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.

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.

DS-5670a, a novel mRNA-encapsulated lipid nanoparticle vaccine against severe acute respiratory syndrome coronavirus 2: Results from a phase 2 clinical study.

BACKGROUND: DS-5670a is a vaccine candidate for coronavirus disease 2019 (COVID-19) harnessing a novel modality composed of messenger ribonucleic acid (mRNA) encoding the receptor-binding domain (RBD) from the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) encapsulated in lipid nanoparticles. Here, we report the safety, immunogenicity, and pharmacokinetic profile of DS-5670a from a phase 2 clinical trial in healthy adults who were immunologically naïve to SARS-CoV-2. METHODS: The study consisted of an open-label, uncontrolled, dose-escalation part and a double-blind, randomized, uncontrolled, 2-arm, parallel-group part. A total of 80 Japanese participants were assigned to receive intramuscular DS-5670a, containing either 30 or 60 µg of mRNA, as two injections administered 4 weeks apart. Safety was assessed by characterization of treatment-emergent adverse events (TEAEs). Immunogenicity was assessed by neutralization titers against SARS-CoV-2, anti-RBD immunoglobulin (Ig)G levels, and SARS-CoV-2 spike-specific T cell responses. Plasma pharmacokinetic parameters of DS-5670a were also evaluated. RESULTS: Most solicited TEAEs were mild or moderate with both the 30 and 60 µg mRNA doses. Four participants (10 %) in the 60 µg mRNA group developed severe redness at the injection site, but all cases resolved without treatment. There were no serious TEAEs and no TEAEs leading to discontinuation. Humoral immune responses in both dose groups were greater than those observed in human convalescent serum; the 60 µg mRNA dose produced better responses. Neutralization titers were found to be correlated with anti-RBD IgG levels (specifically IgG1). DS-5670a elicited antigen-specific T helper 1-polarized cellular immune responses. CONCLUSIONS: The novel mRNA-based vaccine candidate DS-5670a provided favorable immune responses against SARS-CoV-2 with a clinically acceptable safety profile. Confirmatory trials are currently ongoing to evaluate the safety and immunogenicity of DS-5670a as the primary vaccine and to assess the immunogenicity when administered as a heterologous or homologous booster. TRIAL REGISTRY: https://jrct.niph.go.jp/latest-detail/jRCT2071210086.

Trastuzumab Deruxtecan Dosing in Human Epidermal Growth Factor Receptor 2-Positive Gastric Cancer: Population Pharmacokinetic Modeling and Exposure-Response Analysis.

This study evaluated the benefit/risk of trastuzumab deruxtecan (T-DXd) 6.4 mg/kg in patients with human epidermal growth factor receptor 2 (HER2)-positive gastric cancer using pharmacometrics. A population pharmacokinetic (PopPK) model was developed using data from patients with gastric cancer, breast cancer, or other tumors in T-DXd clinical trials, primarily conducted in Asia. Post hoc model-estimated pharmacokinetic metrics were used in exposure-efficacy (objective response rates, ORRs) and exposure-safety analyses. The PopPK analysis included 808 patients (217 with gastric cancer, 512 with breast cancer, and 79 with other cancers). In gastric cancer, the T-DXd 6.4 mg/kg steady-state exposure metrics were lower compared with 6.4 mg/kg in breast cancer, but were similar to 5.4 mg/kg in breast cancer. Tumor type was selected as a significant covariate on T-DXd clearance. In exposure-efficacy analysis among 160 patients with gastric cancer, the T-DXd steady-state minimum concentration was associated with a confirmed ORR in univariate logistic regression analysis (P = .023). The model-predicted confirmed ORRs in gastric cancer were 36.0% (90%CI 29.3% to 43.7%) with 5.4 mg/kg and 40.0% (90%CI 33.1% to 47.6%) with 6.4 mg/kg. Among 808 patients in the exposure-safety analyses, the model-predicted estimates for the rates of any-grade interstitial lung disease (ILD) over a period of 180 days were 10.2% (90%CI 8.7% to 12.8%) with 6.4 mg/kg in gastric cancer and 9.7% (90%CI 8.2% to 11.8%) with 5.4 mg/kg in breast cancer. In gastric cancer, the efficacy of T-DXd was higher at 6.4 mg/kg than at 5.4 mg/kg. Exposure and ILD rates were comparable between 6.4 mg/kg in gastric cancer and 5.4 mg/kg in breast cancer. This study identified T-DXd 6.4 mg/kg as the recommended dose in HER2-positive gastric cancer.

Pharmacokinetics and Bioequivalence of Mirogabalin Orally Disintegrating Tablets and Conventional Tablets in Healthy Japanese Participants.

This single-center, randomized, open-label, single-dose, 2-group, 2-stage crossover trial evaluated the bioequivalence of 15 mg of mirogabalin as orally disintegrating tablets (ODTs) with conventional mirogabalin tablets in healthy Japanese men. The trial involved two studies: in Study 1, the ODT formulation was taken without water, and in Study 2, the ODT formulation was taken with water. The conventional tablet was taken with water in both studies. We investigated the pharmacokinetic parameters and bioequivalence of the 2 formulations, including the maximum plasma concentration and the area under the plasma concentration-time curve up to the last quantifiable time. The plasma concentrations of mirogabalin were determined by a validated liquid chromatography with tandem mass spectrometry method. A total of 72 participants were enrolled and completed the trial. The geometric least-squares mean ratios of maximum plasma concentration of the ODT formulation to the conventional formulation were within the prespecified bioequivalence range of 0.80-1.25 (Study 1, 0.995; Study 2, 1.009), as was the area under the plasma concentration-time curve up to the last quantifiable time (Study 1, 1.023; Study 2, 1.035). No serious adverse events were observed. In conclusion, mirogabalin 15-mg ODTs, either with or without water, were bioequivalent to conventional 15-mg tablets.

Population Pharmacokinetics of Trastuzumab Deruxtecan in Patients With HER2-Positive Breast Cancer and Other Solid Tumors.

Trastuzumab deruxtecan (DS-8201) is a human epidermal growth factor receptor 2 (HER2)-targeting antibody-drug conjugate with a novel enzyme-cleavable linker, a topoisomerase I inhibitor payload, and a drug-to-antibody ratio of ≈ 8. We have characterized the population pharmacokinetics (PK) of trastuzumab deruxtecan and released drug (topoisomerase I inhibitor) in patients with HER2-positive breast cancer or other solid tumor malignancies. This analysis includes pooled data from five clinical studies with 639 patients. Trastuzumab deruxtecan doses ranged from 0.8 to 8.0 mg/kg every 3 weeks. Serum concentrations of trastuzumab deruxtecan and released drug were analyzed using a sequential two-step approach, with the nonlinear mixed-effects modeling methods. Covariate assessment was based upon stepwise forward-addition and backward-elimination process, followed by both univariate and multivariate analysis quantifying their impact on steady-state exposure of trastuzumab deruxtecan and released drug. A two-compartment model with linear elimination best described PK profiles of intact trastuzumab deruxtecan, while a one-compartment model with time-varying release-rate constant and linear elimination described released-drug PK profiles. Statistically significant covariates (country, tumor size, sex, formulation, age, body weight, albumin, total bilirubin, and aspartate aminotransferase) resulted in < 20% change in steady-state area under the concentration-time curve of trastuzumab deruxtecan and released drug, except for increased body weight (95th percentile, 86 kg) and decreased albumin (5th percentile, 31 g/L). Analysis of patients stratified by country, race, renal function, and hepatic function found no clinically meaningful differences in steady-state exposure of intact trastuzumab deruxtecan or released drug. Overall, results suggest that no dose adjustment based on tested covariates or in specific patient populations is warranted.

Safety and Pharmacokinetics of DS-8500a, a Novel GPR119 Agonist, After Multiple Oral Doses in Healthy Japanese Males.

BACKGROUND AND OBJECTIVES: G protein-coupled receptor 119 (GPR119) agonists reduce plasma glucose by promoting insulin secretion in a glucose-dependent manner. We evaluated the safety and pharmacokinetics of multiple oral doses of DS-8500a, a GPR119 agonist, under fed conditions in healthy adult Japanese male subjects. METHODS: In this Phase 1, randomized, placebo-controlled, double-blind, multiple oral dose study, participants were aged ≥ 20 and ≤ 45 years with a body mass index ≥ 18.5 and < 25.0 kg/m2. DS-8500a 50 and 100 mg or placebo were administered orally, once daily, 30 min after breakfast for 7 days. The primary endpoints were pharmacokinetics and safety. RESULTS: Twenty-four subjects were included (6, 9, and 9 in the placebo, 50-, and 100-mg groups, respectively). On Day 7, the mean maximum plasma concentration (Cmax) was 812 ng/mL in the 50-mg group and 1310 ng/mL in the 100-mg group. The mean area under the plasma concentration-time curve during dosing interval (AUCtau) was 7910 and 13,200 ng·h/mL in the two treatment groups, respectively. The observed accumulation ratio was 1.25 in the 50-mg group and 1.32 in the 100-mg group. All adverse events were mild and judged unrelated to the study drug. CONCLUSIONS: DS-8500a plasma concentrations reached steady state from Day 3, and Cmax and AUCtau increased in a less than dose-proportional manner. After repeated doses of DS-8500a at 100 mg, the DS-8500a trough concentration was expected to reach a pharmacologically active dose. DS-8500a was well tolerated up to 100 mg after a 7-day administration. STUDY REGISTRY IDENTIFICATION: JAPIC ID: JapicCTI-173550 (registered retrospectively on 30 March 2017).

Population Pharmacokinetics of Edoxaban in Japanese Atrial Fibrillation Patients With Severe Renal Impairment.

This is a population pharmacokinetic (PopPK) analysis to predict PK of edoxaban, a direct-acting oral anticoagulant, in nonvalvular atrial fibrillation (NVAF) patients with severe renal impairment (SRI; creatinine clearance [CLcr ] <30 mL/min). Data from a phase 3 study recently conducted in Japanese NVAF patients (n = 90), including patients with SRI, were used to update the ENGAGE PopPK model that had been developed based on pooled data from the phase 3 ENGAGE AF-TIMI 48 study and 13 phase 1 PK studies, which included few patients with SRI. The final model indicated that the ENGAGE PopPK model was applicable to Japanese patients in that the model-simulated and study-observed concentration-time profiles were in agreement. Estimated model parameters after the addition of Japanese SRI data were consistent with those derived from the original ENGAGE PopPK data set. The model-predicted exposure in NVAF patients with SRI who received edoxaban at a 15-mg, once-daily dose was similar to that in patients with normal renal function or with mild renal impairment receiving a 30-mg dose. This suggests that efficacy and safety data from the ENGAGE AF study can be used to support dose setting for NVAF patients with SRI.

Population pharmacokinetics of laninamivir and its prodrug laninamivir octanoate in healthy subjects and in adult and pediatric patients with influenza virus infection.

Laninamivir octanoate (LO) is a new neuraminidase inhibitor for inhalation. The objectives of this study were to model the population pharmacokinetics of LO and its active metabolite laninamivir after inhaled administration of LO using a pooled population of healthy subjects, and adult and pediatric patients with influenza virus infection from 8 clinical studies, and to evaluate covariate effects on pharmacokinetics. The pharmacokinetics of LO and laninamivir in plasma and urine are well-described by structural models that consist of a 2-compartment model for LO with instantaneous bolus input and first-order elimination; and a 1-compartment model for laninamivir with formation of laninamivir via the metabolic pathway from LO in systemic circulation, entry of laninamivir from the respiratory tract compartment, and linear elimination. Creatinine clearance was identified as a covariate of apparent total clearance for LO and renal clearances for LO and laninamivir, with the largest effect on laninamivir exposure. Body weight was identified to affect distribution volumes of LO and laninamivir and the metabolic clearance of LO; however there was no notable effect on exposures across the wide body weight range evaluated. The population pharmacokinetic model also provides insight into the likely kinetics of drug disposition in the respiratory tract following inhaled administration.

Association study of genetic polymorphisms of drug transporters, SLCO1B1, SLCO1B3 and ABCC2, in African-Americans, Hispanics and Caucasians and olmesartan exposure.

It has been reported that organic anion-transporting polypeptide (OATP) 1B1, OATP1B3 and multidrug resistance-associated protein 2 are involved in the hepatobiliary transport of olmesartan. We investigated the association of SLCO1B1, SLCO1B3 and ABCC2 polymorphisms with the pharmacokinetics of olmesartan. We sequenced all exons, exon-intron junctions and the 5' and 3' flanking regions of the three genes in 115 individuals from African-American, Hispanic and Caucasian populations who had participated in our clinical studies. A total of 348 single-nucleotide polymorphisms (SNPs) were identified with a minor allele frequency of ≥0.01 in at least one population; 132 SNPs were detected in SLCO1B1, 130 in SLCO1B3 and 86 in ABCC2. We characterized the linkage disequilibrium (LD) and haplotypes shared across the populations and then evaluated the association between the haplotypes and the pharmacokinetics of olmesartan. Seven inter-ethnic LD blocks were observed in SLCO1B1, while three in SLCO1B3 and four in ABCC2. Although extensive variability in the sequences of SLCO1B1, SLCO1B3 and ABCC2 existed across the three populations, there was no remarkable difference in any pharmacokinetic parameters of olmesartan between subjects with and without any major haplotypes in the three transporter genes we tested.

Assessment of the effects of renal impairment on the pharmacokinetic profile of laninamivir, a novel neuraminidase inhibitor, after a single inhaled dose of its Prodrug, CS-8958.

This open-label, single-dose study assessed the safety and pharmacokinetics of laninamivir, a new long-acting neuraminidase inhibitor, after an inhaled 20-mg dose of its prodrug, CS-8958, to a total of 20 subjects with normal, mild, moderate, or severe renal impairment. CS-8958 and laninamivir concentrations were measured in plasma and urine by validated liquid chromatography tandem mass spectrometry methods. The area under the concentration-time curve extrapolated to infinity (AUC(0-inf)), maximum concentration (C(max)), and time to C(max) of CS-8958 did not change with the degree of renal impairment, whereas the half-life (t(1/2)) of CS-8958 increased with increasing renal insufficiency. The AUC(0-inf) and C(max) of laninamivir tended to increase along with the decrease of creatinine clearance. The AUC(0-inf) of laninamivir compared with normal subjects increased 1.10-, 2.03-, and 4.92-fold in subjects with mild, moderate, and severe renal impairment, respectively, without changing t(1/2) among the subjects. Renal clearance of both CS-8958 and laninamivir was well correlated with creatinine clearance. These data indicate that the rate-limiting step for the elimination of laninamivir would not be the renal excretion rate but rather the drug release rate to plasma from the retained tissues. CS-8958 was well tolerated by all the subjects, although increasing renal dysfunction leads to increasing systemic exposure to laninamivir, particularly in severe renal insufficiency.

Clinical pharmacokinetics of laninamivir, a novel long-acting neuraminidase inhibitor, after single and multiple inhaled doses of its prodrug, CS-8958, in healthy male volunteers.

Phase 1 studies of laninamivir, a novel long-acting neuraminidase inhibitor, were carried out to assess its safety, tolerability, and pharmacokinetics after inhaled administration of its prodrug, CS-8958. Healthy male volunteers (total N = 76) participated in double-blind, randomized, placebo-controlled trials and received 5, 10, 20, 40, 80, or 120 mg of a single dose or 20 or 40 mg of a twice-daily dose for 3 days. The clinical and laboratory parameters and plasma and urinary concentrations of CS-8958 and laninamivir for 144 hours post dosing were measured. There were no adverse events related to the test drug. CS-8958 disappeared from plasma with a half-life of about 2 hours, although laninamivir was slowly eliminated from the body, lasting for even up to 144 hours after administration with a half-life of about 3 days. Area under the curve and maximum concentration increased almost linearly with the dose administered. The cumulative urinary excretion amounts of CS-8958 and laninamivir were 2.3% to 3.6% and 10.7% to 14.6% of the dose, respectively. The half-life of the urinary excretion rates of laninamivir at higher single dose is comparable to plasma half-life. CS-8958, when inhaled by healthy volunteers, is well tolerated and exhibits a suitable pharmacokinetic profile, suggesting potential for long-lasting anti-influenza activity.

Comparative pharmacodynamics of olmesartan and azelnidipine in patients with hypertension: a population pharmacokinetic/pharmacodynamic analysis.

SUMMARY: The objectives of this study were to identify the factors influencing antihypertensive response to the angiotensin receptor blocker, olmesartan medoxomil, or the calcium channel blocker, azelnidipine, and to discuss the possibility of utilizing them as predictors for drug selection prior to therapy. A two-way crossover study of olmesartan medoxomil and azelnidipine was conducted in 29 patients with mild to moderate essential hypertension. The 24-hour ambulatory blood pressure measurements (ABPM) and plasma drug concentrations were obtained on the first and at the end of each treatment period, and were analyzed using population pharmacokinetic/pharmacodynamic (PK/PD) modeling approach. The population PK/PD models considering circadian variations in baseline blood pressure well described the observed plasma drug concentrations and 24-hour ABPM profiles. Pre-treatment plasma renin activity (PRA) was identified as a significant covariate on the maximum drug effect (E(max)) of olmesartan, whereas azelnidpine E(max) was independent of patient background characteristics investigated. No patient was found to have a high E(max) to one agent who also had a high E(max) to the other. In conclusion, the effects of olmesartan medoxomil and azelnidipine were modestly correlated with pharmacokinetic profiles, and the pre-treatment PRA level could be a useful determinant of responsiveness in selecting olmesartan medoxomil and azelnidipine.

Population pharmacokinetics of olmesartan following oral administration of its prodrug, olmesartan medoxomil: in healthy volunteers and hypertensive patients.

BACKGROUND: Olmesartan medoxomil (CS-866) is a new orally active angiotensin II receptor antagonist that is highly selective for the AT1 receptor subtype. OBJECTIVE: To develop a population pharmacokinetic model for olmesartan (RNH-6270), the active metabolite of olmesartan medoxomil, in healthy volunteers and hypertensive patients, and to evaluate effects of covariates on the apparent oral clearance (CL/F), with particular emphasis on the effect of race. DESIGN: Retrospective analysis of data from 12 phase I-III trials in the US, Europe and Japan. PARTICIPANTS: Eighty-nine healthy volunteers and 383 hypertensive patients. METHODS: Nonlinear mixed-effects modelling was used to evaluate 7911 olmesartan plasma sample concentrations. The covariates included age, bodyweight, sex, race (Westerners [including Caucasians and Hispanics] versus Japanese), patient status (hypertensive patients versus healthy volunteers), serum creatinine level as an index of renal function and serum chemistry data as indices of hepatic function. RESULTS: The pharmacokinetic data of olmesartan were well described by a two-compartment linear model with first-order absorption and an absorption lag-time, parameterised in terms of CL/F (6.66 L/h for a typical male Western hypertensive patient), absorption rate constant (1.46h-1), elimination rate constant (0.193h-1), rate constant from the central to peripheral compartment (0.061h-1), rate constant from the peripheral to central compartment (0.079h-1) and absorption lag-time (0.427h). Analysis of covariates showed that age, bodyweight, sex, patient status and renal function were factors influencing the clearance of olmesartan. CONCLUSION: The population pharmacokinetic analysis of olmesartan showed that: (i) severe renal impairment (serum creatinine >265 micromol/L [approximately 3 mg/dL]) could cause a clearance decrease of > or =30%; (ii) older age, lower bodyweight and being female were determinants of lower clearance but their effects on olmesartan clearance were within 20%; (iii) no statistically significant difference in clearance was found between Westerners and Japanese.