A randomized placebo-controlled trial of repaglinide in the treatment of type 2 diabetes. Nateglinide alone and in combination with metformin improves glycemic control by reducing mealtime glucose levels in type 2 diabetes. The effect of prandial glucose regulation with repaglinide on treatment satisfaction, wellbeing and health status in patients with pharmacotherapy naïve Type 2 diabetes: a placebo-controlled, multicentre study. Repaglinide improves blood glucose control in sulphonylurea-naive type 2 diabetes. Rapid and short-acting mealtime insulin secretion with nateglinide controls both prandial and mean glycemia. Repaglinide versus nateglinide monotherapy: a randomized, multicenter study. Effects of nateglinide on myocardial microvascular reactivity in Type 2 diabetes mellitus--a randomized study using positron emission tomography. Comparison of glycaemic control and cardiovascular risk profile in patients with type 2 diabetes during treatment with either repaglinide or metformin. Effect of repaglinide addition to metformin monotherapy on glycemic control in patients with type 2 diabetes. Repaglinide versus metformin in combination with bedtime NPH insulin in patients with type 2 diabetes established on insulin/metformin combination therapy. Efficacy and safety of combination therapy: repaglinide plus metformin versus nateglinide plus metformin. Repaglinide in type 2 diabetes: a 24-week, fixed-dose efficacy and safety study. Efficacy and safety of nateglinide in type 2 diabetic patients with modest fasting hyperglycemia.
The objective of the study was to assess the efficacy and safety of repaglinide compared with placebo in the treatment of patients with type 2 diabetes.
                This was a phase II multicenter, double-blind, placebo-controlled, randomized, dose-adjustment and maintenance trial. After screening and a 2-week washout period, 99 patients were randomized to receive either repaglinide (n = 66) or placebo (n = 33). Patients underwent 6 weeks of dose adjustment followed by 12 weeks of dose maintenance. Fasting and stimulated glycosylated hemoglobin (HbA1c), plasma glucose, insulin, and C-peptide were measured at predetermined intervals. Adverse events and hypoglycemic episodes were recorded.
                From baseline to last visit, mean HbA1c decreased from 8.5 to 7.8% in patients treated with repaglinide and increased from 8.1 to 9.3% in patients receiving placebo, with a statistically significant difference of - 1.7% (P < 0.0001) between treatment groups at the last visit. Mean fasting plasma glucose and postprandial glucose increased in patients receiving placebo and decreased in patients treated with repaglinide, with statistically significant (P < 0.01) differences between groups at the last visit. Concentrations of fasting and postprandial insulin and C-peptide were lower at the last visit compared with baseline for patients treated with placebo and higher for patients treated with repaglinide, and the differences between groups were statistically significant (P < 0.05). Overall, repaglinide was well tolerated.
                This study demonstrated that repaglinide was safe and efficacious in lowering blood glucose concentrations. In addition to overall improvement in glycemic control noted with repaglinide in both sulfonylurea-treated patients and oral hypoglycemic agent-naive patients, repaglinide had a potent glucose-lowering effect in the postprandial period. To evaluate the efficacy and tolerability of nateglinide and metformin alone and in combination in type 2 diabetic patients inadequately controlled by diet, focusing on changes in HbA1c, fasting plasma glucose (FPG), and mealtime glucose excursions.
                In this randomized double-blind study, patients with an HbA1c level between 6.8 and 11.0% during a 4-week placebo run-in received 24 weeks' treatment with 120 mg nateglinide before meals (n = 179), 500 mg metformin three times a day (n = 178), combination therapy (n = 172), or placebo (n = 172). HbA1c and FPG were evaluated regularly, and plasma glucose levels were determined after Sustacal challenge at weeks 0, 12, and 24. Hypoglycemia and other adverse events were recorded.
                At study end point, HbA1c was reduced from baseline with nateglinide and metformin but was increased with placebo (-0.5, -0.8, and +0.5%, respectively; P < or = 0.0001). Changes in FPG followed the same pattern (-0.7, -1.6, and +0.4 mmol/l; P < or = 0.0001). Combination therapy was additive (HbA1c -1.4% and FPG -2.4 mmol/l; P < or = 0.01 vs. monotherapy). After Sustacal challenge, there was a greater reduction in mealtime glucose with nateglinide monotherapy compared with metformin monotherapy or placebo (adjusted area under the curve [AUC]0-130 min -2.1, -1.1, and -0.6 mmol x h(-1) x l(-1); p < or = 0.0001). An even greater effect was observed with combination therapy (AUC0-130 min -2.5 mmol x h(-1) x l(-1); P < or = 0.0001 vs. metformin and placebo). All regimens were well tolerated.
                Nateglinide and metformin monotherapy each improved overall glycemic control but by different mechanisms. Nateglinide decreased mealtime glucose excursions, whereas metformin primarily affected FPG. In combination, nateglinide and metformin had complementary effects, improving HbA1c, FPG, and postprandial hyperglycemia. This prospective, 16-week, randomised, double-blind, parallel-group study assessed the differential impact of the prandial glucose regulating oral hypoglycaemic drug, repaglinide, and placebo upon perceptions of quality of life (QoL) and treatment satisfaction in pharmacotherapy-naive patients with Type 2 diabetes. In addition, the study assessed whether these outcomes were influenced by the patients' level of glycaemic control. A total of 253 patients were randomised in a 2:1 ratio of repaglinide: placebo, with doses taken flexibly with main meals (2-4 per day), whenever they were eaten. Repaglinide was initiated at 0.5 mg per meal, increased to 1 mg after 4 weeks if fasting plasma glucose exceeded 7.8 mmol/l. QoL and treatment satisfaction outcomes were compared using generic and disease-specific self-assessment measures, previously applied in diabetes: the WHO Wellbeing Questionnaire (WHO-WBQ), WHO Diabetes Treatment Satisfaction Questionnaire (WHO-DTSQ) and EuroQoL EQ-5D. Over the trial period, repaglinide-treated patients reported a significant 9% improvement in (WHO-DTSQ) treatment satisfaction score (p < 0.05). No significant increase was associated with placebo. The correlation between decrease in glycated haemoglobin (HbA1c) and increase in treatment satisfaction (WHO-DTSQ) was -0.22 (p < 0.01). Scores obtained with the other measures did not change significantly during the trial in either group, but the cohort exhibited only a slight reduction in wellbeing (WHO-WBQ) and health status (EQ-5D) at baseline compared with the background population. In conclusion, flexible mealtime dosing with oral medication appears to be well accepted by pharmacotherapy-naïve patients with Type 2 diabetes. The results suggest that repaglinide provides a higher level of treatment satisfaction than placebo, and this may in part relate to improved glycaemic control. The prandial glucose regulator repaglinide has a rapid onset of action, a short half-life and is metabolised mainly by the liver. Here we report the findings of a 10-week, double-blind, parallel, placebo controlled, randomised trial with repaglinide in 25 diet-treated, sulphonylurea-naïve patients with Type 2 diabetes. Repaglinide was titrated, based on capillary blood glucose, from 0.5 mg to a maximum of 4 mg, preprandially with breakfast and dinner. After 10 weeks, repaglinide was associated with a decrease in HbA(1c) of 2.3%Hb relative to the placebo group (P=0.018). This reflected a 30% decrease within the repaglinide group from a mean HbA(1c) of 7.0 to 4.9%Hb (P<0.002). Repaglinide was also associated with a decrease in fructosamine, by 0.88 mmol/l, relative to placebo (P<0.001), with a 20% decrease (from 3.80 to 3.04 mmol/l) within the repaglinide group (P<0.001). Fasting and postprandial blood glucose concentrations decreased in association with repaglinide by 3.6 and 6.4 mmol/l, respectively, relative to placebo (P<0.001 in each case). Within the repaglinide group fasting and postprandial blood glucose decreased by 3.9 and 6.2 mmol/l, respectively (P<0.001 in each case). The number of patients reporting hypoglycaemia in the repaglinide group was similar to placebo (15 vs. 20, respectively; NS). Test meal assessments confirmed that repaglinide effectively controls glucose levels by stimulating mealtime insulin secretion. Fasting serum insulin concentration was not raised compared to baseline or placebo during repaglinide therapy, albeit that fasting glucose levels were decreased by repaglinide. Twice-daily meal-related insulin secretagogue therapy with repaglinide, a new short and rapid-acting prandial glucose regulator, is capable of improving all measures of glycaemic control without increased hypoglycaemia or fasting hyperinsulinaemia. The objective of the study was to assess the efficacy and safety of four fixed doses of nateglinide compared with placebo in the treatment of patients with type 2 diabetes with focus on the prandial state.
                This randomized double-blind placebo-controlled multicenter study was conducted in 289 patients who received either nateglinide at doses of 30 mg (n = 51), 60 mg (n = 58), 120 mg (n = 63), or 180 mg (n = 57) or placebo (n = 60) before three main meals for 12 weeks. Levels of HbA1c, fasting plasma glucose (FPG), fructosamine, and plasma lipids were measured at predetermined intervals, and the effects of nateglinide on prandial glucose insulin, C-peptide, and triglyceride levels were measured after a liquid standard meal (Sustacal; Mead Johnson, Evansville, IN). Adverse events and hypoglycemic episodes were recorded.
                After a liquid meal challenge, nateglinide rapidly increased mealtime insulin levels within 30 min of drug intake and reduced mealtime glucose excursions without affecting triglyceride levels. At study end point, reduction of HbA1c levels was statistically significantly greater with nateglinide at doses of 60, 120, and 180 mg than placebo (-0.45, -0.62, and -0.64%, respectively; P<0.05). The mean level of FPG was significantly reduced versus placebo in the nateglinide 120-mg group only (-1.14 mmol/l P<0.01). Overall, nateglinide was well tolerated.
                This study demonstrated that nateglinide improves mealtime and mean glycemic control in a dose-dependent manner by restoring early insulin secretion phase. Nateglinide was well tolerated and is suitable for the treatment of patients with type 2 diabetes. A randomized, parallel-group, open-label, multicenter 16-week clinical trial compared efficacy and safety of repaglinide monotherapy and nateglinide monotherapy in type 2 diabetic patients previously treated with diet and exercise.
                Enrolled patients (n = 150) had received treatment with diet and exercise in the previous 3 months with HbA(1c) >7 and < or =12%. Patients were randomized to receive monotherapy with repaglinide (n = 76) (0.5 mg/meal, maximum dose 4 mg/meal) or nateglinide (n = 74) (60 mg/meal, maximum dose 120 mg/meal) for 16 weeks. Primary and secondary efficacy end points were changes in HbA(1c) and fasting plasma glucose (FPG) values from baseline, respectively. Postprandial glucose, insulin, and glucagon were assessed after a liquid test meal (baseline, week 16). Safety was assessed by incidence of adverse events or hypoglycemia.
                Mean baseline HbA(1c) values were similar in both groups (8.9%). Final HbA(1c) values were lower for repaglinide monotherapy than nateglinide monotherapy (7.3 vs. 7.9%). Mean final reductions of HbA(1c) were significantly greater for repaglinide monotherapy than nateglinide monotherapy (-1.57 vs. -1.04%; P = 0.002). Mean changes in FPG also demonstrated significantly greater efficacy for repaglinide than nateglinide (-57 vs. -18 mg/dl; P < 0.001). HbA(1c) values <7% were achieved by 54% of repaglinide-treated patients versus 42% for nateglinide. Median final doses were 6.0 mg/day for repaglinide and 360 mg/day for nateglinide. There were 7% of subjects treated with repaglinide (five subjects with one episode each) who had minor hypoglycemic episodes (blood glucose <50 mg/dl) versus 0 patients for nateglinide. Mean weight gain at the end of the study was 1.8 kg in the repaglinide group as compared with 0.7 kg for the nateglinide group.
                In patients previously treated with diet and exercise, repaglinide and nateglinide had similar postprandial glycemic effects, but repaglinide monotherapy was significantly more effective than nateglinide monotherapy in reducing HbA(1c) and FPG values after 16 weeks of therapy. To evaluate effects of the oral antidiabetic insulinotropic agent nateglinide on myocardial blood flow (MBF) and microvascular reactivity in Type 2 diabetic patients.
                Forty-seven Type 2 diabetic patients were randomly assigned 2 : 1 to nateglinide 120 mg (t.i.d., n = 33) or placebo (n = 14). At baseline and after 16 weeks of treatment, MBF was quantified using positron emission tomography with N-13 ammonia at rest, during endothelial-dependent stimulation by cold pressor test and during adenosine-mediated vasodilation. Additional blood samples were taken to assess glycaemic control and lipid profile.
                MBF at rest and during adenosine did not change during the study. The percentage of flow increase from rest during cold pressor test did not improve significantly in the nateglinide group vs. placebo (from 26.1 +/- 37.2% to 29.1 +/- 27.8% between week 0 to week 16 for nateglinide vs. 14.9 +/- 37.1% to 18.1 +/- 28.4% for placebo; P = 0.07 for nateglinide when adjusted for higher baseline values). Nateglinide decreased HbA1c by 0.4% (from 7.6 +/- 0.9% to 7.2 +/- 1.3%) compared to an increase of 0.5% in the placebo group (from 7.9 +/- 0.8% to 8.4 +/- 1.7%; P = 0.02 for nateglinide). No differences between the two groups were observed in insulin levels and lipid status.
                Nateglinide neither improved, nor impaired myocardial blood flow in Type 2 diabetic patients. Potential effects on endothelial-dependent myocardial blood flow remain to be investigated further. Positron emission tomography is a sensitive approach to assess the effects of therapeutic agents on myocardial blood flow in patients with diabetes. To compare glycaemic control and cardiovascular risk profile in patients with type 2 diabetes following 12 months' treatment with either repaglinide or metformin.
                This was an open uncontrolled randomised study in n=112 patients with inadequately controlled type 2 diabetes not previously treated with oral hypoglycaemic agents. Patients beginning treatment with either repaglinide or metformin entered an 8-week titration period (to optimise dosage: repaglinide, 2-4 mg/day; metformin, 1500-2500 mg/day) followed by a 12-month treatment period. Glycaemic control and cardiovascular risk factors were determined at baseline and at the end of the treatment period.
                Mean (S.D.) final drug doses were 3 (+/-1) mg/day in the repaglinide group and 2000 (+/-500) mg/day in the metformin group. Significant improvements in glycaemic control [glycated haemoglobin, fasting and 2-h postprandial plasma glucose (PPG)] were demonstrated in both treatment groups. The decrease in PPG was significantly greater in the repaglinide group (P<0.05). During the treatment period, fasting plasma insulin (FPI) decreased significantly in both groups, more so with metformin (P<0.05). Two-hour postprandial plasma insulin (PPI) levels decreased only in the metformin group (P<0.05). Significant improvements between baseline and final visit were demonstrated in one or both groups in the following cardiovascular risk factors: total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglycerides, plasminogen activator inhibitor, lipoprotein(a) and homocysteine. No changes were observed in high-density lipoprotein cholesterol (HDL-C), apolipoprotein A-I, apolipoprotein B, fibrinogen, body mass index (BMI) or blood pressure.
                The use of repaglinide or metformin in drug therapy-nai;ve patients with type 2 diabetes over a 12-month period is associated with improvements in both glycaemic control and cardiovascular risk profile. The latter cannot necessarily be attributed to the pharmacotherapy per se, but provides reassurance in the context of initiating oral hypoglycaemic drug therapy with these agents. To compare the effect of repaglinide in combination with metformin with monotherapy of each drug on glycemic control in patients with type 2 diabetes.
                A total of 83 patients with type 2 diabetes who had inadequate glycemic control (HbA1c > 7.1%) when receiving the antidiabetic agent metformin were enrolled in this multicenter, double-blind trial. Subjects were randomized to continue with their prestudy dose of metformin (n = 27), to continue with their prestudy dose of metformin with the addition of repaglinide (n = 27), or to receive repaglinide alone (n = 29). For patients receiving repaglinide, the optimal dose was determined during a 4- to 8-week titration and continued for a 3-month maintenance period.
                In subjects receiving combined therapy, HbA1c was reduced by 1.4 +/- 0.2%, from 8.3 to 6.9% (P = 0.0016) and fasting plasma glucose by 2.2 mmol/l (P = 0.0003). No significant changes were observed in subjects treated with either repaglinide or metformin monotherapy in HbA1c (0.4 and 0.3% decrease, respectively) or fasting plasma glucose (0.5 mmol/l increase and 0.3 mmol/l decrease respectively). Subjects receiving repaglinide either alone or in combination with metformin, had an increase in fasting levels of insulin between baseline and the end of the trial of 4.04 +/- 1.56 and 4.23 +/- 1.50 mU/l, respectively (P < 0.02). Gastrointestinal adverse events were common in the metformin group. An increase in body weight occurred in the repaglinide and combined therapy groups (2.4 +/- 0.5 and 3.0 +/- 0.5 kg, respectively; P < 0.05).
                Combined metformin and repaglinide therapy resulted in superior glycemic control compared with repaglinide or metformin monotherapy in patients with type 2 diabetes whose glycemia had not been well controlled on metformin alone. Repaglinide monotherapy was as effective as metformin monotherapy. To compare the effect on glycemic control and weight gain of repaglinide versus metformin combined with bedtime NPH insulin in patients with type 2 diabetes.
                A total of 80 subjects treated with 850 or 1,000 mg t.i.d. metformin combined with bedtime NPH insulin were randomized to 13 weeks of open-label treatment with 4 mg t.i.d. repaglinide (n = 39) or metformin (dose unchanged) (n = 41). Insulin dose was titrated at the clinician's discretion, aiming for a fasting blood glucose (FBG) < or =6.0 mmol/l.
                Baseline age, diabetes duration, insulin requirement, weight, BMI, FBG, and HbA(1c) (Diabetes Control and Complications Trial-aligned assay, normal range 4.6-6.2%) were similar. Glycemic control improved (nonsignificantly) with insulin/metformin by (mean) 0.4%, from 8.4 to 8.1% (P = 0.09) but deteriorated with insulin/repaglinide by (mean) 0.4%, from 8.1 to 8.6% (P = 0.03; P = 0.005 between groups). Weight gain was less with insulin/metformin: 0.9 +/- 0.4 kg (means +/- SE) (P = 0.01) versus 2.7 +/- 0.4 kg (P < 0.0001) (P = 0.002 between groups). The Diabetes Treatment Satisfaction Questionnaire score (potential range 0 [minimum] to 36 [maximum]) increased from 32.4 +/- 0.8 to 34.1 +/- 0.5 (P = 0.01) with insulin/metformin but decreased from 32.5 +/- 0.9 to 29.1 +/- 1.3 (P < 0.002) with insulin/repaglinide.
                Combined with bedtime NPH insulin, metformin provides superior glycemic control to repaglinide with less weight gain and improved diabetes treatment satisfaction. An open-label, parallel-group, randomized, multicenter trial was conducted to compare efficacy and safety of repaglinide versus nateglinide, when used in a combination regimen with metformin for treatment of type 2 diabetes.
                Enrolled patients (n = 192) had HbA(1c) >7% and < or =12% during previous treatment with a sulfonylurea, metformin, or low-dose Glucovance (glyburide < or =2.5 mg, metformin < or =500 mg). After a 4-week metformin run-in therapy period (doses escalated to 1,000 mg b.i.d.), patients were randomized to addition of repaglinide (n = 96) (1 mg/meal, maximum 4 mg/meal) or nateglinide (n = 96) (120 mg/meal, reduced to 60 mg if needed) to the regimen for 16 weeks. Glucose, insulin, and glucagon were assessed after a liquid test meal at baseline and week 16.
                Final HbA(1c) values were lower for repaglinide/metformin treatment than for nateglinide/metformin (7.1 vs. 7.5%). Repaglinide/metformin therapy showed significantly greater mean reductions of HbA(1c) (-1.28 vs. -0.67%; P < 0.001) and of fasting plasma glucose (FPG) (-39 vs. -21 mg/dl; P = 0.002). Self-monitoring of blood glucose profiles were significantly lower for repaglinide/metformin before breakfast, before lunch, and at 2:00 A.M. Changes in the area under the curve of postprandial glucose, insulin, or glucagon peaks after a test meal were not significantly different for the two treatment groups during this study. Median final doses were 5.0 mg/day for repaglinide and 360 mg/day for nateglinide. Safety assessments were comparable for the two regimens.
                The addition of repaglinide to metformin therapy resulted in reductions of HbA(1c) and FPG values that were significantly greater than the reductions observed for addition of nateglinide. In this 24-week multicenter, double-blind, randomized, fixed-dose trial, 361 patients having type 2 diabetes received daily preprandial treatment with placebo (n = 75), repaglinide 1 mg (n = 140), or repaglinide 4 mg (n = 146). By a last-observation carried-forward calculation, repaglinide 1 mg or 4 mg treatment decreased mean fasting plasma glucose (FPG) values (by -47 mg/dL or -49 mg/dL) while the placebo group had increased FPG values (by 19 mg/dL). For the repaglinide treatment groups at the end of the study, changes in HbA1c from baseline values ranged from 1.8 to 1.9 percentage points lower than the placebo group. There were no events of severe hypoglycemia. Nearly all hypoglycemic symptom episodes had blood glucose levels above 45 mg/dL. Repaglinide was well tolerated in a preprandial fixed-dose regimen of 1 mg or 4 mg, assigned without adjustment for clinical parameters. Nateglinide is a fast-acting insulin secretion agent that specifically targets postprandial hyperglycemia in patients with type 2 diabetes. The recent reduction in the diagnostic criteria for diabetes and improved understanding of the importance of early insulin secretion served as the rationale for this multicenter, double-blind, randomized, parallel-group, 24-wk study performed in 675 patients with type 2 diabetes but only moderately elevated fasting plasma glucose (FPG) (FPG = 7.0-8.3 mmol/liter) to assess the efficacy and safety of three fixed doses of nateglinide (30, 60, or 120 mg, with meals). A substudy of the effects on early insulin release and prandial glucose excursions following a standardized breakfast was performed in 127 subjects. Nateglinide was well tolerated and elicited a dose-dependent reduction of placebo-adjusted hemoglobin A(1c) (Delta = -0.26 to -0.39%) and FPG (Delta = -0.51 to -0.73 mmol/liter) accompanied by a dose-related increase in suspected hypoglycemic episodes. However, confirmed hypoglycemia occurred in only 5.3% of patients treated with the highest dose, compared with 1.2% in placebo-treated patients (P < 0.05). Nateglinide increased early insulin release and reduced prandial glucose excursions (P < 0.05 vs. placebo). In sum, nateglinide is a safe and effective therapeutic option for treatment of patients with mild to moderate fasting hyperglycemia.
Meglitinides may offer an alternative oral hypoglycaemic agent of similar potency to metformin, and may be indicated where side effects of metformin are intolerable or where metformin is contraindicated. However, there is no evidence available to indicate what effect meglitinides will have on important long-term outcomes, particularly mortality.