Four-Year Durability of Initial Combination Therapy with Sitagliptin and Metformin in Patients with Type 2 Diabetes in Clinical Practice; COSMIC Study

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.

Therapeutic efficacy and safety of initial triple combination of metformin, sitagliptin, and lobeglitazone in drug-naïve patients with type 2 diabetes: initial triple study

OBJECTIVE

To compare the efficacy and safety of an initial triple therapy using metformin, a dipeptidyl peptidase-4 (DPP4) inhibitor, and thiazolidinedione with a stepwise approach using sulfonylurea and metformin in new-onset, drug-naïve patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Among drug-naïve patients with 9.0%-12.0% glycated hemoglobin (HbA1c) but no hyperglycemic symptoms, 100 subjects who started triple medications (metformin 1000 mg/day, sitagliptin 100 mg/day, and lobeglitazone 0.5 mg/day) were selected as an initial triple therapy group. Age and body mass index-matched subjects (n=100) who started glimepiride (≥2 mg/day with uptitration) and metformin (≥1000 mg/day with uptitration) were selected as a conventional therapy group. We investigated changes in HbA1c level, dynamic indexes for insulin sensitivity and β-cell function, and hypoglycemia.

RESULTS

After 12 months of treatment, HbA1c levels decreased significantly in both groups: from 10.7%±1.0% to 6.7%±1.3% in the triple group, and from 10.5%±1.0% to 7.3%±1.2% in the conventional therapy group. At 12 months, achievement of the HbA1c target (<7.0%) was higher in the triple group than in the conventional group (70% vs 52%, p<0.01). Dynamic indexes related to β-cell function and insulin sensitivity improved, and albuminuria reduced significantly only in the triple group. Hypoglycemia was more common in the conventional group.

CONCLUSIONS

Initial triple combination therapy with the DPP4 inhibitor, metformin, and thiazolidinedione showed a higher achievement of the target HbA1c goal with a lower risk of hypoglycemia, better restoration of β-cell function, and multiple metabolic benefits, implying durable glycemic control. This strategy may be useful for patients presenting with type 2 diabetes and high HbA1c levels.

Sitagliptin vs. pioglitazone as add-on treatments in patients with uncontrolled type 2 diabetes on the maximal dose of metformin plus sulfonylurea

AIMS

To compare the efficacy of sitagliptin versus pioglitazone as add-on drugs in patients with poorly controlled diabetes with metformin and sulfonylureas.

METHODS

This is a randomized, open-label, parallel assignment clinical trial. Patients who had inadequate glycemic control [7% (53 mmol/mol) ≤ A1C < 11% (97 mmol/mol)] despite a minimum 6-month period of active treatment with metformin 2000 mg/day plus gliclazide 240 mg/day were enrolled in the study. HbA1C, fasting blood glucose (FBG), fasting plasma lipid parameters [total cholesterol (TC0, low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C)], systolic and diastolic blood pressure (SBP, DBP), weight, waist circumference, and body mass index were measured at baseline and after 17, 34, and 52 weeks of treatment. Generalized estimating equation analysis was done to compare treatment groups for continuous efficacy parameters.

RESULTS

No significant difference in HbA1C reduction was observed between the treatment groups during the study course. (P = 0.149, adjusted P = 0.434; coefficient - 0.11 ± 0.08). The FBG (P = 0.032; coefficient 7.44 ± 3.48), HDL-C (P = 0.001; coefficient - 2.69 ± 0.83), TG (P = 0.027; coefficient 12.63 ± 5.71) and SBP (P < 0.001; coefficient 5.43 ± 1.26) changes from baseline, and weight gain were greater in the pioglitazone group. The mean changes in LDL-C and TC from baseline to week 52 were greater in the sitagliptin group (P = 0.034; coefficient - 7.40 ± 3.50, P = 0.013; coefficient - 7.16 ± 2.88, respectively).

CONCLUSION

Sitagliptin and pioglitazone were equally effective in improvement of HbA1C. There were some differences in terms of lipid indices, weight gain, and SBP. The current study confirmed that both sitagliptin and pioglitazone are effective treatment options and the decision should be made for each individual based on the baseline characteristics.

Effects of metformin and alogliptin on body composition in people with type 2 diabetes

AIMS/INTRODUCTION

The aim of the present study was to investigate the effects of metformin and a dipeptidyl peptidase-4 inhibitor, alogliptin, on body composition in a 12-week randomized add-on trial in Japanese participants with type 2 diabetes.

MATERIALS AND METHODS

A total of 84 participants with poorly controlled type 2 diabetes undergoing antidiabetic therapy were randomly assigned to receive alogliptin (25 mg, once daily) or metformin (1,000 mg, twice daily) for 12 weeks. The primary efficacy end-point was body composition. The secondary end-points included factors associated with decreased bodyweight.

RESULTS

Compared with the baseline values, alogliptin significantly increased bodyweight (66.5 ± 19.2 to 67.6 ± 19.3 kg), body mass index (BMI; 25.4 ± 6.1 to 25.8 ± 6.3 kg/m2 ) and fat mass (20.3 ± 12.8 to 21.8 ± 14.5 kg), whereas metformin had no significant effect on body composition. Alogliptin was inferior to metformin in reducing bodyweight (0.84 ± 1.57 vs -0.35 ± 1.53 kg, P = 0.002), BMI (0.34 ± 0.69 to -0.15 ± 0.56 kg/m2 , P = 0.002) and fat mass (1.49 ± 5.06 vs -0.04 ± 1.81 kg, P = 0.042). BMI at baseline was associated with changes in bodyweight negatively in the metformin group and positively in the alogliptin group.

CONCLUSIONS

Metformin and alogliptin exert opposite effects on bodyweight in type 2 diabetes patients who are overweight. The higher the BMI, the more metformin reduces bodyweight and alogliptin increases weight.

Factors involved in decreasing the therapeutic effect of sitagliptin: a subanalysis of the JAMP study

Objective

As a subanalysis of the Januvia Multicenter Prospective Trial in Type 2 Diabetes (JAMP study), we examined factors that decreased blood glucose control effect of sitagliptin after 3 months and patients requiring an addition or increase of diabetes treatment.

Methods

We selected patients in whom glycated hemoglobin (HbA1c) levels decreased by month 3 after initiation of sitagliptin treatment and conducted two analyses: (1) in patients who did not change drugs until month 12, we compared changes in HbA1c levels between concomitant drugs and examined factors that decreased blood glucose control effect of sitagliptin; (2) compared changes in HbA1c levels and backgrounds between patients who did and did not require an addition to or increased dose of the antidiabetic agent.

Results

Four hundred and ninety-eight patients were chosen. In 369 patients without drug change until month 12, changes in HbA1c levels during months 3-12 were not significantly different among concomitant drugs; factors causing rebound HbA1c were smoking and weight gain. Patient characteristics were compared between those who did and did not require an additional drug or a dose increase (n = 114) (n = 384). Drug changes were associated with longer disease duration, younger age, higher rate of smoking, and higher degree of insulin resistance but not with concomitantly administered drugs.

Conclusion

Smoking and weight gain were factors that decreased the effect of sitagliptin on reducing blood glucose levels. Differences in concomitant drugs did not affect sitagliptin's effects on glycemic control. A dose increase or the addition of the antidiabetic drug was not associated with concomitant drugs.

Pharmacokinetics of Metformin in Combination With Sitagliptin in Adult Horses After Enteral Administration

Insulin dysregulation (ID) is a common metabolic disorder in horses. Recently, incretin hormone release has been suggested to be involved in ID in horses. In human medicine, metformin and sitagliptin are commonly used in combination for metabolic syndrome. This combination could be useful in treating ID in horses. However, no pharmacokinetics data have been reported in this species. The objective of the present study was to establish the plasma concentration-time profile and to derive pharmacokinetics data for a combination of metformin and sitagliptin in horses after enteral administration. Six healthy adult Purebred Spanish horses were used. A metformin (15 mg/kg) plus sitagliptin (1.5 mg/kg) preparation was administered by intragastric route (IG) as an enteral solution. Blood samples were collected from 0 to 48 hours after IG drug administration. Plasma concentrations of metformin and sitagliptin were measured using high performance liquid chromatography methods. The t_½λz for metformin was 2.9 hours and for sitagliptin 21 hours. The C_max was 442 ± 84 mg/L within 0.9 hours for metformin and 94 ± 14 mg/L within 1.3 hours for sitagliptin. No adverse effects were observed, and the combination of metformin and sitagliptin was well tolerated. Therefore, these results suggest that metformin plus sitagliptin might be a combination to consider in horses with ID. Additional studies are needed to establish the effectiveness and tolerance in equids affected by endocrine disorders.

Initial combination therapy with vildagliptin plus metformin in drug-naïve patients with T2DM: a 24-week real-life study from Asia

AIMS

To assess the effectiveness and safety of vildagliptin/metformin initial combination therapy in drug-naïve patients with type 2 diabetes mellitus (T2DM).

METHODS

INITIAL was a 24-week prospective, observational study in T2DM patients with glycated hemoglobin (HbA1c) ≥ 7.5%, and prescribed vildagliptin/metformin as initial combination therapy. The primary endpoint was change in HbA1c from baseline to week 24. Key secondary endpoints were HbA1c change from baseline to week 12, proportion of patients achieving HbA1c ≤7.0%, change in body weight at 12 and 24 weeks, change in HbA1c by sub-groups (baseline HbA1c, age, body mass index [BMI], dosage strength, co-morbidities) from baseline to week 24, and safety.

RESULTS

A total of 532 patients were enrolled. The mean age, HbA1c, and BMI were 49.6 ± 11.27 years, 9.3 ± 1.57%, and 26.7 ± 4.50 kg/m², respectively. Cardiovascular risk factors present at baseline were dyslipidemia (30.1%), hypertension (29.7%), and obesity (20.9%). The mean reductions in HbA1c from baseline to week 12 (-1.6 ± 1.59%) and 24 (-1.9 ± 1.70%) were statistically significant (p < .001). At 24 weeks, 39.6% of patients achieved HbA1c ≤ 7.0%, and the mean body weight reduction was -1.1 ± 2.62 kg. HbA1c reductions were consistently seen from baseline to weeks 12 and 24 in the various sub-groups. Overall, 48 (9.0%) patients reported adverse events, including one hypoglycemic episode. There were no serious adverse events or deaths.

CONCLUSIONS

Overall, in a relatively young drug-naïve T2DM Asian study population with high baseline HbA1c and often associated with cardiovascular risk factors, vildagliptin/metformin combination therapy was associated with significant and clinically relevant HbA1c reduction from baseline. This effect was seen at week 12, was maintained over 24 weeks, and was accompanied by good tolerability.

Combination Glucose-Lowering Therapy Plans in T2DM: Case-Based Considerations

Type 2 diabetes mellitus (T2DM) is a complex disease, and while lifestyle interventions remain the cornerstone of therapy, most patients will also require pharmacotherapy. Current diabetes treatment guidelines and algorithms recommend an individualized approach to setting glycemic goals and selecting treatment. Although a single antihyperglycemic agent may be appropriate as the initial T2DM pharmacotherapy, the progressive nature of the disease due to declining pancreatic β-cell function will result in the vast majority of T2DM patients eventually requiring two or more antihyperglycemic agents. The American Association of Clinical Endocrinologists/American College of Clinical Endocrinology T2DM management algorithm recommends initial dual agent combination therapy when a single agent is unlikely to achieve their target glycemia, i.e., for those patients with an HbA1c ≥ 7.5 and an individualized HbA1c target of < 7.5%. The American Diabetes Association Standards of Care recommend combination pharmacotherapy for those patients presenting with very elevated HbA1c levels (e.g., ≥ 9% and < 10%). Metformin (if well tolerated and not contraindicated) is the initial pharmacologic choice for most patients; selection of another antihyperglycemic agent to the regimen will depend on the presence of atherosclerotic cardiovascular disease and other patient-specific factors (e.g., age, known duration of T2DM, history of or risk for hypoglycemia and/or adverse consequences from hypoglycemia, other comorbidities, and available resources), along with drug-specific factors (e.g., risk for hypoglycemia, potential effects on weight, drug adverse event profiles, and cost). Combination therapy may be administered as a multi-pill regimen, a single-pill combination (i.e., fixed-dose combination oral therapy), or as a combination of oral and/or injectable therapies. This paper provides two illustrative case presentations to demonstrate how current treatment recommendations and algorithms can be used to guide the selection of non-insulin-based combination therapy for patients with T2DM in primary care settings and discusses the relative merits of several possible approaches for each patient.

FUNDING

Boehringer Ingelheim Pharmaceuticals, Inc.

Efficacy and safety of liraglutide versus sitagliptin both in combination with metformin in patients with type 2 diabetes: A systematic review and meta-analysis

BACKGROUND

The aim of this systematic review was to evaluate the efficacy and safety of liraglutide versus sitagliptin both in combination with metformin in patients with type 2 diabetes and provide reference basis for rational use of clinical drugs.

METHODS

Several databases were searched, including Web of science, PubMed, Cochrane library, CNKI, and Wanfang database. Only randomized controlled trials (RCTs) of liraglutide versus sitagliptin both in combination with metformin up to 31 August 2016 were included. Data were extracted independently by 2 reviewers, and a fixed or random effects model were used to analyze outcomes that were expressed as odds ratio (OR) or mean difference (MD) and 95% confidence intervals (95% CIs) for different situations.

RESULTS

Five RCTs involving 1440 participants were included. Compared with sitagliptin combination with metformin group, participants' treatment with 1.2 mg and 1.8 mg liraglutide with metformin could significantly lower the level of glycosylated hemoglobin (HbA1c) (P < .00001, MD = -0.35, 95% CI -0.51 to -0.20). Moreover, patients with 1.8 mg liraglutide group had significant body weight loss (P < .00001, MD = -1.12, 95% CI -1.54 to -0.70). However, there were no obvious differences in cutting down the systolic blood pressure and diastolic blood pressure between liraglutide-metformin and sitagliptin-metformin groups. The incidence of gastrointestinal problems was significantly higher than sitagliptin with metformin groups.

CONCLUSION

The results of this meta-analysis indicated that Liraglutide added on to metformin therapy could significantly lower the level of HbA1c and increase body weight loss. Meanwhile, the adverse reactions such as gastrointestinal problems were common in the liraglutide treatment group. Thus, this will provide an important reference for the treatment of patients with type 2 diabetes.