included prospective randomized trials evaluating DPP-4 inhibitors versus placebo or other anti-diabetic medications in patients with type 2 diabetes. Study quality was determined using Jadad scores. Statistical analyses were performed to calculate the risk ratios (RRs) and 95% confidence intervals (CIs) using fixed-effects models. There were 62 eligible RCTs with 62,206 participants, including 33,452 patients treated with DPP-4 inhibitors. The number of fractures was 364 in the exposed group and 358 in the control group. The overall risk of fracture did not differ between patients exposed to DPP-4 inhibitors and controls (RR, 0.95; 95% CI, 0.83–1.10; P = 0.50). The results were consistent across subgroups defined by type of DPP-4 inhibitor, type of control, and length of follow-up. The study showed that DPP-4 inhibitor use does not modify the risk of bone fracture compared with placebo or other anti-diabetic medications in patients with type 2 diabetes.

Pharmacological Actions of Glucagon-Like Peptide-1, Gastric Inhibitory Polypeptide, and Glucagon

Glucagon family of peptide hormones is a group of structurally related brain-gut peptides that exert their pleiotropic actions through interactions with unique members of class B1 G protein-coupled receptors (GPCRs). They are key regulators of hormonal homeostasis and are important drug targets for metabolic disorders such as type-2 diabetes mellitus (T2DM), obesity, and dysregulations of the nervous systems such as migraine, anxiety, depression, neurodegeneration, psychiatric disorders, and cardiovascular diseases. The current review aims to provide a detailed overview of the current understanding of the pharmacological actions and therapeutic advances of three members within this family including glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP), and glucagon.

Systematic review and meta-analysis of vildagliptin for treatment of type 2 diabetes

This systematic review and meta-analysis provides an update on the efficacy and safety of vildagliptin for treatment of type 2 diabetes mellitus (T2DM). We searched MEDLINE, COCHRANE, EMBASE and the drug manufacturer's website for randomised controlled trials of vildagliptin in patients with T2DM. Sixty-nine studies (28,006 patients) were included in the meta-analysis. Compared with placebo vildagliptin reduced HbA1c (weighted mean difference WMD -0.69 %; 95 % CI -0.83 to -0.56 %; I (2) = 82 %), and it was as effective as other antidiabetic agents (WMD -0.01 %; 95 % CI -0.16 to 0.14 %; I (2) = 93 %), without increasing the risk for hypoglycemia (OR 0.83; 95 % CI 0.59 to 1.16; I (2) = 0 % vs. placebo, and OR 0.19; 95 % CI 0.15 to 0.24; I (2) = 78 % versus active comparators). However, it was associated with an increase in the incidence of arthralgia compared with other comparators (OR 1.23; 95 % CI 1.02 to 1.48; I (2) = 0 %). On the contrary, vildagliptin did not increase the incidence of pancreatitis (OR 0.97; 95 % CI 0.37 to 2.53; I (2) = 0 %), serious adverse events (OR 0.98; 95 % CI 0.88 to 1.09; I (2) = 0 %) or death (OR 1.10, 95 % CI 0.75 to 1.61; I (2) = 0 %). Finally, odds ratio (OR) for heart failure, and overall cardiovascular and cerebrovascular events was 0.77 (95 % CI 0.46 to 1.30; I (2) = 0 %) and 0.91 (95 % CI 0.73 to 1.14; I (2) = 0 %), respectively. Vildagliptin is an effective and safe therapeutic option for patients with T2DM, both as monotherapy and as add-on treatment.

Comparative studies of dipeptidyl peptidase 4 inhibitor vs sulphonylurea among Muslim Type 2 diabetes patients who fast in the month of Ramadan: A systematic review and meta-analysis

AIM

To systematically review the literature to compare the use of DPP4 inhibitors vs sulphonylurea in type 2 diabetic Muslim patients who fast in Ramadan, with regards to its safety, tolerability, glycemic control, and body weight changes.

METHODS

All English-language medical literature published from inception till October 2014 which met the inclusion criteria were reviewed and analyzed.

RESULTS

A total of nine papers were included, reviewed and analyzed. The total sample size was 4276 patients. All studies used either of the two DPP4 inhibitors - Vildagliptin or Sitagliptin, vs sulphonylurea or meglitinides. Patients receiving DPP4 inhibitors were less likely to develop symptomatic hypoglycemia (risk ratio 0.46; 95% CI, 0.30-0.70), confirmed hypoglycemia (risk ratio 0.36; 95% CI, 0.21-0.64) and severe hypoglycemia (risk ratio 0.22; 95% CI, 0.10-0.53) compared with patients on sulphonylureas. There was no statistically significant difference in HbA1C changes comparing Vildagliptin and sulphonylurea.

CONCLUSION

DPP4 inhibitor is a safer alternative to sulphonylurea in Muslim patients with type 2 diabetes mellitus who fast during the month of Ramadan as it is associated with lower risk of symptomatic, confirmed and severe hypoglycemia, with efficacy comparable to sulphonylurea.

Association between therapy with dipeptidyl peptidase-4 (DPP-4) inhibitors and risk of ileus: a cohort study

Background

Three cases of ileus have been published among dipeptidyl peptidase-4 (DPP-4) inhibitor users in Japan. The purpose of this study was to estimate and compare incidence rates of ileus among alogliptin users and users of other DPP-4 inhibitors, glucagon-like peptide 1 (GLP-1) receptor agonists, and voglibose.

Methods

We used the Medical Data Vision database in Japan to conduct a retrospective cohort study among type 2 diabetes mellitus (T2DM) patients who were new users of alogliptin, other DPP-4 inhibitors, GLP-1 receptor agonists, or voglibose between 1 April 2010 and 30 April 2014. The primary outcome was an incident diagnosis of ileus. Kaplan-Meier survival curves were used to estimate ileus events over time. Adjusted Poisson regression models were used to estimate incidence rate ratios (IRR) for ileus and 95 % confidence intervals (CI) by comparing alogliptin users to users of the other study drugs.

Results

We identified 82,386 patients with T2DM. In the adjusted model, there was no difference in risk of ileus among patients exposed to alogliptin compared with patients exposed to other DPP-4 inhibitors (IRR 1.15, 95 % CI 0.75-1.75) or GLP-1 receptor agonists (IRR 0.42, 95 % CI 0.14-1.20). The risk of ileus was significantly lower among patients exposed to alogliptin compared with patients exposed to voglibose (IRR 0.55, 95 % CI 0.35-0.88).

Conclusions

The independent risk of ileus among new users of alogliptin did not significantly differ compared with new users of other DPP-4 inhibitors or GLP-1 receptor agonists but was significantly lower than new users of voglibose.

Dipeptidyl peptidase-4 inhibitor (vildagliptin) improves glycemic control after meal tolerance test by suppressing glucagon release

Aim

We aimed to evaluate changes in insulin and glucagon secretion, as well as glucose levels, with a meal tolerance test (MTT) before and after 6 months of treatment with vildagliptin in a clinical setting.

Materials and Methods

Participants were 15 patients with uncontrolled type 2 diabetes mellitus (glycated hemoglobin [HbA_1c] over 6.9 % for more than 3 months). MTTs were conducted before and 6 months after addition of vildagliptin (50 mg twice daily [bid]). Blood samples were collected immediately before, and 1 and 2 h after the test meal for measurement of blood glucose concentration, immune-reactive insulin (IRI), and glucagon. HbA_1c was measured at 6 months.

Results

Mean age of participants was 55.5 ± 2.8 years, and ten (66.7 %) were male. Mean HbA_1c significantly improved from 7.6 to 6.8 % at 6 months after addition of vildagliptin. Blood glucose at 1 and 2 h after the test meal was significantly reduced after addition of vildagliptin, while the reduction in glucagon showed borderline significance and IRI showed no difference. In a comparison of blood glucose-related parameters between subgroups based on median glucose change in area under the curve during MTT (ΔAUC_0–2h), glucagon ΔAUC_0–2h was significantly lower in the group with more improved glucose levels (ΔAUC_0–2h ≥65 mg/dL), but that of IRI did not differ.

Conclusion

Suppression of glucagon release by vildagliptin may improve glycemic control without increasing insulin levels in patients with type 2 diabetes.

Does the treatment of type 2 diabetes mellitus with the DPP-4 inhibitor vildagliptin reduce HbA1c to a greater extent in Japanese patients than in Caucasian patients?

BACKGROUND

Previous work suggests that Japanese patients with type 2 diabetes mellitus (T2DM) may respond more favorably to a DPP-4 (dipeptidyl peptidase-4) inhibitor than Caucasians. We aimed to compare the efficacy of the DPP-4 inhibitor vildagliptin (50 mg twice daily [bid]) between Japanese and Caucasian populations.

METHODS

This analysis pooled data from 19 studies of drug-naïve patients with T2DM who were treated for 12 weeks with vildagliptin 50 mg bid as monotherapy. The pool comprised Japanese patients (n=338) who had been treated in Japan and Caucasian patients (n=1,275) who were treated elsewhere. Change from baseline (Δ) in glycated hemoglobin (HbA1c) at 12 weeks (in millimoles per mole) versus baseline HbA1c (both in percentage National Glycohemoglobin Standardization Program units [NGSP%] and millimoles per mole) for each population was reported. Universal HbA1c in millimoles per mole was calculated from either the Japanese Diabetes Society or the NGSP% HbA1c standards.

RESULTS

At baseline, mean values for Japanese and Caucasian patients, respectively, were as follows: age, 59 years and 56 years; % male, 69% and 57%. The average HbA1c was reduced from 7.90% to 6.96% (Japanese Diabetes Society) and from 8.57% to 7.50% (United States National Glycohemoglobin Standardization Program), while HbA1c was reduced from 63 mmol/mol to 53 mmol/mol and from 70 mmol/mol to 58 mmol/mol in Japanese and Caucasians, respectively. ΔHbA1c increased with increasing baseline in both populations. The slopes were the same (0.41, r (2)=0.36; and 0.41, r (2)=0.15), and the intercepts were 15.4 mmol/mol and 17.2 mmol/mol, respectively. In Japanese patients, mean ΔHbA1c was greater by 1.7 mmol/mol (0.2% NGSP HbA1c) at any given baseline HbA1c than in Caucasians (P=0.01).

CONCLUSION

The present pooled analysis suggests that Japanese patients respond better to vildagliptin treatment compared with Caucasians. However, when glycemic control was corrected by using the same glycemic standard, the difference in HbA1c reduction between these populations was not clinically meaningful.

Comparisons of the efficacy of glucose control, lipid profile, and β-cell function between DPP-4 inhibitors and AGI treatment in type 2 diabetes patients: a meta-analysis

The aim of this study is to compare the efficacy of dipeptidyl peptidase-4 (DPP-4) inhibitor treatment with α-glucosidase inhibitor (AGI) treatment in patients with type 2 diabetes through a meta-analysis. Studies were identified by a literature search of Medline, Embase, and others from the time that recording commenced until December 2014. The meta-analysis was performed by computing the weighted mean difference (WMD) and 95 % confidence interval (CI) for a change from baseline to the study endpoint for DPP-4 inhibitors versus AGIs. Nine randomized controlled trial were judged to be appropriate for inclusion in the meta-analysis. One thousand and forty-six patients were treated with a DPP-4 inhibitor, while 929 patients were treated with AGI treatment; the groups had a comparable baseline body mass index of 25.5 ± 1.3 kg/m(2) and mean baseline HbA1c of 7.83 ± 0.53 %. Treatment with DPP-4 inhibitors led to a significantly greater change from baseline in the HbA1c levels (WMD -0.30 %; 95 % CI -0.47 to -0.13 %, p < 0.001) and fasting plasma glucose levels (WMD -0.50 mmol/L; 95 % CI -0.89 to -0.11 mmol/L, p = 0.01) compared with AGI treatment. Compared with AGIs, treatment with DPP-4 inhibitors was associated with a significantly greater increase in the weight change from baseline (WMD 0.89 kg; 95 % CI 0.53-1.25, p < 0.001). Treatment with DPP-4 inhibitors was associated with a significantly greater increase in the fasting insulin level from baseline (WMD 0.63 µU/mL; 95 % CI 0.35-0.90 µU/mL, p < 0.001). DPP-4 inhibitors significantly improved homeostatic model assessment for β-cell function in type 2 diabetes patients compared with AGI treatment (WMD 5.43; 95 % CI 1.01-9.85, p = 0.02). DPP-4 inhibitors were associated with a significantly greater decrease in the cholesterol (CHO) level (WMD -0.19 mmol/L; 95 % CI -0.19 to -0.19 mmol/L, p < 0.001) and a significantly greater decrease in the low-density lipoprotein cholesterol (LDL-C) level (WMD -0.16 mmol/L; 95 % CI -0.26 to -0.05 mmol/L, p = 0.003). Compared with AGIs (813 participants), treatment with DPP-4 inhibitors (1031 participants) was associated with a significantly lower incidence of drug-related adverse event (OR 0.48; 95 % CI 0.36-0.64, p < 0.0001). The efficacy of glucose control and improvement of β-cell function, as well as total CHO and LDL-C decreases, in DPP-4 inhibitor treatment were superior to those with AGI treatment, and there was a lower incidence of drug-related AE.

Cardiovascular and heart failure safety profile of vildagliptin: a meta-analysis of 17 000 patients

AIMS

To report the cardiovascular (CV) safety profile and heart failure (HF) risk of vildagliptin from a large pool of studies, including trials in high-risk patients with type 2 diabetes mellitus (T2DM), such as those with congestive HF and/or moderate/severe renal impairment.

METHODS

We conducted a retrospective meta-analysis of prospectively adjudicated CV events. Patient-level data were pooled from 40 double-blind, randomized controlled phase III and IV vildagliptin studies. The primary endpoint was occurrence of major adverse CV events (MACEs; myocardial infarction, stroke and CV death). Assessments of the individual MACE components and HF events (requiring hospitalization or new onset) were secondary endpoints. The risk ratio (RR) of vildagliptin (50 mg once- and twice-daily combined) versus comparators (placebo and all non-vildagliptin treatments) was calculated using the Mantel-Haenszel (M-H) method.

RESULTS

Of the 17 446 patients, 9599 received vildagliptin (9251.4 subject-years of exposure) and 7847 received comparators (7317.0 subject-years of exposure). The mean age of the patients was 57 years, body mass index 30.5 kg/m(2) (nearly 50% obese), glycated haemoglobin concentration 8.1% and T2DM duration 5.5 years. A MACE occurred in 83 (0.86%) vildagliptin-treated patients and 85 (1.20%) comparator-treated patients, with an M-H RR of 0.82 [95% confidence interval (CI) 0.61-1.11]. Similar RRs were observed for the individual events. Confirmed HF events were reported in 41 (0.43%) vildagliptin-treated patients and 32 (0.45%) comparator-treated patients, with an M-H RR 1.08 (95% CI 0.68-1.70).

CONCLUSIONS

This large meta-analysis indicates that vildagliptin is not associated with an increased risk of adjudicated MACEs relative to comparators. Moreover, this analysis did not find a significant increased risk of HF in vildagliptin-treated patients.

Comparison of vildagliptin as an add-on therapy and sulfonylurea dose-increasing therapy in patients with inadequately controlled type 2 diabetes using metformin and sulfonylurea (VISUAL study): A randomized trial

The aim of present study is to compare the efficacy and safety of adding vildagliptin with sulfonylurea dose-increasing as an active comparator in patients who had inadequately controlled type 2 diabetes mellitus (T2DM) using metformin plus sulfonylurea in real clinical practice. Patients using metformin plus sulfonylurea were assigned to either vildagliptin add-on (50 mg twice a day, n=172) or sulfonylurea dose-increasing by 50% (n=172) treatment groups. The primary endpoint was a change in HbA(1c) after 24 weeks. The secondary endpoints were patients achieving HbA(1c)≤7.0% (53 mmol/mol) and changes in the fasting plasma glucose (FPG), 2-h postprandial glucose (2pp), lipid profiles, and urine albumin-to-creatinine ratio. Body weight and hypoglycemia were also investigated. The mean HbA(1c) at baseline was 8.6% (70 mmol/mol) in both groups. At week 24, the adjusted mean HbA(1c) levels decreased by -1.19% (-13.09 mmol/mol) with vildagliptin add-on and -0.46% (-5.06 mmol/mol) with sulfonylurea (P<0.001). Significantly more vildagliptin add-on patients achieved HbA(1c)≤7.0% (53 mmol/mol) than did sulfonylurea patients (40.1% vs. 7.9%; P<0.001). Greater reductions in FPG and 2pp were observed with vildagliptin add-on than with sulfonylurea (P<0.001). The vildagliptin add-on group exhibited no clinically relevant weight gain and had a lower incidence of hypoglycemia compared with the sulfonylurea group. Vildagliptin add-on therapy might be a suitable option for patients with T2DM that is controlled inadequately by metformin and sulfonylurea, based on its greater glucose control and better safety profile (ClinicalTrial.gov: NCT01099137).

The Place of Dipeptidyl Peptidase-4 Inhibitors in Type 2 Diabetes Therapeutics: A "Me Too" or "the Special One" Antidiabetic Class?

Incretin-based therapies, the most recent therapeutic options for type 2 diabetes mellitus (T2DM) management, can modify various elements of the disease, including hypersecretion of glucagon, abnormal gastric emptying, postprandial hyperglycaemia, and, possibly, pancreatic β cell dysfunction. Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) increase glucagon-like peptide-1 (GLP-1) availability and correct the "incretin defect" seen in T2DM patients. Clinical studies have shown good glycaemic control with minimal risk of hypoglycaemia or any other adverse effects, despite the reports of pancreatitis, whose association remains to be proved. Recent studies have been focusing on the putative ability of DPP-4 inhibitors to preserve pancreas function, in particular due to the inhibition of apoptotic pathways and stimulation of β cell proliferation. In addition, other cytoprotective effects on other organs/tissues that are involved in serious T2DM complications, including the heart, kidney, and retina, have been increasingly reported. This review outlines the therapeutic potential of DPP-4 inhibitors for the treatment of T2DM, focusing on their main features, clinical applications, and risks, and discusses the major challenges for the future, in particular the possibility of becoming the preferred therapy for T2DM due to their ability to modify the natural history of the disease and ameliorate nephropathy, retinopathy, and cardiovascular complications.

Fasting during Ramadan: efficacy, safety, and patient acceptability of vildagliptin in diabetic patients

Diabetes management during Ramadan fasting is challenging to the physician in terms of minimizing the risk of hypoglycemia. As compared to oral hypoglycemic agents (OHAs) and sulfonylureas (SUs), which carry a higher and significant risk of hypoglycemia, newer antidiabetic agents such as dipeptidyl peptidase-4 (DPP-4) inhibitors have demonstrated lower risk of hypoglycemia during Ramadan fasting, with better patient compliance. In addition to diabetes education and pre-Ramadan assessments, the physician should also consider use of DPP-4 inhibitors (such as vildagliptin) during Ramadan fasting to minimize the risk of hypoglycemia in type 2 diabetic subjects. Severe episodes of hypoglycemia have been demonstrated in recent research and clinical trials with OHAs/SUs. Conversely, these research observations have also demonstrated comparative safety and efficacy with lower risk of hypoglycemia associated with vildagliptin. Current research review has collected evidence-based clinical trials and observations for the drug vildagliptin to minimize the risk of hypoglycemia during Ramadan fasting, while at the same time focusing the role of diabetes self-management education (DSME), pre-Ramadan assessments, and patient care.

Therapeutic potential of α-glucosidase inhibitors in type 2 diabetes mellitus: an evidence-based review

INTRODUCTION

Postprandial hyperglycemia (PPHG) contributes to micro- and macro-vascular complications more than fasting hyperglycemia in patients with type 2 diabetes mellitus. Due to the traditional carbohydrate-rich diet, Asians, particularly Indians and Chinese need agents to control the higher risk of uncontrolled PPHG. Targeting PPHG with α-glucosidase inhibitors (AGIs), either alone or in combination with other oral hypoglycemic agents and insulin, provide overall glycemic control with transient mild gastrointestinal disorders. Treatment with AGIs, especially acarbose, has also shown to provide beneficial effects on lipid levels, blood pressure, coagulation factors, carotid intima-media thickness and endothelial dysfunction. New insights of acarbose therapy obtained like increased activity of gut hormones and improved gut microbiota may explain the benefits on weight, whereas increased production of H2 may explains its cardiovascular benefits to some extent.

AREAS COVERED

A systematic search strategy was developed to identify randomized controlled trials in MEDLINE, PubMed, EMBASE and ongoing trials databases.

EXPERT OPINION

AGIs as a class and acarbose in particular, are most useful in combatting PPHG and glucose variability across the spectrum of diabetes therapy, particularly in Asian patients. Together with their effects on incretin hormones and gut-microbiota AGIs can be considered beyond glycemic control as 'cardio-protective agents.'

Effects of miglitol, sitagliptin, and initial combination therapy with both on plasma incretin responses to a mixed meal and visceral fat in over-weight Japanese patients with type 2 diabetes. "the MASTER randomized, controlled trial"

AIM

To assess changes in circulating incretin levels and body fat compositions with initial combination therapy with α-glucosidase inhibitor and dipeptidyl peptidase-4 inhibitor in patients with type 2 diabetes (T2D).

METHODS

In this multicenter open-label 24-week trial, Japanese over-weight (BMI ≥ 25 kg/m(2)) patients with T2D not taking medication or taking metformin and/or sulfonylurea were randomly assigned to receive either 50mg of miglitol three times a day (M, n=14), 50mg of sitagliptin once a day (S, n=14), or a combination of both (M+S, n=13). Changes in plasma incretin levels during a meal tolerance test (MTT) and body fat composition with impedance method were evaluated.

RESULTS

During MTT, postprandial plasma glucose levels decreased more after M+S than after M or S, and postprandial serum insulin levels decreased significantly after M and M+S whereas they increased after S. After M, active gastric inhibitory polypeptide (aGIP) decreased significantly at 30 min despite a significant increase at 120 min. After S, aGIP levels increased significantly throughout the MTT. After M+S, aGIP increased significantly at 0 and 120 min despite of significant decrease at 30 min. M+S further enhanced postprandial active glucagon-like peptide-1 levels during MTT than S did. Total body fat mass decreased significantly after M and M+S. Visceral fat mass decreased significantly only after M+S. Serum adiponectin increased significantly only after M+S.

CONCLUSIONS

In over-weight patients with T2D, M+S may have a beneficial effect on adiposity with relation to these different effects on two incretins.

Randomized controlled clinical trial of a combination therapy of vildagliptin plus an α-glucosidase inhibitor for patients with type II diabetes mellitus

The aim of this study was to assess the efficacy of a combination therapy of vildagliptin plus an α-glucosidase inhibitor for patients with type II diabetes mellitus. Type II diabetic patients exhibiting poor glycemic control following α-glucosidase inhibitor treatment for at least two months were selected and randomly distributed into vildagliptin and placebo groups. The body weight, fasting blood glucose (FBG), postprandial glucose (PPG), glycated hemoglobin (HBA1c) and blood lipid levels and hepatorenal functions of the patients were determined before and 12 weeks after the trial. Following the trial, the FBG, PPG, HbA1c, cholesterol (CHOL) and triglyceride (TG) levels in the vildagliptin group were significantly decreased compared with the pretreatment levels (P<0.05), whereas only the PPG level in the placebo group decreased (P<0.05). The FBG, PPG and HbA1c levels in the vildagliptin group were markedly lower than those in the placebo group 12 weeks after the trial. A comparison of the body weights and hepatorenal functions before and after the trial or between groups did not show statistically significant differences. The combination therapy of vildagliptin plus an α-glucosidase inhibitor effectively reduced the FBG, PPG and HbA1c levels in patients without inducing weight gain or hepatorenal dysfunction. However, the therapy may have caused a reduction in the blood lipid levels.

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.

Efficacy of voglibose in type 2 diabetes

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is currently at epidemic proportions and the forecast is for a continued sharp increase in global prevalence. An even larger proportion of the population has prediabetes (impaired glucose tolerance [IGT]) underscoring the urgent need for preventive strategies. Even in the presence of adequate glycosylated hemoglobin (HbA1c) levels, postprandial hyperglycemia can occur and is known to have a stronger association with cardiovascular morbidity than fasting glucose. The α-glucosidase inhibitor voglibose is widely used in Japan to improve postprandial hyperglycemia.

AREAS COVERED

This review examines the literature for the pharmacology, pharmacokinetics, clinical efficacy and safety of voglibose in patients with T2DM. Particular focus is on its efficacy in preventing T2DM in individuals with IGT and its efficacy as add-on therapy or in combination with other oral antidiabetic agents in patients with T2DM.

EXPERT OPINION

As the relationship between glucose levels and cardiovascular risk extends below the diabetic threshold, postprandial hyperglycemia is recognized as a key therapeutic target in the treatment of T2DM. Strategies to prevent the progression of IGT to overt T2DM have enormous potential to reduce the individual and societal burden of disease. Voglibose is the first oral antidiabetic agent to gain approval in Japan for this indication.

Efficacy of initial Basal-supported oral therapy with sitagliptin in untreated type 2 diabetes

INTRODUCTION

The present study assessed the efficacy of initial basal-supported oral therapy (BOT) with sitagliptin for achievement of glycemic control and subsequent switching from BOT to sitagliptin-based oral therapy.

METHODS

Nineteen recently diagnosed type 2 diabetic patients who had received no antidiabetic medication in the previous 2 years were sequentially examined for the 24-week study. Patients were initially treated with a combination of insulin glargine and sitagliptin. Sitagliptin was initiated and maintained at a dose of 50 mg/day, and insulin glargine was started at a dose of 4 U at bedtime and adjusted if needed.

RESULTS

During the 24-week treatment period, 12 patients (63%) achieved HbA1c levels <7% (mean BOT duration 13.7 ± 5.6 weeks) and switched from BOT to sitagliptin monotherapy or in combination with metformin (achievers). The remaining seven patients (37%) failed to achieve HbA1c levels <7% (non-achievers) and continued on BOT. Both FPG and HbA1c in achievers significantly dropped at 4, 8, 12 and 24 weeks from baseline, while those in non-achievers significantly decreased at 12 and 24 weeks from baseline, but failed to reach target glycemic control. There were statistically significant differences in FPG at 4, 8, 12 and 24 weeks and in HbA1c at 8, 12 and 24 weeks between achievers and non-achievers. Body weight and BMI in achievers were significantly reduced at 12 and 24 weeks, but those in non-achievers did not change significantly. Dosage of concomitant insulin during BOT was significantly lower in achievers compared to non-achievers. Non-achievers had a similar CPI, a measure of insulin secretion capacity, to achievers, but significantly showed an insulin resistance index (value of 20/[fasting CPR × FPG]), in comparison to achievers.

CONCLUSION

Initiating BOT with sitagliptin followed by sitagliptin-based oral therapy is a useful option in untreated and poorly controlled patients with type 2 diabetes.

Linagliptin provides effective, well-tolerated add-on therapy to pre-existing oral antidiabetic therapy over 1 year in Japanese patients with type 2 diabetes

AIMS

To evaluate the long-term safety and efficacy of linagliptin as add-on therapy to one approved oral antidiabetic drug (OAD) in Japanese patients with type 2 diabetes mellitus and insufficient glycaemic control.

METHODS

This 52-week, multicentre, open-label, parallel-group study evaluated once-daily linagliptin 5 mg as add-on therapy to one OAD [biguanide, glinide, glitazone, sulphonylurea (SU) or α-glucosidase inhibitors (A-GI)] in 618 patients. After a 2-week run-in, patients on SU or A-GI were randomized to either linagliptin (once daily, 5 mg) or metformin (twice or thrice daily, up to 2250 mg/day) as add-on therapy. Patients receiving the other OADs received linagliptin add-on therapy (non-randomized).

RESULTS

Adverse events were mostly mild or moderate, and rates were similar across all groups. Hypoglycaemic events were rare, except in the SU group. Overall, 26 (5.8%) hypoglycaemic events were reported in patients receiving linagliptin (non-randomized). Hypoglycaemic events were similar for linagliptin and metformin added to A-GI (1/61 vs. 2/61, respectively) or SU (17/124 vs. 10/63, respectively). Significant reductions in glycated haemoglobin (HbA1c) levels (between -0.7 and -0.9%) occurred throughout the study period for the background therapy groups that received linagliptin (baseline HbA1c 7.9-8.1%). The decline in HbA1c levels was indistinguishable between linagliptin and metformin groups when administered as add-on therapy to A-GI or SU.

CONCLUSIONS

Once-daily linagliptin showed safety and tolerability over 1 year and provided effective add-on therapy leading to significant HbA1c reductions, similar to metformin, over 52 weeks in Japanese patients.

A review of newer treatment approaches for type-2 diabetes: Focusing safety and efficacy of incretin based therapy

Diabetes resulting from both genetic and lifestyle factors causes high insulin deficiency or its resistance. As hyperglycemia and decreased insulin secretion and/or its sensitivity appear to be the primary defects associated with diabetes, available treatments focus on reducing those defects. A novel approach of treatment is to target the incretin mimetic hormones, which are secreted by intestinal cells in response to food intake, provoking glucose-dependent insulin secretion from the pancreas. Efficacy and safety studies of dipetidyl peptidase inhibitors (DPP-IV), sitagliptin, vildagliptin and linagliptin provide similar improvements in HbA1c levels when compared with metformin, sulfonylureas or glitazones without contributing to weight gain and hypoglycemia. Caution is required when choosing the gliptin in people with renal or hepatic impairment and with a risk of pancreatitis. The glucagon like peptide (GLP-1) analogues Exenatide and Liraglutide also have positive impact on glycemic control especially when used as a combination therapy. Another upcoming approach is using sodium-glucose co transporter two inhibitors in kidney, by exploring pathophysiology of renal glucose re absorption in the proximal tubule.

Profile of vildagliptin in type 2 diabetes: efficacy, safety, and patient acceptability

Vildagliptin is a selective and potent dipeptidyl peptidase-4 inhibitor that improves glycemic control by inhibiting the degradation of both endogenous glucagon-like peptide-1 and glucose-dependent insulinotropic peptide. This article is a comprehensive review of the safety and efficacy of vildagliptin in patients with type 2 diabetes. Clinical evidence has proven that it effectively decreases hemoglobin A_1c with a low risk of hypoglycemia and is weight neutral. The addition of vildagliptin to metformin improves glucose control and significantly reduces gastrointestinal adverse events, particularly in patients inadequately controlled with metformin monotherapy. Its long-term advantages include preservation of β-cell function, reduction in total cholesterol, decrease in fasting lipolysis in adipose tissue, and triglyceride storage in non-fat tissues. Vildagliptin is well tolerated with a low incidence of AEs, and it does not increase the risk of cardiovascular/cerebrovascular (CCV) events. It can be taken before or after meals, and has little drug interaction, thus it will be well accepted.

Efficacy and safety of linagliptin in subjects with type 2 diabetes mellitus and poor glycemic control: pooled analysis of data from three placebo-controlled phase III trials

AIMS

To evaluate the efficacy/safety of dipeptidyl peptidase-4 inhibitor, linagliptin, in subjects with insufficiently controlled type 2 diabetes mellitus (T2DM), and factors influencing treatment response.

METHODS

Pooled analysis of data from 2258 subjects in three 24-week phase III, randomized, placebo-controlled, parallel-group studies, who received oral linagliptin (5 mg/day) or placebo as monotherapy, added-on to metformin, or added-on to metformin plus sulfonylurea was performed.

RESULTS

Among 388 subjects with HbA1c ≥9.0%, adjusted mean baseline HbA1c (9.4% both groups) declined to 8.3% in linagliptin group and 9.1% in placebo group at 24 weeks (P<.0001) and adjusted mean change from baseline was 1.2% (vs. 0.4%, placebo). Linagliptin significantly lowered fasting plasma glucose levels vs. placebo (1.6 mmol/l vs. 0.4 mmol/l); treatment difference, 1.1 mmol/l (95% CI, -1.7 to -0.5). Treatment and washout of previous oral antidiabetes drugs were the only factors to independently affect HbA1c change at week 24. Adverse event rates were similar for linagliptin (61.9%) and placebo (62.7%). Hypoglycemia was rare with linagliptin monotherapy/add-on to metformin (≤1%) and increased when linagliptin was added to metformin plus sulfonylurea (linagliptin, 17.9% vs. placebo, 8.3%).

CONCLUSIONS

Linagliptin was an effective, well-tolerated treatment in subjects with T2DM and insufficient glycemic control, both as monotherapy or added-on to metformin/metformin plus sulfonylurea.

Predictive clinical parameters and glycemic efficacy of vildagliptin treatment in korean subjects with type 2 diabetes

BACKGROUND

The aims of this study are to investigate the glycemic efficacy and predictive parameters of vildagliptin therapy in Korean subjects with type 2 diabetes.

METHODS

In this retrospective study, we retrieved data for subjects who were on twice-daily 50 mg vildagliptin for at least 6 months, and classified the subjects into five treatment groups. In three of the groups, we added vildagliptin to their existing medication regimen; in the other two groups, we replaced one of their existing medications with vildagliptin. We then analyzed the changes in glucose parameters and clinical characteristics.

RESULTS

Ultimately, 327 subjects were analyzed in this study. Vildagliptin significantly improved hemoglobin A1c (HbA1c) levels over 6 months. The changes in HbA1c levels (ΔHbA1c) at month 6 were -2.24% (P=0.000), -0.77% (P=0.000), -0.80% (P=0.001), -0.61% (P=0.000), and -0.34% (P=0.025) for groups 1, 2, 3, 4, and 5, respectively, with significance. We also found significant decrements in fasting plasma glucose levels in groups 1, 2, 3, and 4 (P<0.05). Of the variables, initial HbA1c levels (P=0.032) and history of sulfonylurea use (P=0.026) were independently associated with responsiveness to vildagliptin treatment.

CONCLUSION

Vildagliptin was effective when it was used in subjects with poor glycemic control. It controlled fasting plasma glucose levels as well as sulfonylurea treatment in Korean type 2 diabetic subjects.

Efficacy of vildagliptin on glucose fluctuation in Japanese type 2 diabetic patients with ongoing sulfonylurea based oral glycemic agent therapy

AIM

To investigate whether vildagliptin, one of the dipeptidylpeptide-4 (DDP-4) inhibitors, improves not only glycemic control but also glycemic fluctuation when added to ongoing sulfonylurea (SU) based oral hypoglycemic agents (OHA) therapy in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 19 patients with T2DM were recruited from outpatients. Vildagliptin was initiated with a dose of 100mg per day in the patients who had inadequate glycemic control and glycemic fluctuation with ongoing SU based OHA therapy. Glycemic excursion was defined by seven-point self-monitoring blood glucose (SMBG) on three days at baseline and 12 weeks after vildagliptin-combined therapy, as well as HbA1c levels. M-value and J-index were calculated to evaluate glycemic excursion.

RESULTS

Addition of vildagliptin to ongoing SU based OHA therapy significantly decreased HbA1c values from 8.2 ± 3.8% at baseline to 7.3 ± 0.8% at 12-week. The average of blood glucose profiles was significant improved. As a result, M-value was significantly corrected from 20.9 ± 14.4 to 12.2 ± 13.5 and J-index from 55.1 ± 25.5 to 39.1 ± 19.8.

CONCLUSIONS

Vildagliptin when added to ongoing SU based OHA therapy for 12 weeks significantly improved glycemic fluctuation as well as glycemic control in Japanese patients with T2DM.

Efficacy and safety of dipeptidyl peptidase-4 inhibitors in type 2 diabetes: meta-analysis

BACKGROUND

An up-to-date assessment of dipeptidyl peptidase-4 (DPP-4) inhibitors is needed to include newly available data.

OBJECTIVE

To assess the efficacy and safety of DPP-4 inhibitors, including sitagliptin, saxagliptin, vildagliptin, and linagliptin, in type 2 diabetes.

METHODS

We conducted a search of MEDLINE for randomized controlled trials (RCTs) of DPP-4 inhibitors in type 2 diabetes through November 2011, using the key terms sitagliptin, saxagliptin, vildagliptin, and linagliptin. We also searched for completed, but unpublished, trials at relevant web sites. RCTs were selected for meta-analysis if they (1) compared DPP-4 inhibitors with placebo or an antihyperglycemic agent; (2) had study duration of 12 or more weeks; (3) had 1 or more baseline and posttreatment efficacy and/or safety outcome; and (4) were published in English.

RESULTS

In 62 evaluated articles, DPP-4 inhibitors lowered hemoglobin A(1c) (A1C) significantly more than placebo (weighted mean difference [WMD] -0.76%; 95% CI -0.83 to -0.68); however, heterogeneity was substantial (I(2) = 82%). Exclusion of Japanese trials (n = 7) resulted in a reduction of heterogeneity (I(2) = 59%). In the non-Japanese RCTs (n = 55), DPP-4 inhibitors were associated with a reduction in A1C (WMD -0.65%; 95% CI -0.71 to -0.60) but higher risk of hypoglycemia (odds ratio [OR] 1.30; 95% CI 1.00 to 1.68) compared to placebo. The 7 Japanese-specific RCTs showed a greater reduction in A1C (WMD -1.67%; 95% CI -1.89 to -1.44) and a nonsignificant increase in risk of hypoglycemia (OR 1.41; 95% CI 0.51 to 3.88) with DPP-4 inhibitors versus placebo. When comparing DPP-4 inhibitors to active comparators, the I(2) was still high after deleting Japanese studies. In these 17 active comparator trials, there was no significant difference in A1C reduction (WMD 0.04%; 95% CI -0.09 to 0.16) or risk of hypoglycemia (OR 0.60; 95% CI 0.22 to 1.61) for DPP-4 inhibitors compared to other antihyperglycemics. There were similar odds of any or serious adverse events with DPP-4 inhibitors compared to placebo, but a decreased risk compared to other antihyperglycemics.

CONCLUSIONS

DPP-4 inhibitors were associated with a reduction in A1C with comparable safety profiles compared to placebo, but no significant difference in A1C compared to other hyperglycemics. Differences in efficacy and safety were observed between Japanese and non-Japanese patients.

Quantitative Evaluation of Compliance with Recommendation for Sulfonylurea Dose Co-Administered with DPP-4 Inhibitors in Japan

After the launch of dipeptidyl peptidase-4 (DPP-4), a new oral hypoglycemic drug (OHD), in December 2009, severe hypoglycemia cases were reported in Japan. Although the definite cause was unknown, co-administration with sulfonylureas (SU) was suspected as one of the potential risk factors. The Japan Association for Diabetes Education and Care (JADEC) released a recommendation in April 2010 to lower the dose of three major SUs (glimepiride, glibenclamide, and gliclazide) when adding a DPP-4 inhibitor. To evaluate the effectiveness of this risk minimization action along with labeling changes, dispensing records for 114,263 patients prescribed OHDs between December 2008 and December 2010 were identified in the Nihon-Chouzai pharmacy claims database. The adherence to the recommended dosing of SU co-prescribed with DPP-4 inhibitors increased from 46.3% before to 63.8% after the JADEC recommendation (p < 0.01 by time-series analysis), while no change was found in those for SU monotherapy and SU with other OHD co-prescriptions. The adherence was significantly worse for those receiving a glibenclamide prescription. The JADEC recommendation, along with labeling changes, appeared to have a favorable effect on the risk minimization action in Japan. In these instances, a pharmacy claims database can be a useful tool to evaluate risk minimization actions.

Matching-adjusted indirect comparisons: a new tool for timely comparative effectiveness research

OBJECTIVE

In the absence of head-to-head randomized trials, indirect comparisons of treatments across separate trials can be performed. However, these analyses may be biased by cross-trial differences in patient populations, sensitivity to modeling assumptions, and differences in the definitions of outcome measures. The objective of this study was to demonstrate how incorporating individual patient data (IPD) from trials of one treatment into indirect comparisons can address several limitations that arise in analyses based only on aggregate data.

METHODS

Matching-adjusted indirect comparisons (MAICs) use IPD from trials of one treatment to match baseline summary statistics reported from trials of another treatment. After matching, by using an approach similar to propensity score weighting, treatment outcomes are compared across balanced trial populations. This method is illustrated by reviewing published MAICs in different therapeutic areas. A novel analysis in attention deficit/hyperactivity disorder further demonstrates the applicability of the method. The strengths and limitations of MAICs are discussed in comparison to those of indirect comparisons that use only published aggregate data.

RESULTS

Example applications were selected to illustrate how indirect comparisons based only on aggregate data can be limited by cross-trial differences in patient populations, differences in the definitions of outcome measures, and sensitivity to modeling assumptions. The use of IPD and MAIC is shown to address these limitations in the selected examples by reducing or removing the observed cross-trial differences. An important assumption of MAIC, as in any comparison of nonrandomized treatment groups, is that there are no unobserved cross-trial differences that could confound the comparison of outcomes.

CONCLUSIONS

Indirect treatment comparisons can be limited by cross-trial differences. By combining IPD with published aggregate data, MAIC can reduce observed cross-trial differences and provide decision makers with timely comparative evidence.

Efficacy and tolerability of vildagliptin as add-on therapy to metformin in Chinese patients with type 2 diabetes mellitus

AIM

To investigate the efficacy and tolerability of vildagliptin as add-on therapy to metformin in Chinese patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin.

METHODS

This was a 24-week, randomized, double-blind, placebo-controlled study. Patients with T2DM (N = 438) with haemoglobin A1c (HbA1c) of 7.0-10.0% and fasting plasma glucose (FPG) <15 mmol/l (<270 mg/dl) were randomized (1 : 1 : 1) to vildagliptin 50 mg bid, vildagliptin 50 mg qd or placebo in addition to metformin.

RESULTS

The treatment groups were well balanced at baseline [mean HbA1c, 8.0%, FPG, 8.8 mmol/l (158 mg/dl); body mass index, 25.5 kg/m(2) ]. The adjusted mean change (AMΔ) in HbA1c at endpoint was -1.05 ± 0.08%, -0.92 ± 0.08% and -0.54 ± 0.08% in patients receiving vildagliptin 50 mg bid, 50 mg qd and placebo, respectively. The between-treatment difference (vildagliptin 50 mg bid-placebo) was -0.51 ± 0.11%, p < 0.001. A greater proportion of vildagliptin-treated patients met at least one responder criterion (82.1 and 70.7%) compared to placebo-treated patients (60.4%). The AMΔ at endpoint for FPG with vildagliptin 50 mg bid, -0.95 mmol/l (-17.1 mg/dl); 50 mg qd, -0.84 mmol/l (-15.1 mg/dl) was significantly different compared with the placebo -0.26 mmol/l (-4.68 mg/dl) (p ≤ 0.001). Adverse events (AEs) were reported as 34.2, 36.5 and 37.5% for patients receiving vildagliptin 50 mg bid, 50 mg qd or placebo, respectively. Two patients in the vildagliptin 50 mg qd and one in the placebo group reported serious AEs, which were not considered to be related to the study drug; one incidence of hypoglycaemic event was reported in the vildagliptin 50 mg bid group.

CONCLUSION

Vildagliptin as add-on therapy to metformin improved glycaemic control and was well tolerated in Chinese patients who were inadequately controlled by metformin only.

Drug-induced hypoglycaemia in type 2 diabetes

INTRODUCTION

Hypoglycaemia is a side effect caused by some therapies for type 2 diabetes, which can cause physical, social and psychological harm. Hypoglycaemia also prevents attainment of treatment goals and satisfactory glycaemic control.

AREAS COVERED

The risk of hypoglycaemia associated with commonly prescribed therapies, including metformin, sulphonylureas, dipeptidyl peptidase-4 enzyme (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) agonists and thiazolidinediones, is reviewed in this paper (insulin-induced hypoglycaemia is not included). Other medications that are frequently co-prescribed in type 2 diabetes are also discussed, including anti-hypertensive drugs, antibiotics and fibrates, along with various important patient-related risk factors.

EXPERT OPINION

Hypoglycaemia is a common and potentially dangerous side effect of some medications used for type 2 diabetes. The risk of hypoglycaemia should always be considered when selecting and implementing a therapy, with a focus on the individual. Future research into new therapies should measure the frequency of hypoglycaemia prospectively and accurately. Hypoglycaemia has been shown to be a potentially life-threatening metabolic stress; therefore therapies that effectively manage diabetes without the risk of hypoglycaemia are likely to be favoured in the future.

Clinical pharmacokinetics and pharmacodynamics of vildagliptin

Vildagliptin is an orally active, potent and selective dipeptidyl peptidase-4 (DPP-4) inhibitor, shown to be effective and well tolerated in patients with type 2 diabetes mellitus (T2DM) as either monotherapy or in combination with other anti-diabetic agents. Vildagliptin possesses several desirable pharmacokinetic properties that contribute to its lower variability and low potential for drug interaction. Following oral administration, vildagliptin is rapidly and well absorbed with an absolute bioavailability of 85%. An approximately dose-proportional increase in exposure to vildagliptin over the dose range of 25-200 mg has been reported. Food does not have a clinically relevant impact on the pharmacokinetics of vildagliptin, and it can be taken without regard to food. Vildagliptin is minimally bound to plasma proteins (9.3%) and, on the basis of a volume of distribution of 71 L, it is considered to distribute extensively into extravascular spaces. Renal clearance of vildagliptin (13 L/h) accounts for 33% of the total body clearance after intravenous administration (41 L/h). The primary elimination pathway is hydrolysis by multiple tissues/organs. The DPP-4 enzyme contributes to the formation of the major hydrolysis metabolite, LAY151; therefore, vildagliptin is also a substrate of DPP-4. Vildagliptin has a low potential for drug interactions, as cytochrome P450 (CYP) enzymes are minimally (<1.6%) involved in the overall metabolism. Clinical pharmacokinetic studies have reported the lack of drug interaction with several drugs (metformin, pioglitazone, glyburide, simvastatin, amlodipine, valsartan, ramipril, digoxin and warfarin) that are likely to be frequently co-administered to patients with T2DM. In particular, vildagliptin does not affect the pharmacokinetics of pioglitazone, glyburide, warfarin and simvastatin; therefore, it is not expected to affect the pharmacokinetics of a drug that is a substrate for CYP2C8, CYP2C9 or CYP3A4. In the elderly, vildagliptin exposure increases by approximately 30%, which is considered to be mostly attributable to compromised renal function in the elderly population and is not considered to be clinically relevant. Vildagliptin has been demonstrated to be efficacious, safe and well tolerated in elderly patients with T2DM without dose adjustment. In subjects with varying degrees of renal impairment, vildagliptin exposure increases by approximately 2-fold; however, the increase in the exposure does not correlate with the severity of renal impairment. The lack of a clear correlation between the increased exposure and the severity of renal impairment is considered to be attributable to the fact that the kidneys contribute to both the excretion and the hydrolysis metabolism of vildagliptin. Hepatic impairment, gender, body mass index (BMI) and ethnicity do not have an influence on the pharmacokinetics of vildagliptin. These findings suggest that vildagliptin can be used in a diverse patient population without dose adjustment. Oral administration of vildagliptin to patients with T2DM completely inhibits DPP-4 activity at a variety of doses. The onset of DPP-4 inhibition is rapid, and the duration of DPP-4 inhibition is dose dependent. Vildagliptin is a potent inhibitor of the DPP-4 enzyme, with a concentration required to achieve 50% DPP-4 inhibition (IC(50)) of 4.5 nmol/L in patients with T2DM. Similar potency of DPP-4 inhibition by vildagliptin has been reported in different ethnic groups, indicating that ethnicity does not affect the pharmacodynamics of vildagliptin. Vildagliptin significantly increases the active glucagon-like peptide 1 (GLP-1) levels by approximately 2- to 3-fold and glucose-dependent insulinotropic polypeptide (GIP) levels by approximately 5-fold, and significantly suppresses the postprandial glucagon levels in response to a meal or following an oral glucose tolerance test (OGTT) in patients with T2DM. Vildagliptin significantly reduces both fasting and postprandial glucose levels over the dose range of 50-100 mg daily (administered either once daily or twice daily), and there are no substantial additional benefits of doses greater than 50 mg twice daily. The primary clinical dosing regimen is 50 mg twice daily as monotherapy or in combination with metformin. Vildagliptin increases the insulin levels following an OGTT and an intravenous glucose tolerance test (IVGTT), and the stimulation of insulin secretion is glucose dependent. Vildagliptin has been shown to improve beta-cell function on the basis of pharmacodynamic modelling taking the reduced glucose levels into account. The improvement of beta-cell function by vildagliptin has been confirmed after chronic treatment with vildagliptin for up to 2 years. Reduction of the endogenous glucose production appears to contribute to the glucose-lowering effects. Unlike the GLP-1 receptor agonists, vildagliptin does not affect gastric emptying, and this is consistent with the favourable gastrointestinal safety profile. Vildagliptin improves the sensitivity of the alpha cell to glucose in patients with T2DM by enhancing the alpha-cell responsiveness to both suppressive effects of hyperglycaemia and stimulatory effects of hypoglycaemia. Consistently, a lower incidence of hypoglycaemic events with vildagliptin is reported when it is used as either monotherapy or in combination with other anti-diabetic agents, such as metformin or insulin, as compared with a sulphonylurea. Numerous long-term clinical trials of up to 2 years have demonstrated that vildagliptin 50 mg once daily or twice daily is effective, safe and well tolerated in patients with T2DM as either monotherapy or in combination with a variety of other anti-diabetic agents.