Gemigliptin: An Update of Its Clinical Use in the Management of Type 2 Diabetes Mellitus

Gemigliptin, a potent selective dipeptidyl peptidase 4 inhibitor, protects endothelial progenitor cells by oxidative stress via caspase-3 dependent pathway

Endothelial progenitor cells (EPCs) are exclusive players in vasculogenesis and endothelial regeneration. EPCs are of two types and their differentiation is mediated by different growth factors. A decrease in EPC number and function causes cardiovascular abnormalities and reduced angiogenesis. Various studies has documented a role of EPCs in diabetes. EPCs treatment with different drugs improve insulin secretion but causes other abnormalities. In vivo and in vitro studies have reported anti glycation effect of gemigliptin but no data is available on in vitro effect of gemigliptin on EPC number and functional credibility. The current study was aimed to find an in vitro effect of gemigliptin on EPC number and function along with an effective treatment dose of gemigliptin. EPCs were isolated, cultured and phenotypically characterized using Dil- AcLDL and ulex-lectin fluorescence staining. EPCs were then treated with different doses of Zemiglo and their viability analyzed with viability assay using water-soluble tetrazolium salt (WST-1), by Annexin V and Propidium Iodide (PI) staining, senescence-associated beta-galactosidase (SA-β-gal) staining, western blot and Flow cytometric analysis of apoptotic signals. The results demonstrated that the isolated EPCs has typical endothelial phenotypes. And these EPCs were of two types based on morphology i.e., early and late EPCs. Gemigliptin dose dependently improved the EPCs morphology and increased EPCs viability, the most effective dose being the 20 μM. Gemigliptin at 10 μM, 20 μM and 50 μM significantly increased the BCL-2 levels and at 20 μM significantly decreased the Caspase-3 levels in EPCs. In conclusion, gemigliptin dose dependently effects the EPCs viability and morphology through Caspase-3 signaling. Our results are the first report of gemigliptin effect on EPC viability and morphology.

Synthesis and clinical application of representative small-molecule dipeptidyl Peptidase-4 (DPP-4) inhibitors for the treatment of type 2 diabetes mellitus (T2DM)

Diabetes mellitus is a chronic metabolic disorder characterized by high blood glucose levels, which can cause many diseases, including osteoporosis, fractures, arthritis, and foot complications. The inhibitors of dipeptidyl peptidase-4 (DPP-4), an enzyme involved in glucose metabolism regulation, are essential for managing Type 2 Diabetes Mellitus (T2DM). The inhibition of DPP-4 has become a promising treatment approach for T2DM because it can increase levels of active glucagon-like peptide-1 (GLP-1), leading to improved insulin secretion in response to glucose and reduced release of glucagon. The review commences by elucidating the role of DPP-4 in glucose homeostasis and its significance in T2DM pathophysiology. Furthermore, it presents the mechanism of action, preclinical pharmacodynamics, clinical efficacy, and toxicity profiles of small-molecule DPP-4 inhibitors across various clinical stages. This comprehensive review provides valuable insights into the synthesis and clinical application of DPP-4 inhibitors, serving as an invaluable resource for researchers, clinicians, and pharmaceutical professionals interested in diabetes therapeutics and drug development.

Selective targeting of dipeptidyl-peptidase 4 (DPP-4) positive senescent chondrocyte ameliorates osteoarthritis progression

Senescent cells increase in many tissues with age and induce age-related pathologies, including osteoarthritis (OA). Senescent chondrocytes (SnCs) are found in OA cartilage, and the clearance of those chondrocytes prevents OA progression. However, targeting SnCs is challenging due to the absence of a senescent chondrocyte-specific marker. Therefore, we used flow cytometry to screen and select senescent chondrocyte surface markers and cross-validated with published transcriptomic data. Chondrocytes expressing dipeptidyl peptidase-4 (DPP-4), the selected senescent chondrocyte-specific marker, had multiple senescence phenotypes, such as increased senescence-associated-galactosidase, p16, p21, and senescence-associated secretory phenotype expression, and showed OA chondrocyte phenotypes. To examine the effects of DPP-4 inhibition on DPP-4+ SnCs, sitagliptin, a DPP-4 inhibitor, was treated in vitro. As a result, DPP-4 inhibition selectively eliminates DPP-4+ SnCs without affecting DPP-4- chondrocytes. To assess in vivo therapeutic efficacy of targeting DPP-4+ SnCs, three known senolytics (ABT263, 17DMAG, and metformin) and sitagliptin were comparatively verified in a DMM-induced rat OA model. Sitagliptin treatment specifically and effectively eliminated DPP-4+ SnCs, compared to the other three senolytics. Furthermore, Intra-articular sitagliptin injection to the rat OA model increased collagen type II and proteoglycan expression and physical functions and decreased cartilage destruction, subchondral bone plate thickness and MMP13 expression, leading to the amelioration of OA phenotypes. Collectively, OARSI score was lowest in the sitagliptin treatment group. Taken together, we verified DPP-4 as a surface marker for SnCs and suggested that the selective targeting of DPP-4+ chondrocytes could be a promising strategy to prevent OA progression.

A Multicenter, Randomized, Open-Label Study to Compare the Effects of Gemigliptin Add-on or Escalation of Metformin Dose on Glycemic Control and Safety in Patients with Inadequately Controlled Type 2 Diabetes Mellitus Treated with Metformin and SGLT-2 Inhibitors (SO GOOD Study)

Background

We aimed to compare efficacy and safety between gemigliptin add-on and escalation of the metformin dose in patients with inadequately controlled type 2 diabetes mellitus (T2DM) despite treatment with metformin and SGLT2 inhibitors.

Methods

This study was a multicenter, randomized, open-label, active-controlled, parallel-group comparative study. Patients with T2DM uncontrolled on metformin and SGLT2 inhibitors were randomized to receive gemigliptin 50 mg as an add-on (GEM group, n = 37) or escalation of the metformin dose (500 mg, MET group, n = 38) for 24 weeks. The primary endpoint was the change in glycosylated hemoglobin (HbA1c) from baseline to week 24.

Results

At weeks 12 and 24, the reduction in HbA1c levels was significantly greater in the GEM group than in the MET group (GEM vs. MET = -0.64% ± 0.34% vs. -0.36% ± 0.50%, p = 0.009 at week 12; -0.61% ± 0.35% vs. -0.33% ± 0.70%, p = 0.045 at week 24). The proportions of patients who achieved target HbA1c levels of <7.0% at weeks 12 and 24 and <6.5% at week 12 were greater in the GEM group than in the MET group. An index of β-cell function was also significantly improved in the GEM group. The safety profiles were similar between the two groups.

Conclusions

Gemigliptin add-on therapy may be more effective than metformin dose escalation in patients with T2DM insufficiently controlled using metformin and SGLT2 inhibitors, without safety concerns. This trial is registered with CRIS_number: KCT0003520.

The effect of gemigliptin treatment on immune parameters including regulatory T cells in patients with type 2 diabetes and moderate to very severe chronic renal impairment

It is crucial to understand the impact of DPP-4 inhibitors on the immune system, particularly T cell differentiation, maturation, and proliferation, in patients with type 2 diabetes and CKD. This prospective observational study aimed to investigate the distribution of immune cells (particularly regulatory T cells), following the administration of gemigliptin, a DPP-4 inhibitor, in patients with type 2 diabetes mellitus and chronic kidney disease. We enrolled 28 patients with type 2 diabetes, aged 20 to 69, who had been taking a daily dose of 50mg gemigliptin for <3 months and had chronic kidney disease stages 3, 4, or 5, including that undergoing dialysis. T regulatory cells were defined as CD4 + CD25 high CD127 low/- FoxP3 + phenotype, and flow cytometry was used to examine the distribution of T regulatory cells. In the patient group, blood samples were collected at baseline, as well as at 3 and 6 months after initiating medication. Of the 28 patients, 17 (60.7%) were male and the mean age was 61.82 ± 8.03 years. Serum Cr ≥ 1.5 mg/dL was 16 (57%), and Cr < 1.5 mg/dL was 12 (43%). The number of CD4(+)/CD25(+) cells did not significantly increase or decrease in baseline, 3 months, and 6 months time changes, and the number of CD127(-/FoxP3(+) cells did not change significantly. Treatment with gemigliptin for 3 and 6 months did not significantly alter the number, percentage, or ratio of circulating Treg cells in patients with type 2 diabetes and CKD. Therefore, the administration of gemigliptin may help maintain regulatory T cells or have no significant impact.

Pharmacokinetic and pharmacodynamic interaction of DWP16001, a sodium-glucose cotransporter 2 inhibitor, with gemigliptin and metformin in healthy adults

AIMS

DWP16001, a novel sodium-glucose cotransporter 2 inhibitor, is under clinical development for the treatment of type 2 diabetes mellitus. This study aimed to explore the pharmacokinetics (PK) and pharmacodynamics interaction of DWP16001 with gemigliptin and metformin.

METHODS

A randomized, open-label, 2-sequence, 2-period crossover study was conducted in 34 healthy male subjects. All subjects received a single oral dose of DWP16001 2 mg with and without gemigliptin and metformin (8 days of 50 mg once-daily dose and 1000 mg twice daily dose for gemigliptin and metformin, respectively). Serial blood samples were collected for PK and serum glucose analysis, and timed urine samples were collected to analyse urine glucose excretion (UGE). The PK and pharmacodynamic parameters were analysed by the noncompartmental method.

RESULTS

The PK interactions of DWP16001, gemigliptin and metformin were not clinically significant. The geometric mean ratios (with 90% confidence intervals) of coadministration to separate administration for area under the time-concentration curves were 1.04 (1.02-1.06), 1.03 (0.98-1.09) and 1.17 (1.12-1.22), for gemigliptin, metformin and DWP16001 respectively. The UGE induced by DWP16001 was not affected by the coadministration of gemigliptin and metformin.

CONCLUSION

The results suggest that the DWP16001 could be added to metformin and gemigliptin combination therapy without dose adjustment.

DPP-4 inhibitors for treating T2DM - hype or hope? an analysis based on the current literature

DPP-4 inhibition is an interesting line of therapy for treating Type 2 Diabetes Mellitus (T2DM) and is based on promoting the incretin effect. Here, the authors have presented a brief appraisal of DPP-4 inhibitors, their modes of action, and the clinical efficiency of currently available drugs based on DPP-4 inhibitors. The safety profiles as well as future directions including their potential application in improving COVID-19 patient outcomes have also been discussed in detail. This review also highlights the existing queries and evidence gaps in DPP-4 inhibitor research. Authors have concluded that the excitement surrounding DPP-4 inhibitors is justified because in addition to controlling blood glucose level, they are good at managing risk factors associated with diabetes.

Therapeutic Effects of Switching to Anagliptin from Other DPP-4 Inhibitors in T2DM Patients with Inadequate Glycemic Control: A Non-interventional, Single-Arm, Open-Label, Multicenter Observational Study

INTRODUCTION

The effects of switching DPP-4 inhibitors in type 2 diabetes mellitus (T2DM) patients are being widely studied. However, information of which factors affect the therapeutic response is limited. We evaluated the difference in HbA1c lowering effect by comorbidity and other variables after switching to anagliptin in patients with T2DM inadequately controlled by other DPP-4 inhibitors.

METHODS

In a multicenter, open-label, single-arm, prospective observational study, patients with T2DM, HbA1c ≥ 7.0% who have taken DPP-4 inhibitors other than anagliptin, either alone or in combination (DPP-4 inhibitors + metformin/sulfonylurea (SU)/thiazolidinedione (TZD)/insulin), for at least 8 weeks were enrolled. After the switch to anagliptin, HbA1c and available clinical characteristics were determined.

RESULTS

The change in HbA1c levels from baseline to week 12 and 24 was - 0.40% and - 0.42% in all patients. However, comparing the subgroups without and with comorbidities, the change in HbA1c levels at weeks 12 and 24 was - 0.68% and - 0.89% vs. - 0.27% and 0.22%, respectively. In addition, the proportion of patients achieving HbA1c < 7% from baseline to week 12 and 24 was increased to 70% and 70% vs. 20% and 24%, respectively. Duration of T2DM and different subtype classes of DPP-4 inhibitor did not significantly contribute to the change in HbA1c.

CONCLUSION

In patients with T2DM poorly controlled by other DPP-4 inhibitors, HbA1c levels were significantly decreased after switching to anagliptin. Given that the change in HbA1c was greater in patients without comorbidities than in patients with comorbidities, switching to anagliptin before adding other oral hypoglycemic agents (OHAs) may be an option in patients without comorbidities.

Glucagon-like peptide-1 (GLP-1) receptor agonists and neuroinflammation: Implications for neurodegenerative disease treatment

Chronic, excessive neuroinflammation is a key feature of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). However, neuroinflammatory pathways have yet to be effectively targeted in clinical treatments for such diseases. Interestingly, increased inflammation and neurodegenerative disease risk have been associated with type 2 diabetes mellitus (T2DM) and insulin resistance (IR), suggesting that treatments that mitigate T2DM pathology may be successful in treating neuroinflammatory and neurodegenerative pathology as well. Glucagon-like peptide-1 (GLP-1) is an incretin hormone that promotes healthy insulin signaling, regulates blood sugar levels, and suppresses appetite. Consequently, numerous GLP-1 receptor (GLP-1R) stimulating drugs have been developed and approved by the US Food and Drug Administration (FDA) and related global regulatory authorities for the treatment of T2DM. Furthermore, GLP-1R stimulating drugs have been associated with anti-inflammatory, neurotrophic, and neuroprotective properties in neurodegenerative disorder preclinical models, and hence hold promise for repurposing as a treatment for neurodegenerative diseases. In this review, we discuss incretin signaling, neuroinflammatory pathways, and the intersections between neuroinflammation, brain IR, and neurodegenerative diseases, with a focus on AD and PD. We additionally overview current FDA-approved incretin receptor stimulating drugs and agents in development, including unimolecular single, dual, and triple receptor agonists, and highlight those in clinical trials for neurodegenerative disease treatment. We propose that repurposing already-approved GLP-1R agonists for the treatment of neurodegenerative diseases may be a safe, efficacious, and cost-effective strategy for ameliorating AD and PD pathology by quelling neuroinflammation.

FDA-Approved Trifluoromethyl Group-Containing Drugs: A Review of 20 Years

As people around the world regard 2020 as the year of COVID-19, the medical community considers this year to be the second-best year, shared with the year 1996, with respect to the number of drug molecules approved by the US Food and Drug Administration (FDA). Both years, 2020 and 1996, had a record of 53 new drug molecules approved by the FDA. In the year 2020, 53 new chemical entities and 13 biological medicines were approved, including 10 monoclonal antibodies, 2 antibody-drug conjugates, 3 peptides, and 2 oligonucleotides. Among them, most of the compounds were found to have fluorine or fluorine-containing functional groups exhibiting numerous pharmacological activities. Herein, we summarized the trifluoromethyl (TFM, -CF3)-group-containing FDA-approved drugs for the last 20 years. This article specially features and details the previous 20-year literature data, covering CF3-incorporated potential drug molecules, including their syntheses and uses for various diseases and disorders. The review covers the detailed chemistry of 19 FDA-approved drugs in the past 20 years, which contains the TFM group as one of the pharmacophores.

Divergent Reaction of Activated Pyridines with α,α-Difluorinated gem-Diols: Regioselective Synthesis of gem-Difluorinated Dihydropyridines and Dihydropyridones

The nucleophilic reactivity of α,α-difluorinated gem-diols toward activated pyridinium salts has been capitalized in a highly regioselective fashion, offering biologically relevant 1,4-dihydropyridines and 3,4-dihydro-2-pyridones adorned with the valuable gem-difluoromethylene motif. The protocol is scalable as well as high yielding and accommodates a broad range of substrates and functional groups. Additionally, the synthesis of difluorinated oxa-azabicyclo[3.3.1]nonane frameworks has been showcased through product diversification.

Does DPP-IV Inhibition Offer New Avenues for Therapeutic Intervention in Malignant Disease?

Simple Summary

There is growing interest in identifying the effects of antidiabetic agents on cancer risk, progression, and anti-cancer treatment due to the long-term use of these medications and the inherently increased risk of malignancies in diabetic patients. Tumor development and progression are affected by multiple mediators in the tumor microenvironment, several of which may be proteolytically modified by the multifunctional protease dipeptidyl peptidase-IV (DPP-IV, CD26). Currently, low-molecular-weight DPP-IV inhibitors (gliptins) are used in patients with type 2 diabetes based on the observation that DPP-IV inhibition enhances insulin secretion by increasing the bioavailability of incretins. However, the DPP-IV-mediated cleavage of other biopeptides and chemokines is also prevented by gliptins. The potential utility of gliptins in other areas of medicine, including cancer, is therefore being evaluated. Here, we critically review the existing evidence on the role of DPP-IV inhibitors in cancer pathogenesis, their potential to be used in anti-cancer treatment, and the possible perils associated with this approach.

Abstract

Dipeptidyl peptidase IV (DPP-IV, CD26) is frequently dysregulated in cancer and plays an important role in regulating multiple bioactive peptides with the potential to influence cancer progression and the recruitment of immune cells. Therefore, it represents a potential contributing factor to cancer pathogenesis and an attractive therapeutic target. Specific DPP-IV inhibitors (gliptins) are currently used in patients with type 2 diabetes mellitus to promote insulin secretion by prolonging the activity of the incretins glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Nevertheless, the modulation of the bioavailability and function of other DPP-IV substrates, including chemokines, raises the possibility that the use of these orally administered drugs with favorable side-effect profiles might be extended beyond the treatment of hyperglycemia. In this review, we critically examine the possible utilization of DPP-IV inhibition in cancer prevention and various aspects of cancer treatment and discuss the potential perils associated with the inhibition of DPP-IV in cancer. The current literature is summarized regarding the possible chemopreventive and cytotoxic effects of gliptins and their potential utility in modulating the anti-tumor immune response, enhancing hematopoietic stem cell transplantation, preventing acute graft-versus-host disease, and alleviating the side-effects of conventional anti-tumor treatments.

Increasing Age Associated with Higher Dipeptidyl Peptidase-4 Inhibition Rate Is a Predictive Factor for Efficacy of Dipeptidyl Peptidase-4 Inhibitors

BACKGROUND

It is not known which type 2 diabetes mellitus (T2DM) patients would most benefit from dipeptidyl peptidase-4 (DPP-4) inhibitor treatment. We aimed to investigate the predictors of response to DPP-4 inhibitors considering degree of DPP-4 inhibition.

METHODS

This study is a post hoc analysis of a 24-week, randomized, double-blind, phase III trial that compared the efficacy and safety of a DPP-4 inhibitor (gemigliptin vs. sitagliptin) in patients with T2DM. Subjects were classified into tertiles of T1 <65.26%, T2=65.26%-76.35%, and T3 ≥76.35% by DPP-4 inhibition. We analyzed the change from baseline in glycosylated hemoglobin (HbA1c) according to DPP-4 inhibition with multiple linear regression adjusting for age, ethnicity, body mass index, baseline HbA1c, and DPP-4 activity at baseline.

RESULTS

The mean age was greater in the high tertile group compared with the low tertile group (T1: 49.8±8.3 vs. T2: 53.1±10.5 vs. T3: 55.3±9.5, P<0.001) of DPP-4 inhibition. Although HbA1c at baseline was not different among tertiles of DPP-4 inhibition (P=0.398), HbA1c after 24-week treatment was lower in the higher tertile compares to the lower tertile (T1: 7.30%±0.88% vs. T2: 7.12%±0.78% vs. T3: 7.00%±0.78%, P=0.021). In multiple regression analysis, DPP-4 enzyme inhibition rate was not a significant determent for HbA1c reduction due to age. In subgroup analysis by tertile of DPP-4 inhibition, age was the only significant predictor and only in the highest tertile (R2=0.281, B=-0.014, P=0.024).

CONCLUSION

This study showed that HbA1c reduction by DPP-4 inhibitor was associated with increasing age, and this association was linked with higher DPP-4 inhibition.

Pleiotropic Benefits of DPP-4 Inhibitors Beyond Glycemic Control

Dipeptidyl peptidase (DPP)-4 inhibitors are oral anti-diabetic medications that block the activity of the ubiquitous enzyme DPP-4. Inhibition of this enzyme increases the level of circulating active glucagon-like peptide (GLP)-1 secreted from L-cells in the small intestine. GLP-1 increases the glucose level, dependent on insulin secretion from pancreatic β-cells; it also decreases the abnormally increased level of glucagon, eventually decreasing the blood glucose level in patients with type 2 diabetes. DPP-4 is involved in many physiological processes other than the degradation of GLP-1. Therefore, the inhibition of DPP-4 may have numerous effects beyond glucose control. In this article, we review the pleiotropic effects of DPP-4 inhibitors beyond glucose control, including their strong beneficial effects on the stress induced accelerated senescence of vascular cells, and the possible clinical implications of these effects.

Antidiabetic effect of gemigliptin: a systematic review and meta-analysis of randomized controlled trials with Bayesian inference through a quality management system

Gemigliptin is one of the latest dipeptidyl peptidase-4 inhibitors developed by LG Life Sciences. Since the early 2000s, several randomized controlled trials (RCTs) of gemigliptin have been conducted. However, no study has directly compared its antidiabetic effects through a systematic review and meta-analysis. Therefore, in this study, we performed a systematic review and meta-analysis on RCTs. In particular, a subsequent meta-analysis was performed using Bayesian inference, and an updated quality management system model was integrated throughout our study. The mean differences and 95% confidence intervals for glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), homeostatic model assessment beta cell function (HOMA-β), and low-density lipoprotein (LDL) were evaluated for the efficacy outcomes of gemigliptin as compared to those of placebo and other oral antidiabetic drugs (OADs). In conclusion, we found that gemigliptin was superior to placebo and comparable to other OADs in terms of the effect on HbA1c, FPG, HOMA-β, and LDL. Further, gemigliptin was more effective than other OADs in HbA1c and HOMA-β in Bayesian inference analysis and statistically significant to other OADs in HbA1c and HOMA-β in sensitivity analysis excluding metformin. However, to confirm the results, more studies need to be analysed and the minimum clinically important difference must be applied.

A review upon medicinal perspective and designing rationale of DPP-4 inhibitors

Type 2 Diabetes Mellitus (T2DM) is one of the highly prevalence disorder and increasing day by day worldwidely. T2DM is a metabolic disorder, which is characterized by deficiency in insulin or resistance to insulin and thus increases the glucose levels in the blood. Various approaches are there to treat diabetes but still there is no cure for this disease. DPP-4 inhibitor is a privileged target in the field of drug discovery and provides various opportunities in exploring this target for development of molecules as antidiabetic agents. DPP-4 acts by inhibiting the incretin action and thus decreases the level of blood glucose by imparting minimal side effects. Sitagliptin, vildagliptin, linagliptin etc. are the different DPP-4 based drugs approved throughout the world for the treatment of diabetes mellitus. Cyanopyrrolidines, triazolopiperazine amide, pyrrolidines are basic core nucleus present in various DPP-4 inhibitors and has potential effects. In the past few years, researchers had applied various approaches to synthesize potent DPP-4 inhibitors as antidiabetic agent without side effects like weight gain, cardiovascular risks, retinopathy etc. This review will also emphasize the recent strategies and rationale utilized by researchers for the development of DPP-4 inhibitors. This review also reveals about the various other approaches like molecular modelling, ligand based drug designing, high throughput screening etc. are used by the various research group for the development of potential DPP-4 inhibitors.

Structure-Activity Relationship Analysis of Cocrystallized Gliptin-like Pyrrolidine, Trifluorophenyl, and Pyrimidine-2,4-Dione Dipeptidyl Peptidase-4 Inhibitors

Approved and potent reported dipeptidyl peptidase-4 (DPP-4) inhibitors with gliptin-like structures are classified here according to their structures and mechanisms of the inhibition in three groups: (i) those with pyrrolidine or analogs as P1 fragment with α-aminoacyl linker, (ii) structures with trifluorophenyl moiety or analogs as P1 fragment with β-aminobutanoyl linker, and (iii) DPP-4 inhibitors with pyrimidine-2,4-dione or analogs as P1' fragment. The structure-activity relationship analysis was performed for those whose cocrystallized structures with the enzyme were published. While inhibitors with pyrrolidine and trifluorophenyl moiety or analogs as P1 fragment bind in a similar way in S1, S2 and S2 extensive domains of the enzyme, the binding mode of pyrimidine-2,4-dione derivatives/analogs differs with additional interactions in S1' and S2' pockets. Three general schemes of fragmented gliptins and gliptin-like structures with the enzyme and protein-ligand interaction fingerprints were made, which might be useful in the creation of DPP-4 inhibitor's design strategies.

Efficacy and Safety of the Novel Dipeptidyl Peptidase-4 Inhibitor Gemigliptin in the Management of Type 2 Diabetes: A Meta-Analysis

BACKGROUND

No meta-analysis has holistically analysed and summarised the efficacy and safety of gemigliptin in type 2 diabetes. The meta-analysis addresses this knowledge gap.

METHODS

Electronic databases were searched for randomised controlled trials (RCTs) involving diabetes patients receiving gemigliptin in the intervention arm and placebo/active comparator in the control arm. The primary outcome was change in haemoglobin A1c (HbA1c). The secondary outcomes were alterations in glucose, glycaemic targets, lipids, insulin resistance, and adverse events.

RESULTS

Data from 10 RCTs involving 1,792 patients were analysed. Four had an active control group (ACG), with metformin/dapagliflozin/sitagliptin/glimepiride as the active comparator; six had a passive control group (PCG), with placebo/rosuvastatin as controls. HbA1c reduction by gemigliptin at 24 weeks was comparable to ACG (mean difference [MD], 0.09%; 95% confidence interval [CI], -0.06 to 0.23; P=0.24; I2=0%; moderate certainty of evidence [MCE]), but superior to PCG (MD, -0.91%; 95% CI, -1.18 to -0.63); P<0.01; I2=89%; high certainty of evidence [HCE]). Gemigliptin was superior to PCG regarding achieving HbA1c <7% (12 weeks: odds ratio [OR], 5.91; 95% CI, 1.34 to 26.08; P=0.02; I2=74%; 24 weeks: OR, 4.48; 95% CI, 2.09 to 9.60; P<0.01; I2=69%; HCE). Gemigliptin was comparable to ACG regarding achieving HbA1c <7% after 24 weeks (OR, 0.92; 95% CI, 0.52 to 1.63; P=0.77; I2=66%; MCE). Adverse events were similar between the gemigliptin and control groups (risk ratio [RR], 1.06; 95% CI, 0.82 to 1.36; P=0.66; I2=35%; HCE). The gemigliptin group did not have increased hypoglycaemia (RR, 1.19; 95% CI, 0.62 to 2.28; P=0.61; I2=19%; HCE).

CONCLUSION

Gemigliptin has good glycaemic efficacy and is well-tolerated over 6 months of use.

Pharmacokinetic and Pharmacodynamic Comparison of Two Formulations of a Fixed-Dose Combination of Gemigliptin/Rosuvastatin 50/20 mg: A Randomized, Open-Label, Single-Dose, Two-Way Crossover Study

Purpose

A fixed-dose combination (FDC) of gemigliptin/rosuvastatin 50/20 mg as a monolayer tablet has been used to treat patients with both type 2 diabetes mellitus and dyslipidemia. To improve the stability of the FDC, a new FDC formulation as a bilayer tablet was developed. This study aimed to compare the pharmacokinetics (PKs) and pharmacodynamics (PDs) of the FDC of gemigliptin/rosuvastatin 50/20 mg between the newly developed bilayer tablet and the approved monolayer tablet in healthy subjects.

Materials and Methods

A randomized, open-label, single-dose, two-treatment, two-way crossover study was conducted. Subjects received a single dose of the FDC of gemigliptin/rosuvastatin 50/20 mg as the bilayer tablet or the monolayer tablet in each period with a 7-day washout. For PK and PD analyses, serial blood samples were collected up to 72 hours after dosing to determine plasma concentrations of gemigliptin, its active metabolite LC15-0636 and rosuvastatin, and plasma dipeptidyl peptidase-4 (DPP-4) activity. PK and PD parameters were calculated using non-compartmental methods and compared between the two formulations.

Results

A total of 48 healthy subjects were randomized, and 45 subjects completed the study. The concentration-time profiles of gemigliptin, LC15-0636 and rosuvastatin were comparable between the two formulations. All geometric mean ratios (90% confidence intervals) of the bilayer tablet to the monolayer tablet for maximum plasma concentration and area under concentration-time curve from 0 to last measurable time point of the three compounds fulfilled the bioequivalence criteria of 0.80-1.25. Likewise, area under plasma DPP-4 activity inhibition from baseline-time curve from 0 to last measurable time point and maximum inhibition of plasma DPP-4 activity were similar between the two formulations.

Conclusion

The FDC of gemigliptin/rosuvastatin 50/20 mg as the bilayer tablet showed equivalent PK and PD properties with the FDC of gemigliptin/rosuvastatin 50/20 mg as the monolayer tablet in healthy subjects. These results suggest that the newly developed bilayer tablet can become an alternative formulation to the commercially available monolayer tablet.

An evaluation of drug lag for new drugs approved by the Indian regulator relative to the United States, European Union, and Japanese regulatory agencies: A 15-year analysis (2004-2018)

Background:

The approval process of every drug regulatory agency differs, and hence, the time required for the approval of a new drug varies. This results in a drug lag and India is no exception to this phenomenon. A drug lag precludes Indian patients from accessing new medicines at the same time as they are approved elsewhere. Against this backdrop, we assessed the absolute and relative drug lags of the Indian regulator relative to three regulators in mature markets, namely United States (US), European Union (EU), and Japan.

Methods:

International nonproprietary names were used to identify new drugs. Their dates of approval (2004-2018) from the online database of four regulatory agencies were identified. Both absolute and relative drug lags were calculated for India as compared to US, EU, and Japan as well for all the agencies relative to the Indian regulator.

Results:

We identified a total of 453, 473, 424, and 472 new drugs approved over the study period in India, US, EU, and Japan, respectively. The absolute drug lag of Central Drugs Standard Control Organization (CDSCO) was 19 and 18 relative to the US Food and Drug Administration (FDA) and Japan Pharmaceuticals and Medical Devices Agency (PMDA), respectively. The relative drug lag for the CDSCO vis-a-vis the US FDA, European Medicines Agency, and PMDA was 43.2 (2.1–1287.8), 25.6 (0.03–1310.5), and 30.3 (1.2–1242) months, respectively.

Conclusion:

Our study shows a significant drug lag between India and other three developed nations (US, EU, and Japan). However, in some therapeutic areas, Indian regulator has proactively approved new drugs much before other agencies. The New Drugs and Clinical Trials Rule of 2019 has brought hope for reduction in drug lag in the near future.

Effect of Dipeptidyl Peptidase-4 (DPP-4) Inhibition on Biomarkers of Kidney Injury and Vascular Calcification in Diabetic Kidney Disease: A Randomized Controlled Trial

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors improve glycemic control and have pleiotropic effects on kidney injury, albuminuria, and vascular inflammation, especially in animal models. We evaluated the effects of a potent DPP4 inhibitor (gemigliptin) on these processes among patients with diabetic kidney disease (DKD).

METHODS

This study employed a multicenter, prospective, randomized, placebo-controlled design. A total of 201 participants were enrolled and randomly assigned to one of two groups, one received treatment with 50 mg gemigliptin daily along with standard care for diabetes mellitus for 6 months. The changes in the coronary calcium score (CAC score), cardio-ankle vascular index (CAVI), estimated glomerular filtration rate (eGFR), vascular calcification level, and tubular renal injury marker expression were evaluated at baseline and 6 months.

RESULTS

In total, 182 patients completed the study. Significant reductions in hemoglobin A1C levels were observed in both groups. The changes in the CAC score, CAVI, eGFR, and level of proteinuria over the 6 months of the study did not significantly differ between the gemigliptin and control groups. However, biomarkers of vascular calcification, including serum bone alkaline phosphatase and kidney injury, including urine neutrophil gelatinase-associated lipocalin (NGAL)/Cr and urine liver fatty acid-binding protein (L-FABP)/Cr, were improved significantly in the gemigliptin treatment group compared with the control group. No serious adverse events were observed during the study.

CONCLUSION

Our study showed that gemigliptin significantly improved the expression of renal tubular injury biomarkers and vascular calcification levels among patients with DKD; however, gemigliptin did not affect renal function or coronary calcification compared with those observed in the control. A larger study with a longer follow-up is essential to verify these beneficial effects. Clinical Trials. This trial is registered with ClinicalTrials.Gov Identifier NCT04705506.

Development and Validation of a Rapid and Sensitive Method for the Simultaneous Estimation of Gemigliptin and Teneligliptin in Bulk and Dosage Forms by Using Liquid Chromatography-tandem Mass Spectrometry

Background:

A simple and sensitive ultra-performance liquid chromatography-mass spectrometry method was developed and validated to measure the concentrations of gemigliptin (GEM) and teneligliptin (TEN) using pioglitazone (PIO) as an internal standard.

Methods:

Chromatographic separation of two gliptins was achieved on a C-18 (100 mm X 2.1 mm, 2.7 μm) column using a mobile phase consisting of formic acid in water (0.1 % v/ v): acetonitrile in gradient elution. Electrospray ionization (ESI) source was operated in positive mode (ionization). Targeted MS-MS mode on a quadrupole time of flight (Q-TOF) mass spectrometer was used to quantify the drugs utilizing the mass transitions of 490.1 (m/z), 427.2 (m/z) and 357.1 (m/z) for GEM, TEN and PIO, respectively.

Results:

As per ICH Q2R1 guidelines, a detailed validation of the method was carried out and the standard curves were found to be linear between the concentration ranges of 509.8-1529.4 ng mL-1 and 510.6-1531.7 ng mL-1 for GEM and TEN, respectively. Precision and accuracy results were found to be within the acceptable limits. The mean recovery was found to be 98.8± 0.76 % (GEM) and 98.6 ±0.98 % (TEN), respectively.

Conclusions:

The optimized validated UPLC-QTOF (MS-MS) method offered the advantage of shorter analytical times and higher sensitivity and selectivity to the nanogram level.

The vasodilatory effect of gemigliptin via activation of voltage-dependent K+ channels and SERCA pumps in aortic smooth muscle

This study investigated the vasodilatory effects and acting mechanism of gemigliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor. Tests were conducted in aortic rings pre-contracted with phenylephrine. Gemigliptin induced dose-dependent vasodilation of the aortic smooth muscle. Several pre-treatment groups were used to investigate the mechanism of action. While pre-treatment with paxilline, a large-conductance Ca²⁺-activated K⁺ channel inhibitor, glibenclamide, an ATP-sensitive K⁺ channel inhibitor, and Ba²⁺, an inwardly rectifying K⁺ channel inhibitor, had no impact on the vasodilatory effect of gemigliptin, pre-treatment with 4-aminopyridine, a voltage-dependent K⁺ (Kv) channel inhibitor, effectively attenuated the vasodilatory action of gemigliptin. In addition, pre-treatment with sarcoplasmic/endoplasmic reticulum Ca²⁺-ATPase (SERCA) pump inhibitors thapsigargin and cyclopiazonic acid significantly reduced the vasodilatory effect of gemigliptin. cAMP/PKA-related or cGMP/PKG-related signaling pathway inhibitors, including adenylyl cyclase inhibitor SQ 22536, PKA inhibitor KT 5720, guanylyl cyclase inhibitor ODQ, and PKG inhibitor KT 5823 did not alter the vasodilatory effect of gemigliptin. Similarly, elimination of the endothelium and pre-treatment with a nitric oxide (NO) synthase inhibitor (L-NAME) or small- and intermediate-conductance Ca²⁺-activated K⁺ channels (apamin and TRAM-34, respectively) did not change the gemigliptin effect. These findings suggested that gemigliptin induces vasodilation through the activation of Kv channels and SERCA pumps independent of cAMP/PKA-related or cGMP/PKG-related signaling pathways and the endothelium. Therefore, caution is required when prescribing gemigliptin to the patients with hypotension and diabetes.

Dipeptidyl Peptidase-4 Inhibitors versus Other Antidiabetic Drugs Added to Metformin Monotherapy in Diabetic Retinopathy Progression: A Real World-Based Cohort Study

BACKGROUND

To investigate the effects of dipeptidyl peptidase-4 inhibitor (DPP4i) as add-on medications to metformin on progression of diabetic retinopathy (DR) in patients with type 2 diabetes mellitus, compared with sulfonylurea (SU) or thiazolidinedione (TZD).

METHODS

We identified 4,447 patients with DPP4i, 6,136 with SU, and 617 with TZD in addition to metformin therapy from the database of Korean National Health Insurance Service between January 2013 and December 2015. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) for DR progression. The progression of DR was defined by the procedure code of panretinal photocoagulation, intravitreal injection or vitrectomy; or the addition of diagnostic code of vitreous hemorrhage, retinal detachment, or neovascular glaucoma.

RESULTS

The age and sex-adjusted HR of DR progression was 0.74 for DPP4i add-on group compared with SU add-on group (95% confidence interval [CI], 0.62 to 0.89). This lower risk of DR progression remained significant after additional adjustments for comorbidities, duration of metformin therapy, intravitreal injections and calendar index year (HR, 0.80; 95% CI, 0.66 to 0.97).

CONCLUSION

This population-based cohort study showed that the use of DPP4i as add-on therapy to metformin did not increase the risk of DR progression compared to SU.

Effect of gemigliptin on cardiac ischemia/reperfusion and spontaneous hypertensive rat models

Diabetes is associated with an increased risk of cardiovascular complications. Dipeptidyl peptidase-4 (DPP-IV) inhibitors are used clinically to reduce high blood glucose levels as an antidiabetic agent. However, the effect of the DPP-IV inhibitor gemigliptin on ischemia/reperfusion (I/R)-induced myocardial injury and hypertension is unknown. In this study, we assessed the effects and mechanisms of gemigliptin in rat models of myocardial I/R injury and spontaneous hypertension. Gemigliptin (20 and 100 mg/kg/d) or vehicle was administered intragastrically to Sprague-Dawley rats for 4 weeks before induction of I/R injury. Gemigliptin exerted a preventive effect on I/R injury by improving hemodynamic function and reducing infarct size compared to the vehicle control group. Moreover, administration of gemigliptin (0.03% and 0.15%) powder in food for 4 weeks reversed hypertrophy and improved diastolic function in spontaneously hypertensive rats. We report here a novel effect of the gemigliptin on I/R injury and hypertension.

Efficacy and Safety of Switching to Teneligliptin in Patients with Type 2 Diabetes Inadequately Controlled with Dipeptidyl Peptidase-4 Inhibitors: A 12-Week Interim Report

INTRODUCTION

Teneligliptin, an antidiabetic agent classified as a class III dipeptidyl peptidase-4 (DPP-4) inhibitor, has a unique structural feature that provides strong binding to DPP-4 enzymes. We investigated the efficacy and safety of switching patients with type 2 diabetes mellitus (T2DM) who had inadequate glycemic control on a stable dose of other DPP-4 inhibitors to teneligliptin.

METHODS

Patients with T2DM whose glycosylated hemoglobin (HbA1c) levels were ≥ 7% despite taking DPP-4 inhibitors other than teneligliptin, with or without other hypoglycemic agents, for at least 3 months were enrolled. The DPP-4 inhibitors taken before participating in the study were switched to 20 mg qd teneligliptin, and this was to be maintained for 52 weeks. The primary end point was the change in HbA1c levels after 12 weeks. Metabolic parameters including fasting plasma glucose (FPG) and blood lipids were assessed also. To assess safety, adverse and hypoglycemic events were monitored. The data from baseline to week 12 were used for analysis in this interim report.

RESULTS

The mean change in HbA1c levels from baseline to week 12 was - 0.44%. At week 12, the percentage of patients achieving HbA1c < 7.0% was 31.6% and that of achieving HbA1c < 6.5% was 11.4%, respectively. In 41.2% of patients, the HbA1c levels decreased by at least 0.5% at 12 weeks. The mean change in FPG levels from baseline to week 12 was - 11.5 mg/dl. No severe hypoglycemia was reported.

CONCLUSION

After switching to teneligliptin, HbA1c levels decreased significantly in patients with T2DM inadequately controlled with other DPP-4 inhibitors.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03793023.

FUNDING

Handok Inc.

Incretin Mimetics as Rational Candidates for the Treatment of Traumatic Brain Injury

Traumatic brain injury (TBI) is becoming an increasing public health issue. With an annually estimated 1.7 million TBIs in the United States (U.S) and nearly 70 million worldwide, the injury, isolated or compounded with others, is a major cause of short- and long-term disability and mortality. This, along with no specific treatment, has made exploration of TBI therapies a priority of the health system. Age and sex differences create a spectrum of vulnerability to TBI, with highest prevalence among younger and older populations. Increased public interest in the long-term effects and prevention of TBI have recently reached peaks, with media attention bringing heightened awareness to sport and war related head injuries. Along with short-term issues, TBI can increase the likelihood for development of long-term neurodegenerative disorders. A growing body of literature supports the use of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and glucagon (Gcg) receptor (R) agonists, along with unimolecular combinations of these therapies, for their potent neurotrophic/neuroprotective activities across a variety of cellular and animal models of chronic neurodegenerative diseases (Alzheimer's and Parkinson's diseases) and acute cerebrovascular disorders (stroke). Mild or moderate TBI shares many of the hallmarks of these conditions; recent work provides evidence that use of these compounds is an effective strategy for its treatment. Safety and efficacy of many incretin-based therapies (GLP-1 and GIP) have been demonstrated in humans for the treatment of type 2 diabetes mellitus (T2DM), making these compounds ideal for rapid evaluation in clinical trials of mild and moderate TBI.

Clinical Use of DPP-4 Inhibitors

DPP-4 inhibitors were introduced for the treatment of type 2 diabetes in 2006. They stimulate insulin secretion and inhibit glucagon secretion by elevating endogenous GLP-1 concentrations without an intrinsic hypoglycaemia risk. Their efficacy potential to lower HbA1c is in the range between 0.5 and 1.0% and their safety profile is favorable. DPP-4 inhibitors are body weight neutral and they have demonstrated cardiovascular safety. Most compounds can be used in impaired renal function. Guidelines suggest the additional use of DPP-4 inhibitors after metformin failure in patients that do not require antidiabetic therapy with proven cardiovascular benefit. Recently, DPP-4 inhibitors have increasingly replaced sulfonylureas as second line therapy after metformin failure and many metformin/DPP-4 inhibitor fixed dose combinations are available. In later stages of type 2 diabetes, DPP-4 inhibitors are also recommended in the guidelines in triple therapies with metformin and SGLT-2 inhibitors or with metformin and insulin. A treatment with DPP-4 inhibitors should be stopped when GLP-1 receptor agonists are used. DPP-4 inhibitors can be used as monotherapy when metformin is contraindicated or not tolerated. Some studies have shown value of initial metformin-DPP-4 inhibitor combination therapy in special populations. This article gives an overview on the clinical use of DPP-4 inhibitors.

Pharmacokinetic Interactions Between Gemigliptin and Metformin, and Potential Differences in the Pharmacokinetic Profile of Gemigliptin Between the Mexican and Korean Populations: A Randomized, Open-label Study in Healthy Mexican Volunteers

PURPOSE

The aim of this study was to assess the pharmacokinetic interactions between a newly developed dipeptidyl peptidase (DPP)-4 inhibitor, gemigliptin, and metformin in healthy Mexican male volunteers, and the differences in the pharmacokinetic profile of gemigliptin between Korean and Mexican healthy volunteers.

METHODS

This was a multiple-dose, randomized, open-label, 3-way, 3-period crossover study. Subjects were randomized to 1 of 3 treatment sequences and received gemigliptin 50mg once a day, metformin1000mg BID, or both drugs during a 7-day treatment period, and underwent sampling for pharmacokinetic analysis and tolerability assessments. Point estimates and 90% CIs of C_max,ss and AUCτ,ss least squares mean (LSM) ratios of the concurrent administration of gemigliptin + metformin to the administration of monotherapy with either drug were obtained, and the pharmacokinetic profile of gemigliptin observed was compared with that in healthy Korean volunteers studied during the initial development of gemigliptin.

FINDINGS

The coadministration of gemigliptin + metformin did not affect the pharmacokinetic characteristics of gemigliptin (LSM ratio [90% CI] for C_max,ss and AUC_τ,ss: 0.98 [0.87-1.10] and 0.94 [0.91-0.98], respectively) or metformin (LSM ratio [90% CI] for C_max,ss and AUC_τ,ss: 0.97 [0.88-1.08] and 1.02 [0.93-1.12], respectively) when administered as monotherapy and was well tolerated. In contrast with Korean healthy volunteers, Mexican subjects showed a modestly higher gemigliptin exposure (LSM ratio [90% CI] for AUC_τ,ss: 1.22 [1.14-1.31]).

IMPLICATIONS

The results of this study support, in ethnically different populations, the absence of drug-drug interactions between gemigliptin and metformin previously shown in Korean healthy volunteers. Considering the flat effect-concentration curve and wide therapeutic range of gemigliptin, the pharmacokinetic profile of gemigliptin observed in healthy Mexican and Korean subjects suggests that gemigliptin use in Mexican patients may be associated with outcomes, in terms of efficacy and tolerability, similar to those observed in the Korean population. ClinicalTrials.gov identifier: NCT03310749.

Protective effects of gemigliptin against type II collagen degradation in human chondrocytes

Degradation of components of the extracellular matrix such as type II collagen in articular cartilage induced by matrix metalloproteinases (MMPs) has been considered as a major pathological characteristic of osteoarthritis (OA). Gemigliptin is a potent and a highly selective dipeptidyl peptidase-IV (DPP-IV) inhibitor, which has been clinically used as an oral agent for the treatment of type 2 diabetes. However, the effects of gemigliptin on articular cartilage destruction and the pathogenesis of OA remain unknown. In the current study, we addressed for the first time the inhibitory property of gemigliptin against interleukin-1β (IL-1β)-induced degradation of type II collagen in human chondrocytes. Our results demonstrate that gemigliptin treatment inhibited the expression of matrix metalloproteinase 1 (MMP-1), matrix metalloproteinase 3 (MMP-3), and matrix metalloproteinase 13 (MMP-13) at both the gene and protein levels. Mechanistically, our results indicate that gemigliptin inhibited activation of the nuclear factor-κB (NF-κB) signaling pathway by suppressing phosphorylation of IκB kinase (IKK)/nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor α (IκBα) and p38. Our results implicate that gemigliptin treatment might be a potential therapeutic strategy for chondroprotective therapy.

Comparative Cardiovascular Risks of Dipeptidyl Peptidase-4 Inhibitors: Analyses of Real-world Data in Korea

Background and Objectives

To compare cardiovascular disease (CVD) risk associated with 5 different dipeptidyl peptidase-4 inhibitors (DPP-4is) in people with type 2 diabetes.

Methods

We identified 534,327 people who were newly prescribed sitagliptin (n=167,157), vildagliptin (n=67,412), saxagliptin (n=29,479), linagliptin (n=220,672), or gemigliptin (n=49,607) between January 2013 and June 2015 using the claims database of the Korean National Health Insurance System. A Cox proportional hazards model was used to estimate hazard ratios (HRs) for major CVD events (myocardial infarction, stroke, or death) among users of different DPP-4is. The model was adjusted for sex, age, duration of DPP-4i use, use of other glucose-lowering drugs, use of antiplatelet agents, hypertension, dyslipidemia, atrial fibrillation, chronic kidney disease, microvascular complications of diabetes, Charlson comorbidity index, and the calendar index year as potential confounders.

Results

Compared to sitagliptin users, the fully adjusted HRs for CVD events were 0.97 (95% confidence interval [CI], 0.94–1.01; p=0.163) for vildagliptin, 0.76 (95% CI, 0.71–0.81; p<0.001) for saxagliptin, 0.95 (95% CI, 0.92–0.98; p<0.001) for linagliptin, and 0.84 (95% CI, 0.80–0.88; p<0.001) for gemigliptin.

Conclusions

Compared to sitagliptin therapy, saxagliptin, linagliptin, and gemigliptin therapies were all associated with a lower risk of cardiovascular events.

Comparative efficacy and safety of gemigliptin versus linagliptin in type 2 diabetes patients with renal impairment: A 40-week extension of the GUARD randomized study

AIMS

The long-term safety and efficacy of gemigliptin was evaluated in the present extension study after a 12-week study during a 40-week follow-up period.

METHODS

The main study was a randomized, placebo-controlled, double-blinded, phase IIIb study in which 50 mg of gemigliptin (N = 66) or placebo (N = 66) was administered to patients with type 2 diabetes mellitus (T2DM) and moderate or severe renal impairment over a 12-week period. Patients with a glycated haemoglobin (HbA1c) level of 7% to 11% and an estimated glomerular filtration rate (eGFR) of 15 to 59 mL/min/1.73 m² were enrolled in the main study. After 12 weeks, patients in the gemigliptin group continued to receive gemigliptin (N = 50), whereas patients in the placebo group were transitioned from placebo to linagliptin (N = 52). Each group received the indicated treatment over the subsequent 40-week period. A total of 102 patients consented to participate in the extension study, and 79 patients ultimately completed the study.

RESULTS

The HbA1c levels of both groups were significantly reduced at week 52 compared with baseline. Specifically, the adjusted mean change ± standard error in HbA1c level in the gemigliptin and placebo/linagliptin groups was 1.00% ± 0.21% and 0.65% ± 0.22% lower at week 52 than at baseline (P < .001 and P = .003), respectively. No significant difference in the change in HbA1c level was found between the 2 groups (P = .148). Trends in fasting plasma glucose, fructosamine and glycated albumin levels in the 2 groups were similar to trends in HbA1c levels. The eGFR of both groups was also significantly lower at week 52 than at baseline, and no significant difference in change in eGFR was found between the 2 groups. In contrast, both drugs had little effect on urinary albumin excretion, although both drugs significantly reduced the urinary type IV collagen level. The overall rates of adverse events were similar between the 2 groups.

CONCLUSIONS

Gemigliptin and linagliptin did not differ with respect to safety and efficacy in patients with T2DM and renal impairment. The 2 drugs had similar glucose-lowering effects, and the changes in eGFR and albuminuria were also similar. Additionally, the risk of side effects, including hypoglycaemia, was similar between the 2 groups.

Protective Effects of Gemigliptin, a Dipeptidyl Peptidase-4 Inhibitor, against Cisplatin-Induced Nephrotoxicity in Mice

Dipeptidyl peptidase-4 (DPP-4) inhibitors are widely used antihyperglycemic agents for the treatment of type 2 diabetes mellitus. Recently, the pleiotropic actions of DPP-4 inhibitors have drawn much attention. In the present study, we aimed to examine whether gemigliptin, a recently developed DPP-4 inhibitor, could protect against cisplatin-induced nephrotoxicity. We showed that pretreatment with gemigliptin attenuated cisplatin-induced renal dysfunction, as shown by analysis of plasma creatinine levels and blood urea nitrogen and histological damage. Elevated plasma levels of active glucagon-like peptide-1 were observed in gemigliptin-pretreated mice after cisplatin treatment, compared to that in cisplatin alone-treated mice. Gemigliptin attenuated cisplatin-induced apoptotic cell death, as assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and Western blot analysis in the kidneys. Gemigliptin also decreased the plasma levels of tumor necrosis factor-α and monocyte chemoattractant protein-1 and attenuated nuclear staining of nuclear factor kappa-B p65 in the kidneys. In addition, gemigliptin increased the protein expression of heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1) in the kidneys of cisplatin-treated mice. Taken together, these results suggest that pretreatment with gemigliptin protects against cisplatin-induced nephrotoxicity in mice, possibly via inhibition of apoptotic cell death and inflammatory responses through induction of HO-1 and NQO1 expression.

Gemigliptin: Newer Promising Gliptin for Type 2 Diabetes Mellitus

The dipeptidyl peptidase-4 (DPP-4) inhibitors have facilitated the management of type 2 diabetes mellitus (T2DM) owing to their superior efficacy and safety with low incidence of adverse effects. Gemigliptin is a new member of this family of drugs, and studies have revealed certain advantages of gemigliptin use compared to its previous congeners. Besides, this drug has also been studied for the treatment of T2DM as monotherapy, in combination with metformin or other oral antidiabetic drugs and in T2DM with moderate-to-severe renal failure. In this review, we explore the published data highlighting the pharmacology, efficacy, and safety of gemigliptin along with its recommendations for use in patients with T2DM.

Efficacy and safety of gemigliptin, a dipeptidyl peptidase-4 inhibitor, in patients with type 2 diabetes mellitus inadequately controlled with combination treatment of metformin and sulphonylurea: a 24-week, multicentre, randomized, double-blind, placebo-controlled study (TROICA study)

AIMS

To assess the efficacy and safety of gemigliptin, a dipeptidyl peptidase-4 inhibitor, added to metformin and sulphonylurea in patients with type 2 diabetes (T2DM).

MATERIALS AND METHODS

We conducted a randomized, double-blind, placebo-controlled trial in 219 Korean patients inadequately controlled with metformin and glimepiride. Participants were randomized to gemigliptin 50 mg once daily or placebo added to metformin and glimepiride. The primary endpoint was change in glycated haemoglobin (HbA1c) level from baseline to week 24.

RESULTS

The baseline HbA1c was 8.2% in both groups. The addition of gemigliptin to metformin and glimepiride significantly reduced HbA1c levels at week 24 compared with placebo (between-group difference in adjusted mean change -0.87%, 95% confidence interval [CI] -1.09% to -0.64%). Fasting plasma glucose level was also significantly reduced with gemigliptin (-0.93 mmol/L, 95% CI -1.50 to -0.35 mmol/L), and a higher proportion of participants achieved an HbA1c level of <7% (39.3% vs 5.5%; P <.001) in the gemigliptin group than in the placebo group. Total cholesterol and LDL cholesterol were modestly but significantly reduced in the gemigliptin group compared with the placebo group (-0.21 mmol/L, 95% CI -0.38 to -0.03 mmol/L for total cholesterol, -0.18 mmol/L, 95% CI -0.34 to -0.01 mmol/L for LDL cholesterol). The incidence of hypoglycaemia was 9.4% in the gemigliptin group and 2.7% in the placebo group.

CONCLUSIONS

Gemigliptin significantly improved glycaemic control in patients with T2DM inadequately controlled with metformin and sulphonylurea. The incidence of hypoglycaemia was higher with gemigliptin than with placebo, which highlights the importance of optimal dose adjustment for sulphonylurea.

Lung ischemia reperfusion injury: the therapeutic role of dipeptidyl peptidase 4 inhibition

Dipeptidyl peptidase 4 (DPP4) is a cell surface protease that has been reported to play a role in glucose homeostasis, cancer, HIV, autoimmunity, immunology and inflammation. A role for DPP4 in ischemia-reperfusion injury (IRI) in the heart has been established. Dipeptidyl peptidase 4 inhibition (DPP4i) appeared to decrease infarct size, improves cardiac function and promotes myocardial regeneration. Lung ischemia reperfusion injury is caused by a complex mechanism in which macrophages and neutrophils play an important role. Generation of reactive oxygen species (ROS), uncoupling of nitric oxide synthase (NOS), activation of nuclear factor-κB (NF-κB), activation of nicotinamide adenine dinucleotide phosphate metabolism, and generation of pro-inflammatory cytokines lead to acute lung injury (ALI). In this review we present the current knowledge on DPP4 as a target to treat IRI in the lung. We also provide evidence of the roles of the DPP4 substrates glucagon-like peptide 1 (GLP-1), vasoactive intestinal peptide (VIP) and stromal cell-derived factor-1α (SDF-1α) in protection against oxidative stress through activation of the mitogen-activated protein kinase (MAPK) 1/2 and phosphatidylinositol 3'-kinase (PI3K)/Akt signal transduction pathways.

Effects of gemigliptin, a dipeptidyl peptidase-4 inhibitor, on lipid metabolism and endotoxemia after a high-fat meal in patients with type 2 diabetes

We aimed to investigate the effects of gemigliptin, a dipeptidyl peptidase-4 inhibitor, on postprandial lipoprotein levels and endotoxemia in a randomized, double-blind, placebo-controlled, crossover study. Ten people with type 2 diabetes mellitus (T2DM), inadequately controlled with oral antidiabetic medications and/or lifestyle modification, were randomized to gemigliptin or placebo for 4 weeks. At the end of each treatment phase, the study participants underwent a high-fat meal tolerance test and needle aspiration of abdominal subcutaneous adipose tissue. The median (range) fasting and total area under the curve of apolipoprotein B48 (ApoB48) were significantly lower with gemigliptin than with placebo (2.9 [1.5-15.8] µg/mL vs 4.2 [1.3-23.4] µg/mL; P = .020; 35.3 [14.4-87.4] µg/mL × hour vs 42.2 [17.5-109.0] µg/mL × hour; P = .020, respectively), whereas apolipoprotein B100 showed no significant difference. Serum endotoxin levels were undetectable in 70% of the samples, so we were not able to evaluate the effect of gemigliptin on endotoxemia. The gene expression of inflammatory cytokines in subcutaneous adipose tissue was not affected by gemigliptin. Gemigliptin reduced ApoB48 levels after a high-fat meal in participants with T2DM. Whether systemic endotoxin levels can be reduced by gemigliptin requires further investigation.