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Frequent changes in economic policy pose challenges to normal business production and operations. However, little is known about the non-market strategies adopted by firms in emerging economies, such as China, in response to economic policy uncertainty. This study proposes that firms in China respond to high levels of economic policy uncertainty by increasing philanthropic donations and bribery. In addition, this study argues that private firms and state-owned firms implement different strategies to cope with economic policy uncertainty. Specifically, the study suggests that state-owned enterprises (SOEs) are more likely, than non-SOEs, to respond to economic policy uncertainty by increasing corporate philanthropy, and less likely to respond by increasing expenditure on bribes. This study obtained empirical evidence to support these views, based on an analysis of a dataset of 2,904 listed Chinese firms from 2008 to 2019. [ABSTRACT FROM AUTHOR]

With the proposal of the carbon neutrality target, China's attention to carbon emissions has been further enhanced. Effective prediction of future carbon emissions is important for the formulation of carbon neutralization target and action plans in the region. Many factors affecting carbon emissions, cause their development trends may be nonlinear. To forecast the carbon emissions of coal and natural gas in the industrial sector more accurately, a new MGM(1,m,N|γ) model considering nonlinear characteristics is proposed in this paper. The new model introduces power function γ as nonlinear parameter, and the γ value is solved by nonlinear constraint function. We further deduce the simulation and prediction formula and then apply the improved model to the carbon emission forecast. The comparisons show that the nonlinear parameters can modify the trend of sequences and improve the prediction accuracy, which verifies the validity of the model. Finally, according to the influencing factors and forecast results, this paper analyzes the causes of high carbon emissions and puts forward reasonable suggestions for China's carbon governance. [ABSTRACT FROM AUTHOR]

Objectives: Polymyxin B is a last-line antibiotic for multidrug-resistant gram-negative bacterial infections. However, limited safety and pharmacokinetic information is available. We investigated the safety and pharmacokinetics of intravenous polymyxin B in healthy subjects.Methods: An open-label, single-dose clinical trial was conducted in healthy Chinese subjects. Polymyxin B (sulphate) was administered intravenously at 0.75 or 1.5 mg/kg (n = 10 per dose, 5 males and 5 females) to examine the safety and pharmacokinetics.Results: One female subject in the 1.5-mg/kg group discontinued due to abdominal pain during administration. The most frequently reported adverse events were perioral paraesthesia, dizziness, and numbness of extremities (7/10 subjects in the 0.75-mg/kg group, all subjects in the 1.5-mg/kg group). All neurotoxicity-related events dissipated without treatment within a maximum of 23 h. Notably, abdominal pain (3/5) and vulvar pruritus (2/5), colpitis (2/5) or abnormal uterine bleeding (1/5) were reported in female subjects receiving the 1.5-mg/kg dose. In the 0.75-mg/kg group, the total clearance, volume of distribution and half-life of polymyxin B were 0.028±0.002 L/h/kg, 0.219±0.023 L/kg and 5.44±0.741 h, respectively; similar values were observed in the 1.5-mg/kg group. Urinary recovery was 3.7 ± 1.1% and 8.1 ± 1.3% in the 0.75- and 1.5-mg/kg groups, respectively. Population pharmacokinetics of polymyxin B was consistent with a three-compartment model. The clearance and distribution of the central compartment were 0.027 L/h/kg and 0.071 L/kg, respectively.Conclusions: This study is the first to examine the safety and pharmacokinetics of polymyxin B in healthy subjects. Our results highlight that acute toxicity is a dose-limiting factor for intravenous polymyxin B. [ABSTRACT FROM AUTHOR]

Collaborative innovation has received the attention of management scholars for decades. The primary focus of our research is to explore the mechanisms that drive innovation catch-up of latecomers in an emerging economy through research and development collaborations (i.e., academic and industrial collaborations). Using a sample of 1,066 firms in a high-tech cluster in China, we find that collaborative innovation strategy has an inverse U-shaped effect on a firm's innovation performance. In addition, the relationship between collaborative innovation strategy and innovation performance is positively moderated by absorptive capacity © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Porphyra haitanensis (T. J. Chang & B. F. Zheng) is an important economic alga found off the southern coast of China. It has evolved a strong tolerance against stress, which is an important survival characteristic. Cyclophilin has been shown to be involved in the stress response of plants and algae. To investigate the tolerance against stress in Porphyra, we isolated the cyclophilin Ph CYP18 gene (Accession number ) and measured its expression over different generations and stress conditions. In P. haitanensis, cyclophilin Ph CYP18 accumulated more in the filamentous sporophyte generation than in the blade gametophyte generation. This difference was thought to be due to harsh environments and a gene dosage effect. It has been found, however, that Ph CYP18 expression was dysregulated in blades under high salt stress, strong irradiance stress and multifactorial stress compared to blades under normal conditions. Moreover, the changes were not linearly related to the degree of stress. It was therefore thought that Ph CYP18 actively responded to stress situations and induced strong stress tolerance, which is evident in P. haitanensis. [ABSTRACT FROM AUTHOR]

Obstructive hypertrophic cardiomyopathy (oHCM) is a subtype of HCM characterized by left ventricular outflow tract obstruction resulting from cardiac muscle hypertrophy and anatomic alterations in the mitral valve and apparatus. Mavacamten, a cardiac myosin inhibitor metabolized primarily by CYP2C19 in the liver, is the first and only targeted medication approved for the treatment of symptomatic New York Heart Association (NYHA) class II-III oHCM. Previous pharmacokinetic (PK) results of mavacamten in healthy Caucasian, Japanese, and Asian participants demonstrated that mavacamten exposure was affected by CYP2C19 metabolism status. This open-label, parallel-group, phase I trial aimed to determine the PK and safety of mavacamten in healthy Chinese participants with different CYP2C19 genotypes. The primary outcome was to define the PK of mavacamten in healthy Chinese participants; the secondary outcome was to examine safety and tolerability. After a single oral dose of 15 or 25 mg mavacamten in fasted healthy adult Chinese individuals, C max was reached within a median T max of 0.6-1.5 h, indicating rapid absorption. Inter-individual variability was moderate, and individuals carrying non-functional CYP2C19 alleles (*2/*2, *3/*3, or *2/*3) exhibited longer half-life and increased total exposure. After stratification of CYP2C19 genotypes, total mavacamten exposures were similar among different ethnic groups when compared with prior PK studies. No significant adverse events were observed in this study. Single oral administration of mavacamten at 15 mg was well tolerated across all CYP2C19 genotypes, and 25 mg dose was well tolerated in healthy participants with CYP2C19 genotypes UM/RM/NM. The PK profile of mavacamten in the healthy Chinese population was consistent with that in other healthy populations., (© 2024 The Author(s). Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Background: Vupanorsen is a GalNAc 3 -conjugated antisense oligonucleotide targeting angiopoietin-like 3 (ANGPTL3) mRNA shown to reduce atherogenic lipoproteins in individuals with dyslipidemia., Objectives: The aim of this study was to satisfy Chinese regulatory requirements and support ethnic sensitivity assessment by evaluating pharmacokinetics (PK), pharmacodynamics (PD), and safety of vupanorsen in healthy Chinese adults with elevated triglycerides (TG)., Methods: In this phase I, parallel-cohort, open-label study, 18 Chinese adults with elevated fasting TG (≥ 90 mg/dL) were randomized 1:1 to receive a single subcutaneous dose of vupanorsen 80 mg or 160 mg. PK parameters, PD markers (including ANGPTL3, TG, non-high-density lipoprotein cholesterol [non-HDL-C]), and safety were assessed., Results: Absorption of vupanorsen was rapid (median time to maximum concentration [T max ]: 2.0 h for both doses), followed by a multiphasic decline (mean terminal half-life 475.9 [80 mg] and 465.2 h [160 mg]). Exposure (area under curve [AUC] and maximum plasma concentration [C max ]) generally increased in a greater than dose-proportional manner from 80 mg to 160 mg. Time-dependent reductions in ANGPTL3 and lipid parameters were observed. Mean percentage change from baseline for the 80-mg and 160-mg doses, respectively, were - 59.7% and - 69.5% for ANGPTL3, - 41.9% and - 52.5% for TG, and - 23.2% and - 25.4% for non-HDL-C. No serious or severe adverse events (AEs), deaths, or discontinuations due to AEs were reported. Three participants experienced treatment-related AEs; all were mild and resolved by end of study., Conclusions: This study provided the first clinical vupanorsen data in China. In Chinese participants with elevated TG, PK and PD parameters were consistent with those reported previously in non-Chinese participants, including in Japanese individuals. No safety concerns were noted., Trial Registration: ClinicalTrials.gov identifier: NCT04916795., (© 2024. The Author(s).)

The objective of this study is to evaluate the pattern of bone mineral density (BMD) in native Jiaxing women, and to investigate their awareness of osteoporosis. A total of 538 native Jiaxing women aged 40 to 60 years were recruited from January 2022 to December 2023 when they had routine examinations in the physical examination center of Jiaxing Maternal and Child Health Hospital. The Chinese version of Osteoporosis Prevention and Cognition Tool was used to evaluate participants' cognitive level of osteoporosis. BMD of participants' lumbar spine (L1-L4) and left hip (Neck/Troch/Ward) was measured by dual-energy X-ray absorptiometry. The mean total score of the awareness about osteoporosis (general knowledge, complications, and prevention) was 22.08 ± 2.74, which was suboptimal. The higher the education level, the higher the score of awareness (P < .01). Medical staff had the highest awareness rate of osteoporosis and the farmer had the lowest. Lumber spine and hip BMD of all sites was significantly decreased with increasing age (P < .001). Premenopausal women had higher BMD than postmenopausal women at all lumbar spine and hip sites (P < .01). The overall frequency of osteoporosis was 10.8% in the lumbar spine, 8.6% in the total hip, and 17.7% in either site. Osteoporosis and osteopenia are highly prevalent among native Jiaxing women but their awareness of osteoporosis is inadequate. To reduce the prevalence of osteoporosis, especially among the unemployed, we should carry out effective health education through multimedia to raise their awareness of osteoporosis. In addition, menopausal hormone therapy should also be considered in menopausal women., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Introduction: 9MW1411 is a humanised monoclonal antibody against Staphylococcus aureus alpha-toxin. The safety, pharmacokinetics (PK) and immunogenicity of 9MW1411 should be characterised in humans before further clinical development., Methods: A single-centre, randomised, double-blind, placebo-controlled phase I clinical study was conducted in humans for the first time. A total of 42 healthy Chinese subjects were randomised to receive a single ascending dose of 9MW1411 (200, 600, 1500, 3000 or 5000 mg) or placebo. Safety, PK parameters and anti-drug antibody (ADA) were analysed. Monte Carlo simulations (MCS) were performed to predict the probability of target attainment (PTA) after single dose IV administration of 1500, 3000 and 5000 mg of 9MW1411., Results: Thirty-four subjects received 9MW1411, completed the study and were included in data analysis. Five cases of drug-related AEs occurred in four subjects. All the adverse events (AEs) were mild or moderate. The C max , AUC 0-t and AUC 0-∞ of 9MW1411 increased with dose after IV administration of 200 to 5000 mg 9MW1411. The mean C max increased from 85.40 ± 5.43 to 2082.11 ± 343.10 µg/mL and AUC 0-∞ from 29,511.68 ± 5550.91 to 729,985.49 ± 124,932.18 h·µg/mL. The elimination half-life (T 1/2 ) was 19-23 days. 9MW1411 ADA was positive in three subjects. MCS indicated that a single dose of 3000 or 5000 mg 9MW1411 could achieve PTA > 90% for S. aureus., Conclusions: 9MW1411 has shown a good safety profile in healthy Chinese subjects after a single dose up to 5000 mg. A single dose of 3000 mg 9MW1411 is appropriate for use in subsequent studies., (Copyright © 2023. Published by Elsevier Ltd.)

Carbon emission is a common concern of the international community and effectively predicting its future trend is necessary for emission reduction planning. Considering that the change trend of carbon emissions is unstable, more attention should be paid to the correction effect of new information on the development trend. Therefore, based on the traditional MGM(1,m) model, this paper introduces the new information priority operator λ and nonlinear parameter γ to strengthen the role of new information, further constructs three comparison models of MGM(1,m|λ), MGM(1,m|γ) and MGM(1,m|λ,γ).Then we apply the new model to the carbon emission prediction of different regions (cities, countries and continents) and different trends (fluctuating, rising and declining). The results illustrate that the new model has higher prediction accuracy, and adding dynamic parameters is a scientific and practical method to improve the forecasting ability of the grey forecasting model. Finally, we analyze the current situation and future development trend of carbon emissions, and put forward reasonable suggestions., Competing Interests: Declaration of competing interest The authors declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

This study aimed to build a population pharmacokinetic (PopPK) model for contezolid tablet (MRX-I) in healthy subjects and adults with complicated skin and soft-tissue infections (cSSTIs) to further evaluate the efficacy and safety of contezolid and recommend the optimal dosing regimen based on pharmacokinetic/pharmacodynamic (PK/PD) analysis. PopPK analysis was performed using a nonlinear mixed-effects model (NONMEM) to examine the effects of age, body weight, sex, liver and renal functions, albumin, food, dosage strength, and subject type on the PK parameters of contezolid. PK/PD analysis was combined with the MIC of contezolid, clinical/microbiological efficacy, and nonclinical study data. Adverse events (AEs) and study drug-related AEs reported were summarized to examine the relationship between contezolid exposure level and safety measures. A two-compartment model was built. An exponential model was used to describe the interindividual variation. A proportional model was used to describe the intraindividual variation of PK parameters. Good clinical and microbiological efficacy are expected for the infections caused by S. aureus when contezolid is administered at 600 mg or 800 mg every 12 h (q12h). The area under the concentration-time curve from 0 to 24 h at steady state and maximum concentration of drug in serum at steady state of contezolid did not show significant association with the incidence of any AE. The dosing regimen of contezolid at 800 mg q12h administered postprandially for 7 to 14 days is expected to achieve satisfactory clinical and microbiological efficacy in cSSTIs, which is slightly better than that of 600 mg contezolid. This administration has been added to the prescribing information of contezolid tablets.

While video games are one of the most common online entertainment activities, Internet gaming disorder (IGD) in adolescents is a critical issue that has become a widely raised public concern. This one-year longitudinal study examined the reciprocal associations between shyness, depression, and IGD symptoms in a sample of Chinese adolescents. A fully cross-lagged panel design was used, in which shyness, depression, and IGD symptoms were assessed at two time points with an interval of one year (T1 and T2). A total of 1,047 junior high school students (504 boys; 543 girls; mean age = 12.45 years) participated in the study. Cross-lagged analysis results indicated a significant positive correlation between shyness, depression, and IGD symptoms, as well as a dynamic and bidirectional relationship between them. Specifically, T1 shyness positively predicted T2 depression symptoms (β = 0.167, p < 0.001), T1 depression symptoms positively predicted T2 shyness (β = 0.141, p < 0.01), and T1 IGD symptoms positively predicted T2 depression symptoms (β = 0.073, p < 0.05). In addition to these findings, gender differences were identified in shyness (T1 and T2), IGD symptoms (T1 and T2), and depression symptoms (T2). The results also indicated that shyness and symptoms of depression could significantly positively predict each other over time, and IGD symptoms could significantly predict depression symptoms. However, depression symptoms could not significantly predict IGD symptoms over the one-year study period, and there was no significant two-way prediction between shyness and IGD symptoms. Thus, this study reveals possible reciprocal associations between shyness, depression, and IGD symptoms in Chinese adolescents and provides insights and suggestions for reducing online gaming addiction among adolescents from the perspective of shyness and depression., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The objectives of this phase I study are to assess the safety, tolerability, and pharmacokinetics (PKs) of RO7049389 in healthy Chinese volunteers (HVs) and evaluate potential ethnic differences in the safety and PKs using data from this study and the first-in-human study (in which most of the HVs were non-Asian). HVs randomly received a single dose of 200-600 mg of RO7049389 or a placebo in a single ascending dose (n = 28) or multiple doses of 200-400 mg of RO7049389 or a placebo in multiple ascending doses (n = 24). Safety and tolerability were monitored throughout the study. Serial blood samples were collected for PK analysis. RO7049389 was safe and well-tolerated in the HVs. The time to maximum concentration ranged from 1.5 to 3.0 h, and terminal half-life ranged from 3.66 to 14.6 h. A single dose of 200-600 mg and multiple doses of 200-400 mg exhibited nonlinear PKs. In general, the safety profiles were comparable between non-Asian and Asian HVs, but the plasma exposure of RO7049389 in Chinese HVs was higher than that in non-Asian HVs. The data generated from this study will provide guidance for future clinical studies on RO7049389 in Chinese/Asian patients with hepatitis B virus., (© 2021 Roche R&D Center China Ltd. Clinical and Translational Science published by Wiley Periodicals LLC on behalf of the American Society for Clinical Pharmacology and Therapeutics.)

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread rapidly worldwide. This study is the first to report the tolerability, safety, pharmacokinetics (PK), and immunogenicity of a recombinant human anti-SARS-CoV-2 monoclonal antibody, etesevimab (CB6, JS016, LY3832479, or LY-CoV016), in healthy adults. This paper describes a randomized, double-blind, placebo-controlled, phase 1 study. A total of 40 participants were enrolled to receive a single intravenous dose of either etesevimab or placebo in one of four sequential ascending intravenous dose cohorts. All 40 participants completed the study. Seventeen (42.5%) participants experienced 22 treatment emergent adverse events (TEAEs) that were drug-related, and the rates of these TEAEs among different dose cohorts were numerically comparable. No difference was observed between the combined etesevimab group and the placebo group. The exposure after etesevimab infusion increased in an approximately proportional manner as the dose increased from 2.5 to 50 mg/kg. The elimination half-life ( t 1/2 ) value did not differ among different dose cohorts and was estimated to be around 4 weeks. Etesevimab was well tolerated after administration of a single dose at a range of 2.5 mg/kg to 50 mg/kg in healthy Chinese adults. The PK profiles of etesevimab in healthy volunteers showed typical monoclonal antibody distribution and elimination characteristics. (This study has been registered at ClinicalTrials.gov under identifier NCT04441918.).

Contezolid (MRX-I), a new oxazolidinone, is an antibiotic in development for treating complicated skin and soft tissue infections caused by resistant Gram-positive bacteria. This was a thorough QT study conducted in 52 healthy subjects who were administered oral contezolid at a therapeutic (800 mg) dose, a supratherapeutic (1,600 mg) dose, placebo, and oral moxifloxacin at 400 mg in four separate treatment periods. The pharmacokinetic profile of contezolid was also evaluated. Time point analysis indicated that the upper bounds of the two-sided 90% confidence interval (CI) for placebo-corrected change-from-baseline QTc (ΔΔQTc) were <10 ms for the contezolid therapeutic dose at each time point. The upper bound of the 90% CI for ΔΔQTc was slightly more than 10 ms with the contezolid supratherapeutic dose at 3 and 4 h postdose, and the prolongation effect on the QT/QTc interval was less than that of the positive control, moxifloxacin, at 400 mg. At 3 and 4 h after the moxifloxacin dose, the moxifloxacin group met the assay sensitivity criteria outlined in ICH Guidance E14 by having a lower confidence bound of ≥5 ms. The results of a linear exposure-response model which were similar to that of a time point analysis demonstrated a slightly positive relationship between contezolid plasma levels and ΔQTcF interval with a slope of 0.227 ms per mg/liter (90% CI, 0.188 to 0.266). In summary, contezolid did not prolong the QT interval at a therapeutic dose and may have a slight effect on QT interval prolongation at a supratherapeutic dose., (Copyright © 2020 American Society for Microbiology.)

Glucocorticoids are the primary anti-inflammatory therapy for asthma, but their effects are characterized by some interindividual variability that might have a genetic basis.We aimed to determine the relationship between pulmonary function change and the variant of the glucocorticoid-induced transcript 1 (GLCCI1) gene in patients with asthma receiving long-term ICS treatment, the association of GLCCI1 genotypes and the level of GLCCI1 expression and cytokines production.A total of 418 patients with asthma, including 25 individuals from 11 families with a history of asthma, were enrolled. The effects of single-nucleotide polymorphisms (SNPs) in GLCCI1 on changes in lung function in response to inhaled glucocorticoids were assessed. The expression levels of GLCCI1 mRNA and cytokines were also measured.The SNP rs37973 in GLCCI1 was independently associated with changes in forced expiratory volume at one second (FEV1) and FEV1%pred. Individuals homozygous for the wild-type allele who had a percent FEV1 change greater than 5% were more common than individuals homozygous for the rare allele. When patients were stratified according to genotype, GLCCI1 expression was enhanced upon administration of low-dose dexamethasone among patients with the rs37973 A allele; however, GG homozygotes required high-dose dexamethasone to achieve enhanced GLCCI1 expression. Furthermore, the levels of some cytokines were significantly reduced after glucocorticoid treatment in individuals with the AA and AG genotypes.The genetic variant rs37973 in GLCCI1 is associated with poorer clinical therapeutic response to inhaled glucocorticoids in a Chinese asthma population., (Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.)

Levornidazole is the levo-isomer of ornidazole with similar anti-anaerobic activity and lower central neurotoxicity compared with ornidazole. This open-label, parallel, randomised, multidose trial was conducted to compare the pharmacokinetics and safety of levornidazole following intravenous (i.v.) infusion 750mg every 24h (q24h) (test group, 12 subjects) versus 500mg every 12h (q12h) (reference group, 12 subjects) for 7 days in healthy Chinese volunteers. Following i.v. infusion for 7 days, the test group showed a 33.8% lower accumulation ratio (AR) and a 45.0% higher volume of distribution of levornidazole than the reference group. The cumulative urinary excretion rate of levornidazole during the 0-72h period (Ae0-72) was 16.6±20.9% in the test group and 24.2±5.7% in the reference group. The metabolite M1/parent and M4/parent ratios were, respectively, 2.18±0.77% and 2.94±0.37% in test group and 3.15±1.09% and 3.18±0.34% in the reference group. The Ae0-72 of M1, M2 and M4 were all <10% in both groups. Both regimens were well tolerated. Drug-related adverse events were generally transient and were mild or moderate in severity. These findings support the recommendation of i.v. infusion of levornidazole 750mg q24h in clinical practice, which shows a lower AR and similar safety compared with the conventional 500mg q12h regimen. [Chinese Clinical Trial Registry identifier: ChiCTR-IPR-14005574.]., (Copyright © 2016 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.)

Background: To identify COPD associated gene susceptibility and lung function in a longitudinal cohort including COPD and subjects who were at risk for developing COPD, and to replicate this in two cross-sectional and longitudinal populations in Chinese Han population., Methods: Three cohorts were recruited in this study, including an 18-year follow-up population (306 COPD and 743 control subjects) in one village in 1992 and it changed to 409 COPD and 611 controls in 2010, a 2 year follow-up study in another village (374 COPD and 377 controls) and another 2 year follow-up one in a city (541 COPD and 560 controls) in 2010. Sixteen candidate single nucleotide polymorphisms (SNPs) were selected for genotyping. Among them, 5SNPs in or near HHIP, 1SNP in IREB2 and 1SNP in FAM13A were previously reported to be associated with COPD susceptibility or lung function decline. And another 9SNPs were selected from HapMap website as HHIP tags. In 2010, totaling 1,324 COPD patients and 1,548 healthy controls were finally included in our genetic susceptibility analyses., Results: We identified two new regions showing an association with COPD susceptibility in the Human Hedgehog interacting protein (HHIP) rs11100865 and rs7654947, and we confirmed that the family with sequence similarity 13 member A gene (FAM13A) rs7671167 was associated with the development of COPD in Chinese Han population. And the HHIP rs7654947 and FAM13A rs7671167 were associated with lung function decline, and this result was replicated in other two populations., Conclusions: These results suggest an important role of the HHIP and FAM13A regions as genetic risk factors for COPD development and lung function decline in Chinese Han population. Future research on these genes should focus on the molecular mechanisms of these genes on developing COPD and creating therapies to alleviate reduced lung function.

Nemonoxacin (TG-873870) is a novel C-8-methoxy nonfluorinated quinolone with higher activity than ciprofloxacin, levofloxacin and moxifloxacin against Gram-positive pathogens including methicillin-susceptible or methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae with various resistant phenotypes. A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated to determine the concentration of nemonoxacin in human plasma and urine. Protein precipitation and liquid-liquid extraction were employed for plasma and urine sample preparations, respectively, and extract was then injected into the system. Separation was performed on a C(18) reversed-phase column using acetonitrile-0.1% formic acid as a mobile phase. Both analyte and internal standard (gatifloxacin) were determined using electrospray ionization and the MS data acquisition via the selected reaction monitoring in positive-ion mode. The lower limit of quantification was 5 ng/mL and the calibration curves were linear in the concentration range of 5-1000 ng/mL. The accuracy, precision, selectivity, linearity, recovery, matrix effect and stability were validated for TG-873870 in human plasma and urine. The method was successfully applied to a pharmacokinetic study enrolling 12 healthy Chinese volunteers administered nemonoxacin malate capsules., (Copyright © 2012 John Wiley & Sons, Ltd.)

Background: Nemonoxacin, a novel C-8-methoxy non-fluorinated quinolone, is currently being developed in oral and intravenous formulations. It exhibits potent antibacterial activities against Gram-positive, Gram-negative and atypical pathogens, especially methicillin-resistant Staphylococcus aureus. The first-in-human study of a nemonoxacin capsule was conducted in a Western population. This current study was the first investigation on the clinical pharmacokinetics (PK) of nemonoxacin in a Chinese population, and was designed to determine PK data in a Chinese population and investigate the dose regimen for future clinical use., Objective: The objective of this study was to evaluate the PK profile of nemonoxacin as well as its safety and tolerability in healthy Chinese volunteers following single and multiple oral doses., Methods: The first part of the study was a double-blind, placebo-controlled, sequential ascending single-dose safety and tolerability study. In each cohort, two subjects received a placebo and six received single oral doses of nemonoxacin 125, 250, 500, 750 or 1000 mg. In the second part, the single-dose PK study, three dose levels (250, 500 and 750 mg) of nemonoxacin were administered orally to 12 healthy Chinese volunteers (male : female = 1 : 1) under fasting conditions in a crossover manner. The same volunteers received orally an additional dose of 500 mg under fed conditions after a 7-day washout. In the third part, the multiple-dose PK study, 24 subjects received 500 or 750 mg of nemonoxacin orally once daily for 10 consecutive days. Within each cohort, 12 subjects (male : female = 1 : 1) received the same dose level of nemonoxacin under fasting conditions. The PK profiles, safety and tolerability, and food and sex effects were evaluated., Results: No severe or serious adverse events (AEs) occurred in this study, and no clinically significant abnormalities were noted in the vital signs or on physical examination. Notable AEs, mainly nausea and rash with or without pruritus, were mild and resolved spontaneously. Most laboratory AEs were mild and transient and the subjects recovered without treatment. Nemonoxacin was found to be rapidly absorbed, with peak plasma concentrations (C(max)) attained 1-2 hours after administration. The C(max) and area under the concentration-time curve from time zero to infinity (AUC(∞)) were dose-proportional after single oral doses. The elimination half-life was 10-12 hours. Nemonoxacin was excreted primarily in urine, with a recovery of intact nemonoxacin of 60-70% of the dose over 72 hours. Food had a significant effect on the rate and extent of absorption (p < 0.001), increasing the time to reach C(max) from 1.14 to 3.64 hours and reducing C(max) by 34% and AUC(∞) by 18%, while a sex effect was not found. C(max) and AUC(∞) were similar between the single-dose and multiple-dose PK studies. The multiple-dose PK data suggested no drug accumulation in healthy subjects., Conclusion: Nemonoxacin exhibited a linear PK profile in the 250-750 mg dose range with moderate food effects. There was no accumulation following consecutive administration for 10 days. The PK and safety profiles of nemonoxacin in Chinese subjects support evaluation of once-daily dosing in the future development of this agent.