Pharmacokinetics, Pharmacodynamics, and Safety of Single Dose HSK7653 Tablets in Chinese Subjects with Normal or Impaired Renal Function

OBJECTIVE

HSK7653 is a novel, ultralong-acting dipeptidyl peptidase-4 (DPP-4) inhibitor, promising for type 2 diabetes mellitus with a dosing regimen of once every 2 weeks. This trial investigates the pharmacokinetics (PKs), pharmacodynamics (PDs),and safety of HSK7653 in outpatients with normal or impaired renal function.

METHODS

This is a multicenter, open-label, nonrandomized, parallel-controlled phase I clinical study that investigates the pharmacokinetic profiles of HSK7653 after a single oral administration in 42 subjects with mild (n = 8), moderate (n = 10), severe renal impairment (n = 10), and end-stage renal disease (without dialysis, n = 5) compared with matched control subjects with normal renal function (n = 9). Safety was evaluated throughout the study, and the pharmacodynamic effects were assessed on the basis of a DPP-4 inhibition rate.

RESULTS

HSK7653 exposure levels including the maximum plasma concentration (Cmax), area under the plasma concentration-time curve from zero to last time of quantifiable concentration (AUC0-t), and area under the plasma concentration-time curve from zero to infinity (AUC0-inf) showed no significant differences related to the severity of renal impairment. Renal clearance (CLR) showed a certain downtrend along with the severity of renal impairment. The CLR of the group with severe renal impairment and the group with end-stage renal disease were basically similar. The DPP-4 inhibition rate-time curve graph was similar among the renal function groups. All groups had favorable safety, and no serious adverse events occurred.

CONCLUSIONS

HSK7653 is a potent oral DPP-4 inhibitor with a long plasma half-life, supporting a dosing regimen of once every 2 weeks. Impaired renal function does not appear to impact the pharmacokinetic and pharmacodynamic properties of HSK7653 after a single administration in Chinese subjects. HSK7653 is also well tolerated without an increase in adverse events with increasing renal impairment. These results indicate that dose adjustment of HSK7653 may not be required in patients with renal impairment.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05497297.

A Quantitative Systems Pharmacology Model of the Incretin Hormones GIP and GLP1, Glucagon, Glucose, Insulin, and the Small Molecule DPP-4 Inhibitor, Linagliptin

In the current study, we established a comprehensive quantitative systems pharmacology (QSP) model using linagliptin as the model drug, where drug disposition, drug intervention on dipeptidyl peptidase-4 (DPP-4), glucose-dependent insulinotropic peptide (GIP), Glucagon-like peptide-1 (GLP-1), glucagon, glucose, and insulin are integrated together with the cross talk and feedback loops incorporated among the whole glycemic control system. In the final linagliptin QSP model, the complicated disposition of linagliptin was characterized by a 2-compartment pharmacokinetic (PK) model with an enterohepatic cycling (EHC) component as well as target-mediated drug disposition (TMDD) processes occurring in both tissues and plasma, and the inhibitory effect of linagliptin on DPP-4 was determined by the linagliptin-DPP-4 complex in the central compartment based on target occupancy principle. The integrated GIP-GLP1-glucagon-glucose-insulin system contains five indirect response models as the "skeleton" structure with 12 feedback loops incorporated within the glucose control system. Our model adequately characterized the substantial nonlinear PK of linagliptin, time course of DPP-4 inhibition, as well as the kinetics of GIP, GLP-1, glucagon, and glucose simultaneously in humans. Our model provided valuable insights on linagliptin pharmacokinetics/pharmacodynamics and complicated glucose homeostasis. Since the glucose regulation modeling framework within the QSP model is "drug-independent", our model can be easily adopted by others to evaluate the effect of other DPP-4 inhibitors on the glucose control system. In addition, our QSP model, which contains more components than other reported glucose regulation models, can potentially be used to evaluate the effect of combination antidiabetic therapy targeting different components of glucose control system.

A systematic review on the clinical pharmacokinetics of vildagliptin in healthy and disease populations

INTRODUCTION

Vildagliptin, a dipeptidyl peptidase-4 inhibitor, is indicated to cure type 2 diabetes mellitus (T2DM). This systematic literature search aims to assess the current knowledge about the clinical pharmacokinetics (PK) of vildagliptin to provide recommendations for clinical use to prevent the harmful effects of this drug.

METHODS

The PubMed, Science Direct, EBSCO, Cochrane Central Register of Controlled Trials, and Google Scholar databases were screened for articles related to the clinical PK of vildagliptin using systematic search strategies.

RESULTS

The literature search identified 2118 records, among which 28 were subsumed in this systematic review that fulfilled the inclusion standards.

CONCLUSIONS

This systematic review can help dose optimization among critically ill patients (e.g. renal impairment) without exposing them to the drug's toxic effects.

Dose decision of HSK7653 oral immediate release tablets in specific populations clinical trials based on mechanistic physiologically-based pharmacokinetic model

HSK7653, an oral dipeptidyl peptidase-4 inhibitor administered every 2 weeks, is a candidate for the treatment of type 2 diabetes mellitus. The major elimination pathway of HSK7653 in vivo is renal excretion, and hepatic metabolism and fecal excretion of unchanged compound contribute less to the systemic clearance of HSK7653. Considering the disposition characteristics and the potential indication population of HSK7653, evaluating the HSK7653 exposure in patients with renal impairment and geriatric populations is a prerequisite for bringing more benefits to the patients. Here, a PBPK model was developed based on in vitro experimental results, such as dissolution, permeability, and metabolism, and the in vivo renal clearance, to evaluate the effects of physiological factors and food on HSK7653 exposure in specific populations, including adult and elder individuals with renal impairment and geriatric populations. Simulation results showed that the AUC of HSK7653 increased by 46%, 82%, and 129% in adult patients with mild, moderate, and severe renal impairment, and by 56%, 78%, and 101% in patients aged 65-75, 75-85 and 85-95 years, respectively. The AUC increased in the range of 62%-83%, 98%-133%, and 153%-195% in elderly patients (65-95 years) with mild, moderate, and severe renal impairment, respectively. Moreover, two different absorption model development methods (dissolution profile method and the diffusion layer model method) predicted that food had no effect on the exposure of the same simulated population. Since the predicted AUC of HSK7653 at the 10 mg dose in various specific populations was still within the relatively flat results of the exposure-response analysis, the 10 mg dose of HSK7653 was first used to explore the exposure in the renal impairment population (CTR20221952).

Pharmacokinetics of exogenous GIP(1-42) in C57Bl/6 mice; Extremely rapid degradation but marked variation between available assays

Like other peptide hormones, glucose-dependent insulinotropic polypeptide (GIP) is rapidly cleared from the circulation. Dipeptidyl peptidase-4 (DPP-4) is known to be involved. Information on the overall pharmacokinetics of GIP in rodents is, however, lacking. We investigated the pharmacokinetics of exogenous GIP after intravenous, subcutaneous and intraperitoneal injection with and without DPP-4 inhibition in conscious female C57Bl/6 mice. Secondly, we compared total and intact GIP levels measured by an in-house RIA and commercially available ELISA kits to determine the suitability of these methods for in vivo and in vitro measurements. GIP half-life following intravenous injection amounted to 93 ± 2 s, which was extended to 5 ± 0.6 min by inhibition of DPP-4. Intact GIP levels following subcutaneous and intraperitoneal GIP administration were approximately 15 % of total GIP. The area under the curve of intact GIP (GIP exposure) following GIP injection was significantly increased by DPP-4 inhibition, whereas total GIP levels remained unchanged. We found significant variation between measurements of total, but not intact GIP performed with our in-house RIA and ELISAs in samples obtained after in vivo administration of GIP. Different preanalytical sample preparation (EDTA plasma, heparin plasma, assay buffer and PBS) significantly influenced results for all ELISA kits used. Thus, in experiments involving exogenous GIP(1-42) administration in mice, it is important to consider that this will result in a very low ratio of intact:total peptide but co-administration of a DPP-4 inhibitor greatly elevates this ratio. Furthermore, for comparison of GIP levels, it is essential to maintain uniformity concerning assay methodology and sample preparation.

Dipeptidyl peptidase-4 inhibition to prevent progression of calcific aortic stenosis

OBJECTIVE

To evaluate whether the use of dipeptidyl peptidase-4 (DPP-4) inhibitors and their cardiac tissue distribution profile and anticalcification abilities are associated with risk of aortic stenosis (AS) progression.

METHODS

Out of the five different classes of DPP-4 inhibitors, two had relatively favourable heart to plasma concentration ratios and anticalcification ability in murine and in vitro experiments and were thus categorised as 'favourable'. We reviewed the medical records of 212 patients (72±8 years, 111 men) with diabetes and mild-to-moderate AS who underwent echocardiographic follow-up and classified them into those who received favourable DPP-4 inhibitors (n=28, 13%), unfavourable DPP-4 inhibitors (n=69, 33%) and those who did not receive DPP-4 inhibitors (n=115, 54%).

RESULTS

Maximal transaortic velocity (Vmax) increased from 2.9±0.3 to 3.5±0.7 m/s during follow-up (median, 3.7 years), and the changes were not different between DPP-4 users as a whole and non-users (p=0.143). However, the favourable group showed significantly lower Vmax increase than the unfavourable or non-user group (p=0.018). Severe AS progression was less frequent in the favourable group (7.1%) than in the unfavourable (29.0%; p=0.03) or the non-user (29.6%; p=0.01) group. In Cox regression analysis after adjusting for age, baseline renal function and AS severity, the favourable group showed a significantly lower risk of severe AS progression (HR 0.116, 95% CI 0.024 to 0.551, p=0.007).

CONCLUSIONS

DPP-4 inhibitors with favourable pharmacokinetic and pharmacodynamic properties were associated with lower risk of AS progression. These results should be considered in the preparation of randomised clinical trials on the repositioning of DPP-4 inhibitors.

DPP-4 Inhibitors: Renoprotective Potential and Pharmacokinetics in Type 2 Diabetes Mellitus Patients with Renal Impairment

The continuously increasing incidence of diabetes worldwide has attracted the attention of the scientific community and driven the development of a novel class of antidiabetic drugs that can be safely and effectively used in diabetic patients. Of particular interest in this context are complications associated with diabetes, such as renal impairment, which is the main cause of high cardiovascular morbidity and mortality in diabetic patients. Intensive control of glucose levels and other risk factors associated with diabetes and metabolic syndrome provides the foundations for both preventing and treating diabetic nephropathy. Dipeptidyl peptidase-4 (DPP-4) inhibitors represent a highly promising novel class of oral agents used in the treatment of type 2 diabetes mellitus that may be successfully combined with currently available antidiabetic therapeutics in order to achieve blood glucose goals. Beyond glycemic control, emerging evidence suggests that DPP-4 inhibitors may have desirable off-target effects, including renoprotection. All type 2 diabetes mellitus patients with impaired renal function require dose adjustment of any DPP-4 inhibitor administered except for linagliptin, for which renal excretion is a minor elimination pathway. Thus, linagliptin is the drug most frequently chosen to treat type 2 diabetes mellitus patients with renal failure.

Pharmacology of dipeptidyl peptidase-4 inhibitors and its use in the management of metabolic syndrome: a comprehensive review on drug repositioning

OBJECTIVES

Despite advances in our understanding of metabolic syndrome (MetS) and the treatment of each of its components separately, currently there is no single therapy approved to manage it as a single condition. Since multi-drug treatment increases drug interactions, decreases patient compliance and increases health costs, it is important to introduce single therapies that improve all of the MetS components.

EVIDENCE ACQUISITION

We conducted a PubMed, Scopus, Google Scholar, Web of Science, US FDA, utdo.ir and clinicaltrial.gov search, gathered the most relevant preclinical and clinical studies that have been published since 2010, and discussed the beneficial effects of dipeptidyl peptidase (DPP)-4 inhibitors to prevent and treat different constituent of the MetS as a single therapy. Furthermore, the pharmacology of DPP-4 inhibitors, focusing on pharmacodynamics, pharmacokinetics, drug interactions and their side effects are also reviewed.

RESULTS

DPP-4 inhibitors or gliptins are a new class of oral anti-diabetic drugs that seem safe drugs with no severe side effects, commonly GI disturbance, infection and inflammatory bowel disease. They increase mass and function of pancreatic β-cells, and insulin sensitivity in liver, muscle and adipose tissue. It has been noted that gliptin therapy decreases dyslipidemia. DPP-4 inhibitors increase fatty oxidation, and cholesterol efflux, and decrease hepatic triglyceride synthase and de novo lipogenesis. They delay gastric emptying time and lead to satiety. Besides, gliptin therapy has anti-inflammatory and anti-atherogenic impacts, and improves endothelial function and reduces vascular stiffness.

CONCLUSION

The gathered data prove the efficacy of DPP-4 inhibitors in managing MetS in some levels beyond anti-diabetic effects. This review could be a lead for designing new DPP-4 inhibitors with greatest effects on MetS in future. Introducing drugs with polypharmacologic effects could increase the patient's compliance and decrease the health cost that there is not in multi-drug therapy. Graphical abstract ᅟ.

Absorption, metabolism, and excretion of [14C]evogliptin tartrate in male rats and dogs

The objective of this study was to determine the absorption, excretion, and metabolism of a novel, oral antihyperglycemic drug, evogliptin, in male rats and dogs. Plasma, urine, feces, and expired air samples were collected after a single oral dose administration of [¹⁴C]evogliptin, samples were analyzed by measuring overall radioactivity levels using high-performance liquid chromatography (HPLC), and radioactivity levels were measured by utilizing LC-tandem mass spectrometry (LC-MS/MS). The total amounts of radioactivity excreted in urine, feces, and expired air up to 168 h after administration of [¹⁴C]evogliptin tartrate to rats (30 mg evogliptin/kg) and dogs (10 mg evogliptin/kg) were 96.7% and 96.8% of initial doses administered, respectively. The extent of urinary and fecal excretion in the rat up to 168 h constituted 29.7% and 66.5% of the given dose, respectively; and in dog was 43.3% and 53.5%, respectively. A total of 23 possible metabolites were detected with radiochromatograms of plasma, urinary, and fecal samples, but only the structures of 12 metabolites were identified via LC-MS/MS analysis. Evogliptin was the major component. Regarding the total radiochromatographic peak areas, peaks 9 (evogliptin acid) and 11 (hydroxyevogliptin) were the major metabolites in rats, and peaks 8 [4(S)-hydroxyevogliptin glucuronide], 15 [4(S)-hydroxyevogliptin], and 17 [4(R)-hydroxyevogliptin] were the predominant metabolites in dogs. Data demonstrated that evogliptin was the major component excreted in urine and feces of rats and dogs, but the metabolite profiles varied between species.

[Metformin is a possible glucagon-like peptide 1 stimulator]

Metformin is an oral anti-hyperglycaemic drug used as first-line treatment of Type 2 diabetes. It is more effective when administered orally than when administered intravenously, and metformin formulations, which prolong the time residing in the gut are the most potent. This indicates that the intestine plays an essential role in metformin's mode of action. Metformin also increases plasma concentrations of the glucose-lowering gut incretin hormone glucagon-like peptide-1 (GLP-1). This metformin-induced GLP-1 increment may constitute an important link between the gut and the glucose-lowering effect of metformin.

[Novel antidiabetic drugs and cardiovascular complications]

This review summarizes the cardiovascular non-inferiority trials of novel antidiabetic drugs performed since 2008, when regulatory agencies started mandating thorough examination of their cardiovascular safety. So far, eight randomized trials on three different drug classes have been completed. Sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists may reduce cardiovascular risk and possibly mortality, while dipeptidyl dipeptidase-4 inhibitors may increase the risk of heart failure. A brief discussion of potential mechanisms and clinical implications is provided.

[Pharmacokinetics of Phosphate Retagliptin Tabletin in Patients with Renal Dysfunction]

OBJECTIVE

To compared the differences in pharmacokinetics of phosphate retagliptin tablets in patients with varying degrees of renal dysfunction.

METHODS

A total of 32 patients were categorized into five groups according to their renal function: normal,mild dysfunction, moderate dysfunction,severe dysfunction,and end stage renal dysfunction (ESRD). All of the patients took a single dose of 50 mg phosphate retagliptin tablet. Their plasma and urinary concentrations of phosphate retagliptin (SP2086) and phosphate retagliptin acid (SP2086 acid) were determined using LC-MS/MS methods. The plasma pharmacokinetic parameters were calculated using WinNolin 6.1 software.

RESULTS

Peak concentrations (C_max) of SP2086 reached at (1.07±0.35) h in the patients with mild renal dysfunction,(1.50±0.89) h in the patients with moderate renal dysfunction,(1.67±2.16) h in the patients with severe renal dysfunction,(2.42±2.15) h in the patients with ESRD,and (1.75±1.21) h in the normal participants,with a clearance (CL/F) of (23.50±6.01) ,(12.90±4.34) ,(6.70±1.55) ,(3.10±0.48) ,and (30.50±10.70) L/h,respectively. With the increasing damages in renal function presented an incease in C_max,time to reach C_max (_Tmax),and area under curve (AUC), a decrease in CL/F, of SP2086 and SP2086 acid. The 0-96 hurine cumulative excretion percentage (Ae%) of SP2086 ranged from 0.441% to 4.530%. The Ae% of SP2086 acid reached (71.7±14.3) % in the patients with mild renal dysfunction, (59.5±22.7) % in the patients with moderate renal dysfunction, (63.3±13.9) % in the patients with severe renal dysfunction, (34.1±20.0) % in the patient with ESRD,and (74.2±14.6) % in the normal participants, with a renal clearance (CL/R) of (220.0±51.2),(105.0±64.5),(54.5±7.6),(13.5±7.8),and (289.0±73.7) mL/min,respectively. Compared with the participants with normal renal function,the AUCs of SP2086 and SP2086 acid were 1.44 times and 2.32 times higher in the patients with moderate renal dysfunction,2.20 times and 4.39 times higher in the patients with severe renal dysfunction, and 2.83 times and 9.28 times higher in the patients with ESRD.

CONCLUSION

The dosage of phosphate retagliptin tablet is recommended at 100 mg/d for patients with normal renal function and those with mild renal dysfunction,at 50 mg/d for patients with moderate renal dysfunction,and at 25 mg/d for patients with severe renal dysfunction. No phosphate retagliptin tablet is recommended for patients with ESRD.

The pharmacokinetics and pharmacodynamics of alogliptin in children, adolescents, and adults with type 2 diabetes mellitus

Purpose

The aim of this study is to determine the pharmacokinetics (PK) and pharmacodynamics (PD) of a single 12.5- or 25-mg dose of alogliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, in pediatric (children and adolescents) and adult subjects with type 2 diabetes mellitus (T2DM).

Methods

A randomized, open-label, multicenter study was conducted in pediatric and adult subjects. Subjects in two pediatric groups (children and adolescents) were randomized 1:1 to receive a single oral dose of alogliptin 12.5 or 25 mg, respectively; all gender- and race-matched adult subjects received alogliptin 25 mg. Blood and urine samples were collected at prespecified time points for PK/PD analyses. A PK/PD model was developed using data from the study for steady-state simulations. Safety was also assessed.

Results

In pediatric subjects receiving the 25-mg dose, the mean alogliptin peak plasma concentrations (C_max) and AUC_0-inf values were 26 and 23% lower, respectively, than in adults receiving the 25-mg dose, but maximum observed DPP-4 inhibition effect (E_max) and AUEC_0–24 values were similar to those in adults. In pediatric subjects receiving the 12.5-mg dose, the mean alogliptin C_max and AUC_0-inf values were 58 and 54% lower, respectively, than those in adults, hence E_max and AUEC_0–24 values were also lower by 11 and 17%, respectively. The PK/PD model simulated data were consistent with study results. No safety concern was found.

Conclusions

A 25-mg dose of alogliptin in pediatric subjects achieved alogliptin exposures and DPP-4 inhibition similar to those in adult T2DM patients without safety concerns; therefore, this dose is recommended for a pediatric phase 3 trial.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-016-2175-1) contains supplementary material, which is available to authorized users.

Teneligliptin: a review in type 2 diabetes

Oral teneligliptin [Teneglucon® (Argentina)], a dipeptidyl peptidase-4 inhibitor, is indicated for the treatment of adults with type 2 diabetes (T2DM). This article reviews the pharmacology, therapeutic efficacy and tolerability of teneligliptin in the treatment of adults with T2DM. In 12- or 16-week, placebo-controlled phase 2 and 3 trials, oral teneligliptin 20 or 40 mg once daily, as monotherapy or in combination with metformin, glimepiride or pioglitazone improved glycaemic control, including in patients with end-stage renal disease, and was generally well tolerated. Most treatment-emergent adverse events were of mild intensity and relatively few patients discontinued treatment because of these events. Improvements in glycaemic control observed in short-term trials were maintained at 52 weeks in extension phases of these trials and in 52-week interventional studies, with no new safety concerns identified during this period. In the absence of direct head-to-head clinical trials, the position of teneligliptin relative to other antidiabetic agents in the management of T2DM remains to be determined. In the meantime, teneligliptin is a useful treatment option for adults with T2DM who have not responded adequately to diet and exercise regimens, or the addition of antidiabetic drugs.

Comparative review of dipeptidyl peptidase-4 inhibitors and sulphonylureas

Type 2 diabetes (T2DM) is a progressive disease, and pharmacotherapy with a single agent does not generally provide durable glycaemic control over the long term. Sulphonylurea (SU) drugs have a history stretching back over 60 years, and have traditionally been the mainstay choice as second-line agents to be added to metformin once glycaemic control with metformin monotherapy deteriorates; however, they are associated with undesirable side effects, including increased hypoglycaemia risk and weight gain. Dipeptidyl peptidase (DPP)-4 inhibitors are, by comparison, more recent, with the first compound being launched in 2006, but the class now globally encompasses at least 11 different compounds. DPP-4 inhibitors improve glycaemic control with similar efficacy to SUs, but do not usually provoke hypoglycaemia or weight gain, are relatively free from adverse side effects, and have recently been shown not to increase cardiovascular risk in large prospective safety trials. Because of these factors, DPP-4 inhibitors have become an established therapy for T2DM and are increasingly being positioned earlier in treatment algorithms. The present article reviews these two classes of oral antidiabetic drugs (DPP-4 inhibitors and SUs), highlighting differences and similarities between members of the same class, as well as discussing the potential advantages and disadvantages of the two drug classes. While both classes have their merits, the choice of which to use depends on the characteristics of each individual patient; however, for the majority of patients, DPP-4 inhibitors are now the preferred choice.

Overview of Data Concerning the Safe Use of Antihyperglycemic Medications in Type 2 Diabetes Mellitus and Chronic Kidney Disease

INTRODUCTION

It can be a challenge to manage glycemic control in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD), due to both patient and medication issues. Although most antihyperglycemic medications can be used in mild kidney disease, many medications are either not advised or require dose adjustments in more advanced CKD. This review summarizes product label information, pharmacokinetic and clinical studies, and clinical guidelines relevant to use of antihyperglycemic medications in CKD.

METHODS

Product labels and guidelines from North America and Europe, as well as pharmacokinetic and clinical studies of diabetes medication use in CKD were identified through Medline and PubMed searches, up to February 2015. Available data are summarized and correlations between treatment recommendations and available research are discussed, as are glycemic targets for patients with CKD.

RESULTS

Newer medications have significantly more data available than older medications regarding use in CKD, although larger clinical studies are still lacking for some drugs. As CKD advances, dose adjustment is needed for many medications [numerous dipeptidyl peptidase-4 inhibitors, some insulins, sodium glucose co-transporter 2 (SGLT2) inhibitors], although not for others (thiazolidinediones, meglitinides). Some medications are not recommended for use in more advanced CKD (metformin, SGLT2 inhibitors, some glucagon-like protein-1 receptor agonists) for safety or efficacy reasons. There is not always good alignment between label recommendations, pharmacokinetic or clinical studies, and guideline recommendations for use of these drugs in CKD. In particular, controversy remains about the use of metformin in moderate CKD and appropriate use of liraglutide and sulfonylureas in advanced CKD.

CONCLUSION

Considerable variability exists with respect to recommendations and clinical data for the many antihyperglycemic drugs used in patients with T2DM and CKD.

FUNDING

Eli Lilly and Company.

Pharmacological characterization of ZYDPLA1, a novel long-acting dipeptidyl peptidase-4 inhibitor

OBJECTIVE

Dipeptidyl peptidase-4 (DPP-4) is responsible for degradation of glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP), the endogenous incretins that stimulate glucose-dependent insulin secretion. The objective was to evaluate preclinical profile of a novel DPP-4 inhibitor ZYDPLA1.

METHODS

In vitro inhibition potency and selectivity were assessed using recombinant enzymes and/or plasma. In vivo efficacy was determined in oral glucose tolerance test or mixed meal tolerance test in C57BL/6J mice, db/db mice and Zucker fatty rats. Pharmacokinetics/pharmacodynamics was studied in mice, rats, dogs, and non-human primates.

RESULTS

ZYDPLA1 is a potent, competitive and long acting inhibitor of DPP-4 (Ki 0.0027 μM; Koff 2.3 × 10(-4 ) s(-1) ). ZYDPLA1 was more than 7000-fold selective for recombinant DPP-4 relative to DPP-8 and DPP-9, and more than 60 000-fold selective relative to fibroblast activation protein (FAP) in vitro. DPP-4 inhibition was comparable across species. In vivo, oral ZYDPLA1 elevated circulating GLP-1 and insulin levels in mice and rats and showed dose-dependent anti-hyperglycemic effect. Anti-hyperglycemic effect was also observed in db/db mice and Zucker fatty rats. ZYDPLA1 showed low clearance, large volume of distribution, and a long half-life with excellent oral bioavailability in all species. It significantly inhibited plasma DPP-4 activity in mice and rats for more than 48 h, and for up to 168 h in dogs and non-human primates. Allometric scaling predicted a half-life in humans of 53 to 166 h.

CONCLUSION

ZYDPLA1 is a potent, selective, long-acting oral DPP-4 inhibitor with potential to become once-a-week therapy for treatment of type 2 diabetes mellitus.

Determination of a novel dipeptidyl peptidase IV inhibitor in monkey plasma by HPLC-MS/MS and its application in a pharmacokinetics study

A lot of attention has been given to novel diabetes treatment, which is used to replace injectable insulin. A novel dipeptidyl peptidase IV inhibitor (HWH-10d) for treating type 2 diabetes was previously determined to have comparable efficacy to the marketed drug (alogliptin) in ICR male mice. Therefore, a sensitive and rapid liquid chromatography-tandem mass spectrometric method was developed and validated for the further evaluation of HWH-10d in monkey. The analytes were extracted through a liquid-liquid extraction with ethyl acetate. The linear detection range for HWH-10d in monkey plasma was from 0.5 to 2000 ng/mL with the lower limit of quantification of 0.5 ng/mL. The relative standard deviation was measured to be less than 10.4% for determination of inter- and intra-day precisions, and the relative error was determined to be within ±7.2% for all accuracy measurements. The simple and rapid LC-MS/MS method for HWH-10d in monkey plasma could be used for the pharmacokinetics studies of HWH-10d in monkeys. The oral bioavailability of HWH-10d in monkeys is 57.8%.

Pharmacokinetics in patients with chronic liver disease and hepatic safety of incretin-based therapies for the management of type 2 diabetes mellitus

Patients with type 2 diabetes mellitus have an increased risk of chronic liver disease (CLD) such as non-alcoholic fatty liver disease and steatohepatitis, and about one-third of cirrhotic patients have diabetes. However, the use of several antidiabetic agents, such as metformin and sulphonylureas, may be a concern in case of hepatic impairment (HI). New glucose-lowering agents targeting the incretin system are increasingly used for the management of type 2 diabetes. Incretin-based therapies comprise oral inhibitors of dipeptidyl peptidase-4 (DPP-4) (gliptins) or injectable glucagon-like peptide-1 (GLP-1) receptor agonists. This narrative review summarises the available data regarding the use of both incretin-based therapies in patients with HI. In contrast to old glucose-lowering agents, they were evaluated in specifically designed acute pharmacokinetic studies in patients with various degrees of HI and their hepatic safety was carefully analysed in large clinical trials. Only mild changes in pharmacokinetic characteristics of DPP-4 inhibitors were observed in patients with different degrees of HI, presumably without major clinical relevance. GLP-1 receptor agonists have a renal excretion rather than liver metabolism. Specific pharmacokinetic data in patients with HI are only available for liraglutide. No significant changes in liver enzymes were reported with DPP-4 inhibitors or GLP-1 receptor agonists, alone or in combination with various other glucose-lowering agents, in clinical trials up to 2 years in length. On the contrary, preliminary data suggested that incretin-based therapies may be beneficial in patients with CLD, more particularly in the presence of non-alcoholic fatty liver disease. Nevertheless, caution should be recommended, especially in patients with advanced cirrhosis, because of a lack of clinical experience with incretin-based therapies in these vulnerable patients.

Sitagliptin: a review of its use in patients with type 2 diabetes mellitus

Sitagliptin (Januvia(®), Xelevia™, Glactiv(®), Tesavel(®)) is an orally administered, potent and highly selective inhibitor of dipeptidyl peptidase-4 (DPP-4) and was the first agent of its class to be approved for use in the management of adults with type 2 diabetes. Numerous randomized placebo- or active comparator-controlled trials have demonstrated the efficacy of sitagliptin in terms of improving glycaemic control in patients with type 2 diabetes, including its use as monotherapy, initial combination therapy (usually with fixed-dose combinations of sitagliptin/metformin), or add-on therapy to metformin or to other antihyperglycaemic drugs, with or without metformin. The primary endpoint of the clinical trials was the reduction from baseline in glycosylated haemoglobin (HbA1c), although sitagliptin also showed beneficial effects for other endpoints, such as the proportion of patients who achieved target HbA1c, and reductions from baseline in fasting plasma glucose (FPG) levels and 2-h postprandial glucose (PPG) levels. Sitagliptin was generally well tolerated in clinical trials, had a low risk of hypoglycaemia (although this depends on background therapy) and had a neutral effect on body weight. Despite concerns regarding a possible increased risk of rare pancreatic adverse events (e.g. pancreatitis) with glucagon-like peptide-1 (GLP-1)-based therapies, such as GLP-1 receptor agonists and DPP-4 inhibitors, no causal association has been found; regulators in Europe recently conducted a review of available data, concluding that there is little evidence that these drugs could cause pancreatic inflammation or pancreatic cancer. A similar review is planned in the USA and postmarketing surveillance will continue. Thus, oral sitagliptin is an effective and generally well tolerated treatment option for the management of patients with type 2 diabetes.

Effect of renal impairment and haemodialysis on the pharmacokinetics of gemigliptin (LC15-0444)

This study evaluated the effects of renal impairment (RI) and haemodialysis (HD) on the pharmacokinetics of gemigliptin, a novel dipeptidyl peptidase-4 (DPP-4) inhibitor. After a 100 mg administration to subjects with normal renal function (n = 23) or RI (n = 24), plasma, urine or dialysate samples were analysed. Control subjects were matched to patients based on age, gender and body mass index. Patients with mild, moderate, severe RI and end-stage renal disease (ESRD) showed 1.20, 2.04, 1.50 and 1.66-fold (1.10, 1.49, 1.22 and 1.21-fold) increase of mean area under the time-plasma concentration curve from 0 to infinity (AUCinf) [maximum plasma concentration (Cmax)] of gemigliptin, respectively. Pharmacokinetics of gemigliptin was comparable between HD and non-HD periods in ESRD patients. Less than 4% of the dose was removed by 4 h HD. RI appeared to have modest effect on the gemigliptin disposition. No dose adjustment in patients with RI is proposed on the basis of exposure-response relationship. Impact of HD on the removal of gemigliptin was negligible.

Dipeptidyl peptidase-4 inhibitors: pharmacokinetics, efficacy, tolerability and safety in renal impairment

The dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of blood glucose-lowering therapy with proven efficacy, tolerability and safety. Four of the five commercially available DPP-4 inhibitors are subject to significant renal clearance, and pharmacokinetic studies in people with renal impairment have led to lower recommended doses based on creatinine clearance in order to prevent drug accumulation. Data from these pharmacokinetic studies and from supratherapeutic doses in healthy individuals and people with uncomplicated diabetes during development suggest, however, that there is a wide therapeutic margin. This should protect against toxicity if people with renal impairment are inadvertently prescribed higher doses than recommended. Doses appropriate to renal function are associated with reductions in HbA1c that are equivalent to those observed in people with type 2 diabetes who do not have renal impairment. Recent large-scale cardiovascular safety trials of saxagliptin and alogliptin have identified heart failure as a potential concern and renal impairment may increase the risk of this complication. Although the incidence of pancreatitis does not appear to be significantly increased by DPP-4 inhibitor therapy, renal impairment is also an independent risk factor. Additional data from other ongoing DPP-4 inhibitor cardiovascular safety trials should provide a more precise assessment of the risks of these uncommon complications, including in people with renal impairment.

Can genetics improve precision of therapy in diabetes?

Diabetes mellitus is a lifelong, incapacitating disease affecting multiple organs. Presently, type 2 diabetes (T2D) can neither be prevented nor cured and the disease is associated with devastating chronic complications. These complications impose an immense burden on the quality of life of patients and account for about 12% of direct health care costs in Europe. Genetic analysis will increase our understanding of this heterogeneous disease and may help offer more personalized treatment.

Pharmacokinetics, safety, and efficacy of DPP-4 inhibitors and GLP-1 receptor agonists in patients with type 2 diabetes mellitus and renal or hepatic impairment. A systematic review of the literature

Renal or hepatic impairment, often encountered in patients with type 2 diabetes, influences the pharmacokinetics and bioavailability of antihyperglycemic agents. An emerging concern is whether pharmacotherapy with incretin-based agents, the most recent drug classes to be introduced for type 2 diabetes, can be safely used in patients with renal insufficiency or hepatic damage. This literature review examines the results of studies on these novel drug classes, with a view to provide the practitioner with a balanced, evidence-based position when considering incretin-based therapies in patients with type 2 diabetes and impaired kidney or liver function. All currently available dipeptidyl peptidase-4 (DPP-4) inhibitors appear to be appropriate pharmacotherapeutic choices in patients with declining renal function, with linagliptin affording the added advantage of not requiring dose adjustment or periodic monitoring of drug-related kidney function. In contrast, caution is warranted with the use of glucagon-like peptide-1 (GLP-1) receptor agonists in patients with moderate or severe renal impairment. The slightly wider evidence base for liraglutide than for exenatide or lixisenatide is not sufficient to support its use in severe renal impairment. What little evidence there is for incretin-based therapies in hepatic impairment has come from a few past hoc analysis of clinical trials, with most precautions and warnings reflecting the paucity of knowledge about incretin efficacy or safety in this condition.

[Determination of yogliptin and its metabolite in Wistar rat plasma by liquid chromatography-tandem mass spectrometry]

A rapid, sensitive and simple liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the simultaneous determination of yogliptin and its metabolite in Wistar rat plasma. Linagliptin and dexamethasone were chosen as the internal standards of yogliptin and its metabolite, (R)-8-(3-hydroxypiperidine- -yl)-7-(but-2-yn-1-yl)-1-((5-fluorobenzo[d]thiazol-2-yl)methyl)-3-methyl- H-purine-2, 6 (3H, 7H)-dione, respectively. After a simple protein precipitation using acetonitrile as the precipitating solvent, both analytes and ISs were separated on a Grace Altima HP C18 column (2.1 mm x 50 mm, 5 microm) with gradient elution using methanol (containing 0.1% formic acid, 4 mmol x L(-1) ammonium acetate)-0.1% formic acid (containing 4 mmol x L(-1) ammonium acetate) as the mobile phase. A chromatographic total run time of 4.4 min was achieved. Mass spectrometric detection was conducted with electrospray ionization under positive-ion and multiple-reaction monitoring modes. Linear calibration curves for yogliptin and its metabolite were over the concentration range of 0.5 to 500 ng x mL(-1) with a lower limit of quantification of 0.5 ng x mL(-1). The intra- and inter- assay precisions were all below 14%, the accuracies were all in standard ranges. The method was used to determine the concentration of yogliptin and M1 in Wistar rat plasma after a single oral administration of yogliptin (27 mg x kg(-1)). The method was proved to be selective, sensitive and suitable for pharmacokinetic study of yogliptin and M1 in Wistar rat plasma.

[Alogliptin (Vipidia): a selective DPP-4 inhibitor with a good cardiovascular safety]

Alogliptin (Vipidia) is a new selective inhibitor of dipeptidyl peptidase-4. By potentiating insulin secretion and by inhibiting glucagon secretion, both in a glucose-dependent manner, it improves glucose control of type 2 diabetic patients, without increasing the risk of hypoglycaemia and inducing weight gain, with an excellent clinical and biological tolerance. Both efficacy and safety have been demonstrated in randomised controlled trials, in monotherapy or in combination with other oral antidiabetic agents or even insulin. These results were obtained independently of clinical or demographic patient characteristics, including in elderly subjects and in patients with renal insufficiency. However, because alogliptin is eliminated through the kidneys, the usual dose of 25 mg once daily should be reduced to 12.5 mg per day in case of moderate renal impairment and to 6.25 mg per day in case of severe renal failure. Cardiovascular safety of alogliptin has been demonstrated in a large prospective study (EXAMINE) showing non-inferiority versus placebo in type 2 diabetic patients following an acute coronary syndrome.

Pharmacokinetic and pharmacodynamic evaluation of linagliptin in African American patients with type 2 diabetes mellitus

AIM

This was an open label, multicentre phase I trial to study the pharmacokinetics and pharmacodynamics of the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin in African American patients with type 2 diabetes mellitus (T2DM).

METHODS

Forty-one African American patients with T2DM were included in this study. Patients were admitted to a study clinic and administered 5 mg linagliptin once daily for 7 days, followed by 7 days of outpatient evaluation.

RESULTS

Primary endpoints were area under the plasma concentration-time curve (AUC), maximum plasma concentration (Cmax ) and plasma DPP-4 trough inhibition at steady-state. Linagliptin geometric mean AUC was 194 nmol l(-1) h (geometric coefficient of variation, 26%), with a Cmax of 16.4 nmol l(-1) (41%). Urinary excretion was low (0.5% and 4.4% of the dose excreted over 24 h, days 1 and 7). The geometric mean DPP-4 inhibition at steady-state was 84.2% at trough and 91.9% at maximum. The exposure range and overall pharmacokinetic/pharmacodynamic profile of linagliptin in this study of African Americans with T2DM was comparable with that in other populations. Laboratory data, vital signs and physical examinations did not show any relevant findings. No safety concerns were identified.

CONCLUSIONS

The results of this study in African American patients with T2DM support the use of the standard 5 mg dose recommended in all populations.

The CTRB1/2 locus affects diabetes susceptibility and treatment via the incretin pathway

The incretin hormone glucagon-like peptide 1 (GLP-1) promotes glucose homeostasis and enhances β-cell function. GLP-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase-4 (DPP-4) inhibitors, which inhibit the physiological inactivation of endogenous GLP-1, are used for the treatment of type 2 diabetes. Using the Metabochip, we identified three novel genetic loci with large effects (30-40%) on GLP-1-stimulated insulin secretion during hyperglycemic clamps in nondiabetic Caucasian individuals (TMEM114; CHST3 and CTRB1/2; n = 232; all P ≤ 8.8 × 10(-7)). rs7202877 near CTRB1/2, a known diabetes risk locus, also associated with an absolute 0.51 ± 0.16% (5.6 ± 1.7 mmol/mol) lower A1C response to DPP-4 inhibitor treatment in G-allele carriers, but there was no effect on GLP-1 RA treatment in type 2 diabetic patients (n = 527). Furthermore, in pancreatic tissue, we show that rs7202877 acts as expression quantitative trait locus for CTRB1 and CTRB2, encoding chymotrypsinogen, and increases fecal chymotrypsin activity in healthy carriers. Chymotrypsin is one of the most abundant digestive enzymes in the gut where it cleaves food proteins into smaller peptide fragments. Our data identify chymotrypsin in the regulation of the incretin pathway, development of diabetes, and response to DPP-4 inhibitor treatment.

A randomized, open-label, crossover study to evaluate the pharmacokinetics of empagliflozin and linagliptin after coadministration in healthy male volunteers

BACKGROUND

Empagliflozin is an oral, potent, and selective inhibitor of sodium glucose cotransporter 2, inhibition of which reduces renal glucose reabsorption and results in increased urinary glucose excretion. Linagliptin is an oral inhibitor of dipeptidyl peptidase-4 approved for the treatment of type 2 diabetes in the United States, Europe, Japan, and Canada. Due to their complementary modes of action, there is a good rationale to combine empagliflozin with linagliptin to improve glycemic control in patients with type 2 diabetes.

OBJECTIVE

This study was conducted to investigate the pharmacokinetics of empagliflozin and linagliptin after coadministration in healthy volunteers.

METHODS

This was an open-label, randomized, multiple-dose, crossover study with 3 treatments in 2 treatment sequences. Sixteen healthy male subjects received treatment A (empagliflozin 50 mg once daily [QD] for 5 days), treatment B (empagliflozin 50 mg QD and linagliptin 5 mg QD for 7 days), and treatment C (linagliptin 5 mg QD for 7 days) in sequence AB then C, or sequence C then AB.

RESULTS

Sixteen healthy male subjects aged between 18 and 50 years with a body mass index of 18.5 to 29.9 kg/m(2) were included in the study. Linagliptin total exposure (AUC over a uniform dosing interval τ at steady state geometric mean ratio [GMR], 1.03 [90% CI, 0.96-1.11]) and peak exposure (C(max) at steady state GMR, 1.01 [90% CI, 0.87-1.19) exposure was unaffected by coadministration of empagliflozin. Empagliflozin total exposure (AUC over a uniform dosing interval τ at steady state GMR, 1.02 [90% CI, 0.97-1.07]) was unaffected by coadministration of linagliptin. There was a reduction in empagliflozin peak exposure (C(max) at steady state GMR, 0.88 [90% CI, 0.79-0.99]) when linagliptin was coadministered that was not considered clinically meaningful. No adverse events were reported during the coadministration period. No hypoglycemia was reported. Empagliflozin and linagliptin were well tolerated.

CONCLUSION

These data support the coadministration of empagliflozin and linagliptin without dose adjustments. European Union Drug Regulating Authorities Clinical Trials Registration: EudraCT 2008-006089-27.

Management of dyslipidemia and hyperglycemia with a fixed-dose combination of sitagliptin and simvastatin

The risk of death due to heart disease and stroke is up to four times higher in individuals with diabetes compared to individuals without diabetes. Most guidelines that address treatment of dyslipidemia in patients with diabetes consider diabetes a cardiovascular disease (CVD) "risk equivalent" and recommend intensive treatment of dyslipidemia for the purpose of CVD prevention. Statins (3-hydroxy 3-methylglutaryl coenzyme A reductase [HMG-CoA reductase] inhibitors) are first-line agents in achieving lipid goals as an adjunct to diet and exercise and should be used in most patients. In addition to lipid management and blood pressure control, glycemic control is a basic component in the management of diabetes. Glycemic control is achieved by combining diabetes self-management education, diet and exercise, and, where required, antihyperglycemic agents (OHAs). Persistence and adherence to therapy are critical in achieving recommended treatment goals. However, overall compliance with concomitantly prescribed OHAs and statins is low in patients with type 2 diabetes. Fixed-dose combination (FDC) therapies have been shown to improve adherence by reducing pill burden, the complexity of treatment regimen, and, potentially, cost. Based on the available evidence regarding the pharmacokinetics and the efficacy and safety profiles of each component drug, the sitagliptin/simvastatin FDC may provide a rational and well-tolerated approach to achieving better adherence to multiple-drug therapy and improved lipid lowering and glycemic control, with consequent reduction in cardiovascular risk, diabetic microvascular disease, and mortality in diabetic patients for whom treatment with both compounds is appropriate.

The effects of simvastatin on the pharmacokinectics of sitagliptin

BACKGROUND

Treatment with the combination of sitagliptin (a dipeptidyl peptidase 4 inhibitor which improves glycemic control) and simvastatin (a well characterized lipid-lowering agent) may be considered an appropriate approach to management of type 2 diabetes and its associated increased risk of cardiovascular disease.

OBJECTIVE

An investigation of the effects of simvastatin on the pharmacokinetics of sitagliptin was conducted.

METHODS

Ten healthy men and women were enrolled into an open-label, randomized, 2-period, crossover study. Pharmacokinetics of sitagliptin were measured after a single dose of sitagliptin 100-mg alone, and after a single dose of sitagliptin 100-mg administered on Day 5 of a 7 day course of simvastatin 80-mg once daily.

RESULTS

The geometric mean ratio of (sitagliptin + simvastatin) / sitagliptin and corresponding 90% confidence interval for sitagliptin AUC0-∞ and Cmax were 1.01 (0.97, 1.05), and 1.12 (1.00, 1.26), respectively.

CONCLUSIONS

Simvastatin has no clinically important effect on sitagliptin pharmacokinetics. No dose adjustment for either sitagliptin or simvastatin is recommended when these drugs are coadministered.

Long-acting peptidomimetics based DPP-IV inhibitors

Pyrrolidine based peptidomimetics are reported as potent and selective DPP-IV inhibitors for the treatment of T2DM. Compounds 16c and 16d showed excellent in vitro potency and selectivity towards DPP-IV and the lead compound 16c showed sustained antihyperglycemic effects, along with improved pharmacokinetic profile.

[Linagliptin (Trajenta): a selective DPP-4 inhibitor with limited renal elimination]

Linagliptin (Trajenta) is a selective inhibitor of dipeptidyl peptidase-4, an enzyme that degrades two incretin hormones, GLP-1 ("Glucagon-Like Peptide-1") and GIP ("Glucose-dependent Insulinotropic Polypeptide"). As other molecules belonging to this pharmacological class, linagliptin improves blood glucose control of type 2 diabetic patients, without increasing hypoglycaemic risk, without promoting weight gain and with a good clinical and biological tolerance profile. Both efficacy and safety have been demonstrated in randomized controlled trials as monotherapy or in combination with other glucose-lowering agents, independent of demographic or clinical patient's characteristics. The pharmacokinetics specificity of linagliptin comprises its biliary excretion, with low hepatic metabolism (no drug-drug interactions) and, in contrast to other gliptins, its negligible renal elimination. Because of these favourable properties, linagliptin may be used without dose adjustment (5 mg once a day) in patients with renal impairment, as well as in elderly people.

Effects of DPP-4 inhibitors on the heart in a rat model of uremic cardiomyopathy

Background

Uremic cardiomyopathy contributes substantially to mortality in chronic kidney disease (CKD) patients. Glucagon-like peptide-1 (GLP-1) may improve cardiac function, but is mainly degraded by dipeptidyl peptidase-4 (DPP-4).

Methodology/Principal Findings

In a rat model of chronic renal failure, 5/6-nephrectomized [5/6N] rats were treated orally with DPP-4 inhibitors (linagliptin, sitagliptin, alogliptin) or placebo once daily for 4 days from 8 weeks after surgery, to identify the most appropriate treatment for cardiac dysfunction associated with CKD. Linagliptin showed no significant change in blood level AUC(0-∞) in 5/6N rats, but sitagliptin and alogliptin had significantly higher AUC(0-∞) values; 41% and 28% (p = 0.0001 and p = 0.0324), respectively. No correlation of markers of renal tubular and glomerular function with AUC was observed for linagliptin, which required no dose adjustment in uremic rats. Linagliptin 7 µmol/kg caused a 2-fold increase in GLP-1 (AUC 201.0 ng/l*h) in 5/6N rats compared with sham-treated rats (AUC 108.6 ng/l*h) (p = 0.01). The mRNA levels of heart tissue fibrosis markers were all significantly increased in 5/6N vs control rats and reduced/normalized by linagliptin.

Conclusions/Significance

DPP-4 inhibition increases plasma GLP-1 levels, particularly in uremia, and reduces expression of cardiac mRNA levels of matrix proteins and B-type natriuretic peptides (BNP). Linagliptin may offer a unique approach for treating uremic cardiomyopathy in CKD patients, with no need for dose-adjustment.

Effect of renal impairment on the pharmacokinetics of the dipeptidyl peptidase-4 inhibitor linagliptin(*)

AIM

This study assessed the influence of various degrees of renal impairment on the exposure of linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor with a primarily non-renal route of excretion, in subjects with type 2 diabetes mellitus (T2DM).

METHODS

Linagliptin pharmacokinetics was studied under single-dose and steady-state conditions in subjects with mild, moderate and severe renal impairment (with and without T2DM) and end-stage renal disease and compared with the pharmacokinetics in subjects with normal renal function (with and without T2DM).

RESULTS

Renal excretion of unchanged linagliptin was <7% in all groups. Under single-dose conditions, the degree of renal impairment did not affect mean plasma linagliptin concentration-time profiles. These showed a similar decline and almost identical plasma concentrations 24 h postdosing in subjects with mild, moderate or severe renal impairment and in subjects with T2DM with and without renal impairment. Although there was a tendency towards slightly higher (20-60%) exposure in renally impaired subjects (with and without T2DM) compared with subjects with normal renal function, the steady-state AUC and C(max) values showed a large overlap and were not affected by the degree of renal impairment. The accumulation half-life of linagliptin ranged from 14-15 h in subjects with normal renal function to 18 h in severe renal impairment. Only a weak correlation (r(2) = 0.18) was seen between creatinine clearance and steady-state exposure.

CONCLUSIONS

Renal impairment has only a minor effect on linagliptin pharmacokinetics. Consequently, there will be no need for adjusting the linagliptin dose in renally impaired patients with T2DM.

The DPP-4 inhibitor linagliptin does not prolong the QT interval at therapeutic and supratherapeutic doses

AIM

To evaluate the potential effects of therapeutic and supratherapeutic doses of linagliptin (BI 1356) on the QT/QT(c) interval in healthy subjects.

METHODS

The study was a randomized, double-blind, placebo-controlled, four-period crossover study using single oral doses of linagliptin (5 mg and 100 mg), moxifloxacin (400 mg) and placebo. Electrocardiogram (ECG) profiles using triplicates of 12-lead 10-s ECGs were digitally recorded pre-dose and after drug administration. The mean change from baseline (MCfB) of the individually heart rate corrected QT interval (QT(c) I) between 1 and 4 h postdrug administration was the primary end point. Blood samples to measure plasma concentrations of linagliptin and its main metabolite were also obtained.

RESULTS

Forty-four Caucasian subjects (26 male) entered the study and 43 subjects completed the study as planned in the protocol. Linagliptin was not associated with an increase in the baseline-adjusted mean QT(c) I, at any time point. The placebo-corrected MCfB of QT(c) I was -1.1 (90% CI -2.7, 0.5) ms and -2.5 (-4.1, -0.9) ms for linagliptin 5 mg and 100 mg, respectively, thus within the non-inferiority margin of 10 ms according to ICH E14. Linagliptin was well tolerated; the assessment of ECGs and other safety parameters gave no clinically relevant findings at either dose tested. Maximum plasma concentrations after administration of 100-mg linagliptin were ∼24-fold higher than those observed previously for chronic treatment with the therapeutic 5-mg dose. Assay sensitivity was confirmed by a placebo-corrected MCfB of QT(c) I with moxifloxacin of 6.9 (90% CI 5.4, 8.5) ms.

CONCLUSIONS

Therapeutic and significantly supratherapeutic exposure to linagliptin is not associated with QT interval prolongation.

Thorough QT study of the effects of vildagliptin, a dipeptidyl peptidase IV inhibitor, on cardiac repolarization and conduction in healthy volunteers

OBJECTIVE

This randomized, double-blind study evaluated the effects of vildagliptin, a dipeptidyl peptidase IV inhibitor for treating type 2 diabetes, on cardiac repolarization and conduction.

METHODS

Healthy volunteers (n = 101) were randomized (1:1:1:1 ratio) to vildagliptin 100 or 400 mg, moxifloxacin 400 mg (active control), or placebo once daily for 5 days. Electrocardiograms were recorded at baseline and day 5 for 24 hours post-dose. Placebo-adjusted mean change from baseline in QT interval, heart-rate-corrected QT intervals by Fridericia's (QTcF) or Bazett's (QTcB) formula, and PR and QRS intervals were compared at each time-point (time-matched analysis) and for values averaged across the dosing period (time-averaged analysis).

RESULTS

For time-matched analysis, mean changes in QTcF with vildagliptin were below predefined limits for QTc prolongation (mean increase <5 ms; upper 90% confidence interval [CI] < 10 ms), except for vildagliptin 100 mg at 1 and 8 hours post-dose (upper 90% CI > 10 ms). With moxifloxacin, significant QTcF prolongation occurred at most time-points, demonstrating assay sensitivity. No vildagliptin- or placebo-treated volunteer had QTcF > 450 ms. Incidences of QTcF increases ≥30 ms with vildagliptin (100 and 400 mg) and placebo were similar (4-8%) and were much lower than with moxifloxacin (39%). No QTcF increase ≥60 ms was observed with vildagliptin or placebo (versus one with moxifloxacin). Time-averaged, time-matched, and categorical analyses of QT/QTcF/QTcB showed similar results. Drug exposure analysis showed no correlation between vildagliptin plasma levels and QTc changes. Vildagliptin had no effect on PR or QRS intervals. Although this study, completed before publication of current ICH E14 guidelines, was underpowered for time-matched analysis, the results are consistent with lack of effect of vildagliptin on QTc.

CONCLUSION

Vildagliptin did not prolong QT interval or affect cardiac conduction at the highest daily therapeutic dose or a fourfold higher dose.

Linagliptin: a novel dipeptidyl peptidase 4 inhibitor with a unique place in therapy

The dipeptidyl peptidase 4 (DPP-4) inhibitors comprise a promising new class of agent for the management of type 2 diabetes. They possess a range of physiological effects associated with improved glycemic control including stimulation of glucose-dependent insulin secretion and suppression of glucagon secretion, and lower blood glucose levels through different, but potentially complementary, mechanisms to standard oral therapies. Linagliptin is the latest DPP-4 inhibitor to complete pivotal phase 3 trials. The data show that linagliptin provides significant, clinically meaningful and sustained improvements in glycemic control, with an incidence of adverse events similar to placebo and an excellent tolerability profile. In addition, linagliptin has been shown to be weight neutral and, importantly, there was no increased risk of hypoglycemia attributed to linagliptin use in monotherapy or combination therapy with metformin or pioglitazone. A unique characteristic of linagliptin that differentiates it from other members of the class is its primarily nonrenal route of excretion. The linagliptin phase 3 program included several hundred patients with type 2 diabetes and different stages of renal disease and the data suggest that the drug would not need dose adjustment, regardless of the degree of renal impairment. There is a particular need for safe and effective therapeutic agents that can be used when renal function declines. Linagliptin has recently been approved by the US Food and Drug Administration and may find a place in therapy as a treatment option for the significant number of patients in whom metformin and the other DPP-4 inhibitors are either contraindicated or require dose adjustment because of moderate to severe renal impairment.

The oral DPP-4 inhibitor linagliptin significantly lowers HbA1c after 4 weeks of treatment in patients with type 2 diabetes mellitus

AIM

To investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of linagliptin in patients with type 2 diabetes mellitus (T2DM).

METHODS

After screening and a 14-day washout, subjects received linagliptin 2.5, 5 or 10 mg or placebo once-daily for 28 days in this randomized, double-blind, parallel, placebo-controlled within-dose groups study.

RESULTS

Seventy-seven patients entered the study (linagliptin: 61; placebo: 16). Four patients withdrew prematurely. There was little evidence of linagliptin accumulation. Exposure, maximum and trough plasma concentrations of linagliptin increased less than dose-proportionally. Rapid and sustained inhibition of dipeptidyl peptidase-4 reached 91-93% across linagliptin doses at steady state. At the end of the 24-h dosing interval, inhibition was still high (82-90%). There were marked increases in plasma glucagon-like peptide-1 after 28 days of dosing. Compared to placebo, all linagliptin doses resulted in statistically significant decreases of the area under the glucose curve following a meal tolerance test on day 29, that is, 24 h after the last study drug intake. After 28 days of treatment with linagliptin the placebo-corrected mean change in haemoglobin A1c (HbA1c) (median baseline 7.0%) was -0.31% (2.5-mg dose), -0.37% (5-mg dose) and -0.28% (10-mg dose). The frequency of adverse events was similar for linagliptin (31%) and placebo (34%). There were no notable safety concerns.

CONCLUSIONS

Linagliptin administration led to attenuation of postprandial glucose excursions and, despite a low HbA1c at baseline, statistically significant reductions in HbA1c after only 4 weeks of treatment. Linagliptin had a safety and tolerability profile similar to placebo in T2DM patients.

DPP IV inhibitors: successes, failures and future prospects

The dipeptidyl peptidase IV (DPP IV) enzyme is a novel target for the treatment of type 2 diabetes. Several DPP IV inhibitors are in the clinical development, since they are safe and tolerable with no increased risk of adverse events compared to placebo and have a low risk of hypoglycemia. They are flourishing as monotherapy and also in combination with commonly prescribed antidiabetic agents and are appropriate for once-daily oral dosing. However, further studies are needed to validate both long-term β-cell preservation and the role of these agents in the management of diabetes. The present review gives an inside out of the DPP IV inhibitors for its success, failure and future prospects in the treatment of diabetes and associated complication.

Evaluation of the potential for pharmacokinetic and pharmacodynamic interactions between dutogliptin, a novel DPP4 inhibitor, and metformin, in type 2 diabetic patients

OBJECTIVE

Dutogliptin is a novel, orally available, potent, and selective DPP4 inhibitor that improves glycemic control in type 2 diabetic patients. The objective of this study was to evaluate the potential pharmacokinetic and pharmacodynamic interactions, as well as the tolerability, of dutogliptin and metformin alone and in combination in type 2 diabetic patients.

METHODS

This was a single-center, randomized, open-label, 3-way, crossover study in type 2 diabetic patients. All patients received three treatment regimens, each of 5 days duration in order to reach steady state: 400 mg once daily of dutogliptin (the anticipated clinical dose); 1000 mg metformin twice daily (maximum effective clinical dose); and concomitant administration of 400 mg dutogliptin once daily and 1000 mg metformin twice daily.

RESULTS

Co-administration of dutogliptin and metformin did not alter the pharmacokinetics of either agent. The geometric mean ratio, GMR (dutogliptin + metformin/dutogliptin) of the area under the plasma concentration-time curve (AUC(0-24h)) at steady state was 0.91 (90% CI: 0.79-1.06; p = 0.29); the GMR of the maximum plasma concentrations (C(max)) was 0.95 (90% CI: 0.76-1.19; p = 0.70); the time to maximum plasma concentrations (T(max)) was essentially the same for dutogliptin with or without metformin. The GMR (dutogliptin + metformin/metformin) of AUC(0-12h) at steady state was 0.99 (90% CI: 0.84-1.17; p = 0.93); the GMR of C(max) was 0.91 (90% CI: 0.79-1.04; p = 0.18); T(max) was comparable for metformin with or without dutogliptin. Metformin added to dutogliptin had no effect on plasma DPP4 inhibition. All three treatment regimens were well tolerated.

CONCLUSIONS

In this small, multiple dose study, the steady state pharmacokinetics of either dutogliptin or metformin were not altered by co-administration of the two agents. Dutogliptin and metformin were well tolerated either alone or in combination and co-administered metformin did not alter the ex vivo DPP4 inhibition by dutogliptin. There is no need to consider pharmacokinetic and pharmacodynamic interactions when determining the dosage of either agent for co-administration. A phase 3 clinical trial is underway to provide more definitive data on the safety and efficacy of dutogliptin administered on a background of metformin treatment.

Pharmacokinetics of dipeptidylpeptidase-4 inhibitors

Type 2 diabetes (T2DM) is a complex disease combining defects in insulin secretion and insulin action. New compounds have been developed for improving glucose-induced insulin secretion and glucose control, without inducing hypoglycaemia or weight gain. Dipeptidylpeptidase-4 (DPP-4) inhibitors are new oral glucose-lowering agents, so-called incretin enhancers, which may be used as monotherapy or in combination with other antidiabetic compounds. Sitagliptin, vildaglipin and saxagliptin are already on the market in many countries, either as single agents or in fixed-dose combined formulations with metformin. Other DPP-4 inhibitors, such as alogliptin and linagliptin, are currently in late phase of development. The present paper summarizes and compares the main pharmacokinetics (PK) properties, that is, absorption, distribution, metabolism and elimination, of these five DPP-4 inhibitors. Available data were obtained in clinical trials performed in healthy young male subjects, patients with T2DM, and patients with either renal insufficiency or hepatic impairment. PK characteristics were generally similar in young healthy subjects and in middle-aged overweight patients with diabetes. All together gliptins have a good oral bioavailability which is not significantly influenced by food intake. PK/pharmacodynamics characteristics, that is, sufficiently prolonged half-life and sustained DPP-4 enzyme inactivation, generally allow one single oral administration per day for the management of T2DM; the only exception is vildagliptin for which a twice-daily administration is recommended because of a shorter half-life. DPP-4 inhibitors are in general not substrates for cytochrome P450 (except saxagliptin that is metabolized via CYP 3A4/A5) and do not act as inducers or inhibitors of this system. Several metabolites have been documented but most of them are inactive; however, the main metabolite of saxagliptin also exerts a significant DPP-4 inhibition and is half as potent as the parent compound. Renal excretion is the most important elimination pathway, except for linagliptin whose metabolism in the liver appears to be predominant. PK properties of gliptins, combined with their good safety profile, explain why no dose adjustment is necessary in elderly patients or in patients with mild to moderate hepatic impairment. As far as patients with renal impairment are concerned, significant increases in drug exposure for sitagliptin and saxagliptin have been reported so that appropriate reductions in daily dosages are recommended according to estimated glomerular filtration rate. The PK characteristics of DPP-4 inhibitors suggest that these compounds are not exposed to a high risk of drug-drug interactions. However, the daily dose of saxagliptin should be reduced when coadministered with potent CYP 3A4 inhibitors. In conclusion, besides their pharmacodynamic properties leading to effective glucose-lowering effect without inducing hypoglycaemia or weight gain, DPP-4 inhibitors show favourable PK properties, which contribute to a good efficacy/safety ratio for the management of T2DM in clinical practice.