Healthy Korean Subjects Research Articles

PBPK model-based gender-specific risk assessment of N-nitrosodimethylamine (NDMA) using human biomonitoring data.

Despite several screening levels for NDMA reported in water, soil, air, and drugs, the human risk assessment using biomonitoring concentrations has not been performed. In this study, gender-specific exposure guidance values were determined in humans, then biomonitoring measurements in healthy Korean subjects (32 men and 40 women) were compared to the exposure guidance values to evaluate the current exposure level to NDMA. For the human risk assessment of NDMA, the gender-specific physiologically based pharmacokinetic (PBPK) model was developed in humans using proper physiological parameters, partition coefficients, and biochemical parameters. Using the PBPK model, a Monte Carlo simulation was performed to describe the magnitudes of inter-individual variability and uncertainty on the single model predictions. The PBPK modeling and Monte Carlo simulation allowed the estimation of the relationship between external dose and blood concentration for the risk assessment. The procedure for the human risk assessment was summarized as follows: (1) estimating a steady-state blood concentration (Cavg) corresponding to the daily no observed adverse effect level (NOAEL) administration in rats; (2) applying uncertainty factors (UFs) for deriving the human Cavg; (3) determining the exposure guidance values as screening criteria; (4) interpreting the human biomonitoring measurements by forward and reverse dosimetry approaches. Using the biomonitoring concentrations, current daily exposures to NDMA were estimated to be 3.95μg/day/kg for men and 10.60μg/day/kg for women, respectively. The result of the study could be used as a basis for implementing further risk management and regulatory decision-making for NDMA.

Pharmacodynamics Between a Dual Delayed-Release Formulation of Low-Dose Esomeprazole and Famotidine in Healthy Korean Subjects

PurposeGastritis, one of the most common clinically diagnosed conditions, is defined as the infiltration of inflammatory cells into the gastric mucosa. Drugs for gastritis include histamine-2 receptor antagonists and proton pump inhibitors (PPIs), which reduce acidity in the stomach, and antacids, which neutralize acid. Esomeprazole is a PPI for gastroesophageal reflux disease and gastric and duodenal ulcers that has been shown to be safe and effective at a 10 mg dose. Dual-release drugs have not yet been approved for the treatment of gastritis domestically or internationally. In this study, a dual delayed-release (DR) esomeprazole (10 mg), was compared to famotidine (20 mg) to determine its effectiveness in the treatment of gastritis. MethodsThis study was a randomized, open-label, multiple-dose, 2-treatment, 2-period, 2-sequence crossover study with a 7-day washout between periods. In each period, the subjects were administered one dose of esomeprazole (10 mg) or famotidine (20 mg) for 7 days at each period. The 24-hour gastric pH was recorded after single and multiple doses. The percentage of time (duration%) that the pH was maintained above 4 in the 24 hours after 7 days of repeated dosing was evaluated. FindingsThe mean percentages of time that the gastric pH was above 4 after multiple doses over 7 days of a dual DR esomeprazole (10 mg) and famotidine (20 mg) was 47.31% ± 14.85% and 23.88% ± 10.73%. ImplicationsMultiple doses of a dual DR esomeprazole (10 mg) showed effective gastric acid secretion suppression compared to famotidine with comparable safety and tolerability. These results provide evidence supporting the clinical use of a dual DR esomeprazole (10 mg) to treat gastritis.ClinicalTrials.gov identifier: NCT04967014.

A Population Pharmacokinetic Study to Compare a Novel Empagliflozin L-Proline Formulation with Its Conventional Formulation in Healthy Subjects.

Empagliflozin is a sodium-glucose cotransporter 2 (SGLT2) inhibitor that is commonly used for the treatment of type 2 diabetes mellitus (T2DM). CKD-370 was newly developed as a cocrystal formulation of empagliflozin with co-former L-proline, which has been confirmed to be bioequivalent in South Korea. This study aimed to quantify the differences in the absorption phase and pharmacokinetic (PK) parameters of two empagliflozin formulations in healthy subjects by using population PK analysis. The plasma concentration data of empagliflozin were obtained from two randomized, open-label, crossover, phase 1 clinical studies in healthy Korean subjects after a single-dose administration. A population PK model was constructed by using a nonlinear mixed-effects (NLME) approach (Monolix Suite 2021R1). Interindividual variability (IIV) and interoccasion variability (IOV) were investigated. The final model was evaluated by goodness-of-fit (GOF) diagnostic plots, visual predictive checks (VPCs), prediction errors, and bootstrapping. The PK of empagliflozin was adequately described with a two-compartment combined transit compartment model with first-order absorption and elimination. Log-transformed body weight significantly influenced systemic clearance (CL) and the volume of distribution in the peripheral compartment (V2) of empagliflozin. GOF plots, VPCs, prediction errors, and the bootstrapping of the final model suggested that the proposed model was adequate and robust, with good precision at different dose strengths. The cocrystal form did not affect the absorption phase of the drug, and the PK parameters were not affected by the different treatments.

Gordonibacter faecis sp. nov., producing urolithin C from ellagic acid, isolated from feces of healthy Korean subjects.

A Gram-stain-positive, anaerobic, motile, and short rod-shaped bacterium, designated KGMB12511T, was isolated from the feces of healthy Koreansubjects. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain KGMB12511T was closely related to Gordonibacter pamelaeae 7-10-1-bT (95.2%). The draft genome of KGMB12511T comprised 33 contigs and 2,744 protein-coding genes. The DNA G + C content was 59.9% based on whole-genome sequences. The major cellular fatty acids (>10%) of strain KGMB12511T were C18:1 cis9, C18:1 cis9 DMA (dimethylacetal), and C16:0 DMA. The predominant polar lipids included a diphosphatydilglycerol, four glycolipids, and an unidentified phospholipid. The major respiratory quinones were menaquinone 6 (MK-6) and monomethylmenaquinone 6 (MMK-6). Furthermore, HPLC analysis demonstrated the ability of strain KGMB12511T to convert ellagic acid into urolithin. Based on a comprehensive analysis of phenotypic, chemotaxonomic, and phylogenetic data, strain KGMB12511T represents a novel species in the genus Gordonibacter. The type strain is KGMB12511T (= KCTC 25343T = NBRC 116190T).

Novel bioequivalent oral disintegrating tablet of aripiprazole prepared by direct compression technique with shortened disintegration time

Herein, we aimed to formulate a novel oral disintegrating tablet (ODT) of aripiprazole (ARP) capable of rapid disintegration using a direct compression technique. Different ODTs were fabricated with directly compressible excipients, and their disintegration time, wettability (water absorption ratio and wetting time), and mechanical properties (hardness and friability) were evaluated. The optimized ODT comprised F-Melt® type C, Prosolv® SMCC HD90, and Na croscarmellose (10 mg of ARP in a 130 mg tablet). The ODT with 3.1–5.2 kp hardness exhibited rapid disintegration (14.1–17.2 sec), along with appropriate mechanical strength (friability < 0.24%). In a bioequivalent study in Korean healthy subjects (randomized, single-dose, two-period crossover design, n = 37), the novel ODT offered the equivalent pharmacokinetic profile to that of a conventional immediate release tablet (Otsuka, Abilify®, Japan), despite different disintegration and dissolution profiles. The 90% confidence intervals of the geometric mean test to reference ratios considering the area-under-the-curve and maximum plasma drug concentrations were 1.0306–11051 and 0.9448–1.1063, respectively, satisfying FDA regulatory criteria for bioequivalence. The novel ART ODT was physicochemically stable under the accelerated storage condition (40 °C, RH75%) for 24 weeks. Therefore, the novel ARP-loaded ODT is expected to be an alternative to oral ARP therapy, providing improved patient adherence.

Effects of food and ethnicity on the pharmacokinetics of venadaparib, a next-generation PARP inhibitor, in healthy Korean, Caucasian, and Chinese male subjects

AimVenadaparib is a next-generation poly(ADP-ribose) polymerase inhibitor under development for treating gastric cancer. This study aimed to evaluate the effects of food and ethnicity on the pharmacokinetics (PKs) and safety of venadaparib after a single oral administration in healthy Korean, Caucasian, and Chinese male subjects.MethodsIn this randomized, open-label, single-dose, two-sequence, two-period, and crossover study, Korean and Caucasian subjects received venadaparib 80 mg in each period (fasted or fed state) with a seven-day washout. In an open-label, single-dose study, Chinese subjects received venadaparib 80 mg only in the fasted state. Serial blood samples were collected up to 72 h post-dosing.ResultsTwelve subjects from each ethnic group completed the study. The geometric mean ratios (90% confidence intervals) of the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from time zero to the last measurable time point (AUClast) of venadaparib for the fed to fasted state were 0.82 (0.7457–0.9094) and 1.02 (0.9088–1.1339) in Koreans, and 0.77 (0.6871–0.8609) and 0.96 (0.9017–1.0186) in Caucasians, respectively. No statistically significant differences were observed in Cmax (P-value = 0.45) or AUClast (P-value = 0.30) among the three ethnic groups. A single venadaparib dose was well-tolerated.ConclusionThe overall systemic exposure of venadaparib was not affected by the high-fat meal, despite delayed absorption with a decreased Cmax in the fed state. The PK profiles were comparable among the Korean, Caucasian, and Chinese subjects. A single venadaparib 80 mg dose was safe and well-tolerated in both fasted and fed states.

One-year antibody durability induced by EuCorVac-19, a liposome-displayed COVID-19 receptor binding domain subunit vaccine, in healthy Korean subjects

ObjectiveEuCorVac-19 (ECV-19), an adjuvanted liposome-displayed receptor binding domain (RBD) COVID-19 vaccine, previously reported interim Phase 2 trial results showing induction of neutralizing antibodies 3 weeks after prime-boost immunization. The objective of this study was to determine the longer-term antibody response of the vaccine. MethodsTo assess immunogenicity 6 and 12 months after vaccination, participants in the Phase 2 trial (NCT04783311) were excluded if they: 1) withdrew, 2) reported COVID-19 infection or additional vaccination, or 3) exhibited increasing Spike (S) antibodies (representing possible non-reported infection). Following exclusions, of the 197 initial subjects, anti-S IgG antibodies and neutralizing antibodies were further assessed in 124 subjects at the 6-month timepoint, and 36 subjects at the 12-month timepoint. ResultsMedian anti-S antibody half-life was 52 days (interquartile range [IQR]:42-70), in the “early” period from 3 weeks to 6 months, and 130 days (IQR:97-169) in the “late” period from 6 to 12 months. There was a negative correlation between initial antibody titer and half-life. Anti-S and neutralizing antibody responses were correlated. Neutralizing antibody responses showed longer half-lives; the early period had a median half-life of 120 days (IQR:81-207), and the late period had a median half-life of 214 days (IQR:140-550). ConclusionThese data establish antibody durability of ECV-19, using a framework to analyze COVID-19 vaccine-induced antibodies during periods of high infection.

Evaluation of the comparative pharmacokinetic properties of a new orally disintegrating tablet of tegoprazan in healthy Korean subjects.

Tegoprazan is a differentiated gastric acid-pump blocker and belongs to a class of potassium-competitive acid secretion blockers. An orally disintegrating tablet (ODT) of tegoprazan was developed to improve patient compliance. The purpose of this study was to compare pharmacokinetics (PK) and safety profiles between the conventional tablet (as the reference drug) and the ODT (as the test drug) of 50 mg tegoprazan in healthy Korean subjects. An open-label, randomized, single-dose, 6-sequence, 3-period crossover study was conducted in 48 healthy subjects. All subjects received a single oral dose of tegoprazan 50mg tablet with water, tegoprazan 50mg ODT with water, and tegoprazan 50mg ODT without water. Serial blood samples were collected up to 48hours after dosing. Plasma concentrations of tegoprazan and its metabolite M1 were measured by LC-MS/MS, and PK parameters were calculated with a non-compartmental method. Safety was evaluated by means of assessed adverse events, physical examinations, laboratory test results as well as measurements of vital signs and ECG throughout the study. A total of 47 subjects completed the study. The 90% confidence intervals of the geometric mean ratios for AUCt, Cmax, and AUCinf of tegoprazan were 0.8873-0.9729, 0.8865-1.0569, and 0.8835-0.9695 for the test drug with water to the reference drug and 0.9169-1.0127, 0.9569-1.1276, and 0.9166-1.0131 for the test drug without water to the reference drug, respectively. There were no serious adverse events, and all adverse events were mild. The PK profiles of tegoprazan were equivalent between the conventional tablet and ODT with or without water. There was no significant difference in the safety profiles. Therefore, the novel ODT of tegoprazan that can be taken without water may improve compliance among patients with acid-related diseases.

Effects of CYP2D6 and CYP2C19 genetic polymorphisms and cigarette smoking on the pharmacokinetics of tolperisone.

Tolperisone, a muscle relaxant used for post-stroke spasticity, is metabolized to its main metabolite by CYP2D6 and to a lesser extent by CYP2C19 and CYP1A2. We investigated the effects of CYP2D6 and CYP2C19 genetic polymorphisms and cigarette smoking on tolperisone pharmacokinetics. A 150mg oral dose of tolperisone was given to 184 healthy Korean subjects and plasma concentrations of tolperisone were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A 3.14-fold significant increase in AUC0-∞ was observed in the CYP2D6*10/*10 group compared with the CYP2D6*wt/*wt group, whereas a 3.59-fold increasein AUC0-∞ was observed in CYP2C19PMs compared to CYP2C19EMs. Smokers had a 38.5% decrease in AUC0-∞ when compared to non-smokers. When these effects were combined, CYP2D6*10/*10-CYP2C19PM-Non-smokers had a 25.9-fold increase in AUC0-∞ compared to CYP2D6*wt/*wt-CYP2C19EM-Smokers. Genetic polymorphisms of CYP2D6 and CYP2C19 and cigarette smoking independently and significantly affected tolperisone pharmacokinetics and these effects combined resulted in a much greater impact on tolperisone pharmacokinetics.

Pharmacokinetic and pharmacodynamic exploration of various combinations of tegoprazan immediate and delayed-release formulations.

The new modified-release formulation of tegoprazan, a novel potassium-competitive acid blocker, is expected to improve the management of acid-related disease, including nocturnal acid breakthrough, by prolonging the duration of acid suppression. This study aimed to explore the pharmacokinetics (PK) and pharmacodynamics (PD) of various combinations of tegoprazan with immediate-release (IR) and delayed-release (DR) formulations. A three-cohort, open-label, randomized, single-dose, three-treatment, six-sequence, three-period crossover study was conducted. Various combinations of tegoprazan IR and DR formulations (50, 75 or 100 mg) were administered orally once per period. The 24-h intragastric pH was monitored before and after each administration. PK blood samples were collected for up to 48 h. PK and PD were compared among treatments. Eighteen healthy Korean subjects completed the study. All treatment groups showed intragastric pH above 4 approximately 1h following tegoprazan administration. Among the various combinations, the IR and DR combination at a 1:1 ratio induced greater gastric acid suppression (%Time pH ≥ 4) than IR alone in each dose group, both for 24 h (50 mg; 59% vs. 52%, P = .2188, 95% confidence interval [CI] -6.92-22.27, 100 mg; 85% vs. 70%, P < .05, 95% CI 8.92-22.19) and at night (50 mg; 27% vs. 16%, P = .1563, 95% CI -11.79-37.71, 100 mg; 77% vs. 49%, P < .05, 95% CI 16.14-42.98), with similar systemic exposure. The combinatorial tegoprazan in the IR and DR 1:1 ratio formulation was found to induce stronger gastric acid suppression throughout the day and at night, compared to the conventional IR formulation.

Model Informed Development of SIM0295 in Patients with Gout and Hyperuricemia and Healthy Volunteers Using a Population Pharmacokinetics/ Pharmacodynamics Approach

ABSTRACT Background SIM0295, a novel inhibitor of human uric acid transporter 1 (hURAT1), is used to treat patients with gout and hyperuricemia. This study aimed to develop population pharmacokinetics and pharmacodynamics (popPK/PD) models of SIM0295 and explore potential covariates to inform clinical drug development. Research design and methods Data were obtained from four phase I studies conducted in healthy Korean and Chinese subjects and two phase II studies conducted in Korean patients with gout and hyperuricemia. The popPK/PD model of SIM0295 was developed using nonlinear mixed effects modeling. Results SIM0295 pharmacokinetics was described using a two-compartment model with the absorption of four transit compartments and first-order elimination. PK parameters were normalized to weight via allometric scaling. Food was identified as a factor significantly affecting the absorption rate, with no clinical relevance. The sigmoid Emax model with a semi-mechanism of inhibition of serum uric acid (sUA) reabsorption was used to describe the exposure-response relationship. Additionally, Monte Carlo simulations demonstrated that approimately 9 mg/day of SIM0295 for 7 days could achieve the maximum decrease in sUA. Conclusion The established popPK/PD model characterized the dose-exposure-response relationship for SIM0295 in healthy subjects and patients with gout and hyperuricemia and could be used to inform the drug development.

Comparative pharmacokinetics of two formulations of 2.5-mg rivaroxaban in healthy Korean subjects.

Rivaroxaban is a direct factor Xa inhibitor used for the prevention and treatment of thromboembolic disorders. The objective of this study was to compare the pharmacokinetic profiles of two rivaroxaban formulations after a single dose of rivaroxaban (2.5-mg tablet) in healthy Korean subjects. This study was a randomized, open-label, single-dose, two-period, crossover study that included 34 healthy adult subjects under fasting conditions. The test drug (Yuhan rivaroxaban tablet) or reference drug (Xarelto tablet) was administered in each period. Serial blood samples were collected up to 36 hours post-dose. Plasma concentrations were measured by LC-MS/MS. Pharmacokinetic parameters, including maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from time zero to the last measurable concentration (AUCt), were determined by non-compartmental analysis. The 90% confidence intervals (CIs) for the ratio of the geometric means of Cmax and AUCt for the test drug/reference drug were calculated to evaluate pharmacokinetic equivalence. A total of 28 subjects were included in the pharmacokinetic analysis. The geometric mean ratios (90% CI) of the test drug/reference drug for rivaroxaban were 1.0140 (0.9794-1.0499) for AUCt and 0.9350 (0.8797-0.9939) for Cmax. All adverse events (AEs) were mild, and there was no significant difference in the incidence of AEs between the formulations. The pharmacokinetic parameters of rivaroxaban were compared between the test and reference drug, and both formulations were bioequivalent. The newly developed rivaroxaban tablet is safe and well tolerated as the reference drug (ClinicalTrials.gov identifiers: NCT05418803).

Understanding the bacterial compositional network associations between oral and gut microbiome within healthy Koreans

ABSTRACT Oral microbial ecosystem could influence intestinal diseases, but there have been insufficient studies demonstrating the association of microbial composition between the oral cavity and the intestinal system. Thus, we aimed to investigate the compositional network within the oral microbiome related to gut enterotype from saliva and stool samples collected from 112 healthy Korean subjects. Here, we performed bacterial 16S amplicon sequencing from clinical samples. Then, we determined oral microbiome type related to individual’s gut enterotype for healthy Korean. The co-occurrence analysis was performed to interactivity prediction of microbiome within saliva samples. As a result, it could be classified into two Korean oral microbiome types (KO) and four oral–gut-associated microbiome types (KOGA) according to distribution and significant differences of oral microflora. The co-occurrence analysis showed various bacterial compositional networks linked around Streptococcus and Haemophilus within healthy subjects. The present study was first approach in healthy Koreans to identify the oral microbiome types related to the gut microbiome and investigate their characteristics. Hence, we suggest that our results could be potential healthy control data for identifying differences in microbial composition between healthy people and oral disease patients and studying microbial association with the gut microbial environment (oral–gut microbiome axis).

Early response of the gut microbiome and serum metabolites to Cheonggukjang intake in healthy Korean subjects

Early response of the gut microbiome and serum metabolites to Cheonggukjang intake in healthy Korean subjects

Prevalence, Distribution, and Concomitance of Whole-Spine Ossification of the Posterior Longitudinal Ligament and Ossification of the Ligament Flavum in South Koreans: A Whole-Spine-CT-Based Cross-Sectional Study.

No studies assessing the prevalence of ossification of the spinal ligament were conducted using whole-spine positron emission tomography and computed tomography (PET-CT) in healthy Koreans. We aimed to determine the prevalence of ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligament flavum (OLF) in healthy Koreans using whole-body PET-CT. We reviewed whole-body PET-CT images captured during general health checkups at the General Health Promotion Center of our institution from January 2015 to 2020. OPLL and OLF were identified by the presence of heterotopic ossification in the posterior longitudinal ligament and ligament flavum on axial and sagittal PET-CT images. A total of 1,934 adults (1,645 men, 289 women) were included. The mean age was 48.05 years (range, 28-86 years). Among the 1,934 patients, 173 had OPLL (8.9%). The most commonly involved cervical vertebra levels arranged according to frequency were C4, C5, C3, and C6. OLF was observed in 125 patients (6.5%). The most commonly involved thoracic levels were T10, T11, and T5. The prevalence of OPLL and OLF was the highest in patients aged 60-69 years. Among the C-OPLL patients, 15.1% had T-OPLL, 5.0% had L-OPLL, and 25.8% had T-OLF. Our study revealed the prevalence of OPLL and OLF in healthy Korean subjects. It was consistent with that in other Asian countries. The presence of OPLL and OLF at most locations correlated with the presence or absence of spinal ossification at other locations.

Accuracy of Y-scope, a newly developed portable abdominal impedance analyzer, for the assessment of abdominal visceral fat area.

AimThis study was conducted to evaluate the accuracy of a newly developed multifrequency segmental (MFS) bioelectrical impedance analysis (BIA) method using an additional portable abdominal (PA) impedance analyzer, in the assessment of abdominal visceral fat area (VFA).Materials and methodsOne hundred healthy Korean subjects aged 19 years or over (43 men and 57 women) were recruited, and VFA was estimated by a conventional MFS-BIA machine and a new MFS-BIA machine with a PA-BIA device, indicating MFS-VFA and MFS&PA-VFA, respectively. The accuracy of the VFA values was compared with those evaluated with CT at the level of the umbilicus (CT-VFA).ResultsThe mean age was 41 years and mean body mass index (BMI) was 24.4 kg/m2. The mean ± SD VFAs measured by CT, conventional MFS-BIA, and new MFS&PA-BIA together were 93.4 ± 60.9, 92.7 ± 53.4, and 93.6 ± 55.4 cm2, respectively. Correlation coefficients comparing CT-VFA with MFS-VFA and MFS&PA-VFA were 0.612 and 0.932, respectively (P < 0.001 for both). The mean difference between CT-VFA and MFS&PA-VFA was less affected by age, sex, and BMI compared with that between CT-VFA and MFS-VFA. Intraclass correlation coefficient (95% CI) between CT-VFA and MFS&PA-VFA was also greater than that between CT-VFA and MFS-VFA, 0.96 (0.95–0.98) vs. 0.76 (0.64–0.84), respectively.ConclusionIn this study, application of a newly developed MFS-BIA machine combined with a PA-BIA device significantly improved the correlation with CT-measured VFA without proportional error. This novel approach using advanced technology may be able to provide more reliable estimates of abdominal VFA.

The pharmacokinetic, safety, and tolerability profiles of eslicarbazepine acetate are comparable between Korean and White subjects.

Eslicarbazepine acetate (ESL) is a prodrug antiseizure medication for the treatment of focal seizures. ESL shows a well‐established pharmacokinetic (PK)‐pharmacodynamic relationship and has similar extrinsic epilepsy‐related factors across ethnicities. This study evaluated and compared ESL safety, tolerability, and PK characteristics between Korean and White subjects. A randomized, double‐blind, placebo‐controlled, single‐ and multiple‐dose escalation study was conducted in healthy Korean and White adults. Participants randomly received a single dose and multiple oral doses of ESL (400–1600 mg) or placebo once daily for 11 days at a ratio of 8:2. Serial blood samples were collected to determine the plasma concentration of ESL and its metabolites (eslicarbazepine, [R‐licarbazepine and oxcarbazepine). Safety and tolerability were assessed throughout the study. A total of 29 Korean and 20 White subjects completed the study. The PK profiles of the metabolites of ESL were similar between Korean and White subjects. The geometric mean ratio (90% confidence interval) of Korean to White subjects for the area under the concentration–time curve within a dosing interval of eslicarbazepine was 1.06 (0.97–1.17) and 0.96 (0.87–1.06) after multiple oral doses of 400 and 1600 mg ESL, respectively. Other PK parameters were also similar between the two ethnic groups. ESL was well‐tolerated in healthy Korean and White subjects, and its PK characteristics were similar between the two ethnic groups. The results of this study support to use the same dosage regimen of ESL in both White and Korean patients with seizures.

Pharmacokinetics and Genetic Factors of Atorvastatin in Healthy Korean Subjects.

Background: Statins are the most popular agents for the primary and secondary prevention of cardiovascular disease; however, the pharmacokinetic parameters and associated genetic factors in the Korean population have not been fully elucidated. This study explored the pharmacokinetic properties of atorvastatin and the association between genetic variations and atorvastatin pharmacokinetics in healthy Korean subjects. Methods: Atorvastatin (80 mg) was administered to 35 healthy Korean volunteers. Plasma levels of atorvastatin and its metabolites were measured sequentially using liquid chromatography-tandem mass spectrometry from 0 to 24 h after atorvastatin administration. Customized next-generation sequencing analysis was performed covering all coding exons of 15 genes, as well as 46 single-nucleotide variants in 29 genes related to statin pharmacokinetics. Results: The mean area under the concentration-time (AUC) and Cmax (maximum peak concentration) were 269.0 ng/ml∙h and 84.3 ng/ml, respectively, which were approximately two times higher than those reported in Caucasians. Genetic analysis revealed that eight genetic variants in ABCB1, ABCG2, APOA5, CETP, and CYP7A1 contributed to the AUC of atorvastatin. The atorvastatin AUC0–24 h prediction model was developed based on age and eight genetic variants using multivariate linear regression (adjusted R 2 = 0.878, p < 0.0001). Conclusion: This study shows that the pharmacokinetic properties of atorvastatin in Koreans are different from those in Caucasians and that atorvastatin AUC0–24 h could be predicted based on age and eight genetic variants of ABCB1, ABCG2, APOA5, CETP, and CYP7A1.

Population pharmacokinetic modeling and simulation of choline in healthy Korean subjects after oral administration of choline alfoscerate

Population pharmacokinetic modeling and simulation of choline in healthy Korean subjects after oral administration of choline alfoscerate

Evaluation of sex differences in the pharmacokinetics of oral sumatriptan in healthy Korean subjects using population pharmacokinetic modeling.

Sumatriptan was introduced in 1983, as the first of the triptans, selective 5‐hydroxytryptamine (5‐HT1B/1D) receptor agonists, to treat moderate to severe migraine. Migraine predominates in females. Although there have been reports of sex differences in migraine‐associated features and pharmacokinetics (PKs) of some triptans, sex differences in the PKs of oral sumatriptan have never been evaluated in Korean. We conducted this study of oral sumatriptan to assess the sex differences in Korean population. Thirty‐eight healthy Korean subjects who participated in two separate clinical studies receiving a single oral dose of 50 mg sumatriptan with the same protocols were included in this analysis. A total of 532 sumatriptan concentration observations were used for a population PK modeling. Validation of final population PK model of sumatriptan was performed using bootstrap and visual predictive check. The PK profile of oral sumatriptan was adequately described by a one‐compartmental model with combined transit compartment model and a first‐order absorption. The covariate analysis showed that the clearance of oral sumatriptan was significantly higher in males than in females (male: 444 L/h, female: 281 L/h). Our results showed that there were sex differences in the clearance of oral sumatriptan. These results encourage further studies to establish the sumatriptan pharmacokinetic–pharmacodynamic model considering sex‐related PK differences, which may help to determine optimal dosing regimens for effective treatment of migraine in males and females. Clinical trial registration: CRIS Registration No. KCT0001784.