Assessment of the pharmacokinetics of co-administered metformin and lobeglitazone, a thiazolidinedione antihyperglycemic agent, in healthy subjects

PPARs in Clinical Experimental Medicine after 35 Years of Worldwide Scientific Investigations and Medical Experiments

This year marks the 35th anniversary of Professor Walter Wahli's discovery of the PPARs (Peroxisome Proliferator-Activated Receptors) family of nuclear hormone receptors. To mark the occasion, the editors of the scientific periodical Biomolecules decided to publish a special issue in his honor. This paper summarizes what is known about PPARs and shows how trends have changed and how research on PPARs has evolved. The article also highlights the importance of PPARs and what role they play in various diseases and ailments. The paper is in a mixed form; essentially it is a review article, but it has been enriched with the results of our experiments. The selection of works was subjective, as there are more than 200,000 publications in the PubMed database alone. First, all papers done on an animal model were discarded at the outset. What remained was still far too large to describe directly. Therefore, only papers that were outstanding, groundbreaking, or simply interesting were described and briefly commented on.

Lobeglitazone and Its Therapeutic Benefits: A Review

Lobeglitazone is a newer oral hypoglycemic agent that has been tested in type 2 diabetes mellitus (T2DM). We aim to conduct a narrative review to find out the therapeutic benefits of lobeglitazone in patients with T2DM. We scientifically searched the electronic database of PubMed from inception until September 12, 2023, using Medical Subject Heading (MeSH) keywords. Additionally, we searched for pre-clinical trials related to lobeglitazone. We retrieved all available results of phase 1 to phase 3 studies of lobeglitazone in T2DM. Subsequently, we reviewed the results narratively. Three double-blind, randomized, placebo-controlled studies and a phase 3 trial of lobeglitazone showed that 0.5 mg daily dose exhibits effective therapeutic activity in glycemic, lipid, and hepatic control, and is also used as a secondary treatment in non-alcoholic fatty liver disease. Lobeglitazone exhibits as much antidiabetic activity as other thiazolidinediones such as pioglitazone and rosiglitazone. Side effects of lobeglitazone included peripheral edema, weight gain, and bone mineral density, which did not require hospitalization for these effects. This article highlights the pharmacological, pre-clinical, clinical, and safety pharmacology of novel thiazolidinedione lobeglitazone.

Evaluation of pharmacokinetic interactions between lobeglitazone, empagliflozin, and metformin in healthy subjects

Concomitant administration of lobeglitazone, empagliflozin, and metformin is expected to enhance blood glucose-lowering effects and improve medication compliance in patients with diabetes mellitus. In this study, we investigated the pharmacokinetic (PK) interactions and safety of lobeglitazone and co-administered empagliflozin and metformin, which are approved agents used in clinical settings. Two randomized, open-label, multiple-dose, 2-treatment, 2-period, 2-sequence crossover clinical trials (parts 1 and 2) were conducted independently. In part 1, lobeglitazone monotherapy or lobeglitazone, empagliflozin, and metformin triple therapy was administered for 5 days. In part 2, empagliflozin and metformin dual therapy or the abovementioned triple therapy were administered for 5 days. Serial blood samples were collected up to 24 hours after the last dose in each period for PK evaluation. The primary PK parameters (AUC_tau,ss, C_max,ss) of treatment regimens in each study part were calculated and compared. For lobeglitazone, the geometric mean ratios (GMRs) with 90% confidence intervals (CI) for triple therapy over monotherapy were 1.08 (1.03-1.14) for C_max,ss and 0.98 (0.90-1.07) for AUC_tau,ss. For empagliflozin, the GMRs and 90% CIs for triple therapy over dual therapy were 0.87 (0.78-0.97) for C_max,ss and 0.97 (0.93-1.00) for AUC_tau,ss. For metformin, the GMRs and 90% CIs for triple therapy over dual therapy were 1.06 (0.95-1.17) for C_max,ss and 1.04 (0.97-1.12) for AUC_tau,ss. All reported adverse events were mild. The triple therapy consisting of lobeglitazone, empagliflozin, and metformin did not show any clinically relevant drug interactions in relation to the PKs and safety of each drug substance.

Trial Registration

ClinicalTrials.gov Identifier: NCT04334213.

Effects of Hepatic Impairment on the Pharmacokinetic Profile and Safety of Lobeglitazone

In this open-label, single-dose, parallel-group study, we compared the pharmacokinetic profile and safety of lobeglitazone, a thiazolidinedione acting as an agonist for peroxisome proliferator-activated receptors, in patients with hepatic impairment (HI) and healthy matched controls for age, sex, and body weight. After a single oral dose of lobeglitazone (0.5 mg), the lobeglitazone (parent drug) and M7 (major metabolite) plasma concentrations and pharmacokinetic parameters were analyzed and compared between the HI patient groups and healthy matched control groups. The geometric mean ratio (GMR; 90% confidence interval [CI]) for maximum concentration (C_max ) and area under the plasma concentration-time curve from time 0 extrapolated to infinity (AUC_inf ) of lobeglitazone was 1.06 (0.90-1.24) and 1.07 (0.82-1.40), respectively, for mild HI vs control A. The GMR (90%CI) of C_max and AUC_inf was 0.70 (0.56-0.88) and 1.00 (0.72-1.37), respectively, for moderate HI vs control B. For M7, the GMR (90%CI) of C_max and AUC_inf was 1.09 (0.75-1.57) and 1.18 (0.71-1.97), respectively, for mild HI vs control A and 1.50 (0.95-2.38) and 1.79 (1.06-3.04), respectively, for moderate HI vs control B. Notable adverse events or tolerability issues were not observed. Lobeglitazone may be safely used in patients with mild or moderate HI without dose adjustment.

Lobeglitazone: A Novel Thiazolidinedione for the Management of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance and β-cell dysfunction. Among available oral antidiabetic agents, only the thiazolidinediones (TZDs) primarily target insulin resistance. TZDs improve insulin sensitivity by activating peroxisome proliferator-activated receptor γ. Rosiglitazone and pioglitazone have been used widely for T2DM treatment due to their potent glycemic efficacy and low risk of hypoglycemia. However, their use has decreased because of side effects and safety issues, such as cardiovascular concerns and bladder cancer. Lobeglitazone (Chong Kun Dang Pharmaceutical Corporation), a novel TZD, was developed to meet the demands for an effective and safe TZD. Lobeglitazone shows similar glycemic efficacy to pioglitazone, with a lower effective dose, and favorable safety results. It also showed pleiotropic effects in preclinical and clinical studies. In this article, we summarize the pharmacologic, pharmacokinetic, and clinical characteristics of lobeglitazone.

An Assessment of Pharmacokinetic Interaction Between Lobeglitazone and Sitagliptin After Multiple Oral Administrations in Healthy Men

PURPOSE

Patients with type 2 diabetes mellitus require strict blood glucose control, and combination therapy with a thiazolidinedione and dipeptidyl peptidase-4 inhibitors, such as lobeglitazone and sitagliptin, is one of the recommended treatments. The objective of this study was to investigate a possible pharmacokinetic interaction between lobeglitazone and sitagliptin after multiple oral administrations in healthy Korean men.

METHODS

Two randomized, open-label, multiple-dose, 2-way crossover studies were conducted simultaneously in healthy men. In study 1, men were randomly assigned to 1 of 2 sequences, and 1 of the following treatments was administered in each period: 1 tablet of lobeglitazone sulfate (0.5 mg) once daily for 5 days and or 1 tablet each of lobeglitazone sulfate (0.5 mg) and sitagliptin (100 mg) once daily for 5 days. In study 2, men were also randomly assigned to 1 of 2 sequences and the treatments were as follows: 1 tablet of sitagliptin (100 mg) once daily for 5 days or 1 tablet each of sitagliptin (100 mg) and lobeglitazone sulfate (0.5 mg) once daily for 5 days. Serial blood samples were collected up to 48 h after dosing on the fifth day. Plasma drug concentrations were measured by LC-MS/MS. Pharmacokinetic parameters, including C_max,ss and AUC_0-τ , were determined by noncompartmental analysis. The geometric least-square mean (GLSM) ratios and associated 90% CIs of log-transformed C_max,ss and AUC_0-τ for separate or coadministration were calculated to evaluate pharmacokinetic interactions.

FINDINGS

Nineteen men from study 1 and 17 from study 2 completed the pharmacokinetic sampling and were included in the analyses. The GLSM ratios of C_max,ss and AUC_0-τ were 0.9494 (95% CI, 0.8798-1.0243) and 1.0106 (95% CI, 0.9119-1.1198) for lobeglitazone (from study 1) and 1.1694 (95% CI, 1.0740-1.2732) and 1.0037 (95% CI, 0.9715-1.0369) for sitagliptin (from study 2), respectively.

IMPLICATIONS

Except for the slight 17% increase in the sitagliptin C_max,ss value, the pharmacokinetic parameters of lobeglitazone and sitagliptin met the pharmacokinetic equivalent criteria when administered separately or in combination. The increase in C_max of sitagliptin when coadministered with lobeglitazone would not be clinically significant in practice. ClinicalTrials.gov Identifier: NCT02824874 and NCT02827890.

Evaluation of the Pharmacokinetic Interaction Between Lobeglitazone and Dapagliflozin at Steady State

PURPOSE

Coadministration of lobeglitazone and dapagliflozin is expected to result in a blood glucose-lowering effect, followed by a gradual increase, in clinical usage; however, combining drugs could cause negative interactions. This study aimed to evaluate the effect of the coadministration of lobeglitazone and dapagliflozin on their individual pharmacokinetic properties at steady state in healthy male volunteers in the fasted state.

METHODS

This study consisted of 2 parts, each of which was a randomized, open-labeled, multiple-dose, 2-way crossover study in 20 healthy male volunteers in each part. Blood samples were taken periodically over a 48-h period after dosing to derive total plasma lobeglitazone and dapagliflozin pharmacokinetic properties; safety profile was evaluated throughout the study.

FINDINGS

When the pharmacokinetic properties of dapagliflozin were evaluated following its administration alone and in combination with lobeglitazone, point estimate and 90% CI of the geometric mean ratio of dapagliflozin AUC_τ were entirely within the conventional bioequivalence range of 80%-125%. However, although it was not clinically meaningful, its C_ss,max was ~8% lower in subjects receiving multiple doses of dapagliflozin and lobeglitazone than that in those administered dapagliflozin alone. The pharmacokinetic properties of lobeglitazone were evaluated following its administration alone and in combination with dapagliflozin. The geometric mean ratios and 90% CIs of the lobeglitazone C_ss,max and AUC_τ were within the conventional bioequivalence range of 80%-125%.

IMPLICATIONS

Coadministration of lobeglitazone and dapagliflozin had no apparent clinically relevant effects on the pharmacokinetic properties of either drug. Based on these findings, it is anticipated that lobeglitazone and dapagliflozin can be coadministered without dose adjustment. ClinicalTrials.gov identifier: NCT03616392.

Pharmacokinetics of a Lobeglitazone/Metformin Fixed-Dose Combination Tablet (CKD-395 0.5/1000 mg) Versus Concomitant Administration of Single Agents and the Effect of Food on the Metabolism of CKD-395 in Healthy Male Subjects

This study aimed to compare the pharmacokinetic profile of combined CKD-395 0.5/1000 mg treatment with that of the coadministration of lobeglitazone sulfate 0.5 mg and metformin hydrochloride (HCl) extended-release (XR) 1000 mg and assess the effect of food on the pharmacokinetics of CKD-395 0.5/1000 mg. Two clinical trials were conducted as part of an open-label, single-dose, randomized, 2-period, 2-sequence crossover study. In study 1, a total of 26 subjects received either CKD-395 0.5/1000 mg as a test drug or coadministration of lobeglitazone sulfate 0.5 mg and metformin HCl XR 1000 mg individually as a reference treatment under fed conditions. In study 2, a total of 16 subjects received CKD-395 0.5/1000 mg treatment under either fasted or fed conditions. Blood samples were collected at intervals from 0 to 48 hours. In study 1, the geometric mean ratios and 90% confidence intervals of pharmacokinetic parameters for lobeglitazone and metformin were all within 80%-125% in the fed condition. In study 2, there were no high-fat meal effects on the area under the curve extending up to the last sampling time (AUC_last ) of lobeglitazone, but there was a decrease in the maximum plasma concentration (C_max ) of lobeglitazone by approximately 32% in the fed condition. Although the AUC_last of metformin increased by approximately 70% in the fed condition, there was no effect of food on the C_max of metformin, which is consistent with the already-established food effect on metformin HCl XR. No adverse drug reactions or serious adverse events were observed. This study suggests that CKD-395 0.5/1000 mg exhibits similar exposure and absorption rates to coadministration of single agents and is well tolerated under both fasted and fed conditions.

The Opportunities and Challenges of Peroxisome Proliferator-Activated Receptors Ligands in Clinical Drug Discovery and Development

Peroxisome proliferator-activated receptors (PPARs) are a well-known pharmacological target for the treatment of multiple diseases, including diabetes mellitus, dyslipidemia, cardiovascular diseases and even primary biliary cholangitis, gout, cancer, Alzheimer's disease and ulcerative colitis. The three PPAR isoforms (α, β/δ and γ) have emerged as integrators of glucose and lipid metabolic signaling networks. Typically, PPARα is activated by fibrates, which are commonly used therapeutic agents in the treatment of dyslipidemia. The pharmacological activators of PPARγ include thiazolidinediones (TZDs), which are insulin sensitizers used in the treatment of type 2 diabetes mellitus (T2DM), despite some drawbacks. In this review, we summarize 84 types of PPAR synthetic ligands introduced to date for the treatment of metabolic and other diseases and provide a comprehensive analysis of the current applications and problems of these ligands in clinical drug discovery and development.

Specific Inhibition of the Distribution of Lobeglitazone to the Liver by Atorvastatin in Rats: Evidence for a Rat Organic Anion Transporting Polypeptide 1B2-Mediated Interaction in Hepatic Transport

Cytochrome P450 enzymes and human organic anion transporting polypeptide (OATP) 1B1 are reported to be involved in the pharmacokinetics of lobeglitazone (LB), a new peroxisome proliferator-activated receptor γ agonist. Atorvastatin (ATV), a substrate for CYP3A and human OATP1B1, is likely to be coadministered with LB in patients with the metabolic syndrome. We report herein on a study of potential interactions between LB and ATV in rats. When LB was administered intravenously with ATV, the systemic clearance and volume of distribution at steady state for LB remained unchanged (2.67 ± 0.63 ml/min per kg and 289 ± 20 ml/kg, respectively), compared with that of LB without ATV (2.34 ± 0.37 ml/min per kg and 271 ± 20 ml/kg, respectively). Although the tissue-to-plasma partition coefficient (K_p) of LB was not affected by ATV in most major tissues, the liver K_p for LB was decreased by ATV coadministration. Steady-state liver K_p values for three levels of LB were significantly decreased as a result of ATV coadministration. LB uptake was inhibited by ATV in rat OATP1B2-overexpressing Madin-Darby canine kidney cells and in isolated rat hepatocytes in vitro. After incorporating the kinetic parameters for the in vitro studies into a physiologically based pharmacokinetics model, the characteristics of LB distribution to the liver were consistent with the findings of the in vivo study. It thus appears that the distribution of LB to the liver is mediated by the hepatic uptake of transporters such as rat OATP1B2, and carrier-mediated transport is involved in the liver-specific drug-drug interaction between LB and ATV in vivo.

A Comprehensive Review of Drug-Drug Interactions with Metformin

Metformin is the world's most commonly used oral glucose-lowering drug for type 2 diabetes, and this is mainly because it protects against diabetes-related mortality and all-cause mortality. Although it is an old drug, its mechanism of action has not yet been clarified and its pharmacokinetic pathway is still not fully understood. There is considerable inter-individual variability in the response to metformin, and this has led to many drug-drug interaction (DDI) studies of metformin. In this review, we describe both in vitro and human interaction studies of metformin both as a victim and as a perpetrator. We also clarify the importance of including pharmacodynamic end points in DDI studies of metformin and taking pharmacogenetic variation into account when performing these studies to avoid hidden pitfalls in the interpretation of DDIs with metformin. This evaluation of the literature has revealed holes in our knowledge and given clues as to where future DDI studies should be focused and performed.

Lobeglitazone and pioglitazone as add-ons to metformin for patients with type 2 diabetes: a 24-week, multicentre, randomized, double-blind, parallel-group, active-controlled, phase III clinical trial with a 28-week extension

We aimed to compare the efficacy and safety of lobeglitazone and pioglitazone as add-ons to metformin in patients with type 2 diabetes. Patients who were inadequately controlled by metformin were randomized and treated once daily with either lobeglitazone (0.5 mg, n = 128) or pioglitazone (15 mg, n = 125) for 24 weeks, with a 28-week extension trial of lobeglitazone treatment in patients who consented. The primary endpoint was the change in glycated haemoglobin (HbA1c) concentration from baseline to week 24. At week 24, the mean change from baseline in HbA1c was -0.74% for the lobeglitazone group and -0.74% for the pioglitazone group, with a mean difference of 0.01% [95% confidence interval (CI) of difference, -0.16 to 0.18]. The effects of lobeglitazone on lipid variables and the adverse events associated with lobeglitazone were similar to those observed with pioglitazone. Lobeglitazone was not inferior to pioglitazone as an add-on to metformin in terms of their efficacy and safety.

Efficacy and safety of lobeglitazone monotherapy in patients with type 2 diabetes mellitus over 24-weeks: a multicenter, randomized, double-blind, parallel-group, placebo controlled trial

Objective

The aim of this study was to assess the glucose-lowering and lipid-modifying effects, and safety profile of lobeglitazone, a novel peroxisome proliferator-activated receptor- γ agonist, compared to placebo as a monotherapy in patients with type 2 diabetes.

Research Design and Methods

In this 24-week, multicenter, randomized, double-blind, parallel-group, placebo controlled study, 173 patients were randomly assigned (a 2∶1 ratio) to lobeglitazone 0.5 mg (n = 115) or matching placebo (n = 58) orally once daily. The primary endpoint was the change in glycated hemoglobin (HbA1c) from baseline to the end of treatment. The secondary endpoints included various glycemic parameters, lipid parameters and safety profile (ClinicalTrials.gov number NCT01001611).

Results

At 24 weeks, a significant reduction in HbA1c was observed with lobeglitazone versus placebo (−0.44% vs 0.16%, mean difference −0.6%, p<0.0001). The goal of HbA1c <7% was achieved significantly more in the lobeglitazone group compared to the placebo group (44% vs 12%, p<0.0001). Markers of insulin resistance were also improved in the lobeglitazone group. In addition, lobeglitazone treatment significantly improved triglycerides, high density lipoprotein cholesterol, small dense low density lipoprotein cholesterol, free fatty acid, and apolipoprotein-B/CIII compared to placebo (p<0.01, respectively). More weight gain was observed in the lobeglitazone group than the placebo group (0.89 kg vs – 0.63 kg, mean difference 1.52 kg, p<0.0001). The safety profile was comparable between the two groups and lobeglitazone was well tolerated.

Conclusions

Lobeglitazone 0.5 mg showed a favorable balance in the efficacy and safety profile. The results support a potential role of lobeglitazone in treating type 2 diabetes.

Trial Registration

Clinicaltrials.gov NCT01001611