Fixed-dose single tablet antidiabetic combinations

Metformin: Therapeutic profile in the treatment of type 2 diabetes

Metformin (dimethyl-biguanide) can claim its origins in the use of Galega officinalis as a plant treatment for symptoms ascribed to diabetes. Since the first clinical use of metformin as a glucose-lowering agent in 1957, this medicine has emerged as a first-line pharmacological option to support lifestyle interventions in the management of type 2 diabetes (T2D). It acts through multiple cellular pathways, principally in the gut, liver and muscle, to counter insulin resistance and lower blood glucose without weight gain or risk of overt hypoglycaemia. Other effects include improvements in lipid metabolism, decreased inflammation and lower long-term cardiovascular risk. Metformin is conveniently combined with other diabetes medications, can be prescribed in prediabetes to reduce the risk of progression to T2D, and is used in some regions to assist glycaemic control in pregnancy. Consistent with its diversity of actions, established safety profile and cost-effectiveness, metformin is being assessed for further possible clinical applications. The use of metformin requires adequate renal function for drug elimination, and may cause initial gastrointestinal side effects, which can be moderated by taking with meals or using an extended-release formulation. Thus, metformin serves as a valuable therapeutic resource for use throughout the natural history of T2D.

Development of a Robust Control Strategy for Fixed-Dose Combination Bilayer Tablets with Integrated Quality by Design, Statistical, and Process Analytical Technology Approach

Control strategy and quality by design (QbD) are widely used to develop pharmaceutical products and improve drug quality; however, studies on fixed-dose combination (FDC) bilayer tablets are limited. In this study, the bilayer tablet consisted of high-dose metformin HCl in a sustained-release layer and low-dose dapagliflozin l-proline in an immediate-release layer. The formulation and process of each layer were optimized using the QbD approach. A d-optimal mixture design and response surface design were applied to optimize critical material attributes and critical process parameters, respectively. The robust design space was developed using Monte Carlo simulations by evaluating the risk of uncertainty in the model predictions. Multivariate analysis showed that there were significant correlations among impeller speed, massing time, granule bulk density, and dissolution in the metformin HCl layer, and among roller pressure, ribbon density, and dissolution in the dapagliflozin l-proline layer. Process analytical technology (PAT) was used with in–line transmittance near-infrared spectroscopy to confirm the bulk and ribbon densities of the optimized bilayer tablet. Moreover, the in vitro drug release and in vivo pharmacokinetic studies showed that the optimized test drug was bioequivalent to the reference drug. This study suggested that integrated QbD, statistical, and PAT approaches can develop a robust control strategy for FDC bilayer tablets by implementing real-time release testing based on the relationships among various variables.

Regimen simplification and medication adherence: Fixed-dose versus loose-dose combination therapy for type 2 diabetes

Background

Suboptimal patient adherence to pharmacological therapy of type 2 diabetes may be due in part to pill burden. One way to reduce pill burden in patients who need multiple medications is to use fixed-dose combinations. Our study aimed to compare the effects of fixed-dose combination versus loose-dose combination therapy on medication adherence and persistence, health care utilization, therapeutic safety, morbidities, and treatment modification in patients with type 2 diabetes over three years.

Methods

Using administrative data, we conducted a retrospective controlled cohort study comparing type 2 diabetes patients who switched from monotherapy to either a fixed-dose combination or a loose-dose combination. Adherence was assessed as the primary endpoint and calculated as the proportion of days covered with medication. After using entropy balancing to eliminate differences in observable baseline characteristics between the two groups, we applied difference-in-difference estimators for each outcome to account for time-invariant unobservable heterogeneity.

Results

Of the 990 type 2 diabetes patients included in our analysis, 756 were taking a fixed-dose combination and 234 were taking a loose-dose combination. We observed a statistically significantly higher change in adherence (year one: 0.22, p<0.001, year two: 0.25, p<0.001, and year three: 0.29, p<0.001) as well as higher persistence and a smaller change in the number of drug prescriptions in each of the three years in the fixed-dose combination group compared to the loose-dose combination group. The differences were most pronounced in patients who were poorly adherent, had a high pill burden, or did not have a severe concomitant disease.

Conclusion

Our results indicate that taking a fixed-dose combination can lead to a significant improvement in adherence to pharmacological therapy of type 2 diabetes compared to a loose-dose combination. In particular, these findings suggest that reducing pill burden may improve disease management among patients with more complex medication demand and patients who have demonstrated poor medication adherence.

Endometrial safety and bleeding profile of a 17β-estradiol/progesterone oral softgel capsule (TX-001HR)

Objective:

The aim of the study was to evaluate the effect of a single-capsule 17β-estradiol/progesterone (E2/P4), TX-001HR, on endometrial safety, to report on amenorrhea and bleeding patterns of users, and to identify predictors of amenorrhea.

Methods:

The REPLENISH trial (NCT01942668) evaluated use of TX-001HR in menopausal women (40-65 y) with vasomotor symptoms (VMS) and a uterus. Women were randomized to daily E2/P4 (mg/mg: 1/100, 0.5/100, 0.5/50, or 0.25/50), or placebo for 12 months. Incidence rate of endometrial hyperplasia was calculated from endometrial biopsies conducted at screening and study completion. Women reported bleeding and spotting in daily diaries. The number of bleeding and/or spotting days and the proportion of women with no bleeding or amenorrhea were compared between treatment and placebo using the Fisher exact test. Predictors of cumulative amenorrhea were assessed by univariate analyses.

Results:

Women (n = 1,835) who took at least one study dose comprised the safety population; 1,255 had baseline and 12-month biopsies and comprised the endometrial safety population. Incidence of endometrial hyperplasia was ≤0.36% with any dose of TX-001HR after 1 year of use (one-sided upper 95% confidence interval ≤4%). Cumulative amenorrhea (no bleeding/spotting) rates increased over time and were relatively high from cycle 1 to 13 with TX-001HR (56%-73%; placebo 79%; P < 0.05 except with 0.25/50 dose). Few vaginal bleeding adverse events (1.0%-4.6% TX-001HR vs 0.7% placebo) were reported and discontinuations due to bleeding were low (0.4%-1.4% vs 0%). Cumulative amenorrhea was significantly more frequent in older women, those further from their last menstrual period, and those with lower baseline E2 concentrations (all; P < 0.01).

Conclusions:

All doses of TX-001HR provided endometrial protection and were associated with an improved bleeding profile over time; older age, further last menstrual period, or lower baseline E2 may predict amenorrhea with TX-001HR.

Management of type 2 diabetes for prevention of cardiovascular disease. An expert opinion of the Italian Diabetes Society

AIMS

Type 2 diabetes mellitus is characterized by an increased risk of developing long-term cardiovascular complications. Several underlying mechanisms have been proposed for the diabetes-related increase in cardiovascular risk, i.e. chronic hyperglycemia, duration of the disease, drug-induced hypoglycemia, coexistence of multiple cardiovascular risk factors, etc. In the last few years, new pharmacological approaches capable of treating chronic hyperglycemia without increasing the risk of hypoglycemia have emerged for the treatment of diabetes.

DATA SYNTHESIS

With data mainly obtained from randomized controlled trials recruiting patients with type 2 diabetes in secondary prevention of cardiovascular disease, some of these newer antihyperglycemic drugs have shown to significantly reduce the risk of cardiovascular disease. In addition, the combined control of traditional cardiovascular risk factors, e.g. dyslipidemia, hypertension, etc., has demonstrated to be effective in reducing the burden of cardiovascular diseases in patients with type 2 diabetes.

CONCLUSIONS

In this document written by some experts of the Italian diabetes society (SID), we will focus our attention on oral antihyperglycemic agents for people with type 2 diabetes in primary or secondary prevention of cardiovascular disease, excluding for brevity the injection therapies for diabetes, such as insulin and glucagon-like peptide-1 receptor agonists.

Effects of combined 17β-estradiol and progesterone on weight and blood pressure in postmenopausal women of the REPLENISH trial

Objective:

To examine the impact of a single-capsule 17β-estradiol (E2)/progesterone (P4) on weight and blood pressure (BP) when treating moderate to severe vasomotor symptoms in postmenopausal women with a uterus.

Methods:

Healthy postmenopausal women with a uterus (aged 40-65, body mass index ≤34 kg/m², BP ≤140/90 mm Hg) were randomized to daily E2/P4 (mg/mg; 1/100, 0.5/100, 0.5/50, 0.25/50) or placebo in the phase 3 REPLENISH trial (NCT01942668). Changes in weight and BP from baseline to month 12 were evaluated. Potentially clinically important changes were defined as increases or decreases from baseline in weight by ≥15% and ≥11.3 kg, systolic BP by ≥20 mm Hg (absolute value ≥160 or ≤90 mm Hg), and diastolic BP by ≥15 mm Hg (absolute value ≥90 or ≤60 mm Hg).

Results:

Overall mean changes in weight and BP from baseline to month 12 with E2/P4 were modest and generally not statistically or clinically significant versus placebo. Incidence of potentially clinically important changes was low for weight (E2/P4 vs placebo: 1.1-2.6% vs 2.2%), systolic BP (0.3-1.1% vs 1.1%), and diastolic BP (1.4-4.2% vs 3.2%). A small number of women had treatment-related, treatment-emergent adverse events of weight gain (1.4-2.6% vs 1.3%) or hypertension (0.2-1.2% vs 0%). Few women who discontinued E2/P4 had weight gain (1.6%) or hypertension (0.6%) as a primary reason. Efficacy profile on VMS was consistent with previous findings and not modified by body mass index.

Conclusions:

Twelve-month use of E2/P4 had no clinically meaningful impact on weight or BP in postmenopausal women of the REPLENISH study.

Efficacy and safety of dapagliflozin plus saxagliptin versus insulin glargine over 52 weeks as add-on to metformin with or without sulphonylurea in patients with type 2 diabetes: A randomized, parallel-design, open-label, Phase 3 trial

AIM

Efficacy and safety of dapagliflozin plus saxagliptin (DAPA + SAXA) were compared with insulin glargine (INS) in patients with type 2 diabetes (T2D) in a 52-week extension study.

MATERIALS AND METHODS

This international Phase 3 study randomized adults with T2D on metformin with/without sulphonylurea. They received DAPA + SAXA or INS for 24 weeks (short-term) with a 28-week (long-term) extension. Week 52 exploratory endpoints included adjusted mean change from baseline in glycated haemoglobin A_1c (HbA1c) and body weight, and a proportion of patients achieving optimal glycaemic response without hypoglycaemia and without requiring rescue medication.

RESULTS

Of the 1163 patients enrolled, 643 received treatment; 600 (DAPA + SAXA, 306; INS, 294) entered the long-term phase. At 52 weeks, HbA1c [adjusted least squares (LS) mean; 95% confidence interval (CI)] decreased more with DAPA + SAXA (-1.5% [-1.6%, -1.4%]) than with INS (-1.3% [-1.4%, -1.1%]); the LS mean difference (95% CI) was -0.25% (-0.4%, -0.1%; P = 0.009). Total body weight reduced with DAPA + SAXA [LS mean (95% CI): -1.8 kg (-2.4, -1.3)] and increased with INS [LS mean (95% CI): +2.8 kg (2.2, 3.3)]. More patients on DAPA + SAXA (17.6%) achieved HbA1c <7.0% without hypoglycaemia versus those on INS (9.1%). Rescue medication was required by 77 patients (23.8%) and 97 patients (30.4%) in the DAPA + SAXA and INS groups, respectively.

CONCLUSION

DAPA + SAXA treatment was non-inferior to INS in reducing HbA1c and body weight, and in achieving optimal glycaemic control without hypoglycaemia in patients with T2D 52 weeks after initiation.

Formulation, Development and Scale-Up of Fixed-Dose Combination Tablets Containing Zidovudine, Lamivudine and Nevirapine

Background:

The development of antiretroviral associations in a single dosage form aims to ensure improved efficacy, low costs and better adherence to treatment.

Objective:

This work performed the pharmacotechnical development, coating, and stability studies of fixed-dose combination tablets of zidovudine, lamivudine and nevirapine (300 + 200 + 150 mg, respectively).

Methods:

Qualitative and quantitative planning of diluents (101 and 250 microcrystalline cellulose, spray-dried monohydrate lactose and corn starch) and coating polymers (Opadry white II HP® and Instacoat Aqua Moistshield II®) were analyzed, and direct compression (DC) and wet granulation (WG) methods were tested aiming the development of the pharmaceutical form. Quality control was carried out according to the specifications set by official compendia. The chosen formulation was scaled-up and the industrial batches were submitted to accelerated and long-term stability studies.

Results:

The batches obtained by WG met the requirements, using 101 microcrystalline cellulose, corn starch and Opadry white II HP® as excipients. The DC trial was not possible due to the need of a greater ratio of excipients to improve formulation properties.

Conclusion:

Thus, this study brings a new therapeutic alternative for HIV treatment, contributing to the development of another possibility to simplify drug administration.

Novel univariate spectrophotometric determination of the recently released solid dosage form comprising dapagliflozin and saxagliptin via factorized response spectra: Assessment of the average content and dosage unit uniformity of tablets

Dapagliflozin (DPF) and saxagliptin (SXG) are currently co-formulated in a tablet dosage form which is prescribed to improve glycemic control. The absorption spectra of DPF and SXG were highly overlapped which completely hindered their simultaneous estimation at their λ_max 224 nm and 209 nm, respectively. Thus, in this work three smart and simple univariate spectrophotometric methods were originally established and validated for the first time in order to quantitatively estimate DPF and SXG in bulk forms and in combined pharmaceutical formulation without the requirement for any initial separation or treatment. These methods are; factorized zero order method (FZM), factorized derivative method (FDM) and factorized ratio difference method (FRM). These methods were capable of determining DPF and SXG over the range of 2.5-50.0 μg/mL and 2.5-60.0 μg/mL, respectively. All the developed methods are based on a novel and unique approach for the spectral recovery of unresolved spectra named; factorized response spectrum (FRS). The exclusivity of the FRS originates from its ability to completely resolve the cited drugs in the mixture and retrieve their original spectra. Selectivity of all proposed methods was assessed by comparing the obtained results of the mixture analysis with those of the pure powdered drugs. Validation of the newly developed methods was applied as recommended by the ICH demonstrating acceptable accuracy and precision. In general, these methods could be effectively employed for the routine quality control investigation of bulk materials and available market formulations.

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.

Evaluation of novel TGR5 agonist in combination with Sitagliptin for possible treatment of type 2 diabetes

TGR5 is a member of G protein-coupled receptor (GPCR) superfamily, a promising molecular target for metabolic diseases. Activation of TGR5 promotes secretion of glucagon-like peptide-1 (GLP-1), which activates insulin secretion. A series of 2-thio-imidazole derivatives have been identified as novel, potent and orally efficacious TGR5 agonists. Compound 4d, a novel TGR5 agonist, in combination with Sitagliptin, a DPP-4 inhibitor, has demonstrated an adequate GLP-1 secretion and glucose lowering effect in animal models, suggesting a potential clinical option in treatment of type-2 diabetes.

Metformin: historical overview

Metformin (dimethylbiguanide) has become the preferred first-line oral blood glucose-lowering agent to manage type 2 diabetes. Its history is linked to Galega officinalis (also known as goat's rue), a traditional herbal medicine in Europe, found to be rich in guanidine, which, in 1918, was shown to lower blood glucose. Guanidine derivatives, including metformin, were synthesised and some (not metformin) were used to treat diabetes in the 1920s and 1930s but were discontinued due to toxicity and the increased availability of insulin. Metformin was rediscovered in the search for antimalarial agents in the 1940s and, during clinical tests, proved useful to treat influenza when it sometimes lowered blood glucose. This property was pursued by the French physician Jean Sterne, who first reported the use of metformin to treat diabetes in 1957. However, metformin received limited attention as it was less potent than other glucose-lowering biguanides (phenformin and buformin), which were generally discontinued in the late 1970s due to high risk of lactic acidosis. Metformin's future was precarious, its reputation tarnished by association with other biguanides despite evident differences. The ability of metformin to counter insulin resistance and address adult-onset hyperglycaemia without weight gain or increased risk of hypoglycaemia gradually gathered credence in Europe, and after intensive scrutiny metformin was introduced into the USA in 1995. Long-term cardiovascular benefits of metformin were identified by the UK Prospective Diabetes Study (UKPDS) in 1998, providing a new rationale to adopt metformin as initial therapy to manage hyperglycaemia in type 2 diabetes. Sixty years after its introduction in diabetes treatment, metformin has become the most prescribed glucose-lowering medicine worldwide with the potential for further therapeutic applications.

Pharmacokinetic drug evaluation of saxagliptin plus dapagliflozin for the treatment of type 2 diabetes

INTRODUCTION

Combining a dipeptidyl peptidase-4 inhibitor and a sodium-glucose cotransporter type 2 inhibitor is an attractive option to treat hyperglycaemia in type 2 diabetes. Areas covered: The saxagliptin plus dapagliflozin combination is carefully analysed, focusing on: 1) pharmacokinetic properties, 2) pharmacodynamics data, and 3) results of randomised controlled trials (dual combination versus either monotherapy, sequential therapy saxagliptin added to dapagliflozin or dapagliflozin added to saxagliptin). Expert opinion: Pharmacokinetic findings demonstrate the absence of drug-drug interaction and the bioequivalence of the FDC compared with separated tablets. Pharmacodynamic observations confirm a complementary mode of action of the two agents. Dual saxagliptin-dapagliflozin therapy is more potent than either monotherapy. It may be used as an initial combination, although this approach remains debatable and should probably be reserved in case of high glycated hemoglobin, or a stepwise strategy, according to a personalized approach. The developed saxagliptin-dapagliflozin FDC may simplify anti-hyperglycemic therapy and improve drug compliance.

Lack of a Pharmacokinetic Interaction Between Saxagliptin and Dapagliflozin in Healthy Subjects: A Randomized Crossover Study

PURPOSE

This single-dose, open-label, randomized, 3-period, 3-treatment crossover drug-drug interaction study was conducted to evaluate differences in the pharmacokinetic properties of saxagliptin and dapagliflozin when coadministered.

METHODS

Healthy subjects (N = 42) were randomized to receive saxagliptin 5 mg alone, dapagliflozin 10 mg alone, or saxagliptin 5 mg plus dapagliflozin 10 mg coadministered; there was a washout period of ≥6 days between treatments. Serial blood samples for determining saxagliptin, 5-hydroxy saxagliptin (5-OH saxagliptin; major active metabolite) and dapagliflozin plasma concentrations and pharmacokinetic parameters were collected before and up to 60 hours after the dose. No interaction was to be concluded if the 90% CIs for the geometric mean ratios of the combination compared with each drug given alone for Cmax and AUCinf were within 0.80 to 1.25.

FINDINGS

The results indicated that dapagliflozin had no effect on the pharmacokinetic properties of saxagliptin, 5-OH saxagliptin, or saxagliptin total active moiety and vice versa. The 90% CIs for Cmax and AUCinf for all comparisons were contained entirely within the 0.80 to 1.25 equivalence intervals. Other pharmacokinetic parameters (apparent oral clearance or half-life) of saxagliptin or dapagliflozin were similar when each medicine was administered alone or when coadministered. No safety profile or tolerability findings of concern were observed during the study. All adverse events were mild, and no serious adverse events were reported.

IMPLICATIONS

These data indicate that coadministration of saxagliptin and dapagliflozin exhibits no pharmacokinetic interaction and is well tolerated. ClinicalTrials.gov identifier: NCT01662999.

Bioequivalence of saxagliptin/dapagliflozin fixed-dose combination tablets compared with coadministration of the individual tablets to healthy subjects

Saxagliptin and dapagliflozin are individually indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. The bioequivalence of saxagliptin/dapagliflozin 2.5/5 mg and 5/10 mg fixed-dose combination (FDC) tablets compared with coadministration of the individual tablets and the food effect on both strengths of saxagliptin/dapagliflozin FDCs were evaluated in this open-label, randomized, single-dose crossover study. Healthy subjects were randomized to saxagliptin 2.5 mg + dapagliflozin 5 mg fasted, 2.5/5 mg FDC fasted, 2.5/5 mg FDC fed (Cohort 1) or saxagliptin 5 mg + dapagliflozin 10 mg fasted, 5/10 mg FDC fasted, 5/10 mg FDC fed (Cohort 2). Serial blood samples for pharmacokinetics of saxagliptin and dapagliflozin were obtained predose and up to 60 h postdose. Bioequivalence of FDC tablets versus individual components was concluded if the 90% CIs for FDC to individual component geometric mean ratios of C max, AUC 0-T, and AUC inf of both analytes were between 0.80 and 1.25. Seventy-two subjects were randomized; 71 (98.6%) completed the study. Saxagliptin/dapagliflozin 2.5/5 mg and 5/10 mg FDC tablets were bioequivalent to the individual tablets administered concomitantly. Food had no clinically meaningful effect on saxagliptin or dapagliflozin overall systemic exposure. Saxagliptin/dapagliflozin FDC tablets were bioequivalent to coadministration of the individual components in healthy subjects under fasted conditions and food had no clinically meaningful effect on bioavailability.

Population pharmacokinetic modeling and noncompartmental analysis demonstrated bioequivalence between metformin component of metformin/vildagliptin fixed-dose combination products and metformin immediate-release tablet sourced from various countries

Metformin is the first-line pharmacotherapy choice for treating type-2 diabetes mellitus, alone or in combination with other antidiabetic drugs. During the development of immediate-release (IR) metformin containing novel fixed-dose combination (FDC) products, several health-authorities require sponsors to demonstrate bioequivalence between FDC products and the country-sourced metformin for market approval. Eight bioequivalence studies that compared metformin/vildagliptin FDC product (test) to metformin IR tablet sourced from various countries (reference) were conducted. A population pharmacokinetic (PPK) analysis of pooled metformin concentration-time data was performed to evaluate whether country-sourced metformin is a significant covariate. The PPK analysis demonstrated that there was no clinically relevant effect of metformin source or race/ethnicity on metformin pharmacokinetics. Also, noncompartmental analysis conducted showed that 90%CI of geometric mean ratios of test to reference metformin formulations, calculated for maximum-concentration and exposure parameters, were within the 80%-125% criteria, indicating comparable metformin exposure regardless of the country-sourced metformin IR formulation. These results are consistent with the biopharmaceutics properties of metformin and provide scientific evidence that after assessing in vitro dissolution of novel FDC formulation, additional bioequivalence studies with multiple countries' reference products may not be required once bioequivalence is established with 1 country-sourced IR metformin formulation.

Pharmacokinetics and clinical evaluation of the alogliptin plus pioglitazone combination for type 2 diabetes

INTRODUCTION

Type 2 diabetes is a complex disease with multiple defects, which generally requires a combination of several pharmacological approaches to reach glucose control targets. A unique fixed-dose combination combines a thiazolidinedione (pioglitazone) and a dipeptidyl peptidase-4 inhibitor (alogliptin).

AREA COVERED

An extensive literature search was performed to analyze the pharmacokinetics of pioglitazone and alogliptin when used separately and in combination as well as to summarize clinical and toxicological considerations about the combined therapy.

EXPERT OPINION

Pioglitazone, a potent insulin sensitizer, and alogliptin, an incretin-based agent that potentiates post-meal insulin secretion and reduces glucagon secretion, have complementary mechanisms of action. The clinical efficacy of a combined therapy is superior to any single therapy in patients treated with diet or with metformin (with or without sulphonylurea). These two drugs can be administered once daily, with or without a meal. No clinically relevant pharmacokinetic interactions between the two agents have been described and the fixed-dose combination has shown bioequivalence with alogliptin and pioglitazone given separately. Combining alogliptin with pioglitazone does not alter the safety profile of each compound. Weight gain observed with pioglitazone may be limited with the addition of alogliptin. The concern of an increased risk of heart failure remains to be better investigated.

Application of HPLC mixed-mode chromatography in determining radiochemical purity of [(14) C] labeled metformin hydrochloride

Metformin is currently prescribed worldwide to treat type 2 diabetes, and therefore, radiolabeled [(14) C] metformin is often prepared for clinical comparisons of new drug candidates. Prior to using the radiolabeled metformin, the purity needs to be determined to ensure the quality of the material. While typical reversed-phase LC methods are often the first choice for purity analysis, they are not suitable for this determination because the compound is poorly retained under these conditions. Mixed-mode chromatography has been demonstrated to overcome these retention issues, and therefore, this methodology was utilized for the purity determination of radiolabeled metformin.

Management of diabetes medications for patients undergoing ambulatory surgery

A stress-free actively managed perioperative experience is crucial to successful ambulatory surgery for diabetes patients. Practitioners who integrate diabetes treatment regimens into their perioperative management can facilitate a good outcome, smooth recovery, and rapid return to normal life. Hypoglycemia, hyperglycemia, and glucose variability must be avoided and patients should be maintained near their usual blood glucose.

Potentiation of insulin secretion and improvement of glucose intolerance by combining a novel G protein-coupled receptor 40 agonist DS-1558 with glucagon-like peptide-1 receptor agonists

G protein-coupled receptor 40 (GPR40) is a Gq-coupled receptor for free fatty acids predominantly expressed in pancreatic β-cells. In recent years, GPR40 agonists have been investigated for use as novel therapeutic agents in the treatment of type 2 diabetes. We discovered a novel small molecule GPR40 agonist, (3S)-3-ethoxy-3-(4-{[(1R)-4-(trifluoromethyl)-2,3-dihydro-1H-inden-1-yl]oxy}phenyl)propanoic acid (DS-1558). The GPR40-mediated effects of DS-1558 on glucose-stimulated insulin secretion were evaluated in isolated islets from GPR40 knock-out and wild-type (littermate) mice. The GPR40-mediated effects on glucose tolerance and insulin secretion were also confirmed by an oral glucose tolerance test in these mice. Furthermore, oral administration of DS-1558 (0.03, 0.1 and 0.3mg/kg) significantly and dose-dependently improved hyperglycemia and increased insulin secretion during the oral glucose tolerance test in Zucker fatty rats, the model of insulin resistance and glucose intolerance. Next, we examined the combination effects of DS-1558 with glucagon like peptide-1 (GLP-1). DS-1558 not only increased the glucose-stimulated insulin secretion by GLP-1 but also potentiated the maximum insulinogenic effects of GLP-1 after an intravenous glucose injection in normal Sprague Dawley rats. Furthermore, the glucose lowering effects of exendin-4, a GLP-1 receptor agonist, were markedly potentiated by the DS-1558 (3mg/kg) add-on in diabetic db/db mice during an intraperitoneal glucose tolerance test. In conclusion, our results indicate that add-on GPR40 agonists to GLP-1 related agents might be a potential treatment compared to single administration of these compounds. Therefore the combinations of these agents are a novel therapeutic option for type 2 diabetes.

Efficacy and safety of linagliptin in Hispanic/Latino patients with type 2 diabetes mellitus: a pooled analysis from six randomized placebo-controlled phase 3 trials

OBJECTIVE

The number of individuals diagnosed with type 2 diabetes mellitus is expected to rise disproportionately in Hispanic/Latino populations. We therefore aimed to assess the efficacy and safety of the dipeptidyl peptidase-4 inhibitor linagliptin specifically in Hispanic/Latino patients with type 2 diabetes mellitus.

RESEARCH DESIGN AND METHODS

Data from 745 patients who self-identified their ethnicity as Hispanic or Latino were pooled from six randomized, placebo-controlled phase 3 trials. Participants received linagliptin (5 mg/day) or placebo as monotherapy, or in combination with other oral antidiabetes drugs for 18 or 24 weeks.

RESULTS

The placebo-adjusted mean change (95% CI) in glycated hemoglobin from baseline (mean 8.2%) was -0.63% (-0.77 to -0.48; p<0.0001) at week 18, and -0.58% (-0.74 to -0.42; p<0.0001) at week 24. The placebo-adjusted mean change (95% CI) in fasting plasma glucose from baseline was -11.7 mg/dL (-19.3 to -4.0; p=0.0028) at week 18 and -14.1 mg/dL (-22.0 to -6.3; p=0.0004) at week 24. Hypoglycemia incidence was 17.4% with linagliptin and 21% with placebo. In patients not receiving concomitant sulfonylurea, the hypoglycemia incidence was 10.1% with linagliptin and 19.4% with placebo. The overall incidence of adverse events (AEs), drug-related AEs, and serious AEs with linagliptin was similar to placebo (AEs 67.6% vs 68.9%; drug-related AEs 15.1% vs 18.7%; serious AEs 3.6% vs 3.0%). The mean body weight remained unchanged in both groups.

CONCLUSIONS

In Hispanic/Latino patients with inadequately controlled type 2 diabetes mellitus, linagliptin provided clinically meaningful improvements in glycemic control without weight gain or increased risk of hypoglycemia.

Adherence to therapies in patients with type 2 diabetes

Adherence to therapy is defined as the extent to which a person's behavior in taking medication, following a diet, and/or executing lifestyle changes, corresponds with agreed recommendations from a healthcare provider. Patients presenting with type 2 diabetes mellitus are initially encouraged to maintain a healthy diet and exercise regimen, followed by early medication that generally includes one or more oral hypoglycemic agents and later may include an injectable treatment. To prevent the complications associated with type 2 diabetes, therapy frequently also includes medications for control of blood pressure, dyslipidemia and other disorders, since patients often have more than three or four chronic conditions. Despite the benefits of therapy, studies have indicated that recommended glycemic goals are achieved by less than 50% of patients, which may be associated with decreased adherence to therapies. As a result, hyperglycemia and long-term complications increase morbidity and premature mortality, and lead to increased costs to health services. Reasons for nonadherence are multifactorial and difficult to identify. They include age, information, perception and duration of disease, complexity of dosing regimen, polytherapy, psychological factors, safety, tolerability and cost. Various measures to increase patient satisfaction and increase adherence in type 2 diabetes have been investigated. These include reducing the complexity of therapy by fixed-dose combination pills and less frequent dosing regimens, using medications that are associated with fewer adverse events (hypoglycemia or weight gain), educational initiatives with improved patient-healthcare provider communication, reminder systems and social support to help reduce costs. In the current narrative review, factors that influence adherence to different therapies for type 2 diabetes are discussed, along with outcomes of poor adherence, the economic impact of nonadherence, and strategies aimed at improving adherence.

Clinical Benefits of Single‐tablet Regimens

Since the advent of highly active antiretroviral therapy, considerable progress has been made in the treatment of HIV infection. Single-tablet regimens (STRs) represent substantial improvements in the treatment of HIV infection by providing all of the components of a safe and effective antiretroviral therapy regimen in a single pill that is dosed once daily, thereby allowing for simpler and more convenient treatment. Of the three FDA-approved STRs currently available in the USA, two consist of combinations of two nucleoside reverse transcriptase inhibitors (NRTIs) and one non-nucleoside reverse transcriptase inhibitor (NNRTI), efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF) and emtricitabine/rilpivirine/tenofovir disoproxil fumarate (FTC/RPV/TDF), while the third and newest STR consists of two NRTIs plus an integrase strand transfer inhibitor (INSTI), elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF). Large clinical trials and retrospective analyses have demonstrated the advantages of these STRs over other treatment regimens, including greater adherence and persistence, better health outcomes, improved patient preference and quality of life and reduced healthcare resource utilization. Because of the demonstrated advantages of STR therapies in the management of HIV and successes in other disease areas using coformulated medications, it may be beneficial to develop future STRs for the treatment of other chronic diseases.

Combine and conquer: advantages and disadvantages of fixed-dose combination therapy

The majority of patients with type 2 diabetes mellitus (T2DM) do not achieve the glycaemic goals recommended by leading diabetes organizations using monotherapy alone, and often require multiple antihyperglycaemic agents to achieve glycaemic control. Fixed-dose combination (FDC) therapies offer a means to simplify complex treatment regimens, and have several advantages that help patients reach their glycaemic goals. In this review, four key benefits are identified and discussed in support of FDCs for treatment of patients with T2DM: (i) Greater efficacy compared with higher dose monotherapy, (ii) Reduced risk of adverse reactions relative to higher dose monotherapy, (iii) Lower overall costs and (iv) Improved medication concordance. Given these advantages, the place of fixed combination therapy in the course of treatment is discussed. Establishing a therapeutic strategy that incorporates fixed combination therapy (including combinations with insulin) will simplify the treatment of diabetes, ideally resulting in improved medication concordance, clinical outcomes and quality of life for patients with T2DM.

A multicenter, phase III evaluation of the efficacy and safety of a new fixed-dose pioglitazone/glimepiride combination tablet in Japanese patients with type 2 diabetes

BACKGROUND

This study aimed to determine the efficacy and safety of pioglitazone/glimepiride as a fixed-dose combination (FDC) in Japanese patients with type 2 diabetes.

SUBJECTS AND METHODS

In this multicenter, phase III, open-label evaluation, eligible patients had to have a glycosylated hemoglobin (HbA(1c)) level of ≥7.4% and <10.4% halfway through a 4-week run-in period while being treated with glimepiride 1 or 3 mg once daily plus diet and exercise. At baseline, patients were assigned to 8 weeks of treatment with pioglitazone/glimepiride (15 mg/1 mg) FDC once daily (group A; n=31) or pioglitazone/glimepiride (30 mg/3 mg) FDC once daily (group B; n=31) according to their glimepiride dose during run-in.

RESULTS

Pioglitazone/glimepiride significantly reduced the mean HbA(1c) level from baseline (primary end point) by 0.59±0.556% in group A (P<0.0001) and by 0.55±0.637% in group B (P<0.0001). Corresponding reductions in the mean fasting blood glucose level were 12.5±21.67 mg/dL (P=0.0032) and 29.1±35.38 mg/dL (P<0.0001). Significant alterations from baseline to week 8 in either one or both treatment groups were also noted for the following parameters: 1,5-anhydroglucitol, glycoalbumin, triglycerides, high-density lipoprotein cholesterol, and free fatty acid levels. Five patients in group A (16.1%) had five treatment-related adverse events, and 10 patients in group B (32.3%) had 13 such events; all events were mild.

CONCLUSIONS

Pioglitazone/glimepiride as a FDC (30 mg/3 mg and 15 mg/1 mg once daily) significantly improved glycemic control and lipid profiles and was well tolerated in Japanese patients with type 2 diabetes.

Saxagliptin plus metformin combination therapy

Metformin is considered to be the first-line drug therapy for the management of Type 2 diabetes. Incretin-based therapies, and especially dipeptidyl peptidase-4 inhibitors, offer new opportunities after failure of metformin. An extensive literature search was performed to analyze all clinical trials combining saxagliptin with metformin. Saxagliptin and metformin may be administered together, either separately or in fixed-dose combination, as saxagliptin added to metformin or as an initial combination. Saxagliptin and metformin are not prone to pharmacokinetic drug-drug interactions and fixed-dose combination allows dosing of one single pill (Kombiglyze^® XR) or two pills (Komboglyze^®) per day. Both compounds exert pharmacodynamic complementary actions. Their coadministration improves blood glucose control (fasting plasma glucose, postprandial glucose and glycated hemoglobin) more potently than either compound separately. Tolerance is good without hypoglycemia, weight gain and further increase in metformin-related gastrointestinal adverse events. The combination saxagliptin plus metformin may be used as first-line or second-line therapy in the management of Type 2 diabetes.

Patient adherence to medication requirements for therapy of type 2 diabetes

Type 2 diabetes is a complex, progressive endocrine and metabolical disease that typically requires substantial lifestyle changes and multiple medications to lower blood glucose, reduce cardiovascular risk and address comorbidities. Despite an extensive range of available and effective treatments, < 50% of patients achieve a glycaemical target of HbA(1c) < 7.0% and about two-thirds die of premature cardiovascular disease. Adherence to prescribed therapies is an important factor in the management of type 2 diabetes that is often overlooked. Inadequate adherence to oral antidiabetes agents, defined as collecting < 80% of prescribed medication, is variously estimated to apply to between 36% and 93% of patients. All studies affirm that a significant proportion of type 2 diabetes patients exhibit poor adherence that will contribute to less than desired control. Identified factors that impede adherence include complex dosing regimens, clinical inertia, safety concerns, socioeconomic issues, ethnicity, patient education and beliefs, social support and polypharmacy. This review explores these factors and potential strategies to improve adherence in patients with type 2 diabetes.

Overcoming challenges in Type 2 diabetes management to improve patient outcomes

As obesity and Type 2 diabetes mellitus reach epidemic proportions worldwide, glycemic control and prevention of complications have become even more critical. We searched studies published between January 2006 and January 2010 to identify and discuss the challenges facing healthcare professionals and patients in reaching glycemic targets. MEDLINE and Derwent Drug File searches were conducted with the following search terms: Type 2 diabetes mellitus, medication adherence, antihyperglycemic agents, glucose control, and clinical inertia. In this article we will outline the commonly used medications and present the advantages and disadvantages of each class of drug. Additionally, we will present the dipeptidyl peptidase-4 inhibitors and their place in the treatment of patients with Type 2 diabetes mellitus.

Fixed-dose combination therapies in the management of hyperglycaemia in Type 2 diabetes: an opportunity to improve adherence and patient care

The medication-taking behaviour of patients may be key to avoiding the serious long-term micro- and macrovascular complications of Type 2 diabetes. However, the polypharmacy often required to achieve good metabolic control can be a significant barrier to adequate adherence. Reducing treatment complexity can be achieved through the use of single-tablet fixed-dose combinations of two oral hypoglycaemic agents. Studies to date suggest that this approach can significantly improve adherence over separate tablet dual therapy and has the potential to improve metabolic and clinical outcomes. A range of fixed-dose combination oral hypoglycaemic agents in several different dosage strengths are available and the strategies for optimal implementation of these options continue to evolve. This article describes the extent and consequences of poor adherence to oral hypoglycaemic agents in Type 2 diabetes and discusses the potential contribution of fixed-dose combinations to the provision of improved care.

Review of Medications Used in the Treatment of Diabetes Mellitus

Objective:

To review the pathophysiology of diabetes mellitus and outline currently available medications used in its treatment.

Data Sources:

A MEDLINE/PubMed search (1966-December 2009) was conducted for English-language articles using the terms diabetes mellitus, pharmacotherapy, metformin, thiazolidinedione, sulfonylurea, meglitinide, α-glucosidase inhibitor, DPP-4 inhibitor, colesevelam, bromocriptine, exenatide, pramlintide, and insulin. Book chapters relevant to the pathophysiology and pharmacologic treatment of diabetes were also searched.

Study Selection and Data Extraction:

Articles and chapters pertinent to the pharmacologic management of diabetes mellitus were reviewed.

Data Synthesis:

Type 1 diabetes is characterized by an absolute lack of insulin production by the β-cells of the pancreas, requiring insulin therapy. Type 2 diabetes is characterized by both insulin resistance and a relative or absolute lack of insulin secretion. Because type 2 diabetes involves both insulin resistance and decreased insulin production over time, people with type 2 diabetes can be treated with a variety of drugs currently on the market. Therapies currently on the market include metformin, thiazolidinediones, sulfonylureas, meglitinides, α-glucosidase inhibitors, DPP-4 inhibitors, colesevelam, bromocriptine, exenatide, pramlintide, and insulin.

Conclusions:

Given the multitude of medications available for the treatment of diabetes, it is important that pharmacy technicians and pharmacists be aware of the various agents currently on the market. With a solid foundation of knowledge regarding diabetes medications, a huge impact can be made on the quality of care of the customers and patients the pharmacy serves.

Perioperative management of ambulatory surgical patients with diabetes mellitus

PURPOSE OF REVIEW

Patients with diabetes frequently present for ambulatory surgery concomitant with the rise in incidence of the disease. This review will examine recent evidence on glucose control, the harmful effects of hyperglycemia, fluctuations of blood glucose, and hypoglycemia, as well as treatments and medications utilized for type 1 and type 2 diabetes mellitus. Based on this evidence, a strategy for perioperative decision making for the diabetic patient undergoing ambulatory surgery will be presented.

RECENT FINDINGS

New studies question the practice of intensive control of blood glucose in critically ill patients. Also, tight control of HbA1c levels in patients with type 2 diabetes may have associated cardiovascular risks. Glucose fluctuations and hypoglycemia may pose greater risks to patients than elevated glucose itself. New medications and insulin regimens make perioperative blood glucose control easier now than in the past.

SUMMARY

The ambulatory anesthesiologist, with a dedication to low-impact practices and emphasis on rapid recovery, provides an ideal environment of care for the patient with diabetes. This review will examine issues and concerns with management of the patient with diabetes undergoing ambulatory surgery and address them in a step-wise strategy for care, including recommendations for perioperative insulin administration.