Efficacy of glimepiride in patients with poorly controlled insulin-treated type 2 diabetes mellitus

Benefits and risks of drug combination therapy for diabetes mellitus and its complications: a comprehensive review

Diabetes is a chronic metabolic disease, and its therapeutic goals focus on the effective management of blood glucose and various complications. Drug combination therapy has emerged as a comprehensive treatment approach for diabetes. An increasing number of studies have shown that, compared with monotherapy, combination therapy can bring significant clinical benefits while controlling blood glucose, weight, and blood pressure, as well as mitigating damage from certain complications and delaying their progression in diabetes, including both type 1 diabetes (T1D), type 2 diabetes (T2D) and related complications. This evidence provides strong support for the recommendation of combination therapy for diabetes and highlights the importance of combined treatment. In this review, we first provided a brief overview of the phenotype and pathogenesis of diabetes and discussed several conventional anti-diabetic medications currently used for the treatment of diabetes. We then reviewed several clinical trials and pre-clinical animal experiments on T1D, T2D, and their common complications to evaluate the efficacy and safety of different classes of drug combinations. In general, combination therapy plays a pivotal role in the management of diabetes. Integrating the effectiveness of multiple drugs enables more comprehensive and effective control of blood glucose without increasing the risk of hypoglycemia or other serious adverse events. However, specific treatment regimens should be tailored to individual patients and implemented under the guidance of healthcare professionals.

Clinical Evidence and Practice-Based Guidelines on the Utility of Basal Insulin Combined Oral Therapy (Metformin and Glimepiride) in the Current Era

BACKGROUND AND AIM

Basal insulin combined oral therapy consisting of insulin and oral anti-diabetic drugs (OADs) is recommended for type 2 diabetes uncontrolled on OADs. There is a lack of clear evidence and recommendations on the combined use of basal insulin analogues to more than one OADs (glimepiride plus metformin) in effective control of glycemic parameters and its safety in terms of reduced hypoglycemic events, weight gain and cardiovascular risk. In this context, a group of clinical experts discussed the utility of basal insulin combined oral therapy with metformin and glimepiride in the current era.

METHODS

The clinical experts discussed and provided their inputs virtually. The expert panel included clinical experts comprising endocrinologists and diabetologists from India and Nepal.

RESULTS

The panel thoroughly reviewed existing literature on the subject and proposed clinical evidence and practice-based guidelines.

CONCLUSION

These current clinical practice guidelines highlight the efficacy and safety of basal insulin combination therapy with various available basal insulins including neutral protamine hagedorn, detemir, glargine and degludec in addition to metformin and glimepiride therapy.

The Influence of Sitagliptin on Treatment-Related Quality of Life in Patients with Type 2 Diabetes Mellitus Receiving Insulin Treatment: A Prespecified Sub-Analysis

INTRODUCTION

Treatment-related quality of life (QOL) is an important aspect of diabetes management. Here, we investigated the influence of sitagliptin, a dipeptidyl peptidase-4 inhibitor, on treatment-related QOL in patients with type 2 diabetes mellitus treated with insulin.

METHODS

This was a prespecified sub-analysis of the Sitagliptin Preventive Study of Intima-Media Thickness Evaluation (SPIKE). The study population consisted of 71 subjects in the sitagliptin group, and 62 subjects in the conventional group who were treated with insulin. Patients of the sitagliptin group were started on sitagliptin in addition to ongoing insulin therapy. In the conventional group, either increasing the dose of current insulin therapy or the addition of oral hypoglycemic agents other than dipeptidyl peptidase-4 inhibitors was allowed to achieve glycemic control. Treatment-related QOL was evaluated before and 104 weeks after the initiation of the study using the Diabetes Therapy-Related QOL Questionnaire 7 (DTR-QOL7).

RESULTS

Forty-five out of 71 subjects in the sitagliptin group and 41 out of 62 subjects in the conventional group filled out the QOL questionnaire at week 104. The DTR-QOL7 score at week 104 was significantly increased from baseline in the sitagliptin group, while that in the conventional group was not changed. However, the changes in score did not differ between the two groups. Change in HbA1c was negatively associated with change in score.

CONCLUSIONS

Our data suggest that sitagliptin added to insulin treatment was comparable to other treatments in terms of its impact on treatment-related QOL.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: UMIN000007396.

FUNDING

Mitsubishi Tanabe Pharma Co., Ono Pharmaceutical Co., and Novo Nordisk.

Insulin monotherapy compared with the addition of oral glucose-lowering agents to insulin for people with type 2 diabetes already on insulin therapy and inadequate glycaemic control

BACKGROUND

It is unclear whether people with type 2 diabetes mellitus on insulin monotherapy who do not achieve adequate glycaemic control should continue insulin as monotherapy or can benefit from adding oral glucose-lowering agents to the insulin therapy.

OBJECTIVES

To assess the effects of insulin monotherapy compared with the addition of oral glucose-lowering agents to insulin monotherapy for people with type 2 diabetes already on insulin therapy and inadequate glycaemic control.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and reference lists of articles. The date of the last search was November 2015 for all databases.

SELECTION CRITERIA

Randomised controlled clinical trials of at least two months' duration comparing insulin monotherapy with combinations of insulin with one or more oral glucose-lowering agent in people with type 2 diabetes.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed risk of bias, extracted data and evaluated overall quality of the evidence using GRADE. We summarised data statistically if they were available, sufficiently similar and of sufficient quality. We performed statistical analyses according to the statistical guidelines in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We included 37 trials with 40 treatment comparisons involving 3227 participants. The duration of the interventions ranged from 2 to 12 months for parallel trials and two to four months for cross-over trials.The majority of trials had an unclear risk of bias in several risk of bias domains. Fourteen trials showed a high risk of bias, mainly for performance and detection bias. Insulin monotherapy, including once-daily long-acting, once-daily intermediate-acting, twice-daily premixed insulin, and basal-bolus regimens (multiple injections), was compared to insulin in combination with sulphonylureas (17 comparisons: glibenclamide = 11, glipizide = 2, tolazamide = 2, gliclazide = 1, glimepiride = 1), metformin (11 comparisons), pioglitazone (four comparisons), alpha-glucosidase inhibitors (four comparisons: acarbose = 3, miglitol = 1), dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) (three comparisons: vildagliptin = 1, sitagliptin = 1, saxagliptin = 1) and the combination of metformin and glimepiride (one comparison). No trials assessed all-cause mortality, diabetes-related morbidity or health-related quality of life. Only one trial assessed patients' treatment satisfaction and showed no substantial differences between the addition of either glimepiride or metformin and glimepiride to insulin compared with insulin monotherapy.Insulin-sulphonylurea combination therapy (CT) compared with insulin monotherapy (IM) showed a MD in glycosylated haemoglobin A1c (HbA1c) of -1% (95% confidence interval (CI) -1.6 to -0.5); P < 0.01; 316 participants; 9 trials; low-quality evidence. Insulin-metformin CT compared with IM showed a MD in HbA1c of -0.9% (95% CI -1.2 to -0.5); P < 0.01; 698 participants; 9 trials; low-quality evidence. We could not pool the results of adding pioglitazone to insulin. Insulin combined with alpha-glucosidase inhibitors compared with IM showed a MD in HbA1c of -0.4% (95% CI -0.5 to -0.2); P < 0.01; 448 participants; 3 trials; low-quality evidence). Insulin combined with DPP-4 inhibitors compared with IM showed a MD in HbA1c of -0.4% (95% CI -0.5 to -0.4); P < 0.01; 265 participants; 2 trials; low quality evidence. In most trials the participants with CT needed less insulin, whereas insulin requirements increased or remained stable in participants with IM.We did not perform a meta-analysis for hypoglycaemic events because the included studies used different definitions.. In most trials the insulin-sulphonylurea combination resulted in a higher number of mild episodes of hypoglycaemia, compared to the IM group (range: 2.2 to 6.1 episodes per participant in CT versus 2.0 to 2.6 episodes per participant in IM; low-quality evidence). Pioglitazone CT also resulted in more mild to moderate hypoglycaemic episodes compared with IM (range 15 to 90 episodes versus 9 to 75 episodes, respectively; low-quality evidence. The trials that reported hypoglycaemic episodes in the other combinations found comparable numbers of mild to moderate hypoglycaemic events (low-quality evidence).The addition of sulphonylureas resulted in an additional weight gain of 0.4 kg to 1.9 kg versus -0.8 kg to 2.1 kg in the IM group (220 participants; 7 trials; low-quality evidence). Pioglitazone CT caused more weight gain compared to IM: MD 3.8 kg (95% CI 3.0 to 4.6); P < 0.01; 288 participants; 2 trials; low-quality evidence. Metformin CT was associated with weight loss: MD -2.1 kg (95% CI -3.2 to -1.1), P < 0.01; 615 participants; 7 trials; low-quality evidence). DPP-4 inhibitors CT showed weight gain of -0.7 to 1.3 kg versus 0.6 to 1.1 kg in the IM group (362 participants; 2 trials; low-quality evidence). Alpha-glucosidase CT compared to IM showed a MD of -0.5 kg (95% CI -1.2 to 0.3); P = 0.26; 241 participants; 2 trials; low-quality evidence.Users of metformin CT (range 7% to 67% versus 5% to 16%), and alpha-glucosidase inhibitors CT (14% to 75% versus 4% to 35%) experienced more gastro-intestinal adverse effects compared to participants on IM. Two trials reported a higher frequency of oedema with the use of pioglitazone CT (range: 16% to 18% versus 4% to 7% IM).

AUTHORS' CONCLUSIONS

The addition of all oral glucose-lowering agents in people with type 2 diabetes and inadequate glycaemic control who are on insulin therapy has positive effects on glycaemic control and insulin requirements. The addition of sulphonylureas results in more hypoglycaemic events. Additional weight gain can only be avoided by adding metformin to insulin. Other well-known adverse effects of oral glucose-lowering agents have to be taken into account when prescribing oral glucose-lowering agents in addition to insulin therapy.

Adding glimepiride to current insulin therapy increases high-molecular weight adiponectin levels to improve glycemic control in poorly controlled type 2 diabetes

BACKGROUND

To observe the efficacy and safety of adding glimepiride to established insulin therapy in poorly controlled type 2 diabetes (T2D) and to assess the relationship of changes in the serum high-molecular weight (HMW) adiponectin levels and glycemic control after glimepiride treatment.

METHODS

Fifty-six subjects with poorly controlled insulin-treated T2D were randomly assigned to either the glimepiride-added group (the group A, n = 29) or the insulin-increasing group (the group B, n = 27) while continuing current insulin-based therapy. Glycosylated hemoglobin (HbA1c) value, daily insulin dose, body weight, waist circumference, plasma lipid concentration, serum HMW adiponectin level and the number of hypoglycemic events were evaluated before and after treatment.

RESULTS

At the end of study, insulin doses were significantly reduced, and the mean HbA1c, fasting blood glucose (FBG) and 2-hour postprandial blood glucose (P2BG) were improved greater in the group A compared with the group B. The serum HMW adiponectin levels were significantly increased in the group A compared with the group B. Most importantly, we found that changes in HbA1c were inversely correlated with changes in serum HMW adiponectin in the group A (r = -0.452, p = 0.02).

CONCLUSIONS

Adding glimepiride to current insulin treatment led to better improvement in glycemic control with a significant smaller daily insulin dose, and the increases in the serum HMW adiponectin levels may directly contribute to improvement glycemic control.

Rationale, design, and baseline characteristics of a clinical trial for prevention of atherosclerosis in patients with insulin-treated type 2 diabetes mellitus using DPP-4 inhibitor: the Sitagliptin Preventive study of Intima-media thickness Evaluation (SPIKE)

BACKGROUND

Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is currently used to achieve glycemic targets in patients with type 2 diabetes mellitus (T2DM). The addition of DPP-4 inhibitors to ongoing insulin therapy is expected to reduce insulin dosage, leading to a reduction in the frequency of hypoglycaemia and/or weight gain. Recent studies have demonstrated potential anti-atherosclerotic effects for DPP-4 inhibitors. The aim of the present ongoing study is to assess the effects of sitagliptin on the progression of atherosclerosis in patients with insulin-treated T2DM using carotid intima-media thickness (IMT), an established marker of cardiovascular disease.

METHODS AND DESIGN

The Sitagliptin Preventive study of Intima media thickness Evaluation (SPIKE) is a prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group, comparative study. Between February 2012 and September 2012, 282 participants who failed to achieve glycemic control despite insulin therapy were recruited at 12 clinics and randomly allocated to the sitagliptin group (n = 142) or the control group (n = 140). Primary outcomes are changes in maximum and mean IMT of the common carotid artery after 24-month treatment period measured by carotid arterial echography. Secondary outcomes include changes in glycemic control, parameters related to beta-cell function and diabetic nephropathy, occurrence of cardiovascular events and adverse events such as hypoglycaemia, and biochemical markers of vascular function.

DISCUSSION

The present study is designed to assess the effects of sitagliptin on the progression of carotid IMT. Results will be available in the near future, and the findings are expected to provide new strategy to prevent atherosclerosis in patients with insulin-treated T2DM.

CLINICAL TRIAL REGISTRATION

UMIN000007396.

Adding glimepiride to insulin+metformin in type 2 diabetes of more than 10 years' duration--a randomised, double-blind, placebo-controlled, cross-over study

AIMS

To investigate the effect on glycaemic control of adding glimepiride to on-going treatment with metformin and insulin in patients with known diabetes more than 10 years.

METHODS

Glimepiride 4 mg or placebo was added in randomised order for three months with a washout period of 6 weeks. All insulin regimens were allowed. Insulin doses were reduced if considered necessary. Continuous glucose monitoring was performed at the end of each period.

RESULTS

Forty-three patients, median age 66 years (46-74), diabetes duration 16 (10-30), BMI 30 kg/m(2) (25-37) and mean HbA1c 7.1% NGSP, (64 mmol/mol IFCC) were randomised. With placebo there was no change in HbA1c while a decrease of 0.6%, (7 mmol/mol IFCC) (P < 0.001), was observed with glimepiride even though insulin doses had to be reduced in 23 patients (median change 29%, range 2-100%). Minor hypoglycaemia was reported but no severe hypoglycaemic event was observed. The ratio between C-peptide/glucose increased significantly (P < 0.001) with glimepiride, both fasting and postprandially and, in a stepwise multiple regression analysis of possible predictive factors for response, a more pronounced decrease in HbA1c was associated with the magnitude of the increment in C-peptide/glucose. Older age was associated with a smaller response. Twenty-nine patients (67%) were defined as responders if this was defined as an HbA1c decrease ≥0.5% (5 mmol/mol IFCC) or an insulin dose reduction ≥20%.

CONCLUSIONS

Even after long duration of diabetes, addition of glimepiride to insulin and metformin can be effective in lowering HbA1c and/or reducing the need for exogenous insulin.

Comparison of once-daily glargine plus sulfonylurea with twice-daily 70/30 aspart premix in insulin-naive Japanese patients with diabetes

BACKGROUND

Type 2 diabetes patients insufficiently controlled with sulfonylurea (SU) are commonly treated by switching to twice-daily premix insulin replacing SU. The efficacy of glargine (GL) added on to SU compared with the premix therapy has not been analyzed in Japan.

METHODS

The open-label two-arm study was conducted in 30 type 2 diabetes patients poorly controlled [hemoglobin A(1c) (HbA(1c)) >7.5%] with SU with or without other oral hypoglycemic agents (OHAs). The GL group injected once-daily GL in addition to the OHAs. The aspart 70/30 (70/30) group discontinued SU among the OHAs and injected twice-daily 70/30. Patients were recommended either method in a block random method, and if twice-daily 70/30 was rejected, once-daily GL was selected only at the first time. The insulin dose was titrated to achieve a target fasting plasma glucose of <120 mg/dL and/or HbA(1c) of <7%.

RESULTS

Nineteen of 20 patients treated with GL and 11 of 14 patients treated with 70/30 completed the 6-month study. Mean HbA(1c) improved from 8.45% to 7.5% in the GL group and from 9.13% to 7.93% in the 70/30 group. The mean HbA(1c) decrease during 6 months was -0.95% in the GL group and -1.20% in the 70/30 group (P = 0.49). Mean insulin doses at 6 months were 12.0 units/day for the GL group and 26.7 units/day for the 70/30 group. Both therapies were well tolerated without severe hypoglycemia.

CONCLUSION

Once-daily GL injection added on to OHAs was equally safe and effective compared with twice-daily injection of aspart 70/30 premix replacing SU in type 2 patients insufficiently controlled with OHAs.