Long-term effect of combination therapy with mitiglinide and once daily insulin glargine in patients who were successfully switched from intensive insulin therapy in short-term study

Strategies in synthetic design and structure-activity relationship studies of novel heterocyclic scaffolds as aldose reductase-2 inhibitors

Heterocyclic scaffolds of natural as well as synthetic origin provide almost all categories of drugs exhibiting a wide range of pharmacological activities, such as antibiotics, antidiabetic and anticancer agents, and so on. Under normal homeostasis, aldose reductase 2 (ALR2) regulates vital metabolic functions; however, in pathological conditions like diabetes, ALR2 is unable to function and leads to secondary diabetic complications. ALR2 inhibitors are a novel target for the treatment of retinopathy (cataract) influenced by diabetes. Epalrestat (stat), an ALR2 inhibitor, is the only drug candidate that was approved in the last four decades; the other drugs from the stat class were retracted after clinical trial studies due to untoward iatrogenic effects. The present study summarizes the recent development (2014 and onwards) of this pharmacologically active ALR2 heterocyclic scaffold and illustrates the rationale behind the design, structure-activity relationships, and biological studies performed on these molecules. The aim of the current review is to pave a straight path for medicinal chemists and chemical biologists, and, in general, to the drug discovery scientists to facilitate the synthesis and development of novel ALR2 inhibitors that may serve as lead molecules for the treatment of diseases related to the ALR2 enzyme.

Simplification of complex insulin regimens using canagliflozin or liraglutide in patients with well-controlled type 2 diabetes: A 24-week randomized controlled trial

AIMS/INTRODUCTION

We investigated the potential use of canagliflozin, in comparison with liraglutide, as an alternative to bolus insulin in patients with well-controlled type 2 diabetes mellitus receiving multiple daily insulin injection therapy.

MATERIALS AND METHODS

In 40 patients, with glycated hemoglobin (HbA1c) levels <7.5% controlled by multiple daily insulin injection therapy, all bolus insulin was randomly switched to canagliflozin (100 mg/day) or liraglutide (0.3-0.9 mg/day) for 24 weeks. Basal insulin was continued with dose adjustment according to a predefined algorithm. The end-points were the change in the HbA1c level, glycemic variability assessed by continuous glucose monitoring, body mass index, insulin dose, quality of life (QOL) and safety assessments. Factors influencing the changes in QOL were also assessed using a simple regression analysis.

RESULTS

The change in HbA1c from baseline was comparable between the treatments. Both treatments maintained the HbA1c level to the baseline levels with stable glucose variability and no severe hypoglycemia for 24 weeks, decreased total insulin dose, and significantly increased the QOL score. The change in QOL was significantly associated with injection frequency.

CONCLUSIONS

For patients with well-controlled type 2 diabetes mellitus, under the support of basal insulin, complex insulin regimens can be simplified by replacing all bolus insulin with once-daily canagliflozin or liraglutide, which improves patients' QOL.

Use of Insulin Glargine 100 U/mL for the Treatment of Type 2 Diabetes Mellitus in East Asians: A Review

Insulin glargine (IGlar) 100 U/mL (IGlar-100) is widely used in East Asian countries for the treatment of type 2 diabetes mellitus (T2DM) and is the gold standard of basal insulin treatment. In this review we summarize key information about clinical experience with IGlar-100 in East Asian patients with T2DM, including findings from clinical trials and postmarketing studies. We also provide recommendations and opinions on the optimal use of IGlar-100 in this population. The findings from the studies highlighted in our review indicate that IGlar-100 can be a suitable treatment option for East Asians with T2DM, from initial therapy in combination with oral antihyperglycemic medications through to different combinations and intensification models. FUNDING: Eli Lilly and Company.

The vasorelaxant effect of mitiglinide via activation of voltage-dependent K+ channels and SERCA pump in aortic smooth muscle

AIMS

The vasorelaxant effects of the anti-diabetic drug, mitiglinide in phenylephrine (Phe)-pre-contracted aortic rings were examined.

MATERIALS AND METHODS

Arterial tone measurement was performed in aortic smooth muscle cells.

KEY FINDINGS

Mitiglinide dose-dependently induced vasorelaxation. Application of the large-conductance Ca²⁺-activated K⁺ (BK_Ca) channel blocker paxilline, inwardly rectifying K⁺ (Kir) channel blocker Ba²⁺, and ATP-sensitive K⁺ (K_ATP) channel blocker glibenclamide did not affect the vasorelaxant effect of mitiglinide. However, application of the voltage-dependent K⁺ (Kv) channel blocker 4-AP, effectively inhibited mitiglinide-induced vasorelaxation. Although pretreatment with the Ca²⁺ channel blocker nifedipine did not alter the mitiglinide-induced vasorelaxation, pretreatment with the sarcoplasmic/endoplasmic reticulum Ca²⁺-ATPase (SERCA) pump inhibitor thapsigargin and cyclopiazonic acid reduced the vasorelaxant effect of mitiglinide. In addition, the vasorelaxant effect of mitiglinide was not affected by the inhibitors of adenylyl cyclase, protein kinase A, guanylyl cyclase, or protein kinase G. Elimination of the endothelium and inhibition of endothelium-dependent vasorelaxant mechanisms also did not change the vasorelaxant effect of mitiglinide.

SIGNIFICANCE

We proposed that mitiglinide induces vasorelaxation via activation of Kv channels and SERCA pump. However, the vasorelaxant effects of mitiglinide did not involve other K⁺ channels, Ca²⁺ channels, PKA/PKG signaling pathways, or the endothelium.

Add-on treatment with mitiglinide improves residual postprandial hyperglycemia in type 2 diabetic patients receiving the combination therapy with insulin glargine and sitagliptin

The combination of a dipeptidyl peptidase-4 (DPP-4) inhibitor and a long-acting insulin analogue is widely used in clinical practice. However, some patients fail to achieve lower postprandial hyperglycemia. Mitiglinide, a short-acting insulinotropic sulfonylurea receptor ligand, is effective for postprandial hyperglycemia. Recently, it has been reported that the combination therapy of mitiglinide with a DPP-4 inhibitor could improve glycemic control. However, the efficacy of those under long-acting insulin analogue therapy remains to be investigated. Thus, we conducted a prospective single-center study of eight Japanese patients with type 2 diabetes mellitus receiving mitiglinide added to the combination therapy of sitagliptin and insulin glargine, and evaluated its efficacy and safety by continuous glucose monitoring (CGM). Participants' (four men and four women) mean age was 70.3 ± 10.6 years. Their mean body mass index, HbA1c level, and urinary C-peptide level were 22.0 ± 2.8 kg/m(2), 9.2 ± 1.2%, and 50.0 ± 31.4 μg/day, respectively. CGM showed that as compared with the combination of only sitagliptin and insulin glargine, mitiglinide in combination with sitagliptin and insulin glargine significantly reduced glycemic fluctuation indices, total area for the range of 24-h glycemic fluctuations (p = 0.04), mean amplitude of glycemic excursions (p = 0.03), and the proportion of time in hyperglycemia (p = 0.02) without significant difference in the proportion of time in hypoglycemia (p = 0.18). Hence, we have demonstrated the efficacy and safety of the add-on treatment with mitiglinide in type 2 diabetic patients, receiving the combination therapy of sitagliptin and insulin glargine.

A prospective, randomized, multicenter trial comparing the efficacy and safety of the concurrent use of long-acting insulin with mitiglinide or voglibose in patients with type 2 diabetes

This trial was conducted to compare the efficacy and safety of combination therapy with basal insulin glargine plus mitiglinide to that of basal insulin glargine plus voglibosein patients with type 2 diabetes. This was a 20-week, randomized, multicenter non-inferiority trial. Patients with HbA1c levels over 7.0% were randomly assigned to receive either mitiglinide (10 mg tid) or voglibose (0.2 mg tid) concurrent with insulin glargine for 16 weeks after a 4-week of basal insulin glargine monotherapy. The intention-to-treat population included 156 patients; 79 were placed in the mitiglinide group, and 77 were placed in the voglibose group. At 20 weeks, there was no significant difference between the mitiglinide group and the voglibose group in terms of the mean HbA1c level or the mean decrease of the HbAlc level from baseline (-0.9% [-7.5 mmol/mol] and -0.7%, [-5.3 mmol/mol] respectively). The mean fasting plasma glucose level and data of self-monitoring blood glucosewere significantly decreased from baseline to week 20 in both groups, but there was no significant difference between the two groups. The changes in the basal insulin requirements of each group were not significant. The prevalence of adverse events and the risk of hypoglycemia were similar for both groups. Combination therapy with mitiglinide plus basal insulin glargine was non-inferior to voglibose plus basal insulin glargine in terms of the effect on overall glycemic control.

Effect of the combination of mitiglinide and metformin on glycemic control in patients with type 2 diabetes mellitus

Aims/Introduction:  Mitiglinide is the newest drug in the meglitinide family. It increases the early-phase insulin release through rapid association-dissociation kinetics in the pancreatic β cells. The efficacy and safety of adding meglitinide to metformin monotherapy in patients with type 2 diabetes are unknown.

MATERIALS AND METHODS

  We carried out a prospective, randomized, multicenter trial to assess the efficacy and safety of combined treatment with mitiglinide and metformin for patients with type 2 diabetes who showed inadequate glycemic control with metformin monotherapy. Subjects with glycated hemoglobin (HbA1c) >7.0% after an 8-week metformin run-in phase were randomized to a 16-week trial phase with metformin plus mitiglinide (Met + Mit) or metformin plus placebo (Met + Pcb).

RESULTS

  Compared with the Met + Pcb group, the Met + Mit group showed a greater reduction in HbA1c (-0.7 ± 0.6%vs-0.4 ± 0.7%, P = 0.002), fasting plasma glucose (-0.77 ± 1.76 mmol/L vs-0.05 ± 1.60 mmol/L, P = 0.015) and 2-h postprandial glucose (-3.76 ± 3.57 mmol/L vs-0.84 ± 3.07 mmol/L, P < 0.0001). The proportion of the patients who achieved the target HbA1c value of <7% at the end of the study was also higher in the Met + Mit group than the Met + Pcb group (49.3%vs 28.8%, P = 0.016). There were no differences in the adverse event rates between groups.

CONCLUSIONS

  Combination therapy with metformin and mitiglinide is effective and safe for the treatment of patients with type 2 diabetes who have inadequate glycemic control with metformin monotherapy. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00023.x, 2010).

Improvement of both fasting and postprandial glycemic control by the two-step addition of miglitol and mitiglinide to basal insulin therapy: a pilot study

BACKGROUND

Combination therapy consisting of basal insulin and oral hypoglycemic agents (OHAs) is effective for the treatment of type 2 diabetes (T2DM) that cannot be adequately controlled using OHAs alone. Though basal insulin with metformin or sulfonylurea is an effective therapy, it cannot reduce postprandial glycemia without the risk of hypoglycemia. We examined a two-step regimen consisting of the addition of postprandial hypoglycemic agents (an alpha-glucosidase inhibitor and a glinide) in patients whose T2DM was poorly controlled using basal insulin therapy.

METHODS

Inpatients between the ages of 30-79 years who had T2DM and an HbA1c level of more than 7.0% were recruited. The patients were treated with once-daily insulin glargine with or without metformin, depending on the patient's age and renal function. Insulin glargine was titrated to achieve a target fasting glucose level of 70-130 mg/dL as a first step (STEP0). If the 2-hour postprandial glucose (PBG) level was higher than the target of 180 mg/dL, miglitol treatment (150 mg/day) was initiated, with dose adjustments (75-225 mg) allowed depending on abdominal symptoms and the PBG (STEP1). If the PBG of the patients remained higher than the target after 3 days of treatment, mitiglinide (30 mg/day, titrated up to 60 mg) was added (STEP2). We then evaluated the proportion of patients who achieved the target PBG before and after the two-step regimen. Continuous Glucose Monitoring (CGM) was performed throughout the two-step protocol in most of the patients.

RESULTS

Of the 16 patients who were recruited (median age, 67.0 [58.0-71.0] years; body mass index, 25.0 [22.0-27.9] kg/m(2); HbA1c level at admission, 9.1% [8.35-10.4%]), 1 patient (6.25%) achieved the target PBG at STEP 0 and 14 patients (87.5%) had achieved the target PBG at the end of the treatment protocol (P = 0.002). CGM showed a significant decrease in the glucose level at each step of the protocol. The standard deviations in the CGM glucose levels for 24 hours, MAGE, and M-value also improved.

CONCLUSIONS

The two-step addition of postprandial hypoglycemic agents to basal insulin therapy is potentially effective and safe for decreasing both the fasting and postprandial glucose levels.

Postprandial hyperglycemia and endothelial function in type 2 diabetes: focus on mitiglinide

The risk of cardiovascular complication in a diabetes patient is similar to that in a nondiabetic patient with a history of myocardial infarction. Although intensive control of glycemia achieved by conventional antidiabetic agents decreases microvascular complications such as retinopathy and nephropathy, no marked effect has been reported on macrovascular complications or all-cause mortality. Evidence from VADT, ACCORD, and ADVANCE would suggest that glycemic control has little effect on macrovascular outcomes. Moreover, in the case of ACCORD, intensive glycemic control may be associated with an increased risk of mortality. There is sufficient evidence that suggests that postprandial hyperglycemia may be an independent risk factor for cardiovascular disease in diabetes patients. However, there are no prospective clinical trials supporting the recommendation that lowering postprandial blood glucose leads to lower risk of cardiovascular outcomes. Mitiglinide is a short-acting insulinotropic agent used in type 2 diabetes treatment. It has a rapid stimulatory effect on insulin secretion and reduces postprandial plasma glucose level in patients with type 2 diabetes. Because of its short action time, it is unlikely to exert adverse effects related to hypoglycemia early in the morning and between meals. Mitiglinide reduces excess oxidative stress and inflammation, plays a cardioprotective role, and improves postprandial metabolic disorders. Moreover, mitiglinide add-on therapy with pioglitazone favorably affects the vascular endothelial function in type 2 diabetes patients. These data suggest that mitiglinide plays a potentially beneficial role in the improvement of postprandial hyperglycemia in type 2 diabetes patients and can be used to prevent cardiovascular diseases. Although the results of long-term, randomized, placebo-controlled trials for determining the cardiovascular effects of mitiglinide on clinical outcomes are awaited, this review is aimed at summarizing substantial insights into this topic.

Mitiglinide: a novel agent for the treatment of type 2 diabetes mellitus

OBJECTIVE

To review the pharmacology, pharmacokinetics, efficacy, and safety of mitiglinide, a rapid-acting insulin secretion-stimulating agent to determine its potential role in therapy for the treatment of type 2 diabetes mellitus.

DATA SOURCES

A MEDLINE search (1966-May 2010) was conducted for English-language, human studies using the terms mitiglinide, KAD 1229, S 21403, and meglitinide analogs. Abstracts presented at the American Association and European Association for the Study of Diabetes annual meetings from 2005 to 2009 were also evaluated for relevant data.

STUDY SELECTION AND DATA EXTRACTION

Articles pertinent to the pharmacology, pharmacokinetics, efficacy, and safety of mitiglinide were reviewed.

DATA SYNTHESIS

Mitiglinide has been shown through small clinical studies (N <400) to modestly decrease hemoglobin A(1c), postprandial hyperglycemia, and oxidative stress and inflammatory markers associated with postprandial hyperglycemia. Mitiglinide exerts its hypoglycemic activity by closing adenosine triphosphate (ATP)-sensitive potassium channels in the β-islet cells of the pancreas. This agent has a rapid onset and short duration of action, mimicking a physiologic pattern of insulin release in nondiabetic people. Studies suggest a starting dose of 5 mg 3 times daily with meals and a maximum dose of 20 mg 3 times daily. Overall, mitiglinide is well tolerated, with the most common adverse effect being hypoglycemia.

CONCLUSIONS

Mitiglinide is the third agent in the class of meglitinides that targets postprandial hyperglycemia. Because of a more intensive dosing regimen, potential cost, and lack of studies assessing the clinical impact of mitiglinide therapy on oxidative stress and inflammatory markers secondary to postprandial hyperglycemia, we cannot recommend this therapy over currently approved therapies.

Long-term efficacy of insulin glargine after switching from NPH insulin as intensive replacement of basal insulin in Japanese diabetes mellitus. Comparison of efficacy between type 1 and type 2 diabetes (JUN-LAN Study 1.2)

To assess and compare the efficacy and safety of insulin glargine as intensive replacement of basal insulin in Japanese patients with type 1 (n = 72) and type 2 (n = 46) diabetes, we switched their intensive insulin regimen from NPH plus regular or rapid-acting insulin to glargine plus bolus insulin, which included regular and rapid-acting insulin, and recorded changes in glycemic control and frequency of hypoglycemia for 18 months. The dose titration of basal and bolus insulin was based on home self-monitored blood glucose measurements and monthly HbA(1C). Mean HbA(1C) level was improved significantly at 3 months after switching to glargine plus bolus insulin regimen and these effects continued for 18 months in both type 1 and type 2 diabetes patients (HbA(1C) level: type 1: baseline 8.9 +/- 2.6%, 18 months 7.8 +/- 1.5% (p<0.05), type 2: baseline 8.2 +/- 2.6%, 18 months 7.7 +/- 1.5%. Body weight was slightly but significantly increased at 18 months only in type 2 diabetes. Total daily bolus insulin doses were not changed but basal insulin could be increased significantly after switching regimens in both types diabetes compared with baseline. The frequency of mild to moderate hypoglycemia (self-assisted episodes, blood glucose <70 mg/dl) was marginally lower with glargine but not significantly. Self-monitored fasting blood glucose level was significantly improved after switching in type 2 diabetes. Patients with the worst HbA(1C) level at baseline exhibited more than 10% improvement in HbA(1C) level after switching both type 1 and type 2 diabetes. The HbA(1C) levels of the effectively treated patients were comparable to those of ineffectively treated ones at 6 months and the same improvement was seen at 18 months. Our results suggested that insulin glargine is more effective than NPH insulin as intensive replacement of basal insulin, particularly in those Japanese patients with difficult glycemic control with NPH insulin, equally in both type 1 and type 2 diabetes.