Evaluate the effects of two dipeptidyl peptidase-IV (DPP-4) inhibitors, sitagliptin and vildagliptin, known to have different efficacy on mean amplitude of glycemic excursions (MAGE), on oxidative stress, and on systemic inflammatory markers in patients with type 2 diabetes.
RESEARCH DESIGN AND METHODS
A prospective, randomized, open-label PROBE design (parallel group with a blinded end point) study was performed in 90 patients with type 2 diabetes inadequately controlled by metformin. The study assigned 45 patients to receive sitagliptin (100 mg once daily; sitagliptin group) and 45 patients to receive vildagliptin (50 mg twice daily; vildagliptin group) for 12 weeks. MAGE, evaluated during 48 h of continuous subcutaneous glucose monitoring, allowed an assessment of daily glucose fluctuations at baseline and after 12 weeks in all patients. Assessment of oxidative stress (nitrotyrosine) and systemic levels of inflammatory markers interleukin (IL)-6 and IL-18 was performed at baseline and after 12 weeks in all patients.
HbA1c, fasting and postprandial glucose, MAGE, and inflammatory and oxidative stress markers were similar between the groups at baseline. After 12 weeks, MAGE (P < 0.01) was lower in the vildagliptin group than in the sitagliptin group. After treatment, HbA1c and postprandial glucose evidenced similar changes between the groups (P = NS). Vildagliptin treatment was associated with a stronger decrease in nitrotyrosine (P < 0.01), IL-6 (P < 0.05), and IL-18 (P < 0.05) than sitagliptin treatment. Nitrotyrosine and IL-6 changes significantly correlated with changes in MAGE but not in fasting glucose and HbA1c.
MAGE reduction is associated with reduction of oxidative stress and markers of systemic inflammation in type 2 diabetic patients. These effects were greater in the vildagliptin group than in the sitagliptin group.
We evaluated the effects of two dipeptidyl peptidase-4 (DPP-4) inhibitors, sitagliptin and vildagliptin, on metabolic parameters in patients with type 2 diabetes mellitus.
A total of 170 type 2 diabetes patients treated with sitagliptin or vildagliptin for more than 24 weeks were selected. The patients were separated into two groups, sitagliptin (100 mg once daily, n=93) and vildagliptin (50 mg twice daily, n=77). We compared the effect of each DPP-4 inhibitor on metabolic parameters, including the fasting plasma glucose (FPG), postprandial glucose (PPG), glycated hemoglobin (HbA1c), and glycated albumin (GA) levels, and lipid parameters at baseline and after 24 weeks of treatment.
The HbA1c, FPG, and GA levels were similar between the two groups at baseline, but the sitagliptin group displayed a higher PPG level (P=0.03). After 24 weeks of treatment, all of the glucose-related parameters were significantly decreased in both groups (P=0.001). The levels of total cholesterol and triglycerides were only reduced in the vildagliptin group (P=0.001), although the sitagliptin group received a larger quantity of statins than the vildagliptin group (P=0.002).The mean change in the glucose- and lipid-related parameters after 24 weeks of treatment were not significantly different between the two groups (P=not significant). Neither sitagliptin nor vildagliptin treatment was associated with a reduction in the high sensitive C-reactive protein level (P=0.714).
Vildagliptin and sitagliptin exert a similar effect on metabolic parameters, but vildagliptin exerts a more potent beneficial effect on lipid parameters.
Diabetes mellitus; DPP-4 inhibitor; Glycated serum albumin; Lipids
The oral DPP-4 inhibitors are new incretin-based therapies for treatment of type 2 diabetes. To assess the efficacy and safety of three DPP-4 inhibitors (Saxagliptin, Sitagliptin and Vildagliptin) as add-on therapy to dual combination of traditional oral hypoglycemic agents in Chinese type 2 diabetes patients.
In this 24-week, randomized, open-label, parallel clinical trial, we enrolled inadequately controlled (glycosylated haemoglobin A1c [HbA1c] ≥7.5% to ≤10%) patients with type 2 diabetes, who were treated by dual combination of metformin and another traditional oral hypoglycemic agent (glimepiride, acarbose or pioglitazone). 207 patients had been randomized to add-on 5 mg saxagliptin group or 100 mg sitagliptin once daily group, or 50 mg vildagliptin twice daily group for 24 weeks. HbA1c, fasting and postprandial blood glucose (FBG and P2hBG), body weight, body mass index (BMI), episodes of hypoglycemia and adverse events were evaluated.
After 24 weeks, HbA1c, FBG, and P2hBG of each group were significantly decreased. (saxagliptin vs vildagliptin vs sitagliptin: HbA1c: -1.2% vs -1.3% vs -1.1%; FBG: -1.8 mmol/l vs -2.4 mmol/l vs -1.5 mmol/l; P2hBG: -3.4 mmol/l vs -3.7 mmol/l vs -3.2 mmol/l). The changes of HbA1c and P2hBG among the three groups had no significance. However, vildagliptin-added group showed the greatest reduction (p < 0.001), while, sitagliptin-added group showed the lowest reduction (p < 0.001) in terms of FPG changes. Proportions of patients achieving HbA1c < 7% at the end were similar in three groups (saxagliptin 59%, vildagliptin 65%, sitagliptin 59%). Mild hypoglycemia was commonly reported among the three groups (saxagliptin 6%, vildagliptin 2%, sitagliptin 3%). No significant between-group difference was shown in other AEs.
The three gliptins showed almost similar glycemic control and incidence of adverse events. However, for FBG control, saxagliptin demonstrated superiority to sitagliptin, while, inferiority to vildagliptin.
Type 2 diabetes mellitus; Glycemic control; DPP-4 inhibitors; OHAs
We aimed to evaluate changes in insulin and glucagon secretion, as well as glucose levels, with a meal tolerance test (MTT) before and after 6 months of treatment with vildagliptin in a clinical setting.
Materials and Methods
Participants were 15 patients with uncontrolled type 2 diabetes mellitus (glycated hemoglobin [HbA1c] over 6.9 % for more than 3 months). MTTs were conducted before and 6 months after addition of vildagliptin (50 mg twice daily [bid]). Blood samples were collected immediately before, and 1 and 2 h after the test meal for measurement of blood glucose concentration, immune-reactive insulin (IRI), and glucagon. HbA1c was measured at 6 months.
Mean age of participants was 55.5 ± 2.8 years, and ten (66.7 %) were male. Mean HbA1c significantly improved from 7.6 to 6.8 % at 6 months after addition of vildagliptin. Blood glucose at 1 and 2 h after the test meal was significantly reduced after addition of vildagliptin, while the reduction in glucagon showed borderline significance and IRI showed no difference. In a comparison of blood glucose-related parameters between subgroups based on median glucose change in area under the curve during MTT (ΔAUC0–2h), glucagon ΔAUC0–2h was significantly lower in the group with more improved glucose levels (ΔAUC0–2h ≥65 mg/dL), but that of IRI did not differ.
Suppression of glucagon release by vildagliptin may improve glycemic control without increasing insulin levels in patients with type 2 diabetes.
AIM: To assess the effects of sitagliptin and nateglinide on lipid metabolism.
METHODS: In a parallel group comparative open trial, patients with type 2 diabetes mellitus under treatment at the Japanese Red Cross Medical Center were randomly assigned to receive either sitagliptin (50 mg once daily) or nateglinide (90 mg three times daily before meals). Eligible patients met the following criteria: age ≥ 20 years; hemoglobin A1c (HbA1c) > 6.5% despite diet and exercise; HbA1c between 6.5% and 8.0%; fasting glucose < 7.77 mmol/L; diet and exercise therapy for more than 3 mo; and ability to read and understand the information for written informed consent. Exclusion criteria were contraindications to sitagliptin, contraindications to nateglinide, pregnancy or possible pregnancy, and severe liver/renal failure. Patients who were considered to be unsuitable by the attending physician for other reasons were also excluded. Blood samples were collected at one and three hours after intake of a test meal. The primary outcome measure was the area under the curve (AUC) of apolipoprotein (Apo) B48 at three hours postprandially.
RESULTS: Twenty patients were randomly assigned to the sitagliptin group and sixteen patients were randomized to the nateglinide group. All 36 patients took the medication as directed by the physician in both groups, and they all were analyzed. Apart from antidiabetic drugs, there was no difference between the two groups with respect to the frequency of combined use of lipid-lowering, antihypertensive, and/or antiplatelet drugs. The doses of these medications were maintained during 12 wk of treatment. Detailed dietary advice, together with adequate exercise therapy, was given to the patients so that other factors apart from the two test drugs were similar in the two groups. There were no significant differences of the baseline characteristics between the two groups, except for body mass index (the sitagliptin group: 25.14 ± 3.05 kg/m2; the nateglinide group: 21.39 ± 2.24 kg/m2). Fasting levels of HbA1c, glycated albumin, 1.5-anhydroglucitol, and blood glucose, as well as the blood glucose levels at one and three hours postprandially, improved in both groups after 12 wk of treatment, and there were no significant differences between the two groups. However, the glucagon level at one hour postprandially (P = 0.040) and the diastolic blood pressure (P < 0.01) only showed a significant decrease in the sitagliptin group. In the nateglinide group, there was no significant change in the AUC of Apo B48, the glucagon level at one hour postprandially, the fasting triglyceride level, or the diastolic blood pressure. Body weight was unchanged in both groups. However, the AUC of Apo B48 at three hours postprandially showed a significant decrease in the sitagliptin group from 2.48 ± 0.11 at baseline to 1.94 ± 0.78 g/L per hour after 12 wk (P = 0.019). The fasting triglyceride level also decreased significantly in the sitagliptin group (P = 0.035). With regard to lipid-related markers other than Apo B48 and fasting triglycerides, no significant changes were observed with respect to Apo A1, Apo B, or Apo C3 in either group. No adverse events occurred in either group.
CONCLUSION: Sitagliptin significantly improves some lipid parameters while having a comparable effect on blood glucose to nateglinide. A large-scale prospective study of sitagliptin therapy is warranted.
Dipeptidyl-peptidase 4 inhibitors; Type 2 diabetes mellitus; Sitagliptin; Nateglinide; Blood glucose; Lipid metabolism
Saxagliptin, sitagliptin, and vildagliptin are dipeptidyl peptidase-4 (DPP-4) inhibitors widely approved for use in patients with type 2 diabetes. Using a crossover design, the present study compared trough levels of DPP-4 inhibition provided by these agents in a single cohort of patients with type 2 diabetes.
This was a randomized, placebo-controlled, open-label, five-period crossover study. Eligible patients were 18–65 years of age, either treatment-naïve or off prior antihyperglycemic agent therapy for at least 6 or 12 weeks (depending on the prior therapy), and had glycated hemoglobin (HbA1C) ≥6.5% and ≤10.0%. In separate study periods, patients received 5 mg saxagliptin q.d. (saxa-5), 100 mg sitagliptin q.d. (sita-100), 50 mg vildagliptin q.d. (vilda-50-q.d.), 50 mg vildagliptin b.i.d. (vilda-50-b.i.d.), or placebo for 5 days. The primary endpoint was trough %DPP-4 inhibition, derived by comparing DPP-4 activity 24 h after the Day-5 morning dose with predose activity in the same period and analyzed using a linear mixed-effects model with fixed-effects terms for treatment and period.
Mean (range) baseline HbA1C was 7.4% (6.4–9.0%; N = 22). Least-squares (LS) mean trough %DPP-4 inhibition was 73.5%, 91.7%, 28.9%, 90.6%, and 3.5% after saxa-5, sita-100, vilda-50-q.d., vilda-50-b.i.d., and placebo, respectively. In patients treated with sita-100, the LS-mean difference in trough %DPP-4 inhibition was 18.2% greater than with saxa-5 (p < 0.001), 62.9% greater than with vilda-50-q.d. (p < 0.001), 1.1% greater than with vilda-50-b.i.d. (p = 0.128), and 87.8% greater than with placebo (p < 0.001). Mean %DPP-4 inhibition was nearly maximal at 12 h postdose regardless of active treatment. Thus, these between-group comparisons at trough primarily reflected differences in duration of action. Adverse events reported during the study were transient and mild or moderate in intensity.
Once daily treatment with sitagliptin provided trough DPP-4 inhibition significantly greater than saxagliptin or vildagliptin administered once daily, and similar to that provided by vildagliptin administered twice daily.
Dipeptidyl peptidase-4; Enzyme inhibition; Saxagliptin; Sitagliptin; Type 2 diabetes; Vildagliptin
To evaluate the clinical efficacy of sitagliptin for reducing plasma glucose levels in Korean subjects with type 2 diabetes mellitus during a 14-week treatment period.
Our study design involved the addition of 100 mg sitagliptin once-daily to three ongoing combination therapy regimens and changing from glimepiride and metformin to sitagliptin and metformin.
The addition of sitagliptin 100 mg/day produced a statistically significant reduction in mean HbA1c level (mean HbA1c reduction of 0.99±0.85%, P<0.01). In the group taking a combination of sitagliptin and metformin (n=143, initial mean HbA1c level=7.48%), the reductions in HbA1c, 2-hour postprandial glucose, and fasting glucose levels were 0.72±0.76% (P<0.01), 47±65 mg/dL (P<0.01), and 15±44 mg/dL (P<0.01), respectively. In the group taking a combination of sitagliptin, glimepiride, and metformin (n=125, initial mean HbA1c level=8.42%), the reductions in HbA1c, 2-hour postprandial glucose, and fasting glucose levels were 1.09±0.86% (P<0.01), 62±64 mg/dL (P<0.01), and 31±45 mg/dL (P<0.01), respectively. In the group taking a combination of sitagliptin, glimepiride, metformin, and α-glucosidase inhibitor (n=63, initial mean HbA1c level=9.19%), the reductions in HbA1c, 2-hour postprandial glucose, and fasting glucose levels were 1.27±0.70% (P<0.01), 72±65 mg/dL (P<0.01), and 35±51 mg/dL (P<0.01), respectively. In the group that had previous hypoglycemic events and that changed from glimepiride to sitagliptin, HbA1c level did not change but fasting glucose increased significantly (14±29 mg/dL, P<0.01).
Sitagliptin combination therapy for 14 weeks significantly improved glycemic control and was well-tolerated in Korean subjects with type 2 diabetes mellitus.
Efficacy; Fasting plasma glucose; HbA1c; Sitagliptin; 2-hour postmeal glucose
The dipeptidyl peptidase-4 (DPP-4) inhibitors Sitagliptin and Vildagliptin lower blood glucose by augmenting endogenous levels of glucagon-like peptide-1 (GLP-1), an incretin which also confers cardioprotection. As such, we hypothesized that treatment with DPP-4 inhibitors are also cardioprotective.
In ex vivo experiments: Male Sprague–Dawley rats were randomized to receive by oral gavage either Vildagliptin (20 mg/kg/day), Sitagliptin (100 mg/kg/day), or water for 2 weeks. Excised hearts were Langendorff-perfused with buffer containing either 5 mmol/L or 11 mmol/L glucose and subjected to 35 minutes ischaemia/120 minutes reperfusion. In in vivo experiments: Male young Wistar and Sprague–Dawley rats, middle aged Wistar and Goto-Kakizaki diabetic rats were randomized to receive by oral gavage either Sitagliptin (100 mg/kg/day), or water for 2 weeks. Rats were then subjected to 30 minutes ischaemia/120 minutes reperfusion and infarct size ascertained.
Two weeks pre-treatment with either Vildagliptin or Sitagliptin reduced ex vivo myocardial infarction (MI) size in hearts perfused with buffer containing 11 mmol/L glucose but not 5 mmol/L glucose. This effect was abolished by Exendin 9–39 (GLP-1 receptor antagonist) and H-89 (PKA antagonist). Treatment of perfused hearts with native GLP-1 was also glucose-sensitive, reducing MI size, at glucose concentrations 7, 9, and 11 mmol/L but not at 5 mmol/L. Finally, Sitagliptin reduced in vivo MI size in middle aged Wistar (7-8 mmol/L glucose) and Goto-Kakizaki (9-10 mmol/L glucose) rats where blood glucose was elevated, but not in young Wistar (5 mmol/L glucose) or Sprague–Dawley (5 mmol/L glucose) rats, where blood glucose was normal.
We find that chronic treatment with DPP-4 inhibitors reduced MI size, via the GLP-1 receptor-PKA pathway, in a glucose-dependent manner. Glucose-sensitive cardioprotection of endogenous GLP-1 in diabetic patients may in part explain why intensive control of serum glucose levels has been associated with increased cardiovascular risk.
Ischaemia; Reperfusion; Glucagon-like peptide 1; Sitagliptin; Vildagliptin; Dipeptidyl peptidase-4 inhibitor; Blood glucose
Aim: To confirm the efficacy of vildagliptin in patients with type 2 diabetes (T2D) by testing the hypothesis that glycosylated haemoglobin (HbA1c) reduction with vildagliptin is superior to that with voglibose after 12 weeks of treatment.
Methods: In this 12-week, randomized, double-blind, active-controlled, parallel-group study, the efficacy and safety of vildagliptin (50 mg bid, n = 188) was compared with that of voglibose (0.2 mg tid, n = 192) in patients with T2D who were inadequately controlled with diet and exercise.
Results: The characteristics of two groups were well matched at baseline. The mean age, body mass index (BMI) and HbA1c were 59.1 years, 24.9 kg/m2 and 7.6%, respectively. At baseline, fasting plasma glucose (FPG) and 2-h postprandial glucose (PPG) were 9.01 mmol/l (162.2 mg/dl) and 13.57 mmol/l (244.3 mg/dl), respectively. The adjusted mean change in HbA1c from baseline to endpoint was −0.95 ± 0.04% in the vildagliptin-treated patients and −0.38 ± 0.04% in those receiving voglibose (between-group change = 0.57 ± 0.06%, 95% confidence interval (CI) (−0.68 to −0.46%), p < 0.001), showing that vildagliptin was superior to voglibose. Endpoint HbA1c ≤ 6.5% was achieved in 51% vildagliptin-treated patients compared with 24% patients who were on voglibose (p < 0.001). Vildagliptin also exhibited significantly (p < 0.001) greater reduction compared with voglibose in both FPG [1.34 vs. 0.43 mmol/l (24.1 vs. 7.8 mg/dl)] and 2-h PPG [2.86 vs. 1.1 mmol/l (51.5 vs. 19.8 mg/dl)]. Overall adverse events (AEs) were lower in the vildagliptin-treated patients compared with that in the voglibose-treated patients (61.2 vs. 71.4%), with no incidence of hypoglycaemia and serious adverse events with vildagliptin. Gastrointestinal AEs were significantly lower with vildagliptin compared with that of the voglibose (18.6 vs. 32.8%; p = 0.002).
Conclusions: Vildagliptin (50 mg bid) showed superior efficacy and better tolerability compared with voglibose in Japanese patients with T2D.
DPP-4 inhibitor; HbA1c; type 2 diabetes mellitus; vildagliptin; voglibose
Sitagliptin is one of the dipeptidyl peptidase-4 (DPP-4) inhibitors which prevent the inactivation of incretins, increasing the endogenous active incretin levels. Incretins stimulate insulin secretion from pancreatic β-cells and inhibit glucagon secretion from pancreatic α-cells, which is favorable for the treatment of diabetes. Sitagliptin is released on December, 2009, in Japan. We retrospectively studied effects of 6-month-treatment with sitagliptin on glucose and lipid metabolism, blood pressure, body weight and renal function in patients with type 2 diabetes by a chart-based analysis.
We retrospectively studied 220 type 2 diabetic patients who have taken sitagliptin for 6 months by a chart-based analysis. Subjects studied include patients treated with sitagliptin monotherapy, sitagliptin add-on therapy, and switching from glinide to sitagliptin. We selected patients who have both data before and after 6-month sitagliptin treatment and compared the data before the sitagliptin treatment with the data at 6 month after the sitagliptin treatment started. Body weight, blood pressure, plasma glucose, hemoglobin A1c (HbA1c), serum lipids, and estimated glomerular filtration rate in type 2 diabetic patients were measured almost at the same time points before and after 6-month-treatment with sitagliptin.
Body weight was significantly reduced after 6-month sitagliptin treatment by 0.8 kg. HbA1c levels were also significantly decreased after the sitagliptin treatment by 0.6%. We found a significant and negative correlation between change in body weight and body mass index at baseline. We also observed a significant and negative correlation between change in HbA1c and HbA1c levels at baseline. The number of patients who showed the absence of urinary glucose was significantly increased after the sitagliptin treatment.
Body weight; Chart-based analysis; Hemoglobin A1c; Sitagliptin; Urinary glucose
Although incretin therapy is clinically available in patients with type 2 diabetes undergoing hemodialysis, no study has yet examined whether incretin therapy is capable of maintaining glycemic control in this group of patients when switched from insulin therapy. In this study, we examined the efficacy of incretin therapy in patients with insulin-treated type 2 diabetes undergoing hemodialysis.
Ten type 2 diabetic patients undergoing hemodialysis received daily 0.3 mg liraglutide, 50 mg vildagliptin, and 6.25 mg alogliptin switched from insulin therapy on both the day of hemodialysis and the non-hemodialysis day. Blood glucose level was monitored by continuous glucose monitoring. After blood glucose control by insulin, patients were treated with three types of incretin therapy in a randomized crossover manner, with continuous glucose monitoring performed for each treatment.
During treatment with incretin therapies, severe hyperglycemia and ketosis were not observed in any patients. Maximum blood glucose and mean blood glucose on the day of hemodialysis were significantly lower after treatment with liraglutide compared with treatment with alogliptin (p < 0.05), but not with vildagliptin. The standard deviation value, a marker of glucose fluctuation, on the non-hemodialysis day was significantly lower after treatment with liraglutide compared with treatment with insulin and alogliptin (p < 0.05), but not with vildagliptin. Furthermore, the duration of hyperglycemia was significantly shorter after treatment with liraglutide on both the hemodialysis and non-hemodialysis days compared with treatment with alogliptin (p < 0.05), but not with vildagliptin.
The data presented here suggest that patients with type 2 diabetes undergoing hemodialysis and insulin therapy could be treated with incretin therapy in some cases.
Type 2 diabetes; Hemodialysis; Incretin therapy; CGM; Insulin therapy
The present study investigated the efficacy and safety of vildagliptin-metformin treatment compared to those of glimepiride-metformin treatment for type 2 diabetes.
In a randomized, open-label, comparative study, 106 patients with type 2 diabetes were enrolled. The primary endpoint was a reduction in HbA1c from baseline and secondary endpoints included fasting plasma glucose (FPG) or 2-hour postprandial glucose (2h-PPG) reduction from baseline, as well as HbA1c responder rate and HbA1c reduction according to baseline HbA1c category.
Comparable HbA1c reduction was observed with a mean±standard deviation change from baseline to the 32-week endpoint of -0.94±1.15% in the vildagliptin group and -1.00±1.32% in the glimepiride group. A similar reduction in 2h-PPG (vildagliptin group 3.53±4.11 mmol/L vs. the glimepiride group 3.72±4.17 mmol/L) was demonstrated, and the decrements in FPG (vildagliptin group 1.54±2.41 mmol/L vs. glimepiride group 2.16±2.51 mmol/L) were not different between groups. The proportion of patients who achieved an HbA1c less than 7% at week 32 was 50.1% in the vildagliptin group and 56.0% in the glimepiride group. An average body weight gain of 2.53±1.21 kg in the glimepiride group was observed in contrast with the 0.23±0.69 kg weight gain noted in the vildagliptin group. A 10-fold lower incidence of hypoglycemia was demonstrated in the vildagliptin group, in addition to an absence of severe hypoglycemia.
Vildagliptin-metformin treatment provided blood glucose control efficacy comparable to that of glimepiride-metformin treatment and resulted in better adverse event profiles with lower risks of hypoglycemia and weight gain.
Diabetes mellitus, type 2; Glimepiride; Metformin; Vildagliptin
The objective of this study was to evaluate the efficacy and safety of vildagliptin, a potent dipeptidyl peptidase-4 inhibitor, as an add-on to metformin in Japanese patients with type 2 diabetes mellitus (T2DM).
This multicenter, 12-week, randomized, double-blind, placebo-controlled, parallel-arm study compared vildagliptin 50 mg bid with placebo in T2DM patients who were inadequately controlled [glycosylated hemoglobin (HbA1c) 7.0–10.0%] on a stable daily dose of metformin monotherapy (250 mg bid or 500 mg bid).
A total of 139 patients were randomized to receive either vildagliptin (n = 69) or placebo (n = 70). Patient demographics were comparable between the groups at baseline. After 12 weeks of treatment, adjusted mean change in HbA1c was −1.1% in the vildagliptin group (baseline 8.0%) and −0.1% in the placebo group (baseline 8.0%), with a between-treatment difference of −1.0% (P < 0.001). Vildagliptin showed a similar reduction in HbA1c of −1.1% for both the subpopulations of patients receiving metformin 250 mg bid or 500 mg bid (P < 0.001 vs. baseline). Significantly more patients in the vildagliptin group achieved an HbA1c target of ≤6.5% (30.9%) and <7.0% (64.1%) compared with the placebo group (P < 0.001). The between-treatment difference in adjusted mean change in fasting plasma glucose was −1.6 mmol/L (P < 0.001) in favor of vildagliptin. Patients in the vildagliptin and placebo groups reported comparable incidences of adverse events (44.1% vs. 41.4%). No deaths or hypoglycemic events were reported in the study.
Vildagliptin 50 mg bid added to metformin improved glycemic control without any tolerability issues and hypoglycemia in Japanese patients with T2DM inadequately controlled on metformin monotherapy.
Electronic supplementary material
The online version of this article (doi:10.1007/s13300-014-0059-x) contains supplementary material, which is available to authorized users.
Antidiabetic drug; Dipeptidyl peptidase-4 inhibitor; Glycemic control; Metformin; Randomized trial; Type 2 diabetes mellitus; Vildagliptin
To examine the efficacy of sitagliptin and miglitol when added to ongoing insulin treatment in a patient with type 2 diabetes who had undergone partial gastrectomy.
Continuous glucose monitoring (CGM) was performed and either sitagliptin or miglitol, or both, were added to fixed-dose insulin therapy. Blood was drawn at 0, 30, 60, and 120 min after breakfast, and C-peptide, glucagon, glucagon-like peptide (GLP)-1, and glucose-dependent insulinotropic peptide (GIP) were measured.
CGM showed that compared to insulin alone, the addition of either sitagliptin or miglitol, or both, to insulin achieved better glucose control. Compared to insulin alone, early postprandial increments in plasma C-peptide levels and suppressed glucagon levels were observed when sitagliptin was added. Glucagon suppression was even more prominent when both sitagliptin and miglitol were added. Compared to insulin alone, GLP-1 levels were higher during the early postprandial stage when sitagliptin or miglitol was added and even higher when both were added. GIP levels decreased when sitagliptin or miglitol, or both, were added to insulin therapy.
The authors showed that the addition of sitagliptin or miglitol, or both, was effective in this insulin-treated patient with diabetes who had undergone gastrectomy.
C-peptide; Continuous glucose monitoring; Glucagon-like peptide 1; Glucose-dependent insulinotropic peptide; Insulin; Miglitol; Sitagliptin; Type 2 diabetes
AIM: To investigate efficacy and safety of vildagliptin compared to other oral antidiabetics in clinical practice in Germany.
METHODS: In this prospective, open, observational study, patients with type 2 diabetes mellitus (T2DM) previously on oral monotherapy were selected by their treating physician to receive either vildagliptin add-on to metformin (cohort 1), vildagliptin + metformin single-pill combination (SPC) (cohort 2) or another dual combination therapy with oral antidiabetic drugs (OADs) (cohort 3). According to routine clinical practice, interim examinations occurred every 3 mo: at baseline, after approximately 3 mo and after approximately 6 mo. Parameters documented in the study included demographic and diagnostic data, history of T2DM, data on diabetes control, vital signs, relevant prior and concomitant medication and disease history. Efficacy was assessed by changes in HbA1c and fasting plasma glucose (FPG) 3 mo and 6 mo after initiation of dual combination therapy. Safety was assessed by adverse event reporting and measurement of specific laboratory values (serum creatinine, total bilirubin, alanine aminotransferase, aspartate aminotransferase, creatine kinase).
RESULTS: Between October 2009 and January 2011, a total of 3881 patients were enrolled in this study. Since 47 patients were withdrawn due to protocol violations, 3834 patients were included in the statistical analysis. There were no relevant differences between the three cohorts concerning age, body weight and body mass index. Average diabetes duration was approximately 6 years and mean HbA1c was between 7.6% and 7.9% at baseline. Antidiabetic treatment was recorded in 3648 patients. Patients were treated with vildagliptin add-on to metformin (n = 603), vildagliptin + metformin (SPC) (n = 2198), and other oral OADs including combinations of metformin with sulfonylurea (n = 370), with glitazones (n = 123), other dipeptidyl peptidase-4 inhibitors (n = 99). After 6 mo of treatment, the absolute decrease in HbA1c (mean ± SE) was significantly more pronounced in patients receiving vildagliptin add-on to metformin (-0.9% ± 0.04%) and vildagliptin + metformin (SPC) (-0.9% ± 0.03%) than in patients receiving other OADs (-0.6% ± 0.04%; P < 0.0001). In addition, significant cohort differences were observed for the improvement in FPG after 6 mo treatment (vildagliptin add-on to metformin: -291 mg/L ± 18.3 mg/L; vildagliptin +metformin (SPC): -305 mg/L ± 9.6 mg/L; other antidiabetic drugs: -209 mg/L ± 14.0 mg/L for (P < 0.0001). Moderate decreases in body weight (absolute difference between last control and baseline: mean ± SE) were observed for patients in all cohorts (vildagliptin add-on to metformin: -1.4 kg ± 0.17 kg; vildagliptin + metformin (SPC): -1.7 kg ± 0.09 kg; other OADs: -0.8 kg ± 0.13 kg). No significant differences in adverse events (AEs) and other safety measures were observed between the cohorts. When performing an additional analysis by age (patients < 65 years vs patients ≥ 65 years), there was no relevant difference in the most common AEs between the two age groups and the AE profile was similar to that of the overall patient population.
CONCLUSION: Clinical practice confirms that vildagliptin is an effective and well-tolerated treatment in combination with metformin in T2DM patients.
Observational study; Combination therapy; Vildagliptin; Metformin; Type 2 diabetes
Glucose fluctuations including robust postprandial hyperglycemia are a risk for promoting atherosclerosis and diabetic complications. The α-glucosidase inhibitors and the dipeptidyl peptidase-4 (DPP-4) inhibitors have been found to effectively decrease postprandial hyperglycemia independently. Therefore, glycemic control with the combination of these drugs is warranted.
Continuous glucose monitoring (CGM) was performed for 3 patients with type 2 diabetes and 1 control subject from the beginning to the end of the study. Medications were not administered to any of the subjects on the first day of the study. From the second day to the end of study (days 2-5), the subjects received miglitol (150 mg per day) and on days 4 and 5, sitagliptin (50 mg per day) was added to the treatment regimen. On the first, third, and fifth days of the study, blood was drawn at 0, 30, 60, 120, 180, and 240 min after breakfast for measurements of serum insulin, 1,5-anhydroglucitol (1,5-AG), plasma glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic peptide (GIP).
Measurements of CGM and 1,5-AG levels showed that miglitol attenuated the escalation and fluctuation of glucose levels, and this was even more pronounced with the combination of miglitol and sitagliptin. The patterns of insulin secretion and glucagon secretion with miglitol alone or with a combination of miglitol and sitagliptin were various in the study subjects. Miglitol alone enhanced the release of GLP-1 in 1 patient with type 2 diabetes and the control subject, whereas the combination of miglitol and sitagliptin increased GLP-1 levels to varying degrees in all the subjects. Except for 1 subject, none of the subjects showed any change in GIP levels after the addition of sitagliptin, compared to the administration of miglitol alone.
In conclusion, CGM measurements revealed that a combination of the α-GI miglitol and the DPP-4 inhibitor sitagliptin effectively reduced postprandial glucose fluctuation and stabilized blood glucose levels. Completely different response patterns of insulin, glucagon, GLP-1, and GIP were observed among the study subjects with either medication alone or in combination, suggesting that individual hormone-dependent glycemic responses to the α-GI and DPP-4 inhibitors are complicated and multifactorial.
miglitol; sitagliptin; glucagon-like peptide-1 (GLP-1); glucose-dependent insulinotropic peptide (GIP); continuous glucose monitoring (CGM)
The aim of the present study was to determine the effect of sitagliptin on microalbuminuria in patients with type 2 diabetes mellitus.
Materials and Methods
A total of 85 patients with type 2 diabetes mellitus (age >20 years, <80 years, hemoglobin A1c [HbA1c] <8.4%) were randomized to patients taking sitagliptin 50 mg or other oral glucose‐lowering agents. The following parameters were evaluated at 0, 3 and 6 months after the treatment: bodyweight, blood pressure, HbA1c, fasting plasma glucose, fasting plasma insulin, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol, triglycerides, estimated glomerular filtration rate and urinary albumin excretion. The primary outcome was changes in urinary albumin excretion at 6 months.
Significant and comparable falls in HbA1c and fasting plasma glucose were found in both groups. However, sitagliptin significantly reduced urinary albumin excretion within 6 months, especially in patients with high urinary albumin at baseline. A total of 27 patients with normoalbuminuria showed a reduction in urinary albumin excretion, suggesting that sitagliptin prevents the development of albuminuria. A total of 15 patients with albuminuria showed a reduction in urinary albumin excretion, suggesting the beneficial effect of sitagliptin in the early stage of diabetic nephropathy. There was a significant correlation between improvement of proteinuria and that of diastolic blood pressure.
The results suggested that sitagliptin improved albuminuria, in addition to improving glucose. The mechanism of the reduction of albuminuria by sitagliptin could be a direct effect, as well as an increase in active glucagon‐like peptide‐1, independently affecting blood pressure, bodyweight and glucose metabolism. This trial was registered with the University Hospital Medical Information Network (UMIN no. #000010871).
Albuminuria; Dipeptidyl peptidase‐4 inhibitor; Sitagliptin
(J Diabetes Invest, doi: 10.1111/j.2040‐1124.2012.00221.x, 2012)
Aims/Introduction: To determine the efficacy and safety of sitagliptin monotherapy and combination therapy in Japanese type 2 diabetes patients after 3 months’ therapy.
Materials and Methods: A retrospective, observational study of 741 type 2 diabetes patients was carried out; 110 received sitagliptin monotherapy, and 631 received combination therapy with sitagliptin when other oral medications were insufficient. The primary outcome measure was glycated hemoglobin (HbA1c) measured at 0, 4 and 12 weeks of sitagliptin therapy.
Results: In the monotherapy and combination therapy groups, HbA1c decreased significantly after 12 weeks. Target HbA1c (<7%) was achieved in 39.1% overall. On logistic regression analysis, baseline HbA1c was the strongest contributing factor for achieving target HbA1c; baseline body mass index and duration of diabetes were also significant factors. A total of 82 patients (11%) were unresponsive to sitagliptin. These patients’ baseline body mass index was significantly higher and their baseline HbA1c was significantly lower than those of patients who responded to sitagliptin. The most commonly co‐administered drugs were sulfonylureas (508 patients). In these patients, the dose of sulfonylurea decreased with time. In 66 patients whose sulfonylurea dosage was reduced when sitagliptin was started, HbA1c and bodyweight decreased significantly after 12 weeks. A total of 24 patients receiving sulfonylureas had mild hypoglycemia, but none discontinued sitagliptin.
Conclusions: Sitagliptin was effective and safe as both monotherapy and combination therapy in Japanese type 2 diabetes patients. When sulfonylureas were ineffective, sitagliptin improved glycemic control. In patients whose sulfonylurea dose was reduced at the start of sitagliptin, blood glucose improved and bodyweight decreased after 12 weeks.
Diabetes mellitus; Sitagliptin; Sulfonylurea
Type 2 Diabetes mellitus (T2DM) is a common comorbidity in patients after heart transplantation (HTx) and is associated with adverse long-term outcomes.
The retrospective study reported here analyzed the effects of vildagliptin therapy in stable patients post-HTx with T2DM and compared these with control patients for matched-pairs analysis. A total of 30 stable patients post-HTx with T2DM were included in the study. Fifteen patients (mean age 58.6 ± 6.0 years, mean time post-HTx 4.9 ± 5.3 years, twelve male and three female) were included in the vildagliptin group (VG) and 15 patients were included in the control group (CG) (mean age 61.2 ± 8.3 years, mean time post-HTx 7.2 ± 6.6 years, all male).
Mean glycated hemoglobin (HbA1c) in the VG was 7.4% ± 0.7% before versus 6.8% ± 0.8% after 8 months of vildagliptin therapy (P = 0.002 vs baseline). In the CG, HbA1c was 7.0% ± 0.7% versus 7.3% ± 1.2% at follow-up (P = 0.21). Additionally, there was a significant reduction in mean blood glucose in the VG, from 165.0 ± 18.8 mg/dL to 147.9 ± 22.7 mg/dL (P = 0.002 vs baseline), whereas mean blood glucose increased slightly in the CG from 154.7 ± 19.7 mg/dL to 162.6 ± 35.0 mg/dL (P = 0.21). No statistically significant changes in body weight (from 83.3 ± 10.8 kg to 82.0 ± 10.9 kg, P = 0.20), total cholesterol (1.5%, P = 0.68), or triglyceride levels (8.0%, P = 0.65) were seen in the VG. No significant changes in immunosuppressive drug levels or dosages were observed in either group.
Vildagliptin therapy significantly reduced HbA1c and mean blood glucose levels in post-HTx patients in this study with T2DM and did not have any negative effects on lipid profile or body weight. Thus, vildagliptin therapy presented an interesting therapeutic approach for this selected patient cohort.
immunosuppression; glycated hemoglobin; mean blood glucose
The aim of this study was to assess the efficacy of a combination therapy of vildagliptin plus an α-glucosidase inhibitor for patients with type II diabetes mellitus. Type II diabetic patients exhibiting poor glycemic control following α-glucosidase inhibitor treatment for at least two months were selected and randomly distributed into vildagliptin and placebo groups. The body weight, fasting blood glucose (FBG), postprandial glucose (PPG), glycated hemoglobin (HBA1c) and blood lipid levels and hepatorenal functions of the patients were determined before and 12 weeks after the trial. Following the trial, the FBG, PPG, HbA1c, cholesterol (CHOL) and triglyceride (TG) levels in the vildagliptin group were significantly decreased compared with the pretreatment levels (P<0.05), whereas only the PPG level in the placebo group decreased (P<0.05). The FBG, PPG and HbA1c levels in the vildagliptin group were markedly lower than those in the placebo group 12 weeks after the trial. A comparison of the body weights and hepatorenal functions before and after the trial or between groups did not show statistically significant differences. The combination therapy of vildagliptin plus an α-glucosidase inhibitor effectively reduced the FBG, PPG and HbA1c levels in patients without inducing weight gain or hepatorenal dysfunction. However, the therapy may have caused a reduction in the blood lipid levels.
type II diabetes mellitus; vildagliptin; α-glucosidase inhibitor; body weight; blood lipid; hepatorenal function
The aim of the present study was to assess the efficacy and safety of vildagliptin plus metformin combination therapy in patients with type II diabetes mellitus. Type II diabetic patients with poor glycemic control following at least three months of metformin treatment were selected and randomized into two groups. Vildagliptin or placebo was administered with metformin. Body weight, fasting blood glucose (FBG), postprandial glucose (PPG), glycated hemoglobin (HbA1c), blood lipid and hepatorenal function levels were analyzed in the patients prior to and 24-weeks after the trial. FBG, PPG and HbA1c levels of the patients in the vildagliptin group significantly decreased following the trial, whereas no statistically significant differences were observed in the various indicators of the placebo group prior to and following the trial. The FBG, PPG and HbA1c levels in the vildagliptin group were significantly lower compared with the placebo group 24-weeks after the trial. Comparisons of body weight, blood lipid and hepatorenal function between the groups prior to and following the trial exhibited no statistically significant differences. Therefore, vildagliptin plus metformin combination therapy effectively reduced FBG, PPG and HbA1c levels in patients with no risk of weight gain or hepatorenal dysfunction.
type II diabetes mellitus; vildagliptin; metformin; body weight; blood lipid; hepatorenal function
Traditional blood glucose lowering agents do not prevent the progressive loss of beta cell function in patients with type 2 diabetes. The dipeptidylpeptidase (DPP)-4 inhibitor vildagliptin improves beta cell function both acutely and chronically (up to 2 years). Whether this effect persists after cessation of treatment remains unknown. Here, we assessed the insulin secretory capacity in drug-naive patients with type 2 diabetes after a 52 week treatment period with vildagliptin or placebo, and again after a 12 week washout period.
This study was conducted at a single university medical centre, and was a double-blind, randomised clinical trial in 59 drug-naive patients with type 2 diabetes and mild hyperglycaemia to either vildagliptin 100 mg (n = 29) or placebo (n = 30). Randomisation was performed by a validated 1:1 system. Neither patient, nor caregiver, was informed about the assigned treatment. Inclusion criteria were drug-naive patients ≥30 years, with HbA1c ≤7.5% and BMI of 22–45 kg/m2. The mildly hyperglycaemic patient population was chosen to minimise glucose toxicity as a confounding variable. Beta-cell function was measured during an arginine-stimulated hyperglycaemic clamp at week 0, week 52 and after a 12 week washout period. All patients with at least one post-randomisation measure were analysed (intent-to-treat).
Fifty-two week vildagliptin 100 mg (n = 26) treatment increased the primary efficacy variable, combined hyperglycaemia and arginine-stimulated C-peptide secretion (AIRarg), by 5.0 ± 1.8 nmol/l × min, while it decreased by 0.8 ± 1.8 nmol/l × min with placebo (n = 25) (between-group difference p = 0.030). No significant between-group difference in AIRarg was seen after the 12 week washout period. The between-group difference adjusted mean 52 week changes from baseline was −0.19 ± 0.11, p = 0.098 and −0.22 ± 0.23%, p = 0.343 for HbA1c and fasting plasma glucose, respectively. There were no suspected drug treatment-related serious adverse events.
One year treatment with vildagliptin significantly increased beta cell secretory capacity. This effect was not maintained after the washout, indicating that this increased capacity was not a disease modifying effect on beta cell mass and/or function.
This study was sponsored by the Novartis Pharmaceutical Cooperation.
Beta cell function; Hyperglycaemic clamp; Randomised clinical trial; Type 2 diabetes; Vildagliptin
The broadly used combination of metformin and sulphonylurea (SU) often fails to bring patients to glycaemic goal. This study assessed the efficacy and safety of vildagliptin as add-on therapy to metformin plus glimepiride combination in patients with type 2 diabetes mellitus (T2DM) who had inadequate glycaemic control.
A multicentre, double-blind, placebo-controlled study randomized patients to receive treatment with vildagliptin 50 mg bid (n = 158) or placebo (n = 160) for 24 weeks.
After 24 weeks, the adjusted mean change in haemoglobin A1c (HbA1c) was −1.01% with vildagliptin (baseline 8.75%) and −0.25% with placebo (baseline 8.80%), with a between-treatment difference of −0.76% (p < 0.001). Significantly more patients on vildagliptin achieved the HbA1c target <7% (28.3% vs. 5.6%; p < 0.001). The difference in fasting plasma glucose reduction between vildagliptin and placebo was −1.13 mmol/l (p < 0.001). In subgroup of patients with baseline HbA1c ≤8%, vildagliptin reduced HbA1c by 0.74% from baseline 7.82% (between-treatment difference: –0.97%; p < 0.001) with significantly more patients achieving the HbA1c target <7% (38.6% vs. 13.9%; p = 0.014). Vildagliptin was well tolerated with low incidence of hypoglycaemia, slightly higher than with placebo (5.1% vs. 1.9%) and no clinically relevant weight gain.
Vildagliptin significantly improved glycaemic control in patients with T2DM inadequately controlled with metformin plus glimepiride combination. The addition of vildagliptin was well tolerated with low risk of hypoglycaemia and weight gain. This makes vildagliptin an attractive treatment option for patients failing on metformin plus SU particularly in patients with baseline HbA1c ≤8%.
DPP-4 inhibitor; glimepiride; metformin; oral antidiabetic drug; type 2 diabetes; vildagliptin
Sitagliptin is a highly selective dipeptidyl peptide-4 (DPP-4) inhibitor that increases blood levels of active glucagon-like peptide (GLP)-1 and glucose-dependent insulinotrophic polypeptide (GIP), resulting in increased insulin secretion. While studies conducted in other countries have indicated the efficacy and safety of using sitagliptin to treat type 2 diabetes mellitus (T2DM), its predictors of effects to sitagliptin are not well understood. Therefore, we evaluated the predictive clinical parameters for the therapeutic benefits of sitagliptin when added to an ongoing metformin or sulfonylurea therapy in Korean T2DM subjects.
We obtained data from 251 Korean T2DM subjects who had recently started taking sitagliptin as add-on therapy. Exclusion criteria included any insulin use. Changes in HbA1c (ΔHbA1c) and fasting plasma glucose (ΔFPG) were assessed by comparing baseline levels prior to sitagliptin administration to levels 12 and 24 weeks after treatment. Responders were defined as subjects who experienced decrease from baseline of >10% in ΔHbA1c or >20% in ΔFPG levels at 24 weeks.
We classified 81% of the subjects (204 out of 251) as responders. The responder group had a lower mean body mass index (23.70±2.40 vs. 26.00±2.26, P≤0.01) and were younger (58.83±11.57 years vs. 62.87±12.09 years, P=0.03) than the non-responder group.
In Korean T2DM subjects, sitagliptin responders had lower body mass index and were younger compared to non-responders.
Diabetes mellitus, type 2; Dipeptidyl peptide-4 inhibitor; Sitagliptin
The efficacy and safety of sitagliptin, a highly selective dipeptidyl peptidase‐4 inhibitor, when added to metformin monotherapy was examined in Japanese patients with type 2 diabetes.
Materials and Methods
In this 52‐week, add‐on to metformin study, 149 patients were randomly assigned to receive sitagliptin 50 mg or placebo once daily in a double‐blind fashion for 12 weeks. Thereafter, all patients who completed the double‐blind period of the study received open‐label sitagliptin 50 mg once daily for 40 weeks, with the investigator option of increasing sitagliptin to 100 mg once daily for patients who met predefined glycemic thresholds.
After 12 weeks of treatment, the mean change from baseline in glycated hemoglobin (HbA1c) significantly decreased with sitagliptin relative to placebo (between‐group difference [95% confidence interval] = −0.7% [−0.9 to −0.5] P < 0.001). At week 12, the mean changes in 2‐h post‐meal glucose (−2.6 mmol/L [−3.5 to −1.7]) and fasting plasma glucose (−1.0 mmol/L [−1.3 to −0.6]) also decreased significantly with sitagliptin relative to placebo (P < 0.001 for both). Significant improvements from baseline in glycemic control were also observed in the open‐label period through to week 52. There were no differences between treatment groups in the incidence of adverse events (AEs), including hypoglycemia and predefined gastrointestinal AEs (nausea, vomiting and diarrhea) during the double‐blind period, with similar findings in the open‐label period.
Over a period of 52 weeks, the addition of sitagliptin once‐daily to ongoing metformin therapy was efficacious and generally well tolerated in Japanese patients with type 2 diabetes. This trial was registered with ClinicalTrials.gov (no. NCT00363948).
Metformin; Sitagliptin; Type 2 diabetes