Physiologically Based Pharmacokinetic Absorption Model for Pexidartinib to Evaluate the Impact of Meal Contents and Intake Timing on Drug Exposure.

Pexidartinib is a systemic treatment for patients with tenosynovial giant cell tumor not amenable to surgery. Oral absorption of pexidartinib is affected by food; administration with a high-fat meal (HFM) or low-fat meal (LFM) increases absorption by approximately 100% and approximately 60%, respectively, compared with the fasted state. Pexidartinib is currently dosed 250 mg orally twice daily with an LFM (approximately 11-14 g of total fat). We developed a physiologically based pharmacokinetic model to determine the impact on drug exposure of dose timing with respect to meals, meal type, and caloric content. A 15%-16% increase in plasma exposure was predicted when consuming an HFM 1 hour after dosing with an LFM, but almost no effect on pharmacokinetics was predicted when an HFM was consumed 3 hours or more before or after pexidartinib dosing with an LFM. Exposure was not significantly affected when pexidartinib was taken with a 500-kcal LFM over the range of fat (approximately 11-14 g of total fat; 20%-25% calories from fat) for an LFM. These findings on timing of pexidartinib dose with respect to meals should be considered by patients and physicians to reduce the potential for side effects.

Exposure-response analysis of the efficacy and safety of esaxerenone, a novel nonsteroidal mineralocorticoid receptor blocker, in hypertensive patients with or without diabetic kidney disease.

BACKGROUND: Esaxerenone is a novel non-steroidal mineralocorticoid receptor blocker. Here, we assessed efficacy and safety exposure-response relationships of esaxerenone and its covariates and thereby justified the recommended dosage regimens, focusing on the safety benefits of up-titration regimen in patients at higher risk for increased serum potassium (sK+). METHODS: The relationships between model-derived individual esaxerenone exposure and efficacy (blood pressure [BP]) and safety (increased sK+) were evaluated using multivariate linear regression and Cox regression analyses, respectively, using data from 1453 hypertensive patients with or without diabetic kidney disease in five clinical studies. RESULTS: Exposure-efficacy analyses demonstrated that higher exposure was linearly associated with greater BP reduction over the investigated dose range. Exposure-safety analyses showed that higher exposure was associated with a higher risk of increased sK+ under a fixed-dosing regimen; higher baseline sK+ and lower baseline estimated glomerular filtration rate (eGFR) were influential covariates. Model-based simulations suggested that fewer occurrences of increased sK+ are expected under the up-titration regimen (from 1.25 to 5 mg) relative to the fixed-dosing regimen (5 mg) in patients with different combinations of these covariates. CONCLUSIONS: The exposure-response analyses supported the esaxerenone recommended doses and the safety benefits of using the up-titration regimen.

Safety, Tolerability, and Pharmacokinetics of Valemetostat Tablets and the Effect of Food on Valemetostat Pharmacokinetics in Healthy Subjects: Two Phase 1 Studies.

Valemetostat is an oral, selective inhibitor of enhancer of zeste homolog-2 (EZH2) and EZH1. In a first-in-human phase-1 trial, valemetostat capsules were well tolerated and clinically active in patients with relapsed/refractory non-Hodgkin lymphoma. Subsequently, a film-coated tablet formulation was developed for future clinical trials and commercialization. We report outcomes from 2 phase 1 trials in healthy Japanese participants, assessing the safety, tolerability, and pharmacokinetics (PK) of valemetostat tablets at single ascending doses (50, 100, and 200-mg), the relative bioavailability between capsules and tablets, and the effect of food (high-fat or low-fat meals) on the PK of valemetostat tablets. In the ascending-dose study, valemetostat maximum plasma concentration (Cmax ) and area under the concentration-time curve (AUC) increased dose-proportionally. Valemetostat plasma PK parameters were similar between the capsule and tablet formulations following a single 200-mg dose. Administration of valemetostat, 200 mg after a meal, was associated with 50%-60% lower Cmax , 30%-50% lower AUC, and a median Tmax delay of 2.5-3 hours relative to fasted administration. Valemetostat was well tolerated in healthy subjects; treatment-emergent adverse events were mild (grade 1) in severity. Based on these trials, the tablet formulation of valemetostat is suitable for use in subsequent clinical trials and should be administered under fasted conditions to avoid a negative food effect.

Effect of itraconazole and fluconazole on the pharmacokinetics of valemetostat: An open-label, phase I study in healthy subjects.

Valemetostat tosylate (valemetostat) is an oral, potent, dual inhibitor of enhancer of zeste homolog (EZH) 2 and EZH1 under investigation for the treatment of cancer, including non-Hodgkin's lymphomas and solid tumors. Itraconazole and fluconazole are antifungal medications often used as typical inhibitors of cytochrome P450 3A (CYP3A [itraconazole and fluconazole]) and P-glycoprotein (P-gp [itraconazole]) in drug-drug interaction studies. Valemetostat is a substrate of CYP3A and P-gp in vitro. This phase I, open-label, single-sequence crossover study (JapicCTI-183902) assessed the pharmacokinetics (PK) of valemetostat when co-administered with itraconazole (a strong CYP3A inhibitor and P-gp inhibitor) or fluconazole (a moderate CYP3A inhibitor) in healthy Japanese male participants 20-45 years of age. Participants were equally allocated to receive two doses of valemetostat 25 mg, once alone and once with either itraconazole or fluconazole (400-mg induction and 200-mg once daily maintenance). Valemetostat PK parameters with versus without itraconazole or fluconazole were compared using analysis of variance models. Overall, 32 participants were enrolled. Co-administration with itraconazole increased valemetostat peak concentration (Cmax ) by 2.9-fold and area under the plasma concentration-time curve extrapolated to infinity (AUCinf ) by 4.2-fold compared with valemetostat alone. When co-administered with fluconazole, the Cmax and AUCinf of valemetostat were each increased by 1.6-fold. No treatment-related or grade ≥3 adverse events were reported. Appropriate valemetostat dose reductions are warranted when used concomitantly with strong CYP3A and P-gp dual inhibitors.

Population pharmacokinetics of esaxerenone, a novel non-steroidal mineralocorticoid receptor blocker, in patients with essential hypertension, patients with diabetic nephropathy, and healthy volunteers.

OBJECTIVES: Esaxerenone is a novel, non-steroidal mineralocorticoid receptor (MR) blocker with improved selectivity and affinity for MR. The objectives of this study were to model the population pharmacokinetics of esaxerenone in a diverse population and to evaluate the effect of covariates on pharmacokinetics parameters. METHODS: A total of 8263 plasma esaxerenone concentrations from 166 healthy volunteers, 1097 hypertensive patients and 360 patients with diabetic nephropathy were pooled. A three-compartment model with sequential zero- and first-order absorption was used to describe the time-courses of plasma esaxerenone following single and multiple doses once daily for up to 12 weeks. Covariate effects were estimated using the full covariate modeling approach. Clinical relevance of covariates was ascertained using tornado plots. RESULTS: Esaxerenone was estimated to have high bioavailability (85.3%), low clearance (3.28 L/h) and relatively large distribution volume at steady state (94.8 L). Body weight (-26 to +36%) and coadministration of itraconazole (+64%) or rifampicin (-68%) were associated with a greater influence on esaxerenone exposure. CONCLUSIONS: The most influential covariates on esaxerenone exposure were coadministrations of itraconazole and rifampicin, followed by body weight. The clinical relevance of effects of renal impairment, mild to moderate hepatic impairment, and age is limited.

Physiologically based pharmacokinetic modelling to predict the clinical effect of CYP3A inhibitors/inducers on esaxerenone pharmacokinetics in healthy subjects and subjects with hepatic impairment.

PURPOSE: Esaxerenone is a novel, oral, nonsteroidal treatment for hypertension. Physiologically based pharmacokinetic (PBPK) modelling was performed to predict the drug-drug interaction (DDI) effect of cytochrome P450 (CYP)3A modulators on esaxerenone pharmacokinetics in healthy subjects and subjects with hepatic impairment. METHODS: In our PBPK model, the fraction of esaxerenone metabolised by CYP3A was estimated from mass-balance data and verified and optimised by clinical DDI study results with strong CYP3A modulators. The model was also verified by the observed pharmacokinetics after multiple oral dosing and by the effect of hepatic impairment on esaxerenone pharmacokinetics. The model was applied to predict the DDI effects on esaxerenone pharmacokinetics with untested CYP3A modulators in healthy subjects and with strong CYP3A modulators in subjects with hepatic impairment. RESULTS: The PBPK model well described esaxerenone pharmacokinetics after multiple oral dosing. The predicted fold changes in esaxerenone plasma exposure after coadministration with strong CYP3A modulators were comparable with the observed data (1.53-fold with itraconazole and 0.31-fold with rifampicin). Predicted DDIs with untested moderate CYP3A modulators were less than the observed DDI with strong CYP3A modulators. The PBPK model also described the effect of hepatic impairment on esaxerenone plasma exposure. The predicted DDI results with strong CYP3A modulators in subjects with hepatic impairment indicate that, for concomitant use of CYP3A modulators, caution is advised for subjects with hepatic impairment, as is for healthy subjects. CONCLUSION: The PBPK model developed predicted esaxerenone pharmacokinetics and DDIs and informed concurrent use of esaxerenone with CYP3A modulators.

Effects of Repeated Oral Administration of Esaxerenone on the Pharmacokinetics of Midazolam in Healthy Japanese Males.

BACKGROUND AND OBJECTIVE: Esaxerenone showed the potential to inhibit and induce activity against cytochrome P450 (CYP) 3A in in vitro studies. We investigated whether repeated administration of 5 mg/day esaxerenone for 14 days influences the pharmacokinetics of midazolam, a sensitive CYP3A substrate, in healthy Japanese males. METHODS: This single-centre, open-label, single-sequence study had two administration periods: period 1: single oral dose of 2 mg midazolam (day 0); period 2: repeated oral doses of 5 mg/day esaxerenone for 14 days, with a single oral dose of 2 mg midazolam on day 14. Full pharmacokinetic profiles of midazolam and 1-hydroxymidazolam on days 0 and 14 and safety data were obtained. Primary pharmacokinetic endpoints for midazolam were area under the plasma concentration-time curve (AUC) from zero to time of the last measurable concentration (AUClast), AUC from zero to infinity (AUCinf), and peak plasma concentration (Cmax). RESULTS: The study included 28 male subjects. One subject was withdrawn because of a mild adverse event (increased hepatic enzyme levels) that resolved without intervention. Repeated administration of esaxerenone increased midazolam AUClast, AUCinf, and Cmax by about 1.2-fold (1.201, 1.201, and 1.224, respectively) compared with administration of midazolam alone. However, repeated administration of esaxerenone did not affect the elimination half-life of midazolam (2.86 versus 2.63 h with and without esaxerenone). There were no safety concerns associated with concomitant administration of esaxerenone and midazolam. CONCLUSIONS: Esaxerenone 5 mg/day had no clinically significant effect on midazolam pharmacokinetics and was not associated with any safety issues. Esaxerenone can be concomitantly administered with drugs of CYP3A substrates without dose adjustments. CLINICAL TRIAL REGISTRATION: JapiCTI-152832.

Quantitative analysis of an impact of P-glycoprotein on edoxaban's disposition using a human physiologically based pharmacokinetic (PBPK) model.

The purpose of this study was to evaluate the impact of P-glycoprotein (P-gp) efflux on edoxaban absorption in gastrointestinal tracts quantitatively by a physiologically based pharmacokinetic (PBPK) model constructed with clinical and non-clinical observations (using GastroPlus™ software). An absorption process was described by the advanced compartmental absorption and transit model with the P-gp function. A human PBPK model was constructed by integrating the clinical and non-clinical observations. The constructed model was demonstrated to reproduce the data observed in the mass-balance study. Thus, elimination pathways can be quantitatively incorporated into the model. A constructed model successfully described the difference in slopes of plasma concentration (Cp)-time curve at around 8 - 24 hr post-dose between intravenous infusion and oral administration. Furthermore, the model without P-gp efflux activity can reproduce the Cp-time profile in the absence of P-gp activity observed from the clinical DDI study results. Since the difference of slopes between intravenous infusion and oral administration also disappeared by the absence of P-gp efflux activity, P-gp must be a key molecule to govern edoxaban's PK behavior. The constructed PBPK model will help us to understand the significant contribution of P-gp in edoxaban's disposition in gastrointestinal tracts quantitatively.

Nrf2 Lowers the Risk of Lung Injury via Modulating the Airway Innate Immune Response Induced by Diesel Exhaust in Mice.

In the present study, we investigated the role of Nrf2 in airway immune responses induced by diesel exhaust (DE) inhalation in mice. C57BL/6J Nrf2+/+ and Nrf2-/- mice were exposed to DE or clean air for 8 h/day and 6 days/week for 4 weeks. After DE exposure, the number of neutrophils and macrophage inflammatory protein (MIP)-2 level in bronchoalveolar lavage fluid (BALF) and interleukin (IL)-17 level in the lung tissue increased in Nrf2-/- mice compared with Nrf2+/+ mice; however, the lack of an increase in the level of tumor necrosis factor (TNF)-α in the lung tissue in Nrf2+/+ mice and mild suppression of the level of TNF-α in Nrf2-/- mice were observed; the level of granulocyte macrophage colony-stimulating factor (GM-CSF) in the lung tissue decreased in Nrf2-/- mice than in Nrf2+/+ mice; the number of DE particle-laden alveolar macrophages in BALF were larger in Nrf2-/- mice than in Nrf2+/+ mice. The results of electron microscope observations showed alveolar type II cell injury and degeneration of the lamellar body after DE exposure in Nrf2-/- mice. Antioxidant enzyme NAD(P)H quinone dehydrogenase (NQO)1 mRNA expression level was higher in Nrf2+/+ mice than in Nrf2-/- mice after DE exposure. Our results suggested that Nrf2 reduces the risk of pulmonary disease via modulating the airway innate immune response caused by DE in mice.

Pharmacokinetic interactions of esaxerenone with amlodipine and digoxin in healthy Japanese subjects.

BACKGROUND: To investigate the effects of coadministration of esaxerenone with amlodipine on the pharmacokinetics (PK) of each drug, and of esaxerenone on the PK of digoxin. METHODS: In three open-label, single-sequence, crossover studies, healthy Japanese males received single oral doses of esaxerenone 2.5 mg (Days 1, 15), with amlodipine 10 mg/day (Days 8-18) (Study 1, N = 24); single doses of amlodipine 2.5 mg (Days 1, 21), with esaxerenone 5 mg/day (Days 8-25) (Study 2; N = 20); or digoxin 0.25 mg/day (Days 1-15) with esaxerenone 5 mg/day (Days 11-15) (Study 3; N = 20). PK parameters and safety were assessed. RESULTS: Study 1: esaxerenone peak plasma concentration (Cmax) and time to Cmax were unaltered by amlodipine coadministration, but mean half-life was slightly prolonged from 18.5 to 20.9 h. Geometric least-squares mean (GLSM) ratios for Cmax, area under the plasma concentration-time curve (AUC) from zero to last measurable concentration and from zero to infinity for esaxerenone + amlodipine versus esaxerenone were 0.958, 1.154, and 1.173, respectively. Study 2: corresponding GLSM ratios for amlodipine + esaxerenone versus amlodipine were 1.099, 1.185, and 1.214. Study 3: esaxerenone did not markedly alter digoxin PK. GLSM ratios for Cmax, trough plasma concentration, and AUC during a dosing interval for digoxin versus esaxerenone + digoxin were 1.130, 1.088, and 1.072, respectively. CONCLUSIONS: No drug-drug interactions are expected during combination therapy with esaxerenone and either amlodipine or digoxin, based on a lack of any clinically relevant PK changes. TRIAL REGISTRATION: Studies 1 and 2: JapicCTI-163379 (registered on 20 September 2016); Study 3: JapicCTI-163443 (registered on 24 November 2016).

Effects of itraconazole and rifampicin on the single-dose pharmacokinetics of the nonsteroidal mineralocorticoid receptor blocker esaxerenone in healthy Japanese subjects.

AIMS: To investigate the effects of the strong cytochrome P450 (CYP) 3A inhibitor itraconazole and the strong CYP3A inducer rifampicin on the pharmacokinetics of single-dose esaxerenone, a nonsteroidal mineralocorticoid receptor blocker, in healthy Japanese subjects. METHODS: Two open-label, single-sequence, crossover studies were conducted in healthy Japanese males aged 20-45 years. In Study 1 (n = 20), subjects received a single oral 2.5 mg dose of esaxerenone (Days 1, 13), with itraconazole 200 mg twice daily (Day 8) and once daily (Days 9-16). In Study 2 (n = 12), subjects received a single oral 5 mg dose of esaxerenone (Days 1, 13), with rifampicin 600 mg once daily (Days 8-16). The plasma concentration of esaxerenone and esaxerenone metabolites were measured using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were calculated using noncompartmental analysis, and safety was assessed. RESULTS: Esaxerenone exposure increased when coadministered with itraconazole. Geometric least-square mean ratios (90% confidence interval) of peak plasma esaxerenone concentration (Cmax ), area under the plasma concentration-time curve (AUC) from zero until the last measurable concentration (AUClast ) and AUC from zero until infinity (AUCinf ) were 1.13 (1.05, 1.20) ng mL-1 , 1.47 (1.40, 1.54) ng h mL-1 and 1.53 (1.45, 1.62) ng h mL-1 , respectively. Esaxerenone exposure decreased when coadministered with rifampicin. Geometric least-squares mean ratios (90% confidence interval) of esaxerenone Cmax , AUClast and AUCinf were 0.659 (0.599, 0.724), 0.315 (0.300, 0.332) and 0.312 (0.297, 0.328), respectively. CONCLUSION: Itraconazole increased esaxerenone AUCinf by 53.1%, and rifampicin decreased esaxerenone AUCinf by 68.8%. These results suggest that caution is recommended when coadministering esaxerenone with strong inhibitors and inducers of CYP3A.

Randomized, Double-Blind, Single-Dose, Placebo-Controlled Crossover Study to Evaluate the Effects of Esaxerenone on QTc Interval in Healthy Subjects.

This phase 1 single-center, single-dose, double-dummy, placebo-controlled, 4-period and 4-sequence crossover study assessed the potential of esaxerenone, a novel nonsteroidal mineralocorticoid receptor blocker used to treat hypertension, to affect cardiac repolarization. In this double-blind study, 55 subjects were randomized to single doses of 10 mg esaxerenone (therapeutic dose), 40 mg esaxerenone (supratherapeutic dose), 400 mg moxifloxacin, or placebo. Serial electrocardiograms and pharmacokinetics (PK) were obtained over 24 and 168 hours, respectively. The primary end point was Fridericia-corrected QT interval (QTcF). Secondary end points included safety and PK. Assay sensitivity was confirmed as the lower limit of 90% confidence interval (90%CIs) for placebo-corrected change from baseline QTcF (∆∆QTcF) for moxifloxacin was >5 milliseconds at the prespecified times; mean ∆∆QTcF was 12.5 milliseconds at 3 and 4 hours postdose. The upper 90%CI limits of ∆∆QTcF were ≤0 milliseconds at all times for both doses of esaxerenone. No concentration-QTc relationship was identified. Therefore, esaxerenone had no potential to inhibit cardiac repolarization. No deaths or serious adverse events (AEs) occurred; 1 subject discontinued the study because of a treatment-emergent AE unrelated to esaxerenone. This clinical evaluation showed that esaxerenone has no QTc prolongation potential.

Pharmacokinetics and Safety of Single-Dose Esaxerenone in Japanese Subjects with Mild to Moderate Hepatic Impairment.

INTRODUCTION: The mineralocorticoid receptor (MR) blocker esaxerenone is a new treatment for hypertension in Japan and under development for treatment of diabetic nephropathy. Hepatic impairment is known to impact the pharmacokinetics (PKs) of other MR blocking drugs. The aim of the present study was to characterise the PKs and safety of a single oral dose of esaxerenone in Japanese subjects with mild-moderate hepatic impairment. METHODS: In this open-label, parallel-group study, subjects with mild (Child-Pugh grade A) or moderate (grade B) hepatic impairment, and healthy controls with normal hepatic function matched by age and BMI (all groups n = 6), received a single 2.5-mg oral dose of esaxerenone. Plasma concentrations were measured by liquid chromatography-tandem mass spectrometry, and PK parameters were calculated using non-compartmental analysis. RESULTS: Geometric least-squares mean (GLSM) ratios (90% confidence intervals [CIs]) for area under the plasma concentration-time curve (up to the last quantifiable time, up to infinity) in subjects with mild hepatic impairment versus normal hepatic function were 0.837 (0.637, 1.099) and 0.824 (0.622, 1.092), respectively. Corresponding values for moderate hepatic impairment versus normal hepatic function were 1.078 (0.820, 1.415) and 1.098 (0.829, 1.454). GLSM ratios (90% CIs) for peak plasma concentration (Cmax) were 0.959 (0.778, 1.182) for mild hepatic impairment versus normal hepatic function and 0.804 (0.653, 0.992) for moderate hepatic impairment versus normal hepatic function. Time to Cmax and clearance values were comparable between groups. The incidence of adverse events (AEs) was 16.7% in the moderate hepatic impairment and normal hepatic function groups. One serious AE (hepatic encephalopathy) occurred in one subject with moderate hepatic impairment. CONCLUSIONS: Mild to moderate hepatic impairment had no clinically relevant effect on esaxerenone exposure. Esaxerenone dosage adjustment based on PKs is unlikely to be needed in patients with mild to moderate hepatic impairment. TRIAL REGISTRATION: JapicCTI-163339. FUNDING: Daiichi Sankyo Co., Ltd.

Absolute Bioavailability of Esaxerenone and Food Effects on its Pharmacokinetics After a Single Oral Dose in Healthy Japanese Subjects: An Open-Label Crossover Study.

INTRODUCTION: To investigate the absolute bioavailability of esaxerenone and the effects of food on its pharmacokinetics (PK) after a single oral dose in healthy Japanese subjects. METHODS: Twenty-four Japanese males aged 20-45 years were randomised to six groups (each n = 4) in this single-centre, open-label, three-way, three-period crossover study. Esaxerenone (5 mg) was administered in the fasting state as a single oral dose, single intravenous infusion over 1 h, or in the postprandial state as a single oral dose. Plasma samples were taken before and during the 96 h after drug administration. Drug concentrations were measured using liquid chromatography-tandem mass spectrometry. PK parameters were calculated using noncompartmental analysis, and safety was assessed. RESULTS: After fasting intravenous administration, total body clearance was 3.69 L h-1 and volume of distribution was 92.7 L. The plasma concentration-time profile of esaxerenone was similar after fasting and postprandial administration. Absolute bioavailability of a single oral 5-mg dose of esaxerenone was 89.0% in the fasting state and 90.8% postprandially. Point estimates (1.010 and 1.019, respectively) and 90% confidence intervals for geometric least squares mean peak plasma concentrations and area under the plasma concentration-time curve ratios after postprandial versus fasting oral esaxerenone were within the prespecified range (0.80, 1.25). No severe adverse events occurred throughout the study. CONCLUSIONS: Esaxerenone has a high absolute bioavailability of approximately 90% and food has no effect on esaxerenone PK after a single oral dose of 5 mg in healthy Japanese subjects. Additionally, no safety concerns were identified. CLINICAL TRIAL REGISTRATION: JapicCTI No. 163452. FUNDING: Daiichi Sankyo Co., Ltd.

Incidence of metachronous gastric cancer in patients whose primary gastric neoplasms were discovered after Helicobacter pylori eradication.

BACKGROUND AND AIMS: The incidence of metachronous gastric cancer (MGC) in patients whose primary gastric neoplasm is discovered after Helicobacter pylori eradication remains unclear. Here, we evaluated the long-term effect of previous H pylori eradication on development of MGC after endoscopic submucosal dissection (ESD). METHODS: We analyzed prospectively collected data of consecutive patients with successful H pylori eradication more than 1 year before (eradicated group, 180 patients) or after (control group, 602 patients) initial curative ESD. These patients were also followed by endoscopy for over 2 years. Propensity score matching and inverse probability of treatment weighting (IPTW) were used to adjust for confounding variables during data analysis. The main outcome was the incidence of MGC after initial ESD. RESULTS: In a propensity-matched analysis of 174 pairs, the incidence of MGC was similar in the 2 cohorts (33.9 per 1000 person-years vs 40.8 per 1000 person-years in the control group, P = .454) at a median follow-up of 4.1 years (interquartile range, 3.0-5.6). Incidences were also similar in the 2 groups when data were analyzed using IPTW, even after exclusion of 123 patients with successful H pylori eradication <5 years before initial ESD. Multiple Cox regression analysis revealed age, differentiated-type histology, and initial multiplicity were predictors of MGC in patients after initial curative ESD. CONCLUSIONS: The frequency of follow-up surveillance after initial curative ESD should be kept constant, irrespective of whether H pylori eradication is performed before or after initial curative ESD.

Pharmacokinetics, Metabolism, and Excretion of [14C]Esaxerenone, a Novel Mineralocorticoid Receptor Blocker in Humans.

Esaxerenone (CS-3150) is a novel, nonsteroidal, selective mineralocorticoid receptor blocker. The absorption, metabolism, distribution, and excretion of esaxerenone were assessed in in vitro studies and in a clinical study, where [14C]esaxerenone (150 µCi/20 mg) was administered orally to six healthy male subjects. The plasma concentrations of esaxerenone and its metabolites (M4, M11, and M1) were measured using liquid chromatography-tandem mass spectrometry. The recovery of radioactivity was 92.5%, with 38.5% and 54.0% excreted in the urine and feces, respectively. The half-life of radioactivity in blood and plasma was approximately 30 hours, similar to that of the unchanged form in plasma. The blood-to-plasma ratio was 0.628, demonstrating low partitioning to blood components. In plasma, esaxerenone was the most abundant moiety (40.8%), followed by O-glucuronide (21.4%; M4), acyl-glucuronide of amide-bond hydrolysate (8.0%; M11), and the deshydroxyethyl form (1.7%; M1). In vitro studies showed that esaxerenone was a substrate of CYP3A and multiple UDP-glucuronosyltransferase isoforms. Oxidation contributed approximately 30% to its clearance, as indicated by the excretion ratio of oxidized metabolites into urine and feces. Caco-2 studies showed that esaxerenone was a substrate of P-glycoprotein and breast cancer resistance protein; however, the excretion ratios of the unchanged form in the feces and urine were 18.7% and 1.6%, respectively, indicating that these transporters were not important for the absorption and elimination of esaxerenone. Low urinary excretion of esaxerenone suggested that the plasma exposure of esaxerenone was not affected by renal dysfunction. Multiple elimination pathways including oxidation, glucuronidation, and hydrolysis, and the low contribution of transporters, indicated limited drug-drug interaction potential.

Single- and multiple-dose escalation study to assess pharmacokinetics, pharmacodynamics and safety of oral esaxerenone in healthy Japanese subjects.

AIMS: To characterize the pharmacokinetics, pharmacodynamics and safety of esaxerenone, a mineralocorticoid receptor antagonist, in healthy adult Japanese men. METHODS: Double-blind, placebo-controlled, sequential, dose-escalation studies were conducted in subjects randomized to receive oral once-daily esaxerenone (ranges: 5-200 mg [single-dose]; 10-100 mg over 10 days [multiple-dose]) or placebo under fasting conditions. Plasma concentrations were analysed by liquid chromatograph-tandem mass spectrometry. Pharmacokinetic parameters were determined by noncompartment analysis. Plasma/urine levels of pharmacodynamic biomarkers for mineralocorticoid receptor activity were evaluated. RESULTS: In total, 48/48 and 39/40 subjects completed the single- and multiple-dose studies, respectively. Exposures were generally dose-proportional. The tmax , t1/2 and CL/F remained unchanged, independent of dose; the respective ranges were 1.5-4.0 h, 22.3-25.1 h, and 4.0-5.2 l h-1 (multiple-dose study). Vz /F ranged from 136.5 to 283.7 l in the multiple-dose study, and exposure reached steady state by day 4. The mean observed accumulation ratio, by dose, ranged from 1.36-1.98. The urinary Na+ /K+ ratio increased after single-dose administration; however, its relationship to the doses tested remains unclear. Plasma renin activity, active renin concentration and aldosterone concentration increased dose-dependently. Although blood potassium levels increased dose-dependently in the multiple-dose study (reaching a maximum mean ± standard deviation of 4.63 ± 0.354 mmol l-1 in the 100-mg group), no safety/tolerability-related problems were detected in either study. CONCLUSIONS: Exposure levels in healthy adults receiving esaxerenone were generally dose-proportional. Dose-dependent changes in plasma pharmacodynamic biomarkers for the mineralocorticoid receptor were identified during multiple-dose treatment and support the pharmacological activity of esaxerenone. No important safety concerns were identified.