Estrogen-related receptor γ negatively regulates osteoclastogenesis and protects against inflammatory bone loss.

Estrogen-related receptor γ (ERRγ) is an orphan nuclear receptor that plays an important role in various metabolic processes under physiological and pathophysiological conditions. Here, we report that ERRγ functions as a negative regulator in receptor activator of nuclear factor κΒ ligand (RANKL)-induced osteoclast differentiation. We observed that ERRγ was strongly expressed in osteoclast precursors, bone marrow-derived macrophages (BMMs) while its expression was significantly reduced by RANKL during osteoclastogenesis. Overexpression of ERRγ in BMMs suppressed the formation of multinucleated osteoclasts and attenuated the induction of c-Fos and nuclear factor of activated T cells c1, which are critical modulators in osteoclastogenesis. Similarly, the treatment of ERRγ agonists, N-(4-(diethylaminobenzylidenyl)-N'-(4-hydroxybenzoyl)-hydrazine (DY131) or GSK4716, also inhibited osteoclast generation and the expression of these key modulators. On the other hand, shRNA-mediated knockdown of ERRγ accelerated the formation of bone-resorbing cells and the expression of osteoclastogenic markers. Forced expression of ERRγ blocked RANKL-stimulated phosphorylation of the nuclear factor κB (NF-κB) inhibitor IκBα and suppressed NF-κB transcriptional activity induced by RANKL or the NF-κB subunit p65. Furthermore, by employing a pharmacological approach, we showed that the ERRγ agonist DY131 protected against inflammatory bone loss induced by lipopolysaccharide in vivo. Together, our findings reveal that ERRγ is a pivotal regulator in RANKL-mediated osteoclastogenesis and suggest that ERRγ may have potential as a therapeutic target for pathological bone loss.

Detection of 13 Ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, Rg3, Rh2, F1, Compound K, 20(S)-Protopanaxadiol, and 20(S)-Protopanaxatriol) in Human Plasma and Application of the Analytical Method to Human Pharmacokinetic Studies Following Two Week-Repeated Administration of Red Ginseng Extract.

We aimed to develop a sensitive method for detecting 13 ginsenosides using liquid chromatography-tandem mass spectrometry and to apply this method to pharmacokinetic studies in human following repeated oral administration of red ginseng extract. The chromatograms of Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, Rg3, Rh2, F1, compound K (CK), protopanaxadiol (PPD), and protopanaxatriol (PPT) in human plasma were well separated. The calibration curve range for 13 ginsenosides was 0.5-200 ng/mL and the lower limit of quantitation was 0.5 ng/mL for all ginsenosides. The inter- and intra-day accuracy, precision, and stability were less than 15%. Among the 13 ginsenosides tested, nine ginsenosides (Rb1, Rb2, Rc, Rd, Rg3, CK, Rh2, PPD, and PPT) were detected in the human plasma samples. The plasma concentrations of Rb1, Rb2, Rc, Rd, and Rg3 were correlated with the content in red ginseng extract; however, CK, Rh2, PPD, and PPT were detected although they are not present in red ginseng extract, suggesting the formation of these ginsenosides through the human metabolism. In conclusion, our analytical method could be effectively used to evaluate pharmacokinetic properties of ginsenosides, which would be useful for establishing the pharmacokinetic-pharmacodymic relationship of ginsenosides as well as ginsenoside metabolism in humans.

G protein-coupled receptor 84 controls osteoclastogenesis through inhibition of NF-κB and MAPK signaling pathways.

GPR84, a member of the G protein-coupled receptor family, is found predominantly in immune cells, such as macrophages, and functions as a pivotal modulator of inflammatory responses. In this study, we investigated the role of GPR84 in receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. Our microarray data showed that GPR84 was significantly downregulated in osteoclasts compared to in their precursors, macrophages. The overexpression of GPR84 in bone marrow-derived macrophages suppressed the formation of multinucleated osteoclasts without affecting precursor proliferation. In addition, GPR84 overexpression attenuated the induction of c-Fos and nuclear factor of activated T cells, cytoplasmic 1 (NFATc1), which are transcription factors that are critical for osteoclastogenesis. Furthermore, knockdown of GPR84 using a small hairpin RNA promoted RANKL-mediated osteoclast differentiation and gene expression of osteoclastogenic markers. Mechanistically, GPR84 overexpression blocked RANKL-stimulated phosphorylation of IκBα and three MAPKs, JNK, ERK, and p38. GPR84 also suppressed NF-κB transcriptional activity mediated by RANKL. Conversely, GPR84 knockdown enhanced RANKL-induced activation of IκBα and the three MAPKs. Collectively, our results revealed that GPR84 functions as a negative regulator of osteoclastogenesis, suggesting that it may be a potential therapeutic target for osteoclast-mediated bone-destructive diseases.

Neuromedin B and its receptor silencing suppresses osteoclast generation by modulating precursor proliferation via M-CSF/c-Fms/D-type cyclins.

Neuromedin B (NMB), a mammalian bombesin-like peptide, regulates diverse physiological processes, such as energy metabolism, memory and fear behavior, and cellular growth, through its cognate receptor, NMBR. In this study, we report that NMB expression was upregulated during osteoclast development and that silencing NMB or NMBR attenuated osteoclast generation mediated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL). We found that knockdown of NMB or NMBR using a small hairpin RNA suppressed M-CSF-induced proliferation of osteoclast precursor cells without altering osteoclast differentiation. Interestingly, NMB or NMBR knockdown reduced the expression of the M-CSF receptor, c-Fms, which is an important modulator of osteoclast development. Consequently, NMB or NMBR silencing inhibited M-CSF/c-Fms-mediated downstream signaling pathways like activation of ERK and Akt and induction of D-type cyclins, cyclin D1 and D2. Moreover, knockdown of NMB or NMBR accelerated apoptosis in osteoclast lineage cells by inducing caspase-3, caspase-9, and Bim expression. In summary, our study demonstrates that the NMB/NMBR axis plays a pivotal role in osteoclast generation by modulating the proliferation and survival of osteoclast lineage cells.

Pharmacokinetics and bioequivalence of a rosuvastatin/ezetimibe fixed-dose combination tablet versus single agents in healthy male subjects
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OBJECTIVE: The pharmacokinetic profiles and bioequivalence of a new rosuvastatin/ezetimibe fixed-dose combination (FDC; NVP-1205) vs. rosuvastatin and ezetimibe concomitantly administered as single agents were evaluated. MATERIALS AND METHODS: In this open-label, single-dose, crossover study (NCT02029625), eligible subjects were randomly assigned in a 1 : 1 ratio to receive a single dose of rosuvastatin (10 mg) with ezetimibe (10 mg) as either a FDC or as single agents concomitantly administered under fasted conditions, followed by a 2-week washout period and administration of the alternate formulation. Serial blood samples were collected predose and up to 96 hours postdose in each period for determination of plasma rosuvastatin and ezetimibe concentrations by liquid-chromatography tandem mass spectroscopy and calculation of pharmacokinetic parameters. RESULTS: The mean Cmax and AUC0-t values of rosuvastatin were 12.5 ng/mL and 115.6 ng×h/mL for the FDC, and 12.2 ng/mL and 115.1 ng×h/mL for the single agents concomitantly administered, respectively. The mean Cmax and AUC0-t values of ezetimibe were 4.7 ng/mL and 67.3 ng×h/mL for the FDC, and 4.5 ng/mL and 68.2 ng×h/mL for the single agents concomitantly administered, respectively. The geometric mean ratio (GMR) and 90% confidence interval (CI) for the rosuvastatin Cmax and AUC0-t were 106.20 (96.62 - 116.74) and 102.88 (96.32 - 109.90), respectively. The GMR and 90% CI for the ezetimibe Cmax and AUC0-t were 108.96 (98.56 - 120.51) and 98.13 (92.01 - 104.66), respectively. All treatments were well tolerated during this study, with no serious adverse events reported. CONCLUSION: The rosuvastatin/ezetimibe (10/10 mg) FDC was bioequivalent to single agents concomitantly administered. A single dose of rosuvastatin/ezetimibe as the FDC or as single agents was well tolerated.
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G Protein-Coupled Receptor 120 Signaling Negatively Regulates Osteoclast Differentiation, Survival, and Function.

G protein-coupled receptor 120 (GPR120) plays an important role in the regulation of inflammation and lipid metabolism. In this study, we investigated the role of GPR120 in osteoclast development and found that GPR120 regulates osteoclast differentiation, survival and function. We observed that GPR120 was highly expressed in osteoclasts compared to their precursors, bone marrow-derived macrophages (BMMs). Activation of GPR120 by its ligand GW9508 suppressed receptor activator of NF- κB ligand (RANKL)-induced osteoclast differentiation and the expression of nuclear factor of activated T cells c1 (NFATc1), a key modulator of osteoclastogenesis. GPR120 activation further inhibited the RANKL-stimulated phosphorylation of IκBα and JNK. In addition to osteoclast differentiation, GPR120 activation increased the apoptosis of mature osteoclasts by inducing caspase-3 and Bim expression. Activation of GPR120 also interfered with cell spreading and actin cytoskeletal organization mediated by M-CSF but not by RANKL. Coincident with the impaired cytoskeletal organization, GPR120 activation blocked osteoclast bone resorbing activity. Furthermore, knockdown of GPR120 using small hairpin RNA abrogated all these inhibitory effects on osteoclast differentiation, survival, and function. Together, our findings identify GPR120 as a negative modulator of osteoclast development that may be an attractive therapeutic target for bone-destructive diseases. J. Cell. Physiol. 231: 844-851, 2016. © 2015 Wiley Periodicals, Inc.

Pharmacokinetic drug interaction study using fimasartan and rosuvastatin in healthy volunteers.

OBJECTIVE: This study evaluated the possible pharmacokinetic interactions between rosuvastatin and fimasartan, an angiotensin II type 1 (AT1) receptor blocker (ARB), approved in Korea for the treatment of mild to moderate hypertension. METHODS: In this open-label, multiple-dose, two-period, single-sequence study, the enrolled subjects were randomized into two separate parts (A and B). In part A, subjects received 120 mg of fimasartan alone for 7 days during period I, and 120 mg fimasartan with 20 mg rosuvastatin for 7 days during period II. In Part B, subjects received rosuvastatin alone, followed by concomitant administration of fimasartan, with the same doses used as in Part A. There was a 7-day washout between periods I and II. Serial blood samples were collected for up to 48 hours for fimasartan and for up to 72 hours for rosuvastatin after the last dose of each period to determine the steady-state pharmacokinetics of both drugs. RESULTS: The mean Cmax,ss and AUCτ,ss values of fimasartan were 258.03 ± 176.75 ng/mL and 746.52 ± 273.49 ng×h/mL for fimasartan alone, and 289.40 ± 231.44 ng/mL and 848.43 ± 267.45 ng×h/mL for fimasartan and rosuvastatin coadministration, respectively (p-values for Cmax,ss and AUCτ,ss, 0. 513 and 0.006, respectively). The mean Cmax,ss and AUCτ,ss values of rosuvastatin were 9.94 ± 4.48 ng/mL and 85.29 ± 36.25 ng×h/mL for rosuvastatin alone and 11.94 ± 8.47 ng/mL and 77.33 ± 38.71 ng×h/mL for fimasartan and rosuvastatin coadministration, respectively (p-values for Cmax,ss and AUCτ,ss, 0.066 and 0.009, respectively). The geometric mean ratio (GMR) and 90% confidence intervals (CI) for the Cmax,ss and AUCτ,ss of fimasartan (with/without rosuvastatin) were 1.109 (0.813 - 1.511) and 1.159 (1.061 - 1.265), respectively. The GMR and 90% CI for the Cmax,ss and AUCτ,ss of rosuvastatin (with/without fimasartan) were 1.090 (0.979 - 1.213) and 0.870 (0.804 - 0.940), respectively. CONCLUSIONS: These results suggest that fimasartan and rosuvastatin have no relevant pharmacokinetic drug-drug interactions. All treatments were well tolerated during this study, with no serious adverse effects.
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Comparative Pharmacokinetic Profiles of a Novel Low-Dose Micronized Formulation of Raloxifene 45 mg (AD-101) and the Conventional Raloxifene 60 mg in Healthy Subjects.

Raloxifene hydrochloride shows poor bioavailability (only 2%) when orally administered because of its poor aqueous solubility and its extensive first-pass metabolism. A new micronized formulation of raloxifene was developed to improve bioavailability via enhanced gastrointestinal absorption. The primary objective of this study was to evaluate the pharmacokinetic characteristics of a new micronized raloxifene formulation (AD-101) in comparison with the conventional raloxifene formulation. This study was designed as an open-label, randomized, 2-treatment-period, crossover study with a 2-week washout period. Two treatments consisted of micronized raloxifene 45 mg daily; and conventional raloxifene 60 mg daily administered in fasting conditions. Plasma raloxifene concentrations were determined by a validated method using ultra-fast liquid chromatography-tandem mass spectrometry, and pharmacokinetic parameters were calculated using a noncompartmental model. In total, 49 subjects completed the study. The geometric mean ratio (micronized/conventional) of the maximum concentration and the area under the plasma concentration-time curve from time zero to the last concentration values were 1.08 (90% CI, 0.95-1.24) and 0.97 (90% CI, 0.89-1.05), respectively. The adverse event profile did not differ between the 2 formulations. The results demonstrate that micronized formulation of raloxifene 45 mg is equivalent to conventional formulation of raloxifene 60 mg when administered at the single dose in the fasted state. After single oral dosing of AD-101, there were no serious or unexpected adverse events.

Fed and fasted bioequivalence assessment of two formulations of extended-release fixed-dose combination dapagliflozin/metformin (10/1,000 mg) tablets in healthy subjects.

Two open-label, randomized, two-period crossover studies were conducted to investigate the pharmacokinetic (PK) properties, safety, and bioequivalence of the test formulation (KD4004), a new fixed-dose combination (FDC) formulation of dapagliflozin and metformin extended release (XR) tablets, relative to the reference formulation (10 mg dapagliflozin/1,000 mg metformin XR FDC tablet) in healthy subjects under fasting (Part A) and fed (Part B) conditions. After giving the dose, serial blood samples were collected for a period of 48 hours. Primary PK parameters (AUC0-t and Cmax) were used to assess bioequivalence between two dapagliflozin/metformin XR (10/1,000 mg) FDC formulations under fed and fasting conditions. Safety and tolerability were also evaluated. Part A and Part B were completed by 32 and 37 subjects, respectively. Bioequivalence of the two FDC formulations of dapagliflozin and metformin XR tablets was established in both the fasted and the fed conditions as the 90% confidence interval of the ratios of adjusted geometric means for AUC0-t and Cmax were contained within the predefined range of 0.800-1.250 bioequivalence criteria. Single-dose administration of dapagliflozin and metformin XR was safe and well tolerated as the two FDC formulations. In conclusion, both FDC formulations of dapagliflozin and metformin XR tablets were bioequivalent in fed and fasted subjects. All treatments were well tolerated. Trial Registration: Clinical Research Information Service Identifier: KCT0004026.

Pharmacokinetics and Pharmacodynamics of YYD601, a Dual Delayed-Release Formulation of Esomeprazole, Following Single and Multiple Doses in Healthy Adult Volunteers Under Fasting and Fed Conditions.

Background: YYD601 was developed as a novel dual delayed release (DDR) formulation of esomeprazole to prolong the plasma esomeprazole concentration and extend the duration of acid suppression. Purpose: The pharmacokinetic (PK) and pharmacodynamics (PD) characteristics of YYD601 after single and multiple oral administrations were investigated in healthy Korean adults under fasting and fed conditions, and compared with the original esomeprazole capsule. Methods: In the single-center, randomized, open-label, parallel-design, two-period study, thirty two volunteers were enrolled into four dosing groups, including esomeprazole 40-mg (group A), YYD60130-mg (group B), YYD601 40-mg (group C), and YYD601 60-mg (group D) once daily for 5 days. Blood samples were collected for PK analysis, before and up to 24 h after dosing. For PD characteristics of YYD601, the percentages of time with intragastric pH > 4 over a 24-h period and during night-time following multiple oral administrations were evaluated. Results: A total of 27 subjects completed the study. YYD601 showed a dual-peak PK profile under fasting condition, with delayed Tmax, compared with conventional formulation. There were no significant differences in the AUC values adjusted for dose between the three YYD601 dosage groups and the conventional esomeprazole 40 mg. The esomeprazole AUC following single and multiple administration decreased with food intake by approximately 33%. YYD601 showed a linear pharmacokinetic profile in the dose range studied. There was no statistically significant difference in increase in mean percentage of time with intragastric pH > 4 for 24-hour and during night-time between the three different doses of YYD601 and the conventional formulation. The treatments were well-tolerated during the study and no serious adverse events were observed. Conclusion: YYD601 30 mg has a comparable effect on gastric acid inhibition as conventional esomeprazole 40 mg following once daily oral administration. Single and multiple oral dosing of YYD601 up to 60 mg were safe and well-tolerated throughout the study. Clinical Trial Registry: http://clinicaltrials.gov, NCT03558477 (date of registration: June 15, 2018; study period: between October 2017 and February 2018).

Pharmacokinetic Drug Interaction Between Raloxifene and Cholecalciferol in Healthy Volunteers.

Osteoporosis is a common skeletal disorder, often leading to fragility fracture. Combination therapy with raloxifene, a selective estrogen receptor modulator, and cholecalciferol (vitamin D3 ) has been proposed to improve the overall efficacy and increase compliance of raloxifene therapy for postmenopausal osteoporosis. To our knowledge, there has been no report of any study on the pharmacokinetic interaction between raloxifene and cholecalciferol. This study aimed to evaluate the possible pharmacokinetic interactions between raloxifene and cholecalciferol in healthy adult male Korean volunteers. Twenty subjects completed this open-label, randomized, single-dose, 3-period, 6-sequence, crossover phase 1 study with a 14-day washout period. Serial blood samples were collected from 20 hours before dosing to 96 hours after dosing. The plasma concentrations of raloxifene and cholecalciferol were determined using a validated method for high-performance liquid chromatography with tandem mass spectrometry. The geometric mean ratios (90%CIs) for area under the plasma concentration-time curve from time 0 to the last quantifiable time point and maximum plasma concentration of raloxifene with or without cholecalciferol were 1.02 (0.87-1.20) and 0.87 (0.70-1.08), respectively. For baseline-corrected cholecalciferol, geometric mean ratios (90%CIs) of area under the plasma concentration-time curve from time 0 to the last quantifiable time point and maximum plasma concentration with or without raloxifene were 1.01 (0.93-1.09) and 0.99 (0.92-1.06), respectively. Concurrent treatment with raloxifene and cholecalciferol was generally well tolerated. These results suggest that raloxifene and cholecalciferol have no clinically relevant pharmacokinetic drug-drug interactions when administered concurrently. All treatments were well tolerated, with no serious adverse events.

A randomized, open-label, single-dose, two-way crossover study to assess the pharmacokinetics between two tablets of fixed-dose combination formulation with raloxifene and cholecalciferol and concomitant administration of each agents in healthy male volunteers.

A new fixed-dose combination (FDC) formulation of raloxifene 60 mg and cholecalciferol 800 IU was developed to improve the medication compliance and overall efficacy of raloxifene treatment in postmenopausal osteoporosis patients. The aim of this study was to compare the pharmacokinetics between two tablets of FDC formulation of raloxifene/cholecalciferol and the two products administered concomitantly at respective doses. This randomized, open-label, single-dose, two-treatment, two-way crossover study included 46 volunteers. During each treatment period, subjects received the test formulation (FDC formulation containing raloxifene and cholecalciferol) or the reference formulation (co-administration of raloxifene and cholecalciferol), with a 14-d washout period. Serial blood samples were collected periodically over 96 hours after drug intake. In total, 46 subjects completed the study. The geometric mean ratios and its 90% confidence intervals of the FDC to the single agents for the area under the concentration-time curve from zero to the last quantifiable time point and the maximum plasma concentration met the regulatory criteria for bioequivalence: 1.1364 (1.0584-1.2201) and 1.1010 (0.9945-1.2188) for raloxifene and 1.0266 (0.9591-1.0989) and 1.0354 (0.9816-1.0921) for baseline-corrected cholecalciferol, respectively. Both formulations were well tolerated. No significant differences was observed in the incidence of adverse events between the two treatments. It was concluded that two tablets of the newly developed FDC formulation of raloxifene and cholecalciferol and the corresponding two agents administered concomitantly at respective doses were bioequivalent. Trial Registration: ClinicalTrials.gov Identifier: NCT03010267.

Rapid Interference-free Analysis of ß-Lapachone in Clinical Samples Using Liquid Chromatography-Mass Spectrometry for a Pharmacokinetic Study in Humans.

A rapid analytical method developed for the analysis of ß-lapachone in in vitro samples could not be directly applied to the analysis of clinical samples because of interference from unknown substances. Here, we developed and validated a rapid interference-free analytical method to accurately determine ß-lapachone levels in human plasma using liquid chromatography-tandem mass spectrometry. First, we achieved the baseline-separation of ß-lapachone from any interfering substances within a total run time of 4 min by adjusting the eluent strength of the mobile phase. Second, precursor-ion scanning revealed the identity of the interfering substances. Sulfonate- or glucuronide-conjugated metabolites were converted to ß-lapachone in an electrospray ion source, causing interference. In a method validation study, calibration curves for ß-lapachone in human plasma were linear over a concentration range from 0.5 to 200 ng/mL (r > 0.999), and the lower limit of quantification was 0.5 ng/mL. The other validation parameters, including intra- and interday accuracy and precision, were acceptable with a coefficient of variation less than 10% (n = 5). The validated analytical method was successfully applied to a pharmacokinetic study of a single, oral dose of 100 mg MB12066 (a clinical form of ß-lapachone) in healthy volunteers.

Evaluation of the Pharmacokinetic Drug-Drug Interaction between Micronized Fenofibrate and Pitavastatin in Healthy Volunteers.

Dyslipidemia is a major risk factor for development of atherosclerosis and cardiovascular disease (CVD). Effective lipid-lowering therapies has led to CVD risk reduction. This study evaluated the possible pharmacokinetic interactions between fenofibrate, a peroxisome proliferators-activated receptors α agonist, and pitavastatin, a 3-hydoxy-3-methylglutaryl-coenzyme A reductase inhibitor, in healthy Korean subjects. The study design was an open-label, randomized, multiple-dose, three-period, and six-sequence crossover study with a 10-day washout in 24 healthy volunteers. It had three treatments: 160 mg of micronized fenofibrate once daily for 5 days; 2 mg of pitavastatin once daily for 5 days; and 160 mg of micronized fenofibrate with 2 mg of pitavastatin for 5 days. Serial blood samples were collected at scheduled intervals for up to 48 h after the last dose in each period to determine the steady-state pharmacokinetics of both drugs. Plasma concentrations of fenofibric acid and pitavastatin were measured using a validated high-performance liquid chromatography with the tandem mass spectrometry method. A total of 24 subjects completed the study. Pitavastatin, when co-administered with micronized fenofibrate, had no effect on the Cmax,ss and AUCτ,ss of fenofibric acid. The Cmax,ss and AUCτ,ss of pitavastatin were increased by 36% and 12%, respectively, when co-administered with fenofibrate. Combined treatment with pitavastatin and micronized fenofibrate was generally well tolerated without serious adverse events. Our results demonstrated no clinically significant pharmacokinetic interactions between micronized fenofibrate and pitavastatin when 160 mg of micronized fenofibrate and 2 mg of pitavastatin are co-administered. The treatments were well tolerated during the study, with no serious adverse events.

Pharmacokinetics and bioequivalence of fixed-dose combination of candesartan cilexetil/amlodipine besylate (16/10 mg) versus coadministration of individual formulations in healthy subjects.

This study compared the pharmacokinetics of a fixed-dose combination (FDC) of candesartan (16 mg) and amlodipine (10 mg) versus coadministration of individual formulations to clarify the bioequivalence of the FDC. In this randomized, open-label, single-dose, 2-treatment, 2-way crossover study, healthy Korean volunteers received a single dose of candesartan (16 mg) with amlodipine (10 mg) as either an FDC or single agents concomitantly administered, with a 2-week washout period. Serial blood samples were collected up to 72 hours after dosing for each treatment period, and plasma concentrations of candesartan and amlodipine were measured using a validated liquid chromatography-tandem mass spectrometry method. A total of 39 subjects completed the study. The geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for the area under the plasma concentration-time curve from time 0 to the last measurement (AUC0-t) and the peak plasma concentration (Cmax) for candesartan were 1.0182 (0.9562-1.0841) and 0.9492 (0.8726-1.0324), respectively. The GMR and 90% CI for the AUC0-t and Cmax for amlodipine were 1.0552 (1.0255-1.0857) and 1.0668 (1.0259-1.1094), respectively. In conclusion, the new FDC formulation of candesartan (16 mg) and amlodipine (10 mg) was bioequivalent to the concomitant administration of single agents. A single dose of candesartan/amlodipine as the FDC or as single agents was well tolerated. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02988362.

A Pharmacokinetic Drug Interaction Between Fimasartan and Linagliptin in Healthy Volunteers.

OBJECTIVE: Fimasartan, an angiotensin II type 1 receptor blocker, and linagliptin, a dipeptidyl-peptidase-4 inhibitor, are frequently coadministered to treat patients with hypertension and diabetes, respectively. This study sought to evaluate the pharmacokinetic interactions between fimasartan and linagliptin after co-administration in healthy Korean subjects. METHODS: The overall study was divided into two separate parts, with each part designed as an open-label, multiple-dose, two-period, and single-sequence study. In Part A, to investigate the effect of linagliptin on fimasartan, 25 subjects received 120 mg fimasartan alone once daily for seven days during Period I, and 120 mg fimasartan with 20 mg linagliptin for seven days during Period II. In Part B, to examine the effect of fimasartan on linagliptin, 12 subjects received only linagliptin once daily for seven days during Period I, followed by concomitant administration of fimasartan for seven days during Period II, at the same doses used in Part A. Serial blood samples were collected at scheduled intervals for up to 24 h after the last dose to determine the steady-state pharmacokinetics of both drugs. RESULTS: Thirty-six subjects completed the study. The geometric mean ratio and 90% confidence intervals for maximum plasma concentration at steady state (Cmax,ss) and area under the concentration-time curve at steady state (AUCτ,ss) of fimasartan with or without linagliptin were 1.2633 (0.9175-1.7396) and 1.1740 (1.0499-1.3126), respectively. The corresponding values for Cmax,ss and AUCτ,ss of linagliptin with or without fimasartan were 0.9804 (0.8480-1.1336) and 0.9950 (0.9322-1.0619), respectively. A total of eight adverse events (AEs) were reported and the incidence of AEs did not increase significantly with co-administration of the drugs. CONCLUSION: Our results suggest that there are no clinically significant pharmacokinetic interactions between fimasartan and linagliptin when co-administered. Treatments were well tolerated during the study, with no serious adverse effects. CLINICAL TRIAL REGISTRY: http://clinicaltrials.gov, NCT03250052.

Tolerability and pharmacokinetics of ginsenosides Rb1, Rb2, Rc, Rd, and compound K after single or multiple administration of red ginseng extract in human beings.

BACKGROUND: We investigated the tolerability and pharmacokinetic properties of various ginsenosides, including Rb1, Rb2, Rc, Rd, and compound K, after single or multiple administrations of red ginseng extract in human beings. METHODS: Red ginseng extract (dried ginseng > 60%) was administered once and repeatedly for 15 days to 15 healthy Korean people. After single and repeated administration of red ginsengextract, blood sample collection, measurement of blood pressure and body temperature, and routine laboratory test were conducted over 48-h test periods. RESULTS: Repeated administration of high-dose red ginseng for 15 days was well tolerated and did not produce significant changes in body temperature or blood pressure. The plasma concentrations of Rb1, Rb2, and Rc were stable and showed similar area under the plasma concentration-time curve (AUC) values after 15 days of repeated administration. Their AUC values after repeated administration of red ginseng extract for 15 days accumulated 4.5- to 6.7-fold compared with single-dose AUC. However, the plasma concentrations of Rd and compound K showed large interindividual variations but correlated well between AUC of Rd and compound K. Compound K did not accumulate after 15 days of repeated administration of red ginseng extract. CONCLUSION: A good correlation between the AUC values of Rd and compound K might be the result of intestinal biotransformation of Rb1, Rb2, and Rc to Rd and subsequently to compound K, rather than the intestinal permeability of these ginsenosides. A strategy to increase biotransformation or reduce metabolic intersubject variability may increase the plasma concentrations of Rd and compound K.

Pharmacokinetic and bioequivalence study between two formulations of S-1 in Korean gastric cancer patients.

PURPOSE: S-1 is an oral fluoropyrimidine anticancer drug consisting of the 5-fluorouracil prodrug tegafur combined with gimeracil and oteracil. The purpose of this study was to evaluate the pharmacokinetic (PK), bioequivalence, and safety of a newly developed generic formulation of S-1 compared with the branded reference formulation, in Korean gastric cancer patients. METHODS: This was a single-center, randomized, open-label, single-dose, two-treatment, two-way crossover study. Eligible subjects were randomly assigned in a 1:1 ratio to receive the test formulation or reference formulation, followed by a one-week washout period and administration of the alternate formulation. Serial blood samples were collected at 0 hrs (predose), 0.25, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, and 48 hrs after dosing in each period. The plasma concentrations of tegafur, 5-FU, gimeracil, and oteracil were analyzed using a validated liquid chromatography-tandem mass spectrometry method. The PK parameters were calculated using a non-compartmental method. RESULTS: In total, 29 subjects completed the study. All of the 90% confidence intervals (CIs) of the geometric mean ratios (GMRs) fell within the predetermined acceptance range. No serious adverse events were reported during the study. CONCLUSION: The new S-1 formulation met the Korean regulatory requirement for bioequivalence. Both S-1 formulations were well tolerated in all subjects.Clinical trial registry: https://cris.nih.go.kr CRIS KCT0003855.

Pharmacokinetic Drug Interactions Between Amlodipine, Valsartan, and Rosuvastatin in Healthy Volunteers.

INTRODUCTION: Amlodipine, valsartan, and rosuvastatin are among the medications widely coadministered for the treatment of hyperlipidemia accompanied by hypertension. The aim of this study was to investigate the possible pharmacokinetic drug-drug interactions between amlodipine, valsartan, and rosuvastatin in healthy Korean male volunteers. METHODS: In this phase 1, open-label, multiple-dose, two-part, two-period, fixed-sequence study, the enrolled subjects were randomized into two parts (A and B). In part A (n = 32), each subject received one fixed-dose combination (FDC) tablet of amlodipine/valsartan 10 mg/160 mg alone for 10 consecutive days in period I, and the same FDC for 10 days with concomitant 7-day administration of 20 mg rosuvastatin in period II. In part B (n = 25), each subject received rosuvastatin alone for 7 days in period I, and the FDC for 10 days with concomitant 7-day administration of rosuvastatin in period II. In both parts, there was a 12-day washout between periods. Serial blood samples were collected for up to 72 h for amlodipine and rosuvastatin, and for up to 48 h for valsartan after the last dose of each period. The plasma concentrations of amlodipine, valsartan, and rosuvastatin were determined by using liquid chromatography-tandem mass spectrometry. RESULTS: Fifty-seven subjects were enrolled; 30 and 25 subjects completed part A and part B, respectively. The geometric mean ratios and 90% confidence intervals for the maximum plasma concentration at steady state (Cmax,ss) and the area under the plasma concentration-time curve over the dosing interval at steady state (AUCτ,ss) were 0.9389 (0.9029-0.9763) and 0.9316 (0.8970-0.9675) for amlodipine, 0.7698 (0.6503-0.9114) and 0.7888 (0.6943-0.8962) for valsartan, and 0.9737 (0.8312-1.1407) and 0.9596 (0.8826-1.0433) for rosuvastatin, respectively. Of the 57 subjects enrolled in this study, 10 subjects experienced 13 adverse events (AEs); no severe or serious AEs were reported. CONCLUSION: When amlodipine, valsartan, and rosuvastatin were coadministered to healthy volunteers, the pharmacokinetic exposure to valsartan was decreased, but no change in exposure to amlodipine and rosuvastatin occurred. All treatments were well tolerated. CLINICAL TRIAL REGISTRATION: https://cris.nih.go.kr CRIS KCT0001660. FUNDING: KyungDong Pharmaceutical Corp. Ltd., Seoul, Republic of Korea.

Urinary metabolomic profiling for noninvasive diagnosis of acute T cell-mediated rejection after kidney transplantation.

To improve early renal allograft function, it is important to develop a noninvasive diagnostic method for acute T cell-mediated rejection (TCMR). This study aims to explore potential noninvasive urinary biomarkers to screen for acute TCMR in kidney transplant recipients (KTRs) using untargeted metabolomic profiling. Urinary metabolites, collected from KTRs with stable graft function (STA) or acute TCMR episodes, were analyzed using liquid chromatography-mass spectrometry (LC-MS). Multivariate statistical analyses were performed to discriminate differences in urinary metabolites between the two groups. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of potential urinary biomarkers. Statistical analysis revealed the differences in urinary metabolites between the two groups and indicated several statistically significant metabolic features suitable for potential biomarkers. By comparing the retention times and mass fragmentation patterns of the chemicals in metabolite databases, samples, and standards, six of these features were clearly identified. ROC curve analysis showed the best performance of the training set (area under the curve value, 0.926; sensitivity, 90.0%; specificity, 84.6%) using a panel of five potential biomarkers: guanidoacetic acid, methylimidazoleacetic acid, dopamine, 4-guanidinobutyric acid, and L-tryptophan. The diagnostic accuracy of this model was 62.5% for an independent test dataset. LC-MS-based untargeted metabolomic profiling is a promising method to discriminate between acute TCMR and STA groups. Our model, based on a panel of five potential biomarkers, needs to be further validated in larger scale studies.