Vildagliptin add-on to metformin produces similar efficacy and reduced hypoglycaemic risk compared with glimepiride, with no weight gain: results from a 2-year study

Efficacy and Safety of DPP-4 Inhibitors and Metformin Combinations in Type 2 Diabetes: A Systematic Literature Review and Network Meta-Analysis

Objective

Several oral antidiabetic regimens are available for treating type 2 diabetes mellitus (T2DM), dipeptidyl peptidase-4 inhibitors (DPP4i) being one of them. We conducted a network meta-analysis (NMA) comparing DPP4i plus metformin (Met) combination with other Met-based oral antidiabetic drug (OAD) combinations used in treating patients with T2DM.

Methods

We searched PubMed and Embase from inception until 19th April, 2022 for phase II and phase III trials in patients with T2DM on Met-based traditional OADs. The primary outcome was assessed by change in glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and 2-hour post-prandial blood glucose (2h-PPG). The secondary safety outcomes assessed were hypoglycemic events, serious adverse events (SAEs), cardiovascular (CV) events, and gastrointestinal (GI) events.

Results

Sixty-two trials were included in the analysis. The combination of DPP4i + Met revealed a comparable mean reduction in HbA1c levels to the glinides (Gli) + Met combination (mean difference [MD]: -0.03%, 95% CI: 0.69, -0.65), although the difference was not statistically significant. The mean HbA1c reduction with DPP4i + Met was greater than with sulfonylureas (SU) + Met (MD: -0.05, 95% CI: -0.29, 0.39), thiazolidinedione (TZD) + Met (MD: -0.69, 95% CI: -1.39, -0.02), and SU + TZD (MD: 0.21; 95% CI: -1.30, 1.71), with no statistical significance. DPP4i + Met demonstrated a non-significant lower incidence of CV events in comparison to TZD + Met (RR: 1.01, 95% CI: 0.46, 2.45) and SU + Met (RR: 1.06, 95% CI: 0.61, 2.06).

Conclusion

DPP4i in combination with Met was efficacious and had a well-tolerated safety profile compared with other traditional OADs. This combination can be considered as a suitable treatment option for patients with T2DM.

The combination of berberine and isoliquiritigenin synergistically improved adipose inflammation and obesity-induced insulin resistance

White adipose tissue accumulation and inflammation contribute to obesity by inducing insulin resistance. Herein, we aimed to screen the synergistic components of the herbal pair Coptidis Rhizoma-Glycyrrhizae Radix et Rhizoma for the treatment of insulin resistance and explore the potential synergistic mechanisms. Enzyme-linked immunosorbent assay and quantitative PCR were used to detect expression levels of inflammatory genes in vitro and in vivo. Western blotting and immunohistochemistry were performed to detect protein levels of the insulin signaling pathway and macrophage markers. The effects on obesity-induced insulin resistance were verified using a diet-induced obesity (DIO) mouse model. Interactions between macrophage and adipocyte were assessed using a cellular supernatant transfer assay. Berberine (BBR) and isoliquiritigenin (ISL) alleviated mRNA levels and secretion of inflammatory genes in vitro and in vivo. Furthermore, BBR acted synergistically with ISL to ameliorate obesity and dyslipidemia in DIO mice. Meanwhile, the combination treatment significantly improved glucose intolerance and insulin resistance and decreased M1-macrophage accumulation and infiltration in the adipose tissue. Mechanistically, co-treatment with BBR and ISL upregulated the protein expression of the IRS1-PI3K-Akt insulin signaling pathway, enhanced glucose uptake in adipocyte, and suppressed the interaction between macrophage and adipocyte. BBR and ISL were identified as the synergistic components of the herbal pair Coptidis Rhizoma-Glycyrrhizae Radix et Rhizoma for treating insulin resistance. The synergistic combination of BBR with ISL can be a promising and effective strategy for improving obesity-induced adipose inflammation and insulin resistance.

Newer Pharmacologic Treatments in Adults With Type 2 Diabetes: A Systematic Review and Network Meta-analysis for the American College of Physicians

BACKGROUND

Newer diabetes medications may have beneficial effects on mortality, cardiovascular outcomes, and renal outcomes.

PURPOSE

To evaluate the effectiveness, comparative effectiveness, and harms of sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucagon-like peptide-1 (GLP1) agonists, dipeptidyl peptidase-4 (DPP4) inhibitors, and long-acting insulins as monotherapy or combination therapy in adults with type 2 diabetes mellitus (T2DM).

DATA SOURCES

MEDLINE and EMBASE for randomized controlled trials (RCTs) published from 2010 through January 2023.

STUDY SELECTION

RCTs lasting at least 52 weeks that included at least 500 adults with T2DM receiving eligible medications and reported any outcomes of interest.

DATA EXTRACTION

Data were abstracted by 1 reviewer and verified by a second. Independent, dual assessments of risk of bias and certainty of evidence (CoE) were done.

DATA SYNTHESIS

A total of 130 publications from 84 RCTs were identified. CoE was appraised using GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria for direct, indirect, and network meta-analysis (NMA); the highest CoE was reported. Compared with usual care, SGLT2 inhibitors and GLP1 agonists reduce all-cause mortality (high CoE) and major adverse cardiovascular events (MACE) (moderate to high CoE), SGLT2 inhibitors reduce progression of chronic kidney disease (CKD) and heart failure hospitalizations and GLP1 agonists reduce stroke (high CoE), and SGLT2 inhibitors reduce serious adverse events and severe hypoglycemia (high CoE). The threshold for minimally important differences, which was predefined with the American College of Physicians Clinical Guidelines Committee, was not met for these outcomes. Compared with usual care, insulin, tirzepatide, and DPP4 inhibitors do not reduce all-cause mortality (low to high CoE). Compared with insulin, SGLT2 inhibitors and GLP1 agonists reduce all-cause mortality (low to moderate CoE). Compared with DPP4 inhibitors, GLP1 agonists reduce all-cause mortality (moderate CoE). Compared with DPP4 inhibitors and sulfonylurea (SU), SGLT2 inhibitors reduce MACE (moderate to high CoE). Compared with SU and insulin, SGLT2 inhibitors and GLP1 agonists reduce severe hypoglycemia (low to high CoE).

LIMITATIONS

Infrequent direct comparisons between drugs of interest; sparse data for NMA on most outcomes; possible incoherence due to differences in baseline patient characteristics and usual care; insufficient data on predefined subgroups, including demographic subgroups, patients with prior cardiovascular disease, and treatment-naive persons.

CONCLUSION

In adults with T2DM, SGLT2 inhibitors and GLP1 agonists (but not DPP4 inhibitors, insulin, or tirzepatide) reduce all-cause mortality and MACE compared with usual care. SGLT2 inhibitors reduce CKD progression and heart failure hospitalization and GLP1 agonists reduce stroke compared with usual care. Serious adverse events and severe hypoglycemia are less frequent with SGLT2 inhibitors and GLP1 agonists than with insulin or SU.

PRIMARY FUNDING SOURCE

American College of Physicians. (PROSPERO: CRD42022322129).

Safety of dipeptidyl peptidase-4 inhibitors in older adults with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials

Registration:

PROSPERO: CRD42020210645

Introduction:

We aimed to assess the safety of dipeptidyl peptidase-4 (DPP-4) inhibitors in older patients with type 2 diabetes with inadequate glycaemic control.

Methods:

We included randomized controlled trials (RCTs) in older (⩾65 years) patients with type 2 diabetes. The intervention group was randomized to treatment with any DPP-4 inhibitors. A systematic search in MEDLINE and Embase was performed in December 2020. For assessing the risk of bias, RoB 2 tool was applied. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. We pooled outcomes using random effects meta-analyses.

Results:

We identified 16 RCTs that included 19,317 patients with a mean age of greater than 70 years. The mean HbA1c level ranged between 7.1 and 10.0 g/dl. Adding DPP-4 inhibitors to standard care alone may increase mortality slightly [risk ratio (RR) 1.04; 95% confidence interval (CI) 0.89–1.21]. Adding DPP-4 inhibitors to standard care increases the risk for hypoglycaemia (RR 1.08; 95% CI 1.01–1.16), but difference in overall adverse events is negligible. DPP-4 inhibitors added to standard care may reduce mortality compared with sulfonylureas (RR 0.88; 95% CI 0.75–1.04). DPP-4 inhibitors probably reduce the risk for hypoglycaemia compared with sulfonylureas (magnitude of effect not quantifiable because of heterogeneity) but difference in overall adverse events is negligible. There is insufficient evidence on hospitalizations, falls, fractures, renal impairment and pancreatitis.

Conclusion:

There is no evidence that DPP-4 inhibitors in addition to standard care decrease mortality but DPP-4 inhibitors increase hypoglycaemia risk. Second-line therapy in older patients should be considered cautiously even in drugs with a good safety profile such as DPP-4 inhibitors. In case second-line treatment is necessary, DPP-4 inhibitors appear to be preferable to sulfonylureas.

Plain language summary

Safety of dipeptidyl peptidase-4 inhibitors in older adults with type 2 diabetes Introduction: We performed the review to assess the safety of dipeptidyl peptidase-4 (DPP-4) inhibitors in older type 2 diabetes patients with blood sugar outside the normal level. Methods: To answer the question, we searched various electronic databases. We included studies in older (⩾65 years) patients with type 2 diabetes that assessed the safety of DPP-4 inhibitors. The data from the different studies were quantitatively summarized using statistical methods. We assessed the quality of the data to judge the certainty of the findings. Results: We identified 16 studies that included 19,317 patients with a mean age greater than 70 years. The average blood sugar level of patients in the included studies was slightly or moderately increased. Adding DPP-4 inhibitors to standard care alone may increase mortality slightly. Adding DPP-4 inhibitors to standard care increases the risk for hypoglycaemia, but difference in overall adverse events is negligible. DPP-4 inhibitors added to standard care may reduce mortality compared with sulfonylureas. DPP-4s probably reduce the risk of hypoglycaemia compared with sulfonylureas (magnitude of effect not quantifiable because of heterogeneity) but difference in overall adverse events is negligible. There is insufficient evidence on hospitalizations, falls, fractures, renal impairment and pancreatitis. Conclusion: There is no evidence that DPP-4 inhibitors in addition to standard care decrease mortality but DPP-4 inhibitors increase the risk that blood sugar falls below normal. Adding DPP-4 inhibitorss to standard care in older patients should be considered cautiously even in drugs with a good safety profile such as DPP-4 inhibitors. In case additional treatment is necessary, DPP-4 inhibitors appear to be preferable to sulfonylureas.

Pharmacokinetics and Bioequivalence of a Generic Fixed-Dose Combination Tablet of Metformin Hydrochloride/Vildagliptin Versus a Branded Product in Healthy Chinese Subjects Under Fed and Fasting Conditions

The purpose of this study was to compare the bioequivalence and safety of test and reference preparations of fixed-dose combination tablets of metformin hydrochloride/vildagliptin 850 mg/50 mg in healthy volunteers under fasting and fed conditions for marketing authorization in China. A single-dose, randomized, open-label, 2-way crossover study was conducted. Blood samples were collected up to 36 hours after dosing in each period with a 7-day washout. Pharmacokinetic parameters, including maximum plasma concentration (C_max ), time to reach C_max , area under the plasma concentration-time curve (AUC) from time 0 to the last time point of the measurable concentration, AUC from time 0 to infinity, terminal elimination half-life, and apparent clearance, were calculated using noncompartmental methods and compared between the 2 formulations. Safety profiles were assessed, including significant findings of vital signs, electrocardiogram, laboratory tests, physical examination, and adverse events. A total of 30 healthy subjects (19 men, 11 women) were randomized, and 29 subjects were treated under fasting conditions. Likewise, 30 subjects (24 men, 6 women) were randomized and treated under fed conditions. The geometric mean ratio and corresponding 90% confidence intervals of C_max , AUC from time 0 to the last time point of the measurable concentration , and AUC from time 0 to infinity for both metformin hydrochloride and vildagliptin between the 2 fixed-dose combination formulations were within the bioequivalence acceptance range of 80% to 125% under fasting or fed conditions. Therefore, the generic and branded formulations were bioequivalent and well tolerated in healthy Chinese subjects.

Cardiovascular Outcomes Comparison of Dipeptidyl Peptidase-4 Inhibitors versus Sulfonylurea as Add-on Therapy for Type 2 Diabetes Mellitus: a Meta-Analysis

Objective

Recent studies have raised concern about the cardiovascular safety of dipeptidyl peptidase-4 (DPP4) inhibitors. We performed a systematic review through meta-analysis to compare cardiovascular outcomes of sulfonylurea (SU) versus DPP4 inhibitors when used in combination with metformin.

Methods

After searching for trials using combination therapy of metformin with DPP4 inhibitor or SU in PubMed, Cochrane Library, and Embase, one prospective observation study and 15 randomized controlled studies were selected.

Results

Regarding the primary analysis endpoint, there were no significant differences in the risk of all-cause mortality between SU and DPP4 inhibitors as an add-on therapy to metformin (random-effect relative risk [RR], 1.14; 95% confidence interval [CI], 0.98–1.33; p=0.811; I²=0%). Cardiovascular death was also similar between the two drug classes in the five studies which reported outcomes (random-effect RR, 1.03; 95% CI, 0.83–1.27; p=0.517; I²=0%). Furthermore, there were no significant differences in major adverse cardiac events (MACE), coronary heart disease, myocardial infarction, ischemic stroke and heart failure. However, there were less hypoglycemic events and weight gain in the DPP4 inhibitor group as compared with the SU group (random-effect RR, 3.79; 95% CI, 1.53–9.39; p<0.001; I²=98.2 and weighted mean difference, 1.68; 95% CI, 1.07–2.29; p<0.001; I²=94.7, respectively).

Conclusion

As add-on therapy to metformin, there were no significant differences in all-cause mortality and cardiovascular mortality between DPP4 inhibitors and SUs.

Comparative clinical study evaluating the effect of adding Vildagliptin versus Glimepiride to ongoing Metformin therapy on diabetic patients with symptomatic coronary artery disease

BACKGROUND AND OBJECTIVE

Cardiovascular diseases (CVDs) remain the most identified cause of death in patients with diabetes mellitus (DM). This study aimed to evaluate the effect of adding Vildagliptin versus Glimepiride to ongoing Metformin on the biomarkers of inflammation, thrombosis, and atherosclerosis in T2DM patients with symptomatic coronary artery disease (CAD).

METHODS

This study included 80 patients with uncontrolled T2DM and symptomatic CAD who were randomized to add either Vildagliptin 50 mg/day "group I" or Glimepiride 4 mg/day "group II" to ongoing Metformin therapy (1000 mg/day). Blood samples were collected at baseline and 3 months after intervention for biochemical analysis of HbA1c %, IL-1β, adiponectin, hsCRP and lipid profile. Additionally atherogenic index (AI) and coronary risk index (CRI) were determined.

RESULTS

Three months after intervention and as compared to group II (Glimepiride/Metformin), group 1 (Vildagliptin/Metformin) showed significantly lower BMI (28.73 ± 3.48 versus 30.55 ± 3.15; p = 0.02), HbA1c (6.05 ± 0.72 versus 7.06 ± 0.89; p < 0.0001), hsCRP (0.96 ± 0.20 versus 1.72 ± 0.38; p < 0.0001), IL-1β (34.95 ± 10.01 versus 45.13 ± 10.26; p < 0.0001), TC (136 ± 23.45 versus 169 ± 35.72; p < 0.0001), TG (116 ± 29.10 versus 146 ± 56.58; p = 0.005), and CRI (2.47 ± 0.90 versus 3.65 ± 1.19; p < 0.0001) which was associated with significantly higher adiponectin and HDL-C (4.42 ± 1.29 versus 2.52 ± 1.86; p < 0.0001 and 61 ± 23.04 versus 48 ± 12.92; p = 0.003 respectively).

CONCLUSION

In patients with T2DM and symptomatic CAD, the addition of Vildagliptin to ongoing metformin showed better glycemic control, lower inflammatory markers (IL-1β and hsCRP), higher protective markers (adiponectin and HDL-C) and improved lipid profile compared to Glimepiride/metformin therapy.

Evaluating the Evidence behind the Novel Strategy of Early Combination from Vision to Implementation

Type 2 diabetes mellitus (T2DM) is a complex and progressive chronic disease characterised by elevating hyperglycaemia and associated need to gradually intensify therapy in order to achieve and maintain glycaemic control. Treating hyperglycaemia with sequential therapy is proposed to allow holistic assessment of the efficacy and risk-to-benefit ratio of each added component. However, there is an array of evidence supporting the scientific rationale for using synergistic, earlier, modern drug combinations to achieve glycaemic goals, delay the deterioration of glycaemic control, and, therefore, potentially preserve or slow down the declining β-cell function. Additionally, implementation of early combination(s) may lead to opportunities to combat clinical inertia and other hurdles to optimised disease management outcomes. This review aims to discuss the latest empirical evidence for long-term clinical benefits of this novel strategy of early combination in people with newly diagnosed T2DM versus the current widely-implemented treatment paradigm, which focuses on control of hyperglycaemia using lifestyle interventions followed by sequentially intensified (mostly metformin-based) monotherapy. The recent reported Vildagliptin Efficacy in combination with metfoRmin For earlY treatment of T2DM (VERIFY) study results have provided significant new evidence confirming long-term glycaemic durability and tolerability of a specific early combination in the management of newly diagnosed, treatment-naïve patients worldwide. These results have also contributed to changes in clinical treatment guidelines and standards of care while clinical implementation and individualised treatment decisions based on VERIFY results might face barriers beyond the existing scientific evidence.

Metabolic effects of antihyperglycemic agents and mortality: meta-analysis of randomized controlled trials

The effects of antihyperglycemic medications on cardiovascular events and mortality are heterogeneous and their effects on intermediate factors might explain these differences. This systematic review explores the relationship between metabolic factors, mechanism of action, and mortality effects of antihyperglycemic medications in type 2 diabetes. Randomized trials assessing the effects of antihyperglycemic medications on all-cause or cardiovascular mortality in type 2 diabetes were included. Myocardial infarction, stroke, and heart failure were secondary outcomes. The effects of medications on HbA1c, severe hypoglycemia (SH), body weight, systolic blood pressure (SBP), and mechanism of action were evaluated. Meta-analyses and meta-regressions were performed grouping studies according to the above-cited factors. All-cause mortality was lower for medications that reduced HbA1c, SH, body weight, and SBP. Decreased cardiovascular mortality was associated with lower HbA1c, SH, SBP. Myocardial infarction and stroke were also associated with favorable metabolic profile. These findings were not confirmed in meta-regression models. Medications associated with lower SH, body weight and SBP had a lower risk of heart failure. In conclusion, medications with better metabolic profile were associated with reduced all-cause and cardiovascular mortality. These findings are based on indirect comparisons and must be applied cautiously.

Effectiveness, safety, and tolerability of vildagliptin or vildagliptin/metformin combination in patients with type 2 diabetes uncontrolled on insulin therapy in a real-world setting in Egypt: The OMEGA study

PURPOSE

To evaluate the effectiveness and safety of vildagliptin or vildagliptin/metformin combination among patients with type 2 diabetes mellitus (T2DM) uncontrolled on insulin in a real-world setting in Egypt.

METHODS

This 12-week, prospective, observational study enrolled T2DM patients. Primary endpoint was mean change in glycated hemoglobin (HbA1c) from baseline to Week 12. Secondary endpoints included mean change in body weight, insulin dosage and safety after 12 weeks.

RESULTS

Of the 90 patients enrolled, 88 (93.6%) completed the study. The mean age was 54.7 years; men, 51.1%; body mass index (BMI), 31.6 kg/m²; T2DM duration, 89.8 months; insulin dose, 55.14 IU/day. At 12 weeks, HbA1c decreased significantly with vildagliptin/metformin (-1.3 ± 0.9%, p < 0.0001) and vildagliptin (-1.1 ± 0.9%, p = 0.0001). 27.1% and 11.1% achieved HbA1c <7% in vildagliptin/metformin and vildagliptin groups, respectively. Significant mean (±standard deviation [SD]) reduction in body weight (-2.5 ± 7.3 kg, p = 0.0055) and insulin dose (-24.11 ± 22.3 IU, p < 0.0001) was observed in the vildagliptin/metformin group. Overall, 8 (8.9%) patients reported 11 (12.2%) adverse events (AEs) and no hypoglycemic events. AEs possibly related to the study drug (4.2%, in vildagliptin/metformin) were mild in severity.

CONCLUSION

Vildagliptin with/without metformin as an add-on to insulin resulted in good glycemic control and was well tolerated without any hypoglycemic events.

Glycaemic durability of an early combination therapy with vildagliptin and metformin versus sequential metformin monotherapy in newly diagnosed type 2 diabetes (VERIFY): a 5-year, multicentre, randomised, double-blind trial

BACKGROUND

Early treatment intensification leading to sustained good glycaemic control is essential to delay diabetic complications. Although initial combination therapy has been suggested to offer more opportunities than a traditional stepwise approach, its validity remains to be determined.

METHODS

Vildagliptin Efficacy in combination with metfoRmIn For earlY treatment of type 2 diabetes (VERIFY) was a randomised, double-blind, parallel-group study of newly diagnosed patients with type 2 diabetes conducted in 254 centres across 34 countries. The study consisted of a 2-week screening visit, a 3-week metformin-alone run-in period, and a 5-year treatment period, which was further split into study periods 1, 2, and 3. Patients aged 18-70 years were included if they had type 2 diabetes diagnosed within 2 years prior to enrolment, and centrally confirmed glycated haemoglobin A1c (HbA_1c) of 48-58 mmol/mol (6·5-7·5%) and a body-mass index of 22-40 kg/m². Patients were randomly assigned in a 1:1 ratio either to the early combination treatment group or to the initial metformin monotherapy group, with the help of an interactive response technology system and simple randomisation without stratification. Patients, investigators, clinical staff performing the assessments, and data analysts were masked to treatment allocation. In study period 1, patients received either the early combination treatment with metformin (stable daily dose of 1000 mg, 1500 mg, or 2000 mg) and vildagliptin 50 mg twice daily, or standard-of-care initial metformin monotherapy (stable daily dose of 1000 mg, 1500 mg, or 2000 mg) and placebo twice daily. If the initial treatment did not maintain HbA_1c below 53 mmol/mol (7·0%), confirmed at two consecutive scheduled visits which were 13 weeks apart, patients in the metformin monotherapy group received vildagliptin 50 mg twice daily in place of the placebo and entered study period 2, during which all patients received the combination therapy. The primary efficacy endpoint was the time from randomisation to initial treatment failure, defined as HbA_1c measurement of at least 53 mmol/mol (7·0%) at two consecutive scheduled visits, 13 weeks apart from randomisation through period 1. The full analysis set included patients who received at least one randomised study medication and had at least one post-randomisation efficacy parameter assessed. The safety analysis set included all patients who received at least one dose of randomised study medication. This study is registered with ClinicalTrials.gov, NCT01528254.

FINDINGS

Trial enrolment began on March 30, 2012, and was completed on April 10, 2014. Of the 4524 participants screened, 2001 eligible participants were randomly assigned to either the early combination treatment group (n=998) or the initial metformin monotherapy group (n=1003). A total of 1598 (79·9%) patients completed the 5-year study: 811 (81·3%) in the early combination therapy group and 787 (78·5%) in the monotherapy group. The incidence of initial treatment failure during period 1 was 429 (43·6%) patients in the combination treatment group and 614 (62·1%) patients in the monotherapy group. The median observed time to treatment failure in the monotherapy group was 36·1 (IQR 15·3-not reached [NR]) months, while the median time to treatment failure time for those receiving early combination therapy could only be estimated to be beyond the study duration at 61·9 (29·9-NR) months. A significant reduction in the relative risk for time to initial treatment failure was observed in the early combination treatment group compared with the monotherapy group over the 5-year study duration (hazard ratio 0·51 [95% CI 0·45-0·58]; p<0·0001). Both treatment approaches were safe and well tolerated, with no unexpected or new safety findings, and no deaths related to study treatment.

INTERPRETATION

Early intervention with a combination therapy of vildagliptin plus metformin provides greater and durable long-term benefits compared with the current standard-of-care initial metformin monotherapy for patients with newly diagnosed type 2 diabetes.

FUNDING

Novartis.

Comparison of the Effectiveness and Safety of Vildagliptin Add-On to Metformin Versus Other Oral Dual Antidiabetes Agents in Patients with Type 2 Diabetes: The China Prospective Diabetes Study

INTRODUCTION

The efficacy and safety of vildagliptin alone or with metformin is well established by randomized trials, but it is unknown whether it can be extrapolated to the real-world setting in Chinese patients with type 2 diabetes mellitus (T2DM). This study aimed to assess the effectiveness and safety of vildagliptin add-on to metformin versus dual oral antidiabetes drug (OAD), non-vildagliptin combination therapies in real-world Chinese patients with T2DM.

METHODS

The China Prospective Diabetes Study was a post-marketing, prospective, multicenter, observational, real-world study conducted in 52 centers. Patients inadequately controlled with OAD monotherapy and who initiated vildagliptin add-on to metformin (VM cohort) or two OADs other than vildagliptin (comparator cohort) were included for the present analysis. The composite primary endpoint was glycated hemoglobin (HbA1c) <  7% and without tolerability events (hypoglycemia, weight gain ≥ 3%, or discontinuation due to gastrointestinal events) at 12 months. Secondary endpoints included change in HbA1c from baseline, subgroup analysis, and tolerability. Propensity score matching analysis was performed to adjust for baseline covariates imbalance (body mass index (BMI) and HbA1c).

RESULTS

A total of 604 patients received VM and 670 received comparator therapy. Patients who received VM were younger, more obese, and had a higher baseline HbA1c and a shorter duration of T2DM. After propensity score matching, there were 530 patients per cohort. After 12-month treatment, the success rates of the composite primary endpoint were 50.9% and 33.0% in the VM and comparator cohorts, respectively (P < 0.001; odds ratio = 2.10, 95% confidence interval (CI) 1.64-2.70). Furthermore, the success rates of the composite endpoint were higher with VM across geographic area, BMI, and baseline HbA1c subgroups. Fewer tolerability events occurred in the VM cohort versus the comparator cohort (8.3% vs. 16.2%, P < 0.001; relative risk = 0.51, 95% CI 0.36-0.72).

CONCLUSION

Compared with dual OAD non-vildagliptin combination therapies, vildagliptin add-on to metformin is effective and safe to achieve glycemic control in Chinese patients with T2DM.

FUNDING

Novartis.

Metformin and second- or third-generation sulphonylurea combination therapy for adults with type 2 diabetes mellitus

BACKGROUND

The number of people with type 2 diabetes mellitus (T2DM) is increasing worldwide. The combination of metformin and sulphonylurea (M+S) is a widely used treatment. Whether M+S shows better or worse effects in comparison with other antidiabetic medications for people with T2DM is still controversial.

OBJECTIVES

To assess the effects of metformin and sulphonylurea (second- or third-generation) combination therapy for adults with type 2 diabetes mellitus.

SEARCH METHODS

We updated the search of a recent systematic review from the Agency for Healthcare Research and Quality (AHRQ). The updated search included CENTRAL, MEDLINE, Embase, ClinicalTrials.gov and WHO ICTRP. The date of the last search was March 2018. We searched manufacturers' websites and reference lists of included trials, systematic reviews, meta-analyses and health technology assessment reports. We asked investigators of the included trials for information about additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) randomising participants 18 years old or more with T2DM to M+S compared with metformin plus another glucose-lowering intervention or metformin monotherapy with a treatment duration of 52 weeks or more.

DATA COLLECTION AND ANALYSIS

Two review authors read all abstracts and full-text articles and records, assessed risk of bias and extracted outcome data independently. We used a random-effects model to perform meta-analysis, and calculated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the certainty of the evidence using the GRADE instrument.

MAIN RESULTS

We included 32 RCTs randomising 28,746 people. Treatment duration ranged between one to four years. We judged none of these trials as low risk of bias for all 'Risk of bias' domains. Most important events per person were all-cause and cardiovascular mortality, serious adverse events (SAE), non-fatal stroke (NFS), non-fatal myocardial infarction (MI) and microvascular complications. Most important comparisons were as follows:Five trials compared M+S (N = 1194) with metformin plus a glucagon-like peptide 1 analogue (N = 1675): all-cause mortality was 11/1057 (1%) versus 11/1537 (0.7%), risk ratio (RR) 1.15 (95% confidence interval (CI) 0.49 to 2.67); 3 trials; 2594 participants; low-certainty evidence; cardiovascular mortality 1/307 (0.3%) versus 1/302 (0.3%), low-certainty evidence; serious adverse events (SAE) 128/1057 (12.1%) versus 194/1537 (12.6%), RR 0.90 (95% CI 0.73 to 1.11); 3 trials; 2594 participants; very low-certainty evidence; non-fatal myocardial infarction (MI) 2/549 (0.4%) versus 6/1026 (0.6%), RR 0.57 (95% CI 0.12 to 2.82); 2 trials; 1575 participants; very low-certainty evidence.Nine trials compared M+S (N = 5414) with metformin plus a dipeptidyl-peptidase 4 inhibitor (N = 6346): all-cause mortality was 33/5387 (0.6%) versus 26/6307 (0.4%), RR 1.32 (95% CI 0.76 to 2.28); 9 trials; 11,694 participants; low-certainty evidence; cardiovascular mortality 11/2989 (0.4%) versus 9/3885 (0.2%), RR 1.54 (95% CI 0.63 to 3.79); 6 trials; 6874 participants; low-certainty evidence; SAE 735/5387 (13.6%) versus 779/6307 (12.4%), RR 1.07 (95% CI 0.97 to 1.18); 9 trials; 11,694 participants; very low-certainty evidence; NFS 14/2098 (0.7%) versus 8/2995 (0.3%), RR 2.21 (95% CI 0.74 to 6.58); 4 trials; 5093 participants; very low-certainty evidence; non-fatal MI 15/2989 (0.5%) versus 13/3885 (0.3%), RR 1.45 (95% CI 0.69 to 3.07); 6 trials; 6874 participants; very low-certainty evidence; one trial in 64 participants reported no microvascular complications were observed (very low-certainty evidence).Eleven trials compared M+S (N = 3626) with metformin plus a thiazolidinedione (N = 3685): all-cause mortality was 123/3300 (3.7%) versus 114/3354 (3.4%), RR 1.09 (95% CI 0.85 to 1.40); 6 trials; 6654 participants; low-certainty evidence; cardiovascular mortality 37/2946 (1.3%) versus 41/2994 (1.4%), RR 0.78 (95% CI 0.36 to 1.67); 4 trials; 5940 participants; low-certainty evidence; SAE 666/3300 (20.2%) versus 671/3354 (20%), RR 1.01 (95% CI 0.93 to 1.11); 6 trials; 6654 participants; very low-certainty evidence; NFS 20/1540 (1.3%) versus 16/1583 (1%), RR 1.29 (95% CI 0.67 to 2.47); P = 0.45; 2 trials; 3123 participants; very low-certainty evidence; non-fatal MI 25/1841 (1.4%) versus 21/1877 (1.1%), RR 1.21 (95% CI 0.68 to 2.14); P = 0.51; 3 trials; 3718 participants; very low-certainty evidence; three trials (3123 participants) reported no microvascular complications (very low-certainty evidence).Three trials compared M+S (N = 462) with metformin plus a glinide (N = 476): one person died in each intervention group (3 trials; 874 participants; low-certainty evidence); no cardiovascular mortality (2 trials; 446 participants; low-certainty evidence); SAE 34/424 (8%) versus 27/450 (6%), RR 1.68 (95% CI 0.54 to 5.21); P = 0.37; 3 trials; 874 participants; low-certainty evidence; no NFS (1 trial; 233 participants; very low-certainty evidence); non-fatal MI 2/215 (0.9%) participants in the M+S group; 2 trials; 446 participants; low-certainty evidence; no microvascular complications (1 trial; 233 participants; low-certainty evidence).Four trials compared M+S (N = 2109) with metformin plus a sodium-glucose co-transporter 2 inhibitor (N = 3032): all-cause mortality was 13/2107 (0.6%) versus 19/3027 (0.6%), RR 0.96 (95% CI 0.44 to 2.09); 4 trials; 5134 participants; very low-certainty evidence; cardiovascular mortality 4/1327 (0.3%) versus 6/2262 (0.3%), RR 1.22 (95% CI 0.33 to 4.41); 3 trials; 3589 participants; very low-certainty evidence; SAE 315/2107 (15.5%) versus 375/3027 (12.4%), RR 1.02 (95% CI 0.76 to 1.37); 4 trials; 5134 participants; very low-certainty evidence; NFS 3/919 (0.3%) versus 7/1856 (0.4%), RR 0.87 (95% CI 0.22 to 3.34); 2 trials; 2775 participants; very low-certainty evidence; non-fatal MI 7/890 (0.8%) versus 8/1374 (0.6%), RR 1.43 (95% CI 0.49 to 4.18; 2 trials); 2264 participants; very low-certainty evidence; amputation of lower extremity 1/437 (0.2%) versus 1/888 (0.1%); very low-certainty evidence.Trials reported more hypoglycaemic episodes with M+S combination compared to all other metformin-antidiabetic agent combinations. Results for M+S versus metformin monotherapy were inconclusive. There were no RCTs comparing M+S with metformin plus insulin. We identified nine ongoing trials and two trials are awaiting assessment. Together these trials will include approximately 16,631 participants.

AUTHORS' CONCLUSIONS

There is inconclusive evidence whether M+S combination therapy compared with metformin plus another glucose-lowering intervention results in benefit or harm for most patient-important outcomes (mortality, SAEs, macrovascular and microvascular complications) with the exception of hypoglycaemia (more harm for M+S combination). No RCT reported on health-related quality of life.

Baseline characteristics in the VERIFY study: a randomized trial assessing the durability of glycaemic control with early vildagliptin-metformin combination in newly diagnosed Type 2 diabetes

AIM

To assess the long-term clinical benefits of early combination treatment with vildagliptin-metformin vs. standard-of-care, metformin monotherapy in the ongoing VERIFY study.

METHODS

We randomized 2001 participants with multi-ethnic background, aged 18-70 years, having HbA_1c levels 48-58 mmol/mol (6.5-7.5%) and BMI 22-40 kg/m² . Baseline data included HbA_1c , fasting plasma glucose and homeostasis model β-cell and insulin sensitivity. Standardized meal-tests, insulin secretion rate relative to glucose, and oral glucose insulin sensitivity were assessed in a subpopulation.

RESULTS

Out of 4524 screened, data were collected from the 2001 eligible participants (53% women) across Europe (52.4%), Latin America (26.8%), Asia (17.2%), South Africa (3.1%) and Australia (0.5%). The median (interquartile range) disease duration was 3.4 (0.9, 10.2) months; mean (±SD) age 54.3±9.4 years; weight 85.5±17.5 kg and BMI 31.1±4.7 kg/m² . Baseline HbA_1c was 52±3 mmol/mol (6.9±0.3%), fasting plasma glucose 7.5±1.5 mmol/l and the median (interquartile range) of fasting insulin was 109 (75-160) mU/l. Homeostasis model β-cell and insulin sensitivity values were 84% (60, 116) and 46% (31, 68), respectively. In those undertaking meal-tests, insulin secretion rate relative to glucose was 28±12 pmol/min/m² /mmol/l and oral glucose insulin sensitivity was 353±57 ml/min/m² .

CONCLUSIONS

Our current, multi-ethnic, newly diagnosed VERIFY population reflects a characteristic presence of early insulin resistance in participants with increased demand for insulin associated with obesity. The VERIFY study will provide unique evidence in characterizing therapeutic intervention in a diverse population with hyperglycaemia, focusing on durability of early glycaemic control.

Comparative effect of saxagliptin and glimepiride with a composite endpoint of adequate glycaemic control without hypoglycaemia and without weight gain in patients uncontrolled with metformin therapy: Results from the SPECIFY study, a 48-week, multi-centre, randomized, controlled trial

AIMS

To compare the efficacy and safety of saxagliptin and glimepiride in type 2 diabetes (T2D) patients who are inadequately controlled with metformin monotherapy.

MATERIALS AND METHODS

In this 48-week, multi-centre, open-label, randomized, parallel trial (NCT02280486, clinicaltrials.gov), a total of 388 T2D patients were randomized 1:1 to saxagliptin or glimepiride groups. The primary endpoint was achievement of HbA1c <7.0%, without hypoglycaemia, defined as blood glucose <3.9 mmol/L and weight gain <3.0% after 48 weeks of treatment.

RESULTS

Over 48 weeks, a greater proportion of patients achieved the primary endpoint with saxagliptin compared with glimepiride (43.3% vs 31.3%; odds ratio, 1.38, 95% CI, 1.05-1.82; P = 0.019), especially among patients with baseline HbA1c <8.0%, duration <5 years or baseline BMI ≥25 kg/m² . Mean reduction in HbA1c was similar in the two treatment groups at Week 48 (-0.94% with saxagliptin vs -0.98% with glimepiride; P = 0.439). Bodyweight decreased with saxagliptin, but increased with glimepiride over the treatment period, and the treatment difference was -1.6 kg (P < 0.001) at Week 48. The proportion of patients experiencing hypoglycaemia was much lower with saxagliptin vs glimepiride (3.1% vs 12.8%; P < 0.001).

CONCLUSIONS

This study provides evidence that, compared to glimepiride, saxagliptin more effectively achieves a composite endpoint of adequate glycaemic control without hypoglycaemia and without weight gain in T2D patients who are inadequately controlled with metformin monotherapy, especially in overweight patients with moderate hyperglycaemia and a relatively short duration of diabetes.

A safety and tolerability profile comparison between dipeptidyl peptidase-4 inhibitors and sulfonylureas in diabetic patients: A systematic review and meta-analysis

BACKGROUND

The first treatment approach for type 2 diabetes mellitus is lifestyle change and metformin, but it is usually not sufficient. For some time, the anti-hyperglycemic classes of sulfonylureas and dipeptidyl peptidase-4 (DPP-4) inhibitors were considered second-line of treatment, since they show similar efficacy effect. However, the recent ADA-EASD consensus gives the preference to DPP-4 inhibitors compared to sulfonylureas, except if cost is a major problem. We performed a meta-analysis for safety and tolerability profile to comprehend which treatment has less adverse events.

METHODS

PUBMED and EMBASE databases were searched from inception until July 2017 to retrieve RCT studies comparing DPP-4 inhibitors and sulfonylureas treatments in adult type 2 diabetes patients. There was no language restriction. We extracted and combined data from studies comparison that reported safety profile and weight change. A random effect, meta-analytic model was applied to all calculations. Cochrane collaboration tool was used to assess quality and bias of the included studies. Trial registered with PROSPERO (CRD42017075823).

FINDINGS

Out of 1472 articles identified in our search and screened for eligibility, 36 studies comparing DPP-4 inhibitors and sulfonylureas were identified. DPP-4 inhibitors in combination with metformin had less overall adverse events (RR: 0·90; 95% CI, 0·86-0·94; p < 0·0001; I² = 83%; 17 studies), cardiovascular events (RR: 0·54; 95% CI, 0·37-0·79; p = 0·002; I² = 0%; 6 studies), hypoglycemia (RR: 0·17; 95% CI, 0·13-0·22; p < 0·00001; I² = 76%; 17 studies) and severe hypoglycemic events (RR: 0·10; 95% CI, 0·05-0·19; p < 0·00001; I² = 0%; 12 studies). The mean difference of the weight change was 1·92 kg in favor of DPP-4 inhibitors in combination with metformin in relation to sulfonylureas in combination with metformin. Monotherapy with DPP-4 inhibitors also had less rates of hypoglycemia (RR: 0·31; 95% CI, 0·24-0·41; p < 0·00001; I² = 0%; 8 studies) and severe hypoglycemic events (RR: 0·26; 95% CI, 0·10-0·66; p = 0·004; I² = 0%; 8 studies) and patients did not gain 1·19 kg.

INTERPRETATION

These results suggest better safety profile for DPP-4 inhibitors than sulfonylureas for both comparisons, and it is more notable when the treatment regimen includes metformin.

FUNDING

This study was funded by Takeda Pharmaceuticals, Brazil.

Effects of Sitagliptin on Pancreatic Beta-Cells in Type 2 Diabetes With Sulfonylurea Treatment: A Prospective Randomized Study

Background

This prospective randomized, multicenter, open-label, comparative study was performed to analyze the effects of sitagliptin on glycemic control and maintenance of beta-cell function in patients with poorly controlled type 2 diabetes treated with low-dose glimepiride.

Methods

Forty-one patients with type 2 diabetes mellitus treated with low-dose glimepiride (≤ 2 mg/day) were prospectively enrolled in this study (age: 20 - 75 years; hemoglobin A1c (HbA1c): 7.4- 9.4%). The patients were randomized into two groups: the glimepiride (G) group, in which glimepiride dose was increased gradually to 6 mg/day, and the sitagliptin (S) group, in which sitagliptin was added at a dose of 50 mg/day.

Results

HbA1c level was significantly decreased after 24 weeks, but not 12 weeks, in the G group, while a significant decrease was seen after 12 weeks in the S group. Although there were no significant differences in HbA1c level at 24 weeks between the two groups (P = 0.057). The overall trend of changes in HbA1c level suggested that the glucose-lowering effects were superior in the S group. Furthermore, a significant change in fasting glucose was seen in the S group, but not in the G group. Glycemic control target was achieved in 36.7% and 16.7% patients in the S group and the G group, respectively. The proinsulin/insulin (P/I) ratio was significantly increased in the G group, whereas it tended to decrease in the S group. After 24 weeks of treatment, no significant difference was observed in the P/I ratio between the two groups, whereas a significant difference was noted in the ΔP/I (amount of change). Albuminuria tended to increase in the G group compared with the S group.

Conclusion

The results of the present study suggested that sitagliptin effectively lowered hyperglycemia and that it may have a protective effect on pancreatic beta-cells when combined with a low dose of glimepiride. Therefore, sitagliptin may represent a useful combination therapy with low-dose sulfonylurea, not only for achieving glycemic control but also for protection of pancreatic beta-cells.

Clinical Use of DPP-4 Inhibitors

DPP-4 inhibitors were introduced for the treatment of type 2 diabetes in 2006. They stimulate insulin secretion and inhibit glucagon secretion by elevating endogenous GLP-1 concentrations without an intrinsic hypoglycaemia risk. Their efficacy potential to lower HbA1c is in the range between 0.5 and 1.0% and their safety profile is favorable. DPP-4 inhibitors are body weight neutral and they have demonstrated cardiovascular safety. Most compounds can be used in impaired renal function. Guidelines suggest the additional use of DPP-4 inhibitors after metformin failure in patients that do not require antidiabetic therapy with proven cardiovascular benefit. Recently, DPP-4 inhibitors have increasingly replaced sulfonylureas as second line therapy after metformin failure and many metformin/DPP-4 inhibitor fixed dose combinations are available. In later stages of type 2 diabetes, DPP-4 inhibitors are also recommended in the guidelines in triple therapies with metformin and SGLT-2 inhibitors or with metformin and insulin. A treatment with DPP-4 inhibitors should be stopped when GLP-1 receptor agonists are used. DPP-4 inhibitors can be used as monotherapy when metformin is contraindicated or not tolerated. Some studies have shown value of initial metformin-DPP-4 inhibitor combination therapy in special populations. This article gives an overview on the clinical use of DPP-4 inhibitors.

A randomized controlled trial to compare the effects of sulphonylurea gliclazide MR (modified release) and the DPP-4 inhibitor vildagliptin on glycemic variability and control measured by continuous glucose monitoring (CGM) in Brazilian women with type 2 diabetes

AIMS

This study aims to evaluate whether there is a difference between the effects of vildagliptin and gliclazide MR (modified release) on glycemic variability (GV) in women with type 2 diabetes (T2DM) as evaluated by continuous glucose monitoring (CGM).

METHODS

An open-label, randomized study was conducted in T2DM women on steady-dose metformin monotherapy which were treated with 50 mg vildagliptin twice daily or 60-120 mg of gliclazide MR once daily. CGM and GV indices calculation were performed at baseline and after 24 weeks.

RESULTS

In total, 42 patients (age: 61.9 ± 5.9 years, baseline glycated hemoglobin (HbA1c): 7.3 ± 0.56) were selected and 37 completed the 24-week protocol. Vildagliptin and gliclazide MR reduced GV, as measured by the mean amplitude of glycemic excursions (MAGE, p = 0.007 and 0.034, respectively). The difference between the groups did not reach statistical significance. Vildagliptin also significantly decreased the standard deviation of the mean glucose (SD) and the mean of the daily differences (MODD) (p = 0.007 and 0.030).

CONCLUSIONS

Vildagliptin and gliclazide MR similarly reduced the MAGE in women with T2DM after 24 weeks of treatment. Further studies are required to attest differences between vildagliptin and gliclazide MR regarding glycemic variability.

The Vildagliptin Experience - 25 Years Since the Initiation of the Novartis Glucagon-like Peptide-1 Based Therapy Programme and 10 Years Since the First Vildagliptin Registration

The discovery of the incretin hormone glucagon like peptide-1 (GLP-1), and its usefulness in the treatment of type 2 diabetes mellitus (T2DM) followed by the finding that dipeptidyl peptidase-4 (DPP-4) inhibition prevents GLP-1 inactivation, led to the discovery of DPP-728. In 1999, studies with DPP-728 established the first proof-of-concept that DPP-4 inhibition improves glycaemic control in patients with T2DM. Further efforts to improve the binding kinetics of DPP-728 resulted in the discovery of vildagliptin (LAF237). In the last 20 years, a plethora of studies conducted by Novartis in collaboration with external investigators has demonstrated the mechanism of action of vildagliptin and its efficacy as monotherapy and as an add-on therapy for patients with T2DM. The studies establish that vildagliptin is a selective DPP-4 inhibitor that blocks GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) inactivation, thereby prolonging their action, resulting in improved glycaemic control. This review aims to discuss the discovery and development of vildagliptin, with an emphasis on mechanism of action and clinical efficacy.

Direct head-to-head comparison of glycaemic durability of dipeptidyl peptidase-4 inhibitors and sulphonylureas in patients with type 2 diabetes mellitus: A meta-analysis of long-term randomized controlled trials

We performed a meta-analysis of randomized controlled trials (RCTs) to compare the long-term glycaemic durability of dipeptidyl-peptidase 4 (DPP-4) inhibitors vs that of sulphonylureas (SUs) in patients with type 2 diabetes mellitus (T2DM), in terms of the changes in glycated haemoglobin (HbA1c) levels from an intermediate time point (26 or 52 weeks) to 104 weeks of treatment. The Medline (PubMed), Embase (Ovid), and CENTER (Cochrane Library) databases were searched for relevant RCTs. Eight RCTs were included. Compared with SUs, DPP-4 inhibitors were associated with significantly smaller increases in the HbA1c level from 24 to 28 weeks to 104 weeks (mean difference [MD]: -0.16%, 95% confidence interval [CI]: -0.21 to -0.11; P < .001) and from 52 weeks to 104 weeks (MD -0.06%, 95% CI -0.10 to -0.02; P = .001). No significant heterogeneities were detected among the included comparisons (I²  = 0%). These results suggest that long-term treatment with DPP-4 inhibitors confers better durability of glycaemic response than treatment with SUs in patients with T2DM, which may indicate that DPP-4 inhibitors better preserve islet β-cell function compared with SUs.

Practical strategies for improving outcomes in T2DM: The potential role of pioglitazone and DPP4 inhibitors

T2DM is a complex disease underlined by multiple pathogenic defects responsible for the development and progression of hyperglycaemia. Each of these factors can now be tackled in a more targeted manner thanks to glucose-lowering drugs that have been made available in the past 2 to 3 decades. Recognition of the multiplicity of the mechanisms underlying hyperglycaemia calls for treatments that address more than 1 of these mechanisms, with more emphasis placed on the earlier use of combination therapies. Although chronic hyperglycaemia contributes to and amplifies cardiovascular risk, several trials have failed to show a marked effect from intensive glycaemic control. During the past 10 years, the effect of specific glucose-lowering agents on cardiovascular risk has been explored with dedicated trials. Overall, the cardiovascular safety of the new glucose-lowering agents has been proven with some of the trials summarized in this review, showing significant reduction of cardiovascular risk. Against this background, pioglitazone, in addition to exerting a sustained glucose-lowering effect, also has ancillary metabolic actions of potential interest in addressing the cardiovascular risk of T2DM, such as preservation of beta-cell mass and function. As such, it seems a logical agent to combine with other oral anti-hyperglycaemic agents, including dipeptidyl peptidase-4 inhibitors (DPP4i). DPP4i, which may also have a potential to preserve beta-cell function, is available as a fixed-dose combination with pioglitazone, and could, potentially, attenuate some of the side effects of pioglitazone, particularly if a lower dose of the thiazolidinedione is used. This review critically discusses the potential for early combination of pioglitazone and DPP4i.

Incretin-based therapy in type 2 diabetes: An evidence based systematic review and meta-analysis

Incretin based therapies such as dipeptidyl peptidase-4 inhibitors (DPP-4i) and glucagon-like peptide-1 receptor agonists (GLP-1Ra) are increasingly used for the treatment of Type 2 diabetes mellitus. In clinical practice and in previously performed clinical trials, these agents are often used in combination with other oral anti-diabetic agents (OADs) and Insulin. Prior meta-analytic reviews however do not adequately address the impact of background therapy and active comparator arms. Accordingly, we aimed to further investigate the efficacy of incretin based therapies by updating existing reviews by including clinical trial evidence after 2008; estimating the pooled effect of incretin therapies on glycemic efficacy and weight-loss, stratified by comparator therapy (placebo, mono-therapy, etc.), estimating the impact of background OADs and within class (GLP-1Ra or DPP-4i) comparative efficacy, on glycemia control. 82 randomized controlled trials after 2008 with glycemic control and weight loss as primary end-points were included. Both DPP-4i and GLP-1Ra reduced HbA1c, but only GLP-1Ra caused weight loss when compared to either active comparator drugs or placebo. GLP-1Ra were more effective than DPP-4i in glycemia lowering. Long acting GLP-1Ra were more effective in HbA1c lowering than short-acting agents but with similar weight loss effect. The effect of DPP-4i incretin glycemic efficacy was not modified by background therapy used in the study.

Network meta-analysis of lorcaserin and oral hypoglycaemics for patients with type 2 diabetes mellitus and obesity

In addition to weight loss, randomized controlled trials have shown improvement in glycaemic control in patients taking lorcaserin. The aim of this study aim was to compare adding lorcaserin or other glucose lowering medications to metformin on weight and glycaemic control. A systematic review and network meta-analysis of randomized controlled trials were conducted. Included studies (published 1990-2014) were of lorcaserin or glucose lowering medications in type 2 diabetic patients compared to placebo or different active treatments. Studies had to report ≥1 key outcome (change in weight or HbA1c, % HbA1c <7, hypoglycaemia). Direct meta-analysis was performed using DerSimonian and Laird random effects models, and network meta-analysis with Bayesian Markov-chain Monte Carlo random effects models; 6552 articles were screened and 41 included. Lorcaserin reduced weight significantly more than thiazolidinediones, glinides, sulphonylureas and dipeptidyl peptidase-4 inhibitors, some of which may have led to weight gain. There were no significant differences in weight change between lorcaserin and alpha-glucoside inhibitors, glucagon-like peptide-1 agonists and sodium/glucose cotransporter 2 inhibitors. Network meta-analysis showed lorcaserin was non-inferior to all other agents on HbA1c reduction and % achieving HbA1c of <7%. The risk of hypoglycaemia was not significantly different among studied agents except that sulphonylureas were associated with higher risk of hypoglycaemia than lorcaserin. Although additional studies are needed, this analysis suggests in a population of patients with a body mas index of ≥27 who do not achieve glycaemic control on a single agent, lorcaserin may be added as an alternative to an add-on glucose lowering medication.

Variability in and predictors of glycaemic responses after 24 weeks of treatment with exenatide twice daily and exenatide once weekly

The range of glycated haemoglobin (HbA1c) responses and characteristics associated with above-average response to exenatide twice daily and once weekly were examined. Data were pooled from 8 exenatide-twice-daily and 5 exenatide-once-weekly studies. A baseline HbA1c-corrected measure of change in HbA1c after 24 weeks identified high, average and low responses. Multiple linear regression and multivariate generalized estimating equation models identified factors associated with high response. Among 2355 participants (exenatide twice daily, n = 1414; exenatide once weekly, n = 941), baseline HbA1c correlated with change in HbA1c (P < .0001). Across baseline HbA1c levels, the 25th to 75th percentile of HbA1c change ranged from -0.3% to -3.2% with exenatide twice daily and from -0.5% to -3.6% with exenatide once weekly. Asian ethnicity and older age were significantly associated with high response to exenatide twice daily; no factors were significantly associated with response to exenatide once weekly. These data provide clinically useful information for estimating the likelihood that, depending on baseline HbA1c, an individual can achieve HbA1c goals. The association between Asian ethnicity, age and high response to exenatide twice daily may relate to the specific effects of exenatide twice daily on postprandial glucose.

Effectiveness and safety of dipeptidyl peptidase 4 inhibitors in the management of type 2 diabetes in older adults: a systematic review and development of recommendations to reduce inappropriate prescribing

Background

Preventable drug-related hospital admissions can be associated with drugs used in diabetes and the benefits of strict diabetes control may not outweigh the risks, especially in older populations. The aim of this study was to look for evidence on risks and benefits of DPP-4 inhibitors in older adults and to use this evidence to develop recommendations for the electronic decision support tool of the PRIMA-eDS project.

Methods

Systematic review using a staged approach which searches for systematic reviews and meta-analyses first, then individual studies only if prior searches were inconclusive. The target population were older people (≥65 years old) with type 2 diabetes. We included studies reporting on the efficacy and/or safety of DPP-4 inhibitors for the management of type 2 diabetes. Studies were included irrespective of DPP-4 inhibitors prescribed as monotherapy or in combination with any other drug for the treatment of type 2 diabetes. The target intervention was DPP-4 inhibitors compared to placebo, no treatment, other drugs to treat type 2 diabetes or a non-pharmacological intervention.

Results

Thirty studies (reported in 33 publications) were included: 1 meta-analysis, 17 intervention studies and 12 observational studies. Sixteen studies were focused on older adults and 14 studies reported subgroup analyses in participants ≥65, ≥70, or ≥75 years. Comorbidities were reported by 26 studies and frailty or functional status by one study. There were conflicting findings regarding the effectiveness of DPP-4 inhibitors in older adults. In general, DPP-4 inhibitors showed similar or better safety than placebo and other antidiabetic drugs. However, these safety data are mainly based on short-term outcomes like hypoglycaemia in studies with HbA1c control levels recommended for younger people. One recommendation was developed advising clinicians to reconsider the use of DPP-4 inhibitors for the management of type 2 diabetes in older adults with HbA1c <8.5% because of scarce data on clinically relevant benefits of their use. Twenty-two of the included studies were funded by pharmaceutical companies and authored or co-authored by employees of the sponsor.

Conclusions

Other than the surrogate endpoint of improved glycaemic control, data on clinically relevant benefits of DPP-4 inhibitors in the treatment of type 2 diabetes mellitus in older adults is scarce. DPP-4 inhibitors might have a lower risk of hypoglycaemia compared to other antidiabetic drugs but data show conflicting findings for long-term benefits. Further studies are needed that evaluate the risks and benefits of DPP-4 inhibitors for the management of type 2 diabetes mellitus in older adults, using clinically relevant outcomes and including representative samples of older adults with information on their frailty status and comorbidities. Studies are also needed that are independent of pharmaceutical company involvement.

Electronic supplementary material

The online version of this article (doi:10.1186/s12877-017-0571-8) contains supplementary material, which is available to authorized users.

Relationship Between Duration of Type 2 Diabetes and Effectiveness of DPP-4 Inhibitor Versus Sulfonylurea as Add-on Therapy: A Post Hoc Analysis

INTRODUCTION

To assess the impact of duration of type 2 diabetes on glucose-lowering effectiveness of the dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin versus sulfonylureas (SUs) in a real-life setting.

METHODS

Data were extracted from the large 1-year, observational EDGE study (N = 45,868). Patients receiving either DPP-4 inhibitor or any SU as add-on to monotherapy were selected (N = 36,164). Impact of the disease duration on change in glycated hemoglobin (HbA1c) levels was evaluated by using a linear multiple regression model. Descriptive statistics assessed the proportion of patients achieving the composite endpoint (HbA1c <7.0%; 53.0 mmol/mol without hypoglycemia or weight gain), stratified by diabetes duration.

RESULTS

At baseline, the overall mean (±SD) type 2 diabetes duration was 5.4 ± 5.24 years, and HbA1c was 8.2 ± 1.33% (66.0 ± 14.5 mmol/mol). HbA1c lowering was directly proportional to the baseline HbA1c (-0.69 per unit; 95% CI -0.696, -0.681; p < 0.0001) and inversely proportional to the disease duration (0.01 per year; 95% CI 0.01, 0.013). There was an increased loss of β-cell function (less pronounced HbA1c drop with increasing disease duration) in patients treated with SU-based regimens (0.025; 95% CI 0.022, 0.027) compared with vildagliptin-based regimens (0.005; 95% CI 0.003, 0.007), with the mean adjusted difference being 0.10 (95% CI -0.122, -0.092; p < 0.0001). Consistently, a higher proportion of patients achieved the composite endpoint with vildagliptin over the diabetes duration (less than 2 to more than 10 years).

CONCLUSION

Vildagliptin demonstrated less dependency on the duration of type 2 diabetes, whereas the effectiveness of SUs diminished faster with increasing duration of the disease in a real-life setting.

FUNDING

Novartis Pharma AG.

The efficacy and safety of adding either vildagliptin or glimepiride to ongoing metformin therapy in patients with type 2 diabetes mellitus

OBJECTIVE

To compare the effects of either vildagliptin or glimepiride on glycemic variability, oxidative stress, and endothelial parameters in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin alone.

METHODS

In this randomized, open-label, parallel study, 34 patients with T2DM being treated with metformin having an HbA1c of 7.0-10.0% were allocated into either the vildagliptin or glimepiride group. A mixed-meal tolerance test and 72-hour continuous glucose monitoring were conducted, and urinary 8-iso-prostaglandinF_2α (PGF_2α) and endothelial-dependent flow-mediated dilatation (FMD) were evaluated at baseline and after 12 weeks of treatment.

RESULTS

Similar significant improvements in HbA1c level were shown in both vildagliptin (-0.8%) and glimepiride (-0.9%) groups after treatment (Ps<0.001). The mean amplitude of glycemic excursions (MAGE) and the mean of daily differences (MODD) were significantly decreased by vildagliptin (P = 0.044 and P = 0.031, respectively) but not by glimepiride. Glimepiride was significantly associated with a higher incidence of hypoglycemia than vildagliptin (P = 0.005). There were no significant differences in urinary 8-iso-PGF_2α or FMD between the two groups.

CONCLUSIONS

Vildagliptin effectively improved glucose level with a significantly greater reduction in glycemic variability and hypoglycemia than glimepiride in patients with T2DM ongoing metformin therapy. The two drugs showed no significant differences in urinary 8-iso-PGF_2α and FMD.

TRIAL REGISTRATION

NCT01404676.

Effectiveness and safety of vildagliptin and vildagliptin add-on to metformin in real-world settings in Egypt - results from the GUARD study

OBJECTIVE

The GUARD study evaluated the effectiveness, safety, and tolerability of vildagliptin treatment with or without metformin in patients with type 2 diabetes mellitus (T2DM) in real-life settings. Here we present the results of the GUARD study for the patient subset from Egypt.

RESEARCH DESIGN AND METHODS

This was a 24 ± 6 weeks, prospective, non-interventional study that enrolled adult patients with T2DM receiving vildagliptin or vildagliptin + metformin combination therapy as per local prescribing information.

MAIN OUTCOME MEASURES

The primary effectiveness endpoint was change in HbA1c levels from baseline to week 24 ± 6 endpoint. Safety was assessed by reporting of adverse events and serious adverse events (SAEs).

RESULTS

Of 2786 patients enrolled from Egypt, 655 received vildagliptin and 2131 received vildagliptin + metformin. Overall, at baseline, mean (± standard deviation [SD]) age was 49.5 ± 9.49 years, BMI was 31.5 ± 4.85 kg/m², HbA1c was 8.4 ± 0.86%, and duration of T2DM was 2.3 ± 3.78 years. At week 24, significant reductions in mean (±SD) HbA1c were observed in the vildagliptin (-1.47 ± 0.79%) and vildagliptin + metformin (-1.62 ± 0.82%) groups (both p < 0.0001) from baseline HbA1c of 8.1% and 8.4%, respectively. At week 24, 67.5% patients in the vildagliptin group and 60.5% in the vildagliptin + metformin group achieved HbA1c ≤7.0%. Treatment with vildagliptin (± metformin) was well tolerated, with a low incidence of hypoglycemia in both groups (vildagliptin, 0.5%; vildagliptin + metformin, 0.6%). No SAEs or deaths were reported in the vildagliptin group; however, 0.2% of patients experienced SAEs and one death (accidental death) was reported in the vildagliptin + metformin group.

CONCLUSION

In a real-world setting, vildagliptin, with or without metformin, resulted in significant reductions in HbA1c and was well tolerated in patients with T2DM from Egypt. Limitations of the study include non-randomization and the open-label, observational nature of the study.

A systematic literature review on the efficacy-effectiveness gap: comparison of randomized controlled trials and observational studies of glucose-lowering drugs

Aim

To identify a potential efficacy–effectiveness gap and possible explanations (drivers of effectiveness) for differences between results of randomized controlled trials (RCTs) and observational studies investigating glucose-lowering drugs.

Methods

A systematic literature review was conducted in English language articles published between 1 January, 2000 and 31 January, 2015 describing either RCTs or observational studies comparing glucagon-like peptide-1 analogs (GLP-1) with insulin or comparing dipeptidyl peptidase-4 inhibitors (DPP-4i) with sulfonylurea, all with change in glycated hemoglobin (HbA1c) as outcome. Medline, Embase, Current Content, and Biosis were searched. Information on effect estimates, baseline characteristics of the study population, publication year, study duration, and number of patients, and for observational studies, characteristics related to confounding adjustment and selection- and information bias were extracted.

Results

From 312 hits, 11 RCTs and 7 observational studies comparing GLP-1 with insulin, and from 474 hits, 16 RCTs and 4 observational studies comparing DPP-4i with sulfonylurea were finally included. No differences were observed in baseline characteristics of the study populations (age, sex, body mass index, time since diagnosis of type 2 diabetes mellitus, and HbA1c) or effect sizes across study designs. Mean effect sizes ranged from −0.43 to 0.91 and from −0.80 to 1.13 in RCTs and observational studies, respectively, comparing GLP-1 with insulin, and from −0.13 to 2.70 and −0.20 to 0.30 in RCTs and observational studies, respectively, comparing DPP-4i and sulfonylurea. Generally, the identified observational studies held potential flaws with regard to confounding adjustment and selection- and information bias.

Conclusions

Neither potential drivers of effectiveness nor an efficacy–effectiveness gap were identified. However, the limited number of studies and potential problems with confounding adjustment, selection- and information bias in the observational studies, may have hidden a true efficacy-effectiveness gap.

The effect of vildagliptin relative to sulfonylurea as dual therapy with metformin (or as monotherapy) in Muslim patients with type 2 diabetes fasting during Ramadan in the Middle East: the VIRTUE study

OBJECTIVE

To assess the effect of vildagliptin relative to sulfonylurea (SU) on hypoglycemic events, in Muslim patients from the Middle East with type 2 diabetes who fast during Ramadan. The primary endpoint was the proportion of patients with at least one hypoglycemic event (HE) during the fasting period. Secondary endpoints included change in weight, HbA1c levels, treatment adherence and overall safety.

DESIGN AND METHODS

This multicenter, prospective, observational cohort study enrolled Muslim adult T2DM patients from Middle Eastern countries who received treatment with vildagliptin or SU as add on to metformin or monotherapy. During a ∼16 week observation period, data was collected up to 6 weeks before and 6 weeks after Ramadan fasting.

RESULTS

A total of 584 patients from the Middle East enrolled in the study; 308 patients received vildagliptin and 265 received SU. Significantly fewer vildagliptin patients reported at least one HE (3.7% vildagliptin vs. 25.5% SU; p < .001). No grade 2 HEs were reported in vildagliptin patients versus two in SU patients (p = .128). Mean change in HbA1c at the end of study showed -0.18% between treatment difference in favor of vildagliptin, p = .001. Mean body weight change at the end of study showed -0.68 kg between treatment difference in favor of vildagliptin, p < .001. Treatment exposure and adherence were high and similar in both cohorts. There were 4.3% adverse events reported in vildagliptin compared to 25.3% in the SU cohort, with hypoglycemia being the most experienced event in both cohorts.

LIMITATIONS

Being observational and not mandating HE confirmation with blood glucose measurement (though it was done in a large number of patients) were key limitations.

CONCLUSION

Anti-hyperglycemic treatment with vildagliptin led to significantly fewer hypoglycemia events compared to sulfonylurea treatment among Muslim diabetic patients who fast during Ramadan. Good glycemic control, weight control and safety results supported this outcome.

Pharmacology and therapeutic implications of current drugs for type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a global epidemic that poses a major challenge to health-care systems. Improving metabolic control to approach normal glycaemia (where practical) greatly benefits long-term prognoses and justifies early, effective, sustained and safety-conscious intervention. Improvements in the understanding of the complex pathogenesis of T2DM have underpinned the development of glucose-lowering therapies with complementary mechanisms of action, which have expanded treatment options and facilitated individualized management strategies. Over the past decade, several new classes of glucose-lowering agents have been licensed, including glucagon-like peptide 1 receptor (GLP-1R) agonists, dipeptidyl peptidase 4 (DPP-4) inhibitors and sodium/glucose cotransporter 2 (SGLT2) inhibitors. These agents can be used individually or in combination with well-established treatments such as biguanides, sulfonylureas and thiazolidinediones. Although novel agents have potential advantages including low risk of hypoglycaemia and help with weight control, long-term safety has yet to be established. In this Review, we assess the pharmacokinetics, pharmacodynamics and safety profiles, including cardiovascular safety, of currently available therapies for management of hyperglycaemia in patients with T2DM within the context of disease pathogenesis and natural history. In addition, we briefly describe treatment algorithms for patients with T2DM and lessons from present therapies to inform the development of future therapies.

Incretin-Based Therapy for Diabetes: What a Cardiologist Needs to Know

Incretin-based therapies are effective glucose-lowering drugs that have an increasing role in the treatment of type 2 diabetes because of their efficacy, safety, and ease of use. Both glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors are commonly used for glycemic control as adjuncts to metformin, other oral antiglycemic agents, or insulin. Glucagon-like peptide-1 receptor agonists may have additional effects, such as weight loss, that may be advantageous in obese patients. There is a large body of evidence from randomized controlled clinical trials supporting the cardiovascular safety of dipeptidyl peptidase-4 inhibitors and some glucagon-like peptide-1 receptor agonists, at least in the short term. However, concerns have been raised, particularly regarding their safety in patients with heart failure. In this review, the authors provide a brief but practical evidence-based analysis of the use of incretin-based agents in patients with diabetes, their efficacy, and cardiovascular safety.

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

INTRODUCTION

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Cardiovascular Effect of Incretin-Based Therapy in Patients with Type 2 Diabetes Mellitus: Systematic Review and Meta-Analysis

BACKGROUND

To assess the cardiovascular (CV) risk associated with the use of incretin-based therapy in adult patients with type 2 diabetes mellitus (T2DM) primary prevention group with low CV risks.

METHODS

The clinical studies on incretin-based therapy published in medical journals until August 2014 were comprehensively searched using MEDLINE, EMBASE and CENTRAL with no language restriction. The studies were systemically reviewed and evaluated for CV risks using a meta-analysis approach and where they meet the following criteria: clinical trial, incidence of predefined CV disease, T2DM with no comorbidities, age > 18 years old, duration of at least 12 weeks, incretin-based therapy compared with other antihyperglycaemic agents or placebo. Statistical analyses were performed using a Mantel-Haenszel (M-H) test. The odds ratios (OR) and their 95% confidence interval (CI) were estimated and displayed for comparison.

RESULTS

A total of 75 studies comprising 45,648 patients with T2DM were selected. The pooled estimate demonstrated no significance in decreased CV risk with incretin-based therapy versus control (M-H OR, 0.90; 95% CI, 0.81-1.00).

CONCLUSIONS

This meta-analysis suggests that incretin-based therapy show no significant protective effect on CV events in T2DM primary prevention group with low CV risks. Prospective randomized controlled trials are required to confirm the results of this analysis.

The Association between Sulfonylurea Use and All-Cause and Cardiovascular Mortality: A Meta-Analysis with Trial Sequential Analysis of Randomized Clinical Trials

BACKGROUND

Sulfonylureas are an effective and inexpensive treatment for type 2 diabetes. There is conflicting data about the safety of these drugs regarding mortality and cardiovascular outcomes. The objective of the present study was to evaluate the safety of the sulfonylureas most frequently used and to use trial sequential analysis (TSA) to analyze whether the available sample was powered enough to support the results.

METHODS AND FINDINGS

Electronic databases were reviewed from 1946 (Embase) or 1966 (MEDLINE) up to 31 December 2014. Randomized clinical trials (RCTs) of at least 52 wk in duration evaluating second- or third-generation sulfonylureas in the treatment of adults with type 2 diabetes and reporting outcomes of interest were included. Primary outcomes were all-cause and cardiovascular mortality. Additionally, myocardial infarction and stroke events were evaluated. Data were summarized with Peto odds ratios (ORs), and the reliability of the results was evaluated with TSA. Forty-seven RCTs with 37,650 patients and 890 deaths in total were included. Sulfonylureas were not associated with all-cause (OR 1.12 [95% CI 0.96 to 1.30]) or cardiovascular mortality (OR 1.12 [95% CI 0.87 to 1.42]). Sulfonylureas were also not associated with increased risk of myocardial infarction (OR 0.92 [95% CI 0.76 to 1.12]) or stroke (OR 1.16 [95% CI 0.81 to 1.66]). TSA could discard an absolute difference of 0.5% between the treatments, which was considered the minimal clinically significant difference. The major limitation of this review was the inclusion of studies not designed to evaluate safety outcomes.

CONCLUSIONS

Sulfonylureas are not associated with increased risk for all-cause mortality, cardiovascular mortality, myocardial infarction, or stroke. Current evidence supports the safety of sulfonylureas; an absolute risk of 0.5% could be firmly discarded.

REVIEW REGISTRATION

PROSPERO CRD42014004330.

A systematic review of the safety of incretin-based therapies in type 2 diabetes

INTRODUCTION

Large randomized clinical trials have demonstrated that incretin-based therapies provide effective glycemic control in type 2 diabetes. Long-term safety assessments are ongoing.

METHODS

This systematic review of incretin-based therapy safety is based on 112 randomized clinical trials of duration ≥26 weeks published between January 2000 and February 2015 in patients with type 2 diabetes.

RESULTS

As expected, hypoglycemia rates were lower with dipeptidyl peptidase-4 inhibitors (DPP-4is) and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) versus other oral antidiabetic drugs and insulin. The most common adverse events were infection and infestation (DPP-4is) and gastrointestinal (GLP-1 RAs). Pancreatitis cases were rare across all studies and, in the SAVOR-TIMI and EXAMINE trials, pancreatitis rates were similar in DPP-4i- and placebo-treated patients. No thyroid tumors were reported, and increased risk of cardiovascular events was not associated with DPP-4is in SAVOR-TIMI and EXAMINE, albeit over a short follow-up period.

CONCLUSIONS

Overall, incretin-based therapies were well tolerated; however, their long-term safety profile should continue to be periodically assessed.

Effects of vildagliptin relative to sulfonylureas in Muslim patients with type 2 diabetes fasting during Ramadan: influence of age and treatment with/without metformin in the VIRTUE study

BACKGROUND

VIRTUE was a prospective, observational study assessing the effectiveness and safety of vildagliptin vs sulfonylureas (SUs) (both as monotherapy and in combination with metformin) in patients with type 2 diabetes mellitus who fasted during Ramadan. A post hoc analysis was carried out to assess the effect of treatment with/without metformin and age (<65 years or ≥65 years).

PATIENTS AND METHODS

Patients were recruited from the Middle East and Asia. The primary end point was proportion of patients with one or more hypoglycemic event (HE) during Ramadan. Secondary end points included change from baseline in glycated hemoglobin (HbA1c), body weight, and safety.

RESULTS

Overall, 684 patients received vildagliptin and 631 received SUs. Most patients received dual therapy with metformin (n=1,148) and were aged <65 years (n=1,189). A few patients experienced one or more HE with vildagliptin vs SU monotherapy (6.5% vs 14.5%) and with vildagliptin + metformin vs SUs + metformin (5.3% vs 20.6%); the latter achieved statistical significance (P<0.001) in both age subgroups (<65 years: 5.5% vs 18.4%, P<0.001; ≥65 years: 2.8% vs 30.9%, P<0.001). Vildagliptin was associated with numerically greater HbA1c and body weight reductions vs SUs, regardless of the therapy type or age. A higher proportion of SU- vs vildagliptin-treated patients experienced adverse events across all subgroups.

CONCLUSION

A few patients experienced HEs with vildagliptin vs SUs regardless of age, and in patients on dual therapy. Vildagliptin ± metformin was also associated with good glycemic and weight control and was well tolerated. Vildagliptin might be a useful treatment option for patients with type 2 diabetes mellitus, particularly high-risk populations such as the elderly fasting during Ramadan.

Effects on Clinical Outcomes of Adding Dipeptidyl Peptidase-4 Inhibitors Versus Sulfonylureas to Metformin Therapy in Patients With Type 2 Diabetes Mellitus

BACKGROUND

Recent studies concluded that dipeptidyl peptidase-4 (DPP-4) inhibitors provide glycemic control but also raised concerns about the risk for heart failure in patients with type 2 diabetes mellitus (T2DM). However, large-scale studies of the effects on cardiovascular outcomes of adding DPP-4 inhibitors versus sulfonylureas to metformin therapy remain scarce.

OBJECTIVE

To compare clinical outcomes of adding DPP-4 inhibitors versus sulfonylureas to metformin therapy in patients with T2DM.

DESIGN

Nationwide study using Taiwan's National Health Insurance Research Database.

SETTING

Taiwan.

PATIENTS

All patients with T2DM aged 20 years or older between 2009 and 2012. A total of 10,089 propensity score-matched pairs of DPP-4 inhibitor users and sulfonylurea users were examined.

MEASUREMENTS

Cox models with exposure to sulfonylureas and DPP-4 inhibitors included as time-varying covariates were used to compare outcomes. The following outcomes were considered: all-cause mortality, major adverse cardiovascular events (MACEs) (including ischemic stroke and myocardial infarction), hospitalization for heart failure, and hypoglycemia. Patients were followed until death or 31 December 2013.

RESULTS

DPP-4 inhibitors were associated with lower risks for all-cause death (hazard ratio [HR], 0.63 [95% CI, 0.55 to 0.72]), MACEs (HR, 0.68 [CI, 0.55 to 0.83]), ischemic stroke (HR, 0.64 [CI, 0.51 to 0.81]), and hypoglycemia (HR, 0.43 [CI, 0.33 to 0.56]) compared with sulfonylureas as add-on therapy to metformin but had no effect on risks for myocardial infarction and hospitalization for heart failure.

LIMITATION

Observational study design.

CONCLUSION

Compared with sulfonylureas, DPP-4 inhibitors were associated with lower risks for all-cause death, MACEs, ischemic stroke, and hypoglycemia when used as add-ons to metformin therapy.

PRIMARY FUNDING SOURCE

None.

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.

Utility of Saxagliptin in the Treatment of Type 2 Diabetes: Review of Efficacy and Safety

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a complex disease in which multiple organs and hormones contribute to the pathogenesis of disease. The intestinal hormone, glucagon-like peptide-1 (GLP-1), secreted in response to nutrient ingestion, increases insulin secretion from pancreatic β-cells and reduces glucagon secretion from pancreatic α-cells. GLP-1 is inactivated by the dipeptidyl peptidase-4 (DPP-4) enzyme. Saxagliptin is a DPP-4 inhibitor that prevents the degradation of endogenous GLP-1 and prolongs its actions on insulin and glucagon secretion. This article reviews the efficacy and safety of saxagliptin in patients with T2DM.

METHODS

A PubMed literature search was conducted to identify relevant, peer-reviewed saxagliptin clinical trial articles published between January 2008 and June 2015. Search terms included "saxagliptin" and "DPP-4 inhibitors".

RESULTS

In clinical trials, saxagliptin significantly improved glycemic control when used as monotherapy or as add-on therapy to other antidiabetes agents and was associated with a low risk of hypoglycemia. In a large cardiovascular (CV) outcomes trial (SAVOR) in patients with T2DM and with established CV disease or multiple CV risk factors, saxagliptin neither increased nor decreased CV risk compared with placebo as assessed by the composite end point of death from CV causes, nonfatal myocardial infarction, or nonfatal stroke. Unexpectedly, more patients in the saxagliptin (3.5%) than in the placebo group (2.8%) were hospitalized for heart failure.

CONCLUSION

Saxagliptin demonstrated statistically significant and clinically meaningful improvements in glycemic control and a low risk of hypoglycemia in patients with T2DM. However, this positive profile needs to be tempered by the observation of an increased risk of hospitalization for heart failure in the SAVOR trial. Results from ongoing CV outcome trials with other DPP-4 inhibitors may provide additional data on how best to manage patients with T2DM who are at risk for heart failure.

FUNDING

AstraZeneca LP.

Long-term changes in cardiovascular risk markers during administration of exenatide twice daily or glimepiride: results from the European exenatide study

OBJECTIVE

The risk of cardiovascular morbidity and mortality is significantly increased in patients with diabetes; thus, it is important to determine whether glucose-lowering therapy affects this risk over time. Changes in cardiovascular risk markers were examined in patients with type 2 diabetes treated with exenatide twice daily (a glucagon-like peptide-1 receptor agonist) or glimepiride (a sulfonylurea) added to metformin in the EURopean EXenAtide (EUREXA) study.

RESEARCH DESIGN AND METHODS

Patients with type 2 diabetes failing metformin were randomized to add-on exenatide twice daily (n = 515) or glimepiride (n = 514) until treatment failure defined by hemoglobin A1C. Anthropomorphic measures, blood pressure (BP), heart rate, lipids, and high-sensitivity C-reactive protein (hsCRP) over time were evaluated.

RESULTS

Over 36 months, twice-daily exenatide was associated with improved body weight (-3.9 kg), waist circumference (-3.6 cm), systolic/diastolic BP (-2.5/-2.6 mmHg), high-density lipoprotein (HDL)-cholesterol (0.05 mmol/L), triglycerides (-0.2 mmol/L), and hsCRP (-1.7 mg/L). Heart rate did not increase (-0.3 beats/minute), and low-density lipoprotein-cholesterol (0.2 mmol/L) and total cholesterol (0.1 mmol/L) increased slightly. Between-group differences were significantly in favor of exenatide for body weight (P < 0.0001), waist circumference (P < 0.001), systolic BP (P < 0.001), diastolic BP (P = 0.023), HDL-cholesterol (P = 0.001), and hsCRP (P = 0.004). Fewer patients randomized to exenatide twice daily versus glimepiride required the addition of at least one antihypertensive (20.4 vs 26.4%; P = 0.026) or lipid-lowering medication (8.4 vs 12.8%; P = 0.025).

CONCLUSIONS

Add-on exenatide twice daily was associated with significant, sustained improvement in several cardiovascular risk markers in patients with type 2 diabetes versus glimepiride.

CLINICAL TRIAL REGISTRATION

NCT00359762, http://www.ClinicalTrials.gov.

Safety and efficacy of once-weekly dulaglutide versus sitagliptin after 2 years in metformin-treated patients with type 2 diabetes (AWARD-5): a randomized, phase III study

AIMS

To compare the once-weekly glucagon-like peptide-1 (GLP-1) receptor dulaglutide with the dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin after 104 weeks of treatment.

METHODS

This AWARD-5 study was a multicentre, double-blind trial that randomized participants to dulaglutide (1.5 or 0.75 mg) or sitagliptin 100 mg for 104 weeks or placebo (reported separately) for 26 weeks. Change in glycated haemoglobin (HbA1c) concentration from baseline was the primary efficacy measure. A total of 1098 participants with HbA1c concentrations ≥7.0% (≥53.0 mmol/mol) and ≤9.5% (≤80.3 mmol/mol) were randomized, and 657 (59.8%) completed the study. We report results for dulaglutide and sitagliptin at the final endpoint.

RESULTS

Changes in HbA1c at 104 weeks were (least squares mean ± standard error) -0.99 ± 0.06% (-10.82 ± 0.66 mmol/mol), -0.71 ± 0.07% (-7.76 ± 0.77 mmol/mol) and -0.32 ± 0.06% (-3.50 ± 0.66 mmol/mol) for dulaglutide 1.5 mg, dulaglutide 0.75 mg and sitagliptin, respectively (p < 0.001, both dulaglutide doses vs sitagliptin). Weight loss was greater with dulaglutide 1.5 mg (p < 0.001) and similar with 0.75 mg versus sitagliptin (2.88 ± 0.25, 2.39 ± 0.26 and 1.75 ± 0.25 kg, respectively). Gastrointestinal adverse events were more common with dulaglutide 1.5 and 0.75 mg versus sitagliptin (nausea 17 and 15% vs 7%, diarrhoea 16 and 12% vs 6%, vomiting 14 and 8% vs 4% respectively). Pancreatic, thyroid, cardiovascular and hypersensitivity safety were similar across groups.

CONCLUSIONS

Dulaglutide doses provided superior glycaemic control and dulaglutide 1.5 mg resulted in greater weight reduction versus sitagliptin at 104 weeks, with acceptable safety.

Efficacy and tolerability of vildagliptin as first line treatment in patients with diabetes type 2 in an outpatient setting

Background

Inhibitors of dipeptidyl-peptidase IV are recommended as second-line therapy in type 2 diabetes (DT2), but data, as a first-line treatment in everyday clinical practice are scarce. To address this issue we conducted a 12-month, clinical study in an outpatient setting, using vildagliptin as the first-line treatment.

Methods

Ninety-one drug naïve patients with DT2 started with vildagliptin monotherapy (100 mg daily) for 4 months and were scheduled to regular 4-monthly visits for 1 year. Patients received add-on treatment with metformin or metformin and glimepiride according to their glycosylated hemoglobin (HbA1c) at each study-visit.

Results

HbA1c was significantly decreased with vildagliptin monotherapy from 8.16 % ± 1.60 to 7.52 % ± 1.60, p < 0.001. Only 39 % of the patients achieved the target of HbA1c ≤ 7.0 % at the end of the 4th month. Mean change in HbA1c was significantly correlated with baseline HbA1c values (r = −0.51, p < 0.001). At the end of the study only 35 % of the patients remained on vildagliptin monotherapy while the rest required add-on treatment with metformin or metformin and sulfonylurea.

Conclusions

Vildagliptin is well tolerated either as monotherapy or in combination but the majority of patients require add-on therapy shortly after the beginning of treatment.

The efficacy and safety of DPP4 inhibitors compared to sulfonylureas as add-on therapy to metformin in patients with Type 2 diabetes: A systematic review and meta-analysis

There is no consensus on the selection of specific drug therapies when metformin fails in Type 2 diabetes (T2D). This meta-analysis was performed to determine the efficacy and safety of Dipeptidyl peptidase-4 inhibitors (DPP4-I) compared to sulfonylurea (SU) as add-on therapy to metformin in inadequately controlled T2D patients. We searched MEDLINE, CENTRAL, EMBASE, and CINAHL for randomized trials comparing DPP4-I to SU as add-on therapy to metformin and reported a change in hemoglobin A1c (HbA1c). Sixteen articles were included. There was a significantly greater reduction in HbA1c from baseline to 12 weeks with SU versus DPP4-I (MD[95% CI]=0.21%(2 mmol/mol) [0.06, 0.35]) but no significant difference at 52 and 104 weeks (MD[95% CI]=0.06%(-1 mmol/mol) [-0.03, 0.15] and 0.02%(-1 mmol/mol) [-0.13,0.18] respectively). SU was associated with weight gain and DPP4-I with weight loss at all time-points. The incidence of hypoglycemia at 12, 52, and 104 weeks was significantly greater with SU (20%, 24%, and 27% respectively) compared to DPP4-I (6%, 3%, and 4% respectively). The proportion of patients with HbA1c<7%(53 mmol/mol) without hypoglycemia was significantly higher at 52 and 104 weeks among patients on DPP4-I (RR[95% CI]=1.20 [1.05, 1.37] and 1.53 [1.16, 2.02] respectively). There was no significant difference between the two groups in the incidence of other side effects. While both SU and DPP4-I can be considered as options for add-on therapy to metformin in inadequately controlled T2D, SU results in a significantly increased risk of hypoglycemia and weight gain. By contrast, DPP4-I produce 0.4-0.6% (4-7 mmol/mol) reduction in HbA1c, lower risk of hypoglycemia, and weight loss.