Sitagliptin added to treatment with ongoing pioglitazone for up to 52 weeks improves glycemic control in Japanese patients with type 2 diabetes

Prescription patterns and therapeutic effects of second-line drugs in Japanese patients with type 2 diabetes mellitus: Analysis of claims data for metformin and dipeptidyl peptidase-4 inhibitors as the first-line hypoglycemic agents

BACKGROUND

Dipeptidyl peptidase-4 inhibitors (DPP4is) and metformin are the most frequently prescribed first-line drugs for Japanese patients with type 2 diabetes (T2D). We investigated the risk of cardiovascular events by second-line treatment type in these patients.

RESEARCH DESIGN AND METHODS

Patients with T2D, prescribed either metformin or DPP4i as a first-line drug, were identified in claims data from Japanese acute care hospitals. The primary and secondary outcomes were cumulative risks of MI or stroke and of death, respectively, from second-line treatment initiation.

RESULTS

Patients prescribed first-line metformin or DPP4i was 16,736 and 74,464, respectively. In patients receiving first-line DPP4i, the death incidence was lower in those receiving second-line metformin than in those receiving second-line sulfonylurea (p < 0.001), whereas the primary outcome was not significantly different. No significant differences were observed for either outcome when DPP4is and metformin were used as first- and second-line drugs or vice versa.

CONCLUSIONS

Metformin was suggested to have larger effect to reduce death than sulfonylurea in patients receiving first-line DPP4i. The order of first- and second-line for the DPP4i and metformin combination did not affect the outcomes. Given the nature of the study design, certain limitations, including potential under-adjustment for confounders, should be considered.

A randomized, placebo-controlled trial to assess the efficacy and safety of sitagliptin in Japanese patients with type 2 diabetes and inadequate glycaemic control on ipragliflozin

AIMS

To investigate the efficacy, safety and tolerability of sitagliptin 50 mg once daily added to ipragliflozin 50 mg once daily monotherapy in Japanese patients with type 2 diabetes (T2D).

MATERIALS AND METHODS

Japanese patients with T2D and glycated haemoglobin (HbA1c) 7.0% to 10.0% while treated with ipragliflozin 50 mg once daily were randomized 1:1 to additional treatment with sitagliptin 50 mg once daily (N = 70) or matching placebo (N = 71) for 24 weeks. The primary efficacy endpoint was change in HbA1c at Week 24. Secondary efficacy endpoints were changes in 2-hour post-meal glucose (PMG), total PMG 0- to 2-hour area under the curve (AUC_0-2h ), and fasting plasma glucose (FPG).

RESULTS

Baseline characteristics were similar in the two groups (mean age 55.5 years, mean baseline HbA1c 8.0%). After 24 weeks, the addition of sitagliptin provided significantly greater reduction in HbA1c compared to placebo (least squares [LS] mean difference -0.83% [95% confidence interval -1.05, -0.62]; P <0.001). Significant reductions were also observed in all secondary endpoints: LS mean differences from placebo in changes in 2-hour PMG, total PMG AUC_0-2h , and FPG were -42.5 mg/dL, -67.0 mg·h/dL and -11.2 mg/dL, respectively (all P <0.001). The incidence of adverse events (AEs) overall and incidence of predefined AEs of clinical interest (symptomatic hypoglycaemia, urinary tract infection, genital infection, hypovolaemia and polyuria/pollakiuria) were similar in the two groups.

CONCLUSIONS

In Japanese patients with T2D, sitagliptin 50 mg once daily added to ipragliflozin 50 mg once daily monotherapy provided significant improvement in glycaemic control and was generally well tolerated. ClinicalTrials.gov: NCT02577016.

Long-Term Safety and Efficacy of Sitagliptin for Type 2 Diabetes Mellitus in Japan: Results of a Multicentre, Open-Label, Observational Post-Marketing Surveillance Study

Introduction

A post-marketing surveillance (PMS) study was conducted to confirm the long-term risk–benefit profile of sitagliptin administered to Japanese patients with type 2 diabetes mellitus (T2DM) under real-world conditions.

Methods

This prospective, multicentre, open-label PMS collected data from 3326 patients receiving sitagliptin according to the approved indication during the case registration period (July 2010–June 2012; observation period, 3 years). Safety was assessed via collection of data on adverse drug reactions (ADRs), estimated glomerular filtration rate (eGFR) and cardiovascular events whereas efficacy was assessed via changes in glycated hemoglobin (HbA1c).

Results

In 3265 patients evaluated for safety, 270 ADRs occurred in 207 (6.3%) patients overall. Metabolism and nutrition disorders were the most common class of ADRs, occurring in 58 patients overall (53 non-serious, 5 serious) with hypoglycaemia (17 patients, 0.52%) the most common ADR. In patients with eGFR > 90 mL/min/1.73 m² at baseline (mean ± SD, 106.42 ± 18.11 mL/min/1.73 m², n = 584), eGFR declined by 11.83 ± 17.53 mL/min/1.73 m² (P < 0.0001; n = 360) over the observation period whereas eGFR appeared to be relatively maintained in patients with lower baseline eGFR levels. Cardiovascular events were infrequent [occurring in 4 of 84 (4.76%) patients at high cardiovascular risk] with no distinct features in this Japanese population and the cumulative incidence [8.42% (3.12–21.70) at 36 months; n = 32] was similar to that noted in previous studies involving sitagliptin. In patients evaluated for efficacy, the overall change in HbA1c from baseline to final evaluation was mean ± SD − 0.68 ± 1.34% (P < 0.0001, n = 2070). Reductions in HbA1c tended to be greater in younger patients and patients with higher body mass index (BMI) and HbA1c values at the start of administration.

Conclusion

Long-term sitagliptin administration in the routine clinical practice setting is associated with good efficacy, including as monotherapy, with no additional safety concerns.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01293-2) contains supplementary material, which is available to authorized users.

Factors associated with the glucose-lowering efficacy of sitagliptin in Japanese patients with type 2 diabetes mellitus: Pooled analysis of Japanese clinical trials

AIMS/INTRODUCTION

To explore the factors associated with the glucose-lowering efficacy of sitagliptin treatment in Japanese patients with type 2 diabetes mellitus.

MATERIALS AND METHODS

This was a post-hoc analysis of pooled data from seven sitagliptin phase II and III clinical studies carried out in Japan. All studies were double-blind, randomized, placebo-controlled, parallel-group and of 12-week duration. The analysis population consisted of 1,075 type 2 diabetes mellitus patients. In two of the trials, sitagliptin 50 mg and/or 100 mg daily were used as monotherapy; in five others, sitagliptin 50 mg daily was used as add-on treatment to ongoing pioglitazone, glimepiride, metformin, voglibose or glinides. Efficacy (reduction in hemoglobin A1c [HbA1c]) was evaluated in 12 sets of subgroups defined by demographic, glycemic, pancreatic β-cell function and insulin resistance parameters. An analysis of covariance model was used to evaluate the interaction between each parameter and efficacy.

RESULTS

Sitagliptin consistently provided a clinically meaningful reduction in HbA1c relative to placebo across all subgroups. Within subgroups, a greater absolute HbA1c reduction was associated with higher baseline HbA1c, fasting plasma glucose and 2-h post-meal glucose. Lower β-cell function, represented by homeostatic model assessment of β-cell function and insulinogenic index, was also associated with greater HbA1c reduction. In contrast, age, sex, body mass index, duration of type 2 diabetes mellitus and insulin resistance-related parameters did not interact with HbA1c changes.

CONCLUSIONS

Sitagliptin treatment was associated with clinically meaningful improvement in glycemic control in all subgroups of Japanese patients with type 2 diabetes mellitus that were evaluated. Higher baseline glycemic status and lower baseline β-cell function were identified as factors associated with greater HbA1c reduction after sitagliptin treatment.

Renal Function During an Open-Label Prospective Observational Trial of Sitagliptin in Patients With Diabetes: A Sub-Analysis of the JAMP Study

BACKGROUND

The aim of the study was to determine the effects of sitagliptin on renal function in a diabetic population including patients with normal renal function.

METHODS

We analyzed the association between 12-month, 50 mg/day sitagliptin and renal function in outpatients with type 2 diabetes mellitus and poor blood glucose control in a subset of patients in the larger Januvia Multicenter Prospective Trial in Type 2 Diabetes observational study. Stratified analyses of changes in estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) were performed. Factors associated with changes in eGFR at 3 months were examined by multivariate regression analysis.

RESULTS

Of the 779 patients enrolled, 585 were followed up for 12 months. eGFR decreased significantly from baseline at 3 and 12 months in patients with a baseline eGFR of ≥ 90 mL/min/1.73 m2 and in those with a baseline eGFR of ≥ 60 to < 90 mL/min/1.73 m2. Conversely, eGFR tended to increase at 3 and 12 months in patients with a baseline eGFR of ≥ 45 to < 60 mL/min/1.73 m2 and in those with a baseline eGFR of ≥ 30 to < 45 mL/min/1.73 m2. UACR decreased significantly (-21.6 (-46.8, 7.8)) at 3 months in patients with a baseline UACR of ≥ 30 mg/g Cre. Multivariate regression analysis of factors associated with changes in eGFR at 3 months revealed that higher baseline eGFR and greater decline in UACR were associated with more conspicuous decreases in eGFR.

CONCLUSIONS

In this group of diabetic patients receiving sitagliptin, eGFR declined in patients with high baseline eGFR, but not in those with a low baseline eGFR.

Network meta-analysis of liraglutide versus dipeptidyl peptidase-4 inhibitors for the treatment of type 2 diabetes in Japanese patients

AIMS

To determine the comparative efficacy and safety of liraglutide and dipeptidyl peptidase-4 (DPP-4) inhibitors as antidiabetics for Japanese patients with uncontrolled type 2 diabetes (T2DM).

METHODS AND MATERIALS

We searched for randomized controlled trials (RCTs) evaluating outcomes among Japanese adults with uncontrolled T2DM and including liraglutide or DPP-4 inhibitors up to August 2016. We extracted data on trial and patient characteristics, and the following outcomes: HbA1c, weight, patients meeting HbA1c <7%, patients experiencing hypoglycemic events, microalbuminuria, estimated glomerular filtration rate (eGFR) and creatinine. We synthesized data using network meta-analyses (NMA) using a Bayesian framework. Continuous outcomes were modeled using normal likelihoods and an identity link, while dichotomous outcomes were modeled using a binomial likelihood and a logit link.

RESULTS

The systematic literature review yielded 39 publications pertaining to 38 trials. A total of 27 trials (5032 patients) reported change in HbA1c at 12 weeks and at 24 weeks 9 trials (2091 patients). All treatments showed statistically significant reductions in HbA1c relative to placebo at 12 and 24 weeks. Liraglutide 0.9 mg was statistically superior to all DPP-4 interventions (vildagliptin, sitagliptin, linagliptin, alogliptin, teneligliptin, trelagliptin and omarigliptin) at 12 weeks and 24 weeks among those reporting. Treatments were not statistically differentiable with respect to weight change and risk of hypoglycemia. Finally, no comparisons of eGFR and microalbuminuria were conducted, as this data was reported in too few trials to conduct analyses.

LIMITATIONS

Some important outcomes were limited by poor reporting (eGFR and microalbuminuria) or low event rates (hypoglycemia). The follow-up time was relatively short. Clinically, the 24 week time point is more important as it demonstrates more sustained results.

CONCLUSIONS

Our research suggests that liraglutide 0.9 mg offers a more efficacious treatment option for T2DM than the DPP-4 inhibitors among adult Japanese patients and that it is a viable option for this population.

A Randomized, Placebo-Controlled Trial Evaluating the Safety and Efficacy of Adding Omarigliptin to Antihyperglycemic Therapies in Japanese Patients with Type 2 Diabetes and Inadequate Glycemic Control

INTRODUCTION

Daily dipeptidyl peptidase-4 (DPP-4) inhibitors are commonly used with other orally administered antihyperglycemic agents (AHA), as combination therapy, to treat Japanese patients with type 2 diabetes. When combination therapy is indicated, use of a once-weekly (q.w.) orally administered DPP-4 inhibitor might be an appropriate therapeutic option for some patients.

METHODS

A 52-week trial was conducted to assess the safety and tolerability (primary objectives) and glycemic efficacy (secondary objectives) of the q.w. DPP-4 inhibitor omarigliptin as add-on therapy to five different classes of orally administered AHA [sulfonylurea (SU), glinide (GL), biguanide (BG), thiazolidinedione (TZD), or α-glucosidase inhibitor (AGI)] commonly used in Japan and having different mechanisms of drug action from DPP-4 inhibitors. The trial consisted of an initial 24-week double-blind, placebo-controlled period during which patients (stratified by background AHA) were randomized to omarigliptin 25 mg q.w. or placebo, followed by a 28-week open-label period during which patients on placebo were switched to omarigliptin.

RESULTS

After 24 weeks, the percentages of patients with adverse events (AEs), serious AEs, drug-related AEs, AEs of symptomatic hypoglycemia, or who discontinued from trial medication because of an AE were generally similar in the omarigliptin and placebo groups, in all background AHA strata and in the overall population. From a mean baseline HbA1c of approximately 8.0%, the placebo-adjusted least-squares mean changes from baseline ranged from -0.80% (AGI stratum) to -1.16% (TZD stratum); p < 0.001 for all background AHA strata. During the open-label period, no safety signals emerged with longer-term treatment. At week 52, the change from baseline in HbA1c in the omarigliptin/omarigliptin group was similar to that of the placebo/omarigliptin group.

CONCLUSIONS

Addition of once-weekly omarigliptin to AHA therapy with an SU, GL, BG, TZD, or AGI for up to 52 weeks was generally safe and well tolerated, and provided persistent efficacy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT01697592.

FUNDING

MSD K.K., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.

Cardiovascular Safety of Dipeptidyl-Peptidase IV Inhibitors: A Meta-Analysis of Placebo-Controlled Randomized Trials

BACKGROUND

Large randomized trials have shown conflicting evidence regarding the cardiovascular safety of dipeptidyl-peptidase 4 (DPP-4) inhibitors. Systematic reviews have been limited by incomplete data and inclusion of observational studies. This study aimed to systematically evaluate the cardiovascular safety of DPP-4 inhibitors in patients with type 2 diabetes.

METHODS

Electronic databases were searched for randomized trials that compared DPP-4 inhibitors versus placebo and reported cardiovascular outcomes. The main outcome assessed in this analysis was heart failure. Other outcomes included all-cause mortality, cardiovascular mortality, myocardial infarction, and ischemic stroke. Summary odds ratios (ORs) were primarily constructed using Peto's model.

RESULTS

A total of 90 trials with 66,730 patients were included. Compared with placebo, DPP-4 inhibitors were associated with a non-significant increased risk of heart failure [OR 1.11, 95% confidence interval (CI) 0.99-1.25, P = 0.07] at a mean of 108 weeks. The risk of all-cause mortality (OR 1.03, 95% CI 0.94-1.12, P = 0.53), cardiovascular mortality (OR 1.02, 95% CI 0.92-1.14, P = 0.72), myocardial infarction (OR 0.98, 95% CI 0.88-1.09, P = 0.69), and ischemic stroke (OR 0.99, 95% CI 0.85-1.15, P = 0.92) was similar between both groups.

CONCLUSION

In patients with type 2 diabetes, the safety profile of DPP-4 inhibitors is similar to placebo. As a class, there is only weak evidence for an increased risk of heart failure.

Differential HbA1c response in the placebo arm of DPP-4 inhibitor clinical trials conducted in China compared to other countries: a systematic review and meta-analysis

BACKGROUND

It has been observed that the efficacy of dipeptidyl peptidase-4 (DPP-4) inhibitors as compared to the placebo groups in some clinical trials conducted in China is weaker than that in trials conducted outside China, leading to the suspicion that this may be caused by differential Glycosylated Hemoglobin (HbA1c) response in the placebo arm of DPP-4 inhibitor clinical trials conducted in China compared to other countries.

METHODS

We searched published articles and other documents related to phase III placebo-control trials of DPP-4 inhibitors in Type 2 diabetes mellitus (T2DM). We included studies from different countries and compared those conducted in China to those conducted in other countries. Meta-regression analysis was used to analyze the HbA1c response in the placebo arms.

RESULTS

A total of 66 studies met the inclusion criteria and 10 were conducted within China. There were a total of 8303 participants (mean age 56, male 57 %) in placebo groups. The pooled change in HbA1c for the placebo groups of 10 trials conducted in patients with T2DM in China was 0.26 % (95 % CI [-0.36 %, -0.16 %], p-value < 0.001), compared to 0.015 % (95 % CI [-0.05 %, 0.08 %], p-value is 0.637) for 56 trials conducted outside of China. The difference of placebo effect between trials conducted in and outside China is -0.273 % (95 % CI [-0.42 %, -0.13 %], p-value is less than 0.001) while after excluding trials conducted in Japan, the difference is -0.203 % (95 % CI [-0.35 %, -0.06 %], p-value is 0.005). They are both statistically significant.

CONCLUSIONS

The meta-analysis in the article demonstrates that there is statistically significant difference in the HbA1c response in the placebo arm of DPP-4 inhibitor clinical trials conducted in China compared to other countries. This differential HbA1c response in the placebo arm should be taken into consideration by both experimenters and medical decision makers when future DPP-4 studies are conducted in China.

Safety and efficacy of addition of sitagliptin to rapid-acting insulin secretagogues for glycemic control, including post-prandial hyperglycemia, among Japanese with type 2 diabetes mellitus

The safety and efficacy of sitagliptin as add-on therapy to glinides, rapid-acting insulin secretagogues, were evaluated for Japanese patients with type 2 diabetes mellitus. This 52-week study consisted of a 12-week double-blind period, followed by a 40-week open-label period. During the double-blind period, patients were randomized to sitagliptin 50 mg q.d. (S/S group) or placebo (P/S group) as add-on therapy to glinide monotherapy. During the open-label period, all patients in both groups were administered sitagliptin 50 mg q.d. (or 100 mg q.d. after up-titration). During the double-blind period, the overall occurrence of adverse experiences (AE) was similar in both treatment groups. The frequency of reported AE of hypoglycemia in both groups was low and not notably different. The nature of clinical AE during the open-label period for both groups was not notably different from that of clinical AE in the sitagliptin group during the double-blind period. The between-group difference in HbA1c least squares (LS) mean of change from baseline (95 % CI) at Week 12 was -1.1 % (-1.3, -0.8) in favor of sitagliptin (P < 0.001). LS mean of reductions from baseline of fasting plasma glucose and 2-h postmeal glucose were significantly greater in the sitagliptin group than in the placebo group: -23.1 mg/dL (-32.2, -13.9) and -51.2 mg/dL (-67.4, -35.0), respectively (both P < 0.001). The changes from baseline in glycemic data in the S/S group remained generally stable throughout the 52-week treatment period.

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.

Sitagliptin: a review of its use in patients with type 2 diabetes mellitus

Sitagliptin (Januvia(®), Xelevia™, Glactiv(®), Tesavel(®)) is an orally administered, potent and highly selective inhibitor of dipeptidyl peptidase-4 (DPP-4) and was the first agent of its class to be approved for use in the management of adults with type 2 diabetes. Numerous randomized placebo- or active comparator-controlled trials have demonstrated the efficacy of sitagliptin in terms of improving glycaemic control in patients with type 2 diabetes, including its use as monotherapy, initial combination therapy (usually with fixed-dose combinations of sitagliptin/metformin), or add-on therapy to metformin or to other antihyperglycaemic drugs, with or without metformin. The primary endpoint of the clinical trials was the reduction from baseline in glycosylated haemoglobin (HbA1c), although sitagliptin also showed beneficial effects for other endpoints, such as the proportion of patients who achieved target HbA1c, and reductions from baseline in fasting plasma glucose (FPG) levels and 2-h postprandial glucose (PPG) levels. Sitagliptin was generally well tolerated in clinical trials, had a low risk of hypoglycaemia (although this depends on background therapy) and had a neutral effect on body weight. Despite concerns regarding a possible increased risk of rare pancreatic adverse events (e.g. pancreatitis) with glucagon-like peptide-1 (GLP-1)-based therapies, such as GLP-1 receptor agonists and DPP-4 inhibitors, no causal association has been found; regulators in Europe recently conducted a review of available data, concluding that there is little evidence that these drugs could cause pancreatic inflammation or pancreatic cancer. A similar review is planned in the USA and postmarketing surveillance will continue. Thus, oral sitagliptin is an effective and generally well tolerated treatment option for the management of patients with type 2 diabetes.

Sitagliptin added to voglibose monotherapy improves glycemic control in patients with type 2 diabetes

AIMS/INTRODUCTION

Type 2 diabetes mellitus is a progressive disease that frequently requires patients to use more than one oral antihyperglycemic agent to achieve adequate glycemic control. The present multicenter, randomized study assessed the efficacy and safety of the addition of sitagliptin to ongoing voglibose monotherapy (0.2-0.3 mg three times daily) in Japanese patients with type 2 diabetes mellitus who had inadequate glycemic control (glycated hemoglobin ≥6.9% and <10.5%).

MATERIALS AND METHODS

The present study had an initial 12-week, double-blind treatment period in which patients were randomized (1:1) to sitagliptin 50 mg/day (n = 70) or placebo (n = 63), followed by a 40-week, open-label treatment period during which all patients received sitagliptin 50 mg/day, that could have been increased to 100 mg/day for patients meeting predefined glycemic criteria.

RESULTS

After 12 weeks, treatment with sitagliptin resulted in placebo-subtracted mean changes from baseline in glycated hemoglobin (the primary end-point), fasting plasma glucose and 2-h postmeal glucose of -0.9%, -22.5 mg/dL and -51.3 mg/dL, respectively (all, P < 0.001). During the double-blind period, adverse experiences were reported with similar frequency in both treatment groups, and the occurrences of hypoglycemia and gastrointestinal adverse experiences were low. In the open-label period, sustained improvements in glycemic parameters were observed with sitagliptin treatment, and sitagliptin was generally well tolerated.

CONCLUSIONS

Sitagliptin added on to ongoing voglibose monotherapy provided significant improvements in glycemic parameters and was well tolerated in Japanese patients with type 2 diabetes mellitus who had inadequate glycemic control. This trial was registered with ClinicalTrials.gov (no. NCT00837577).

Differences in the glucose-lowering efficacy of dipeptidyl peptidase-4 inhibitors between Asians and non-Asians: a systematic review and meta-analysis

AIMS/HYPOTHESIS

The aim of this work was to compare the glucose-lowering efficacy of dipeptidyl peptidase-4 (DPP-4) inhibitors between Asian and non-Asian patients with type 2 diabetes.

METHODS

We searched MEDLINE, EMBASE, LILACS, CENTRAL, ClinicalTrials.gov and conference proceedings. Studies were eligible if they were randomised controlled trials with a treatment duration of at least 12 weeks, compared a DPP-4 inhibitor with a placebo as either monotherapy or oral combination therapy, had information on ethnicity and HbA1c values and were published or described in English. A systematic review and meta-analysis with a meta-regression analysis was conducted.

RESULTS

Among 809 potentially relevant studies, 55 trials were included. A meta-analysis revealed that DPP-4 inhibitors lowered HbA1c to a greater extent in studies with ≥50% Asian participants (weighted mean difference [WMD] -0.92%; 95% CI -1.03, -0.82) than in studies with <50% Asian participants (WMD -0.65%; 95% CI -0.69, -0.60). The between-group difference was -0.26% (95% CI -0.36, -0.17, p < 0.001). The baseline BMI significantly correlated with the HbA1c-lowering efficacy of DPP-4 inhibitors. The RR of achieving the goal of HbA1c <7.0% (53.0 mmol/mol) was higher in studies with ≥50% Asian participants (3.4 [95% CI 2.6, 4.7] vs 1.9 [95% CI 1.8, 2.0]). The fasting plasma glucose-lowering efficacy was higher with monotherapy in the Asian-dominant studies, but the postprandial glucose-lowering efficacy and changes in body weight were comparable between the two groups.

CONCLUSIONS/INTERPRETATION

DPP-4 inhibitors exhibit a better glucose-lowering efficacy in Asians than in other ethnic groups; this requires further investigation to understand the underlying mechanism, particularly in relation to BMI.

Add-on therapy with the DPP-4 inhibitor sitagliptin improves glycemic control in insulin-treated Japanese patients with type 2 diabetes mellitus

The effect of add-on therapy with sitagliptin on glycemic control was prospectively investigated in patients with type 2 diabetes mellitus (T2DM) receiving insulin alone or insulin combined with oral antidiabetic drugs. Seventy-one patients were evaluated (38 men and 33 women aged 63.9 ± 10.2 years). They were divided into three groups, which were 45 patients receiving premixed insulin twice daily, 15 patients receiving multiple daily insulin injections, and 11 patients receiving basal insulin with oral antidiabetic drugs (basal insulin therapy). Concomitant oral drugs included sulfonylureas, α-glucosidase inhibitors and metformin. The hemoglobin A1c (HbA1c) of all patients improved significantly from 8.1 ± 1.2% to 7.6 ± 1.1% after 12 weeks of add-on therapy with sitagliptin (p<0.01), and the insulin dosage was reduced from 27.3 ± 15.8 U/day to 24.5 ± 16.5 U/day (p<0.001). Body weight did not change after the start of concomitant therapy and severe hypoglycemia was not observed. The baseline HbA1c and glycated albumin levels were identified as factors that predicted the response to add-on therapy with sitagliptin. These findings suggest that add-on therapy with sitagliptin can be expected to achieve improvement of poor glycemic control irrespective of a patient's demographic profile. Stratified analysis based on the insulin regimen revealed a stronger antidiabetic effect and a high efficacy of sitagliptin when it was added to basal insulin therapy. The results of this investigation confirmed that add-on therapy with sitagliptin to various insulin regimens could improve glycemic control without severe hypoglycemia and/or weight gain.

Efficacy and safety of alogliptin added to metformin in Japanese patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial with an open-label, long-term extension study

AIMS

To evaluate the efficacy and safety of alogliptin added to metformin versus metformin monotherapy in Japanese patients with type 2 diabetes who achieved inadequate glycaemic control on metformin (500 or 750 mg/day) + diet/exercise.

METHODS

In a randomized, double-blind trial, 288 patients with type 2 diabetes mellitus T2DM received either 12.5 or 25 mg alogliptin once daily + metformin or placebo + metformin for 12 weeks. Thereafter, 276 patients continued on one of the two alogliptin dosages + metformin in an open-label extension for 40 weeks. The primary efficacy endpoint in the randomized, double-blind phase was the change in HbA1c from baseline (week 0) to the end of treatment (week 12). The primary endpoint during the long-term extension phase was adverse events.

RESULTS

After 12 weeks both dosages of alogliptin + metformin produced significantly greater changes from baseline in HbA1c than placebo (metformin monotherapy: with changes in LS means - 0.55 and - 0.64% vs. 0.22%, respectively; p < 0.0001). Incidences of adverse effects were comparable between groups, with no increases in hypoglycaemia. Over 52 weeks, there were no safety or tolerability concerns with alogliptin when added to metformin.

CONCLUSIONS

Alogliptin 12.5 and 25 mg once daily was safe and effective when added to metformin (500 or 750 mg/day) in Japanese patients with inadequately controlled type 2 diabetes on metformin alone.

Effects of 6-month sitagliptin treatment on glucose and lipid metabolism, blood pressure, body weight and renal function in type 2 diabetic patients: a chart-based analysis

Background

Sitagliptin is one of the dipeptidyl peptidase-4 (DPP-4) inhibitors which prevent the inactivation of incretins, increasing the endogenous active incretin levels. Incretins stimulate insulin secretion from pancreatic β-cells and inhibit glucagon secretion from pancreatic α-cells, which is favorable for the treatment of diabetes. Sitagliptin is released on December, 2009, in Japan. We retrospectively studied effects of 6-month-treatment with sitagliptin on glucose and lipid metabolism, blood pressure, body weight and renal function in patients with type 2 diabetes by a chart-based analysis.

Methods

We retrospectively studied 220 type 2 diabetic patients who have taken sitagliptin for 6 months by a chart-based analysis. Subjects studied include patients treated with sitagliptin monotherapy, sitagliptin add-on therapy, and switching from glinide to sitagliptin. We selected patients who have both data before and after 6-month sitagliptin treatment and compared the data before the sitagliptin treatment with the data at 6 month after the sitagliptin treatment started. Body weight, blood pressure, plasma glucose, hemoglobin A1c (HbA1c), serum lipids, and estimated glomerular filtration rate in type 2 diabetic patients were measured almost at the same time points before and after 6-month-treatment with sitagliptin.

Results

Body weight was significantly reduced after 6-month sitagliptin treatment by 0.8 kg. HbA1c levels were also significantly decreased after the sitagliptin treatment by 0.6%. We found a significant and negative correlation between change in body weight and body mass index at baseline. We also observed a significant and negative correlation between change in HbA1c and HbA1c levels at baseline. The number of patients who showed the absence of urinary glucose was significantly increased after the sitagliptin treatment.

Effects of 6-month sitagliptin treatment on glucose and lipid metabolism, blood pressure, body weight and renal function in type 2 diabetic patients: a chart-based analysis

BACKGROUND

Sitagliptin is one of the dipeptidyl peptidase-4 (DPP-4) inhibitors which prevent the inactivation of incretins, increasing the endogenous active incretin levels. Incretins stimulate insulin secretion from pancreatic β-cells and inhibit glucagon secretion from pancreatic α-cells, which is favorable for the treatment of diabetes. Sitagliptin is released on December, 2009, in Japan. We retrospectively studied effects of 6-month-treatment with sitagliptin on glucose and lipid metabolism, blood pressure, body weight and renal function in patients with type 2 diabetes by a chart-based analysis.

METHODS

We retrospectively studied 220 type 2 diabetic patients who have taken sitagliptin for 6 months by a chart-based analysis. Subjects studied include patients treated with sitagliptin monotherapy, sitagliptin add-on therapy, and switching from glinide to sitagliptin. We selected patients who have both data before and after 6-month sitagliptin treatment and compared the data before the sitagliptin treatment with the data at 6 month after the sitagliptin treatment started. Body weight, blood pressure, plasma glucose, hemoglobin A1c (HbA1c), serum lipids, and estimated glomerular filtration rate in type 2 diabetic patients were measured almost at the same time points before and after 6-month-treatment with sitagliptin.

RESULTS

Body weight was significantly reduced after 6-month sitagliptin treatment by 0.8 kg. HbA1c levels were also significantly decreased after the sitagliptin treatment by 0.6%. We found a significant and negative correlation between change in body weight and body mass index at baseline. We also observed a significant and negative correlation between change in HbA1c and HbA1c levels at baseline. The number of patients who showed the absence of urinary glucose was significantly increased after the sitagliptin treatment.