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Kebriaei R, Abdul-Mutakabbir JC, Stamper KC, Lev KL, Rybak MJ. Targeting Dalbavancin Inoculum Effect: Adjunctive Single Dose of Daptomycin. Infect Dis Ther 2023; 12:2485-2494. [PMID: 37798469 PMCID: PMC10600059 DOI: 10.1007/s40121-023-00875-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 09/14/2023] [Indexed: 10/07/2023] Open
Abstract
INTRODUCTION Daptomycin (DAP) has proven to be a viable alternative amid vancomycin resistance; however, the use of DAP post vancomycin treatment has led to the development of DAP non-susceptible (DNS) strains. Dalbavancin (DAL), a novel single-dosed lipoglycopeptide, has shown enhanced activity against highly resistant Staphylococcus aureus strains. However, on the basis of previous reports and our observations, DAL does not demonstrate similar activity at high versus low inoculum levels. Therefore, we hypothesized that addition of DAP even at minimal concentrations (single dose on day 1) will lower the inoculum to the level that can be cleared by dalbavancin. METHODS Isolates from methicillin-resistant S. aureus (MRSA)-infected patients with varying susceptibility profiles were evaluated using broth microdilution methods. Two DNS-VISA strains (vancomycin intermediate resistant S. aureus) and one MRSA strain were further evaluated in a one-compartment PK/PD model using a high starting initial inoculum of 109 CFU/mL as well as low initial inoculum of 107 CFU/mL over 168 h to assess the activity of DAL and DAP monotherapy and in combination. RESULTS Single therapies were not bactericidal when evaluated in the 168 h in vitro one-compartment model with an initial inoculum of 109; however, the combination of DAL plus single dose of DAP resulted in enhanced killing at the end of the 168-h exposure. DAL single therapy caused reduction in colony counts down to detection limit (2 log10 CFU/ml) at a lower inoculum but did not show enhancement (< 2 log10 CFU/ml) at higher initial inoculums (P < 0.01) for all three strains. Similarly, DAP caused initial bacterial reduction up to 4 log10 CFU/ml with regrowth at about 32 h of exposure, which stayed at initial inoculum levels for the duration of the model for all three strains. CONCLUSIONS Dalbavancin inoculum effect is a major issue in bacterial infections with high bacterial loads and the combination of DAL plus single dose of DAP showed promise in eradicating resistant S. aureus strains at high inoculums.
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Affiliation(s)
- Razieh Kebriaei
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA
- P3 Research Laboratory, Division of Outcomes and Translational Sciences, College of Pharmacy, Ohio State University, Columbus, USA
| | - Jacinda C Abdul-Mutakabbir
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA
- Division of Clinical Pharmacy, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
| | - Kyle C Stamper
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA
- Prism Labs, LLC, Walled Lake, MI, USA
| | - Katherine L Lev
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, USA
| | - Michael J Rybak
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA.
- Division of Infectious Diseases, School of Medicine, Wayne State University, Detroit, MI, USA.
- Detroit Receiving Hospital, Detroit, MI, USA.
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Caruso DJ, Palombo EA, Moulton SE, Duggan PJ, Zaferanloo B. Antibacterial and Antibiofilm Activity of Endophytic Alternaria sp. Isolated from Eremophila longifolia. Antibiotics (Basel) 2023; 12:1459. [PMID: 37760755 PMCID: PMC10525891 DOI: 10.3390/antibiotics12091459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/16/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
The threat to public health resulting from the emergence of antimicrobial resistance (AMR) is ever rising. One of the major bacterial pathogens at the forefront of this problem is methicillin-resistant Staphylococcus aureus, or MRSA, for which there is a great need to find alternative treatments. One of the most promising alternatives is endophytic fungi, which were shown to produce a vast array of bioactive compounds, including many novel antibacterial compounds. In this study, two endophytic Alternaria sp., EL 24 and EL 35, were identified from the leaves of Eremophila longifolia. Ethyl acetate (EtOAc) extracts of their culture filtrates were found to inhibit both methicillin-sensitive S. aureus ATCC 25923 and MRSA strains M173525 and M180920. The activity of each extract was shown to be greatly affected by the growth medium, with considerable reductions in minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) observed when tested in tryptic soy broth with glucose (TSBG) compared with Mueller-Hinton broth (MHB). Both extracts displayed significant (p ≤ 0.05) antibiofilm activity against all three S. aureus strains, the greatest of which was that of EL 35, which reduced biofilm formation by M180920 by 72%, while that of EL 24 resulted in a 57% reduction against ATCC 25923. Both extracts also disrupted established biofilms, of which the most effective was EL 35, which reduced the M180920 biofilm by 64%, while EL 24 also performed best against M180920, reducing biofilm by 54%. Gas chromatography-mass spectrometry (GC-MS) analysis of the EL 24 EtOAc extract revealed five known compounds. This study highlights the promise of endophytic fungi from Australian plants as a potential source of substances effective against important bacterial pathogens. Further understanding of the responsible compounds and their mechanisms could lead to the development of treatments effective against MRSA, as well as novel biofilm-resistant biomedical materials, contributing towards reducing the burden of AMR.
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Affiliation(s)
- Daniel J Caruso
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - Enzo A Palombo
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - Simon E Moulton
- Department of Engineering Technologies, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - Peter J Duggan
- CSIRO Manufacturing, Research Way, Clayton, VIC 3168, Australia
- College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
| | - Bita Zaferanloo
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
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Takahashi S, Tsuji Y, Holford N, Ogami C, Kasai H, Kawasuji H, To H, Yamamoto Y. Population Pharmacokinetic Model for Unbound Concentrations of Daptomycin in Patients with MRSA Including Patients Undergoing Hemodialysis. Eur J Drug Metab Pharmacokinet 2023; 48:201-211. [PMID: 36862367 DOI: 10.1007/s13318-023-00820-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2023] [Indexed: 03/03/2023]
Abstract
BACKGROUND AND OBJECTIVE Unbound daptomycin concentrations are responsible for pharmacologically beneficial and adverse effects, although most previous reports have been limited to the use of total concentrations. We developed a population pharmacokinetic model to predict both total and unbound daptomycin concentrations. METHODS Clinical data were collected from 58 patients with methicillin-resistant Staphylococcus aureus including patients undergoing hemodialysis. A total of 339 serum total and 329 unbound daptomycin concentrations were used for model construction. RESULTS Total and unbound daptomycin concentration was explained by a model that assumed first-order distribution with two compartments, and first-order elimination. Normal fat body mass was identified as covariates. Renal function was incorporated as a linear function of renal clearance and independent non-renal clearance. The unbound fraction was estimated to be 0.066 with a standard albumin of 45 g/L and standard creatinine clearance of 100 mL/min. Simulated unbound daptomycin concentration was compared with minimum inhibitory concentration as a measure of clinical effectiveness and exposure-level-related induction of creatine phosphokinase elevation. The recommended doses were 4 mg/kg for patients with severe renal function [creatinine clearance (CLcr) ≤ 30 mL/min] and 6 mg/kg for patients with mild to moderate renal function (CLcr > 30 and ≤ 60 mL/min). A simulation indicated that dose adjusted by body weight and renal function improved target attainment. CONCLUSIONS This population pharmacokinetics model for unbound daptomycin could help clinicians to select the appropriate dose regimen for patients undergoing daptomycin treatment and reduce associated adverse effects.
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Affiliation(s)
- Saki Takahashi
- Department of Medical Pharmaceutics, Faculty of Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan
| | - Yasuhiro Tsuji
- Laboratory of Clinical Pharmacometrics, School of Pharmacy, Nihon University, 7-7-1 Narashinodai, Funabashi, Chiba, 274-8555, Japan.
| | - Nick Holford
- Department of Pharmacology and Clinical Pharmacology, University of Auckland, Auckland, New Zealand
| | - Chika Ogami
- Department of Medical Pharmaceutics, Faculty of Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan
| | - Hidefumi Kasai
- Department of Clinical Pharmacokinetics and Pharmacodynamics, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Hitoshi Kawasuji
- Department of Clinical Infectious Diseases, Toyama University Graduate School of Medicine and Pharmaceutical Sciences, 2630 Sugitani, Toyama, 930-0194, Japan
| | - Hideto To
- Department of Medical Pharmaceutics, Faculty of Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan
| | - Yoshihiro Yamamoto
- Department of Clinical Infectious Diseases, Toyama University Graduate School of Medicine and Pharmaceutical Sciences, 2630 Sugitani, Toyama, 930-0194, Japan
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Pharmacokinetics of Antimicrobials in Children with Emphasis on Challenges Faced by Low and Middle Income Countries, a Clinical Review. Antibiotics (Basel) 2022; 12:antibiotics12010017. [PMID: 36671218 PMCID: PMC9854442 DOI: 10.3390/antibiotics12010017] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 12/25/2022] Open
Abstract
Effective antimicrobial exposure is essential to treat infections and prevent antimicrobial resistance, both being major public health problems in low and middle income countries (LMIC). Delivery of drug concentrations to the target site is governed by dose and pharmacokinetic processes (absorption, distribution, metabolism and excretion). However, specific data on the pharmacokinetics of antimicrobials in children living in LMIC settings are scarce. Additionally, there are significant logistical constraints to therapeutic drug monitoring that further emphasize the importance of understanding pharmacokinetics and dosing in LMIC. Both malnutrition and diarrheal disease reduce the extent of enteral absorption. Multiple antiretrovirals and antimycobacterial agents, commonly used by children in low resource settings, have potential interactions with other antimicrobials. Hypoalbuminemia, which may be the result of malnutrition, nephrotic syndrome or liver failure, increases the unbound concentrations of protein bound drugs that may therefore be eliminated faster. Kidney function develops rapidly during the first years of life and different inflammatory processes commonly augment renal clearance in febrile children, potentially resulting in subtherapeutic drug concentrations if doses are not adapted. Using a narrative review approach, we outline the effects of growth, maturation and comorbidities on maturational and disease specific effects on pharmacokinetics in children in LMIC.
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Tickle ARH, Ledger EVK, Edwards AM. Human serum induces daptomycin tolerance in Enterococcus faecalis and viridans group streptococci. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36748501 DOI: 10.1099/mic.0.001282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Daptomycin is a membrane-targeting lipopeptide antibiotic used in the treatment of infective endocarditis caused by multidrug-resistant Gram-positive bacteria such as Staphylococcus aureus, enterococci and viridans group streptococci. Despite demonstrating excellent in vitro activity and a low prevalence of resistant isolates, treatment failure is a significant concern, particularly for enterococcal infection. We have shown recently that human serum triggers daptomycin tolerance in S. aureus, but it was not clear if a similar phenotype occurred in other major infective endocarditis pathogens. We found that Enterococcus faecalis, Streptococcus gordonii or Streptococcus mutans grown under standard laboratory conditions were efficiently killed by daptomycin, whereas bacteria pre-incubated in human serum survived exposure to the antibiotic, with >99 % cells remaining viable. Incubation of enterococci or streptococci in serum led to peptidoglycan accumulation, as shown by increased incorporation of the fluorescent d-amino acid analogue HADA. Inhibition of peptidoglycan accumulation using the antibiotic fosfomycin resulted in a >tenfold reduction in serum-induced daptomycin tolerance, demonstrating the important contribution of the cell wall to the phenotype. We also identified a small contribution to daptomycin tolerance in E. faecalis from cardiolipin synthases, although this may reflect the inherent increased susceptibility of cardiolipin-deficient mutants. In summary, serum-induced daptomycin tolerance is a consistent phenomenon between Gram-positive infective endocarditis pathogens, but it may be mitigated using currently available antibiotic combination therapy.
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Affiliation(s)
- Alicia R H Tickle
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Rd, London, SW7 2AZ, UK.,Southmead Hospital, Southmead Road, Westbury-on-Trym, Bristol, Avon, BS10 5NB, UK
| | - Elizabeth V K Ledger
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Rd, London, SW7 2AZ, UK
| | - Andrew M Edwards
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Rd, London, SW7 2AZ, UK
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Protein Binding in Translational Antimicrobial Development-Focus on Interspecies Differences. Antibiotics (Basel) 2022; 11:antibiotics11070923. [PMID: 35884177 PMCID: PMC9311574 DOI: 10.3390/antibiotics11070923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/01/2022] [Accepted: 07/05/2022] [Indexed: 12/07/2022] Open
Abstract
Background/Introduction: Plasma protein binding (PPB) continues to be a key aspect of antibiotic development and clinical use. PPB is essential to understand several properties of drug candidates, including antimicrobial activity, drug-drug interaction, drug clearance, volume of distribution, and therapeutic index. Focus areas of the review: In this review, we discuss the basics of PPB, including the main drug binding proteins i.e., Albumin and α-1-acid glycoprotein (AAG). Furthermore, we present the effects of PPB on the antimicrobial activity of antibiotics and the current role of PPB in in vitro pharmacodynamic (PD) models of antibiotics. Moreover, the effect of PPB on the PK/PD of antibiotics has been discussed in this review. A key aspect of this paper is a concise evaluation of PPB between animal species (dog, rat, mouse, rabbit and monkey) and humans. Our statistical analysis of the data available in the literature suggests a significant difference between antibiotic binding in humans and that of dogs or mice, with the majority of measurements from the pre-clinical species falling within five-fold of the human plasma value. Conversely, no significant difference in binding was found between humans and rats, rabbits, or monkeys. This information may be helpful for drug researchers to select the most relevant animal species in which the metabolism of a compound can be studied for extrapolating the results to humans. Furthermore, state-of-the-art methods for determining PPB such as equilibrium dialysis, ultracentrifugation, microdialysis, gel filtration, chromatographic methods and fluorescence spectroscopy are highlighted with their advantages and disadvantages.
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Biomarkers Predicting Tissue Pharmacokinetics of Antimicrobials in Sepsis: A Review. Clin Pharmacokinet 2022; 61:593-617. [PMID: 35218003 PMCID: PMC9095522 DOI: 10.1007/s40262-021-01102-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2021] [Indexed: 02/07/2023]
Abstract
The pathophysiology of sepsis alters drug pharmacokinetics, resulting in inadequate drug exposure and target-site concentration. Suboptimal exposure leads to treatment failure and the development of antimicrobial resistance. Therefore, we seek to optimize antimicrobial therapy in sepsis by selecting the right drug and the correct dosage. A prerequisite for achieving this goal is characterization and understanding of the mechanisms of pharmacokinetic alterations. However, most infections take place not in blood but in different body compartments. Since tissue pharmacokinetic assessment is not feasible in daily practice, we need to tailor antibiotic treatment according to the specific patient’s pathophysiological processes. The complex pathophysiology of sepsis and the ineffectiveness of current targeted therapies suggest that treatments guided by biomarkers predicting target-site concentration could provide a new therapeutic strategy. Inflammation, endothelial and coagulation activation markers, and blood flow parameters might be indicators of impaired tissue distribution. Moreover, hepatic and renal dysfunction biomarkers can predict not only drug metabolism and clearance but also drug distribution. Identification of the right biomarkers can direct drug dosing and provide timely feedback on its effectiveness. Therefore, this might decrease antibiotic resistance and the mortality of critically ill patients. This article fills the literature gap by characterizing patient biomarkers that might be used to predict unbound plasma-to-tissue drug distribution in critically ill patients. Although all biomarkers must be clinically evaluated with the ultimate goal of combining them in a clinically feasible scoring system, we support the concept that the appropriate biomarkers could be used to direct targeted antibiotic dosing.
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8
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Tang WH, Wang SH, Wang CF, Mou Y, Lin MG, Hsiao CD, Liao YD. The lipid components of high-density lipoproteins (HDL) are essential for the binding and transportation of antimicrobial peptides in human serum. Sci Rep 2022; 12:2576. [PMID: 35173253 PMCID: PMC8850444 DOI: 10.1038/s41598-022-06640-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 01/19/2022] [Indexed: 11/26/2022] Open
Abstract
Antimicrobial peptides (AMPs) have been developed for the treatment of bacterial infections, but their applications are limited to topical infections since they are sequestered and inhibited in serum. Here we have discovered that the inhibition of AMPs by human serum was mediated through high-density lipoproteins (HDL) which are known to remove cholesterol from peripheral tissues. The susceptibility of AMPs to HDL varied depending on the degree of hydrophobicity of AMPs and their binding affinities to HDL. The phospholipids, such as phosphatidylcholine, of HDL were essential for AMP-binding. The dynamic binding interactions between AMPs and HDL were mediated through the hydrophobic interactions rather than by ionic strength. Interestingly, some AMPs, such as SMAP29, dissociated from the AMP-HDL complex and translocated to bacteria upon contact, while some AMPs, such as LL37, remained in complex with HDL. These results suggest that HDL binds AMPs and facilitates the translocation of them to the bacteria.
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Affiliation(s)
- Wen-Hung Tang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Shi-Han Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Chiu-Feng Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Yun Mou
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Min-Guan Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan
| | - Chwan-Deng Hsiao
- Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan
| | - You-Di Liao
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan.
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9
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Summerfield SG, Yates JWT, Fairman DA. Free Drug Theory - No Longer Just a Hypothesis? Pharm Res 2022; 39:213-222. [PMID: 35112229 DOI: 10.1007/s11095-022-03172-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/19/2022] [Indexed: 12/14/2022]
Abstract
The Free Drug Hypothesis is a well-established concept within the scientific lexicon pervading many areas of Drug Discovery and Development, and yet it is poorly defined by virtue of many variations appearing in the literature. Clearly, unbound drug is in dynamic equilibrium with respect to absorption, distribution, metabolism, elimination, and indeed, interaction with the desired pharmacological target. Binding interactions be they specific (e.g. high affinity) or nonspecific (e.g. lower affinity/higher capacity) are governed by the same fundamental physicochemical tenets including Hill-Langmuir Isotherms, the Law of Mass Action and Drug Receptor Theory. With this in mind, it is time to recognise a more coherent version and consider it the Free Drug Theory and a hypothesis no longer. Today, we have the experimental and modelling capabilities, pharmacological knowledge, and an improved understanding of unbound drug distribution (e.g. Kpuu) to raise the bar on our understanding and analysis of experimental data. The burden of proof should be to rule out mechanistic possibilities and/or experimental error before jumping to the conclusion that any observations contradict these fundamentals.
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Affiliation(s)
- Scott G Summerfield
- UK Bioanalysis Immunogenicity and Biomarkers, GSK R&D, Stevenage, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK.
| | - James W T Yates
- Drug Metabolism and Pharmacokinetics, GSK R&D, Stevenage, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
| | - David A Fairman
- Clinical Pharmacology Modelling and Simulation, GSK R&D, Stevenage, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
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10
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Jang SM, Awdishu L. Drug dosing considerations in continuous renal replacement therapy. Semin Dial 2021; 34:480-488. [PMID: 33939855 DOI: 10.1111/sdi.12972] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/23/2021] [Accepted: 03/19/2021] [Indexed: 12/24/2022]
Abstract
Acute kidney injury (AKI) is a common complication in critically ill patients, which is associated with increased in-hospital mortality. Delivering effective antibiotics to treat patients with sepsis receiving continuous renal replacement therapy (RRT) is complicated by variability in pharmacokinetics, dialysis delivery, lack of primary literature, and therapeutic drug monitoring. Pharmacokinetic alterations include changes in absorption, distribution, protein binding (PB), metabolism, and renal elimination. Drug absorption may be significantly changed due to alterations in gastric pH, perfusion, gastrointestinal motility, and intestinal atrophy. Volume of distribution for hydrophilic drugs may be increased due to volume overload. Estimation of renal clearance is challenged by the effective delivery of RRT. Drug characteristics such as PB, volume of distribution, and molecular weight impact removal of the drug by RRT. The totality of these alterations leads to reduced exposure. Despite our best knowledge, therapeutic drug monitoring of patients receiving continuous RRT demonstrates wide variability in antimicrobial concentrations, highlighting the need for expanded monitoring of all drugs. This review article will focus on changes in drug pharmacokinetics in AKI and dosing considerations to attain antibiotic pharmacodynamic targets in critically ill patients receiving continuous RRT.
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Affiliation(s)
- Soo Min Jang
- Department of Pharmacy Practice, Loma Linda University School of Pharmacy, Loma Linda, CA, USA
| | - Linda Awdishu
- Clinical Pharmacy, UC San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences, La Jolla, CA, USA
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11
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Neubauer D, Jaśkiewicz M, Bauer M, Olejniczak-Kęder A, Sikorska E, Sikora K, Kamysz W. Biological and Physico-Chemical Characteristics of Arginine-Rich Peptide Gemini Surfactants with Lysine and Cystine Spacers. Int J Mol Sci 2021; 22:3299. [PMID: 33804887 PMCID: PMC8036666 DOI: 10.3390/ijms22073299] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/19/2021] [Accepted: 03/20/2021] [Indexed: 12/11/2022] Open
Abstract
Ultrashort cationic lipopeptides (USCLs) and gemini cationic surfactants are classes of potent antimicrobials. Our recent study has shown that the branching and shortening of the fatty acids chains with the simultaneous addition of a hydrophobic N-terminal amino acid in USCLs result in compounds with enhanced selectivity. Here, this approach was introduced into arginine-rich gemini cationic surfactants. l-cystine diamide and l-lysine amide linkers were used as spacers. Antimicrobial activity against planktonic and biofilm cultures of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) strains and Candida sp. as well as hemolytic and cytotoxic activities were examined. Moreover, antimicrobial activity in the presence of human serum and the ability to form micelles were evaluated. Membrane permeabilization study, serum stability assay, and molecular dynamics were performed. Generally, critical aggregation concentration was linearly correlated with hydrophobicity. Gemini surfactants were more active than the parent USCLs, and they turned out to be selective antimicrobial agents with relatively low hemolytic and cytotoxic activities. Geminis with the l-cystine diamide spacer seem to be less cytotoxic than their l-lysine amide counterparts, but they exhibited lower antibiofilm and antimicrobial activities in serum. In some cases, geminis with branched fatty acid chains and N-terminal hydrophobic amino acid resides exhibited enhanced selectivity to pathogens over human cells.
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Affiliation(s)
- Damian Neubauer
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (M.B.); (K.S.); (W.K.)
| | - Maciej Jaśkiewicz
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (M.B.); (K.S.); (W.K.)
| | - Marta Bauer
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (M.B.); (K.S.); (W.K.)
| | - Agata Olejniczak-Kęder
- Department of Histology, Faculty of Medicine, Medical University of Gdańsk, 80-211 Gdańsk, Poland;
| | - Emilia Sikorska
- Department of Organic Chemistry, Faculty of Chemistry, University of Gdańsk, 80-308 Gdańsk, Poland;
| | - Karol Sikora
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (M.B.); (K.S.); (W.K.)
| | - Wojciech Kamysz
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (M.B.); (K.S.); (W.K.)
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12
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Rayner CR, Smith PF, Andes D, Andrews K, Derendorf H, Friberg LE, Hanna D, Lepak A, Mills E, Polasek TM, Roberts JA, Schuck V, Shelton MJ, Wesche D, Rowland‐Yeo K. Model-Informed Drug Development for Anti-Infectives: State of the Art and Future. Clin Pharmacol Ther 2021; 109:867-891. [PMID: 33555032 PMCID: PMC8014105 DOI: 10.1002/cpt.2198] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/05/2021] [Indexed: 12/13/2022]
Abstract
Model-informed drug development (MIDD) has a long and rich history in infectious diseases. This review describes foundational principles of translational anti-infective pharmacology, including choice of appropriate measures of exposure and pharmacodynamic (PD) measures, patient subpopulations, and drug-drug interactions. Examples are presented for state-of-the-art, empiric, mechanistic, interdisciplinary, and real-world evidence MIDD applications in the development of antibacterials (review of minimum inhibitory concentration-based models, mechanism-based pharmacokinetic/PD (PK/PD) models, PK/PD models of resistance, and immune response), antifungals, antivirals, drugs for the treatment of global health infectious diseases, and medical countermeasures. The degree of adoption of MIDD practices across the infectious diseases field is also summarized. The future application of MIDD in infectious diseases will progress along two planes; "depth" and "breadth" of MIDD methods. "MIDD depth" refers to deeper incorporation of the specific pathogen biology and intrinsic and acquired-resistance mechanisms; host factors, such as immunologic response and infection site, to enable deeper interrogation of pharmacological impact on pathogen clearance; clinical outcome and emergence of resistance from a pathogen; and patient and population perspective. In particular, improved early assessment of the emergence of resistance potential will become a greater focus in MIDD, as this is poorly mitigated by current development approaches. "MIDD breadth" refers to greater adoption of model-centered approaches to anti-infective development. Specifically, this means how various MIDD approaches and translational tools can be integrated or connected in a systematic way that supports decision making by key stakeholders (sponsors, regulators, and payers) across the entire development pathway.
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Affiliation(s)
- Craig R. Rayner
- CertaraPrincetonNew JerseyUSA
- Monash Institute of Pharmaceutical SciencesMonash UniversityMelbourneVictoriaAustralia
| | | | - David Andes
- University of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Kayla Andrews
- Bill & Melinda Gates Medical Research InstituteCambridgeMassachusettsUSA
| | | | | | - Debra Hanna
- Bill & Melinda Gates FoundationSeattleWashingtonUSA
| | - Alex Lepak
- University of Wisconsin‐MadisonMadisonWisconsinUSA
| | | | - Thomas M. Polasek
- CertaraPrincetonNew JerseyUSA
- Centre for Medicines Use and SafetyMonash UniversityMelbourneVictoriaAustralia
- Department of Clinical PharmacologyRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
| | - Jason A. Roberts
- Faculty of MedicineUniversity of Queensland Centre for Clinical ResearchThe University of QueenslandBrisbaneQueenslandAustralia
- Departments of Pharmacy and Intensive Care MedicineRoyal Brisbane and Women’s HospitalBrisbaneQueenslandAustralia
- Division of Anaesthesiology Critical Care Emergency and Pain MedicineNîmes University HospitalUniversity of MontpellierMontpellierFrance
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Jones TW, Jun AH, Michal JL, Olney WJ. High-Dose Daptomycin and Clinical Applications. Ann Pharmacother 2021; 55:1363-1378. [PMID: 33535792 DOI: 10.1177/1060028021991943] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To evaluate evidence for high-dose daptomycin (doses ≥ 8 mg/kg/d). DATA SOURCES A PubMed/MEDLINE literature search was performed (January 2000 to December 2020) using the search terms daptomycin, high dose, and dosing. Review article references and society guidelines were reviewed. STUDY SELECTION AND DATA EXTRACTION Clinical trials, observational studies, retrospective studies, meta-analyses, and systematic reviews reporting on high-dose daptomycin were included. DATA SYNTHESIS Experimentally, daptomycin outperforms other antimicrobials for high inoculum and biofilm-associated infections. Clinically, high-dose daptomycin is supported as salvage and first-line therapy for endocarditis and bacteremia, primarily when caused by methicillin-resistant Staphylococcus aureus (when vancomycin minimum inhibitory concentration is >1 mg/L) and Enterococcus. High-dose daptomycin appears effective for osteomyelitis and central nervous system infections, although comparative studies are lacking. High dosing in renal replacement therapy requires considering clearance modality to achieve exposures like normal renal function. Weight-based dosing in obesity draws concern for elevated exposures, although high doses have not been evaluated kinetically in obesity. Some data show benefits of high doses in overweight populations. Burn patients clear daptomycin more rapidly, and high doses may only achieve drug exposures similar to standard doses (6 mg/kg). RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE This review analyzes the efficacy and safety of high-dose daptomycin in serious gram-positive infections. Discussion of specific infectious etiologies and patient populations should encourage clinicians to evaluate their daptomycin dosing standards. CONCLUSIONS The efficacy of high-dose daptomycin and limited safety concerns encourage clinicians to consider high-dose daptomycin more liberally in severe gram-positive infections.
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14
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Tang WH, Wang CF, Liao YD. Fetal bovine serum albumin inhibits antimicrobial peptide activity and binds drug only in complex with α1-antitrypsin. Sci Rep 2021; 11:1267. [PMID: 33446738 PMCID: PMC7809101 DOI: 10.1038/s41598-020-80540-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/21/2020] [Indexed: 01/30/2023] Open
Abstract
Several antimicrobial peptides (AMPs) have been developed for the treatment of infections caused by antibiotic-resistant microbes, but their applications are primarily limited to topical infections because in circulation they are bound and inhibited by serum proteins. Here we have found that some AMPs, such as TP4 from fish tilapia, and drugs, such as antipyretic ibuprofen, were bound by bovine serum albumin only in complex with α1-antitrypsin which is linked by disulfide bond. They existed in dimeric complex (2 albumin -2 α1-antitrypsin) in the bovine serum only at fetal stage, but not after birth. The hydrophobic residues of TP4 were responsible for its binding to the complex. Since bovine serum is a major supplement in most cell culture media, therefore the existence and depletion of active albumin/α1-antitrypsin complex are very important for the assay and production of biomolecules.
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Affiliation(s)
- Wen-Hung Tang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Chiu-Feng Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - You-Di Liao
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan.
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15
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Hollander A, Yaron S. Pore-forming treatments induce aggregation of Salmonella Senftenberg through protein leakage. Food Microbiol 2020; 96:103721. [PMID: 33494899 DOI: 10.1016/j.fm.2020.103721] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/03/2020] [Accepted: 12/22/2020] [Indexed: 10/22/2022]
Abstract
Fresh herbs are not commonly associated with foodborne pathogens, due to the production of essential oils with antimicrobial activity. Recalls of contaminated basil, and basil outbreaks caused by Salmonella motivated studies aimed to comprehend the antimicrobial activity of basil essential oils, and to explore the mechanisms in which Salmonella can overcome them. Linalool, a major constituent of basil oil, increases the permeability of Salmonella Senftenberg cells by damaging their membrane. Linalool also induces bacterial aggregation. We hypothesized that the membrane perforation effect triggers cell aggregation through leakage of intracellular substances from live and dead cells. By exposing S. Senftenberg to additional physical (sonication) or chemical (eugenol, Triton-X-100) treatments, we showed that the aggregation is caused by various membrane-targeted treatments. Enzymatic degradation of leaked proteins restricted the bacterial aggregation, and disassembled existing aggregates. Moreover, supplemented proteins such as bacterial intracellular proteins or BSA also caused aggregation, further supporting the hypothesis that non-specific proteins trigger the bacterial aggregation. This study provides a novel understanding of the role of protein leakage in promoting bacterial aggregation. Since aggregation has significant roles in food safety and microbial ecology, this finding may establish future studies about microbial resistance via formation of clusters similar to biofilm development.
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Affiliation(s)
- Amit Hollander
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa, Israel
| | - Sima Yaron
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa, Israel.
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16
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Yamasaki K, Sakurama K, Nishi K, Watanabe H, Maruyama T, Seo H, Otagiri M, Taguchi K. Characterization of the Interaction of Daptomycin With Site II on Human Serum Albumin. J Pharm Sci 2020; 109:2919-2924. [PMID: 32565355 DOI: 10.1016/j.xphs.2020.06.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/27/2020] [Accepted: 06/08/2020] [Indexed: 11/16/2022]
Abstract
Daptomycin, a cyclic lipopeptide antibiotic, is clinically used for the treatment of infections caused by Gram-positive bacteria, including the methicillin-resistant Staphylococcus aureus and the vancomycin-resistant Enterococci. While daptomycin shows high plasma protein binding (90-93%), our knowledge of the binding process is not extensive. To address this issue in more detail, we characterized the binding of daptomycin to plasma proteins and the findings indicate that the association constant for the binding of daptomycin to human serum albumin (HSA) is much higher than that for α1-acid glycoprotein, another plasma protein. Daptomycin was also found to bind to a single site on HSA, which was identified as site II. The findings also suggest that the n-decanoyl moiety of daptomycin penetrates into the hydrophobic pocket of site II and that this acyl moiety interacts with Tyr411 at the entrance to site II. Due to this selective interaction with site II, daptomycin binding was significantly inhibited by drugs (ibuprofen or diazepam) and endogenous compounds (uremic toxins or fatty acids) which also strongly bind to site II. In diseased states, such an inhibition in the binding could result in the pharmacokinetics and therapeutic action of daptomycin being substantially altered.
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Affiliation(s)
- Keishi Yamasaki
- Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan; DDS Research Institute, Sojo University, Kumamoto 860-0082, Japan.
| | - Keiki Sakurama
- Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan
| | - Koji Nishi
- Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan
| | - Hiroshi Watanabe
- Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 862-0973, Japan
| | - Toru Maruyama
- Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 862-0973, Japan
| | - Hakaru Seo
- Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan; DDS Research Institute, Sojo University, Kumamoto 860-0082, Japan
| | - Masaki Otagiri
- Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan; DDS Research Institute, Sojo University, Kumamoto 860-0082, Japan
| | - Kazuaki Taguchi
- Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan; Keio University Faculty of Pharmacy, 1-5-30 Shibakoen, Minato-ku, Tokyo, Japan.
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17
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Derendorf H, Heinrichs T, Reimers T, Lebert C, Brinkmann A. Calculated initial parenteral treatment of bacterial infections: Pharmacokinetics and pharmacodynamics. GMS INFECTIOUS DISEASES 2020; 8:Doc17. [PMID: 32373442 PMCID: PMC7186811 DOI: 10.3205/id000061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This is the third chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. The chapter features the pharmacokinetic and pharmacodynamics properties of the most frequently used antiinfective agents.
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Affiliation(s)
- Hartmut Derendorf
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, USA
| | | | - Tobias Reimers
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, USA
| | | | - Alexander Brinkmann
- Klinik für Anästhesie, operative Intensivmedizin und spezielle Schmerztherapie, Klinikum Heidenheim, Germany
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18
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Boudreau MA, Ding D, Meisel JE, Janardhanan J, Spink E, Peng Z, Qian Y, Yamaguchi T, Testero SA, O’Daniel PI, Leemans E, Lastochkin E, Song W, Schroeder VA, Wolter WR, Suckow MA, Mobashery S, Chang M. Structure-Activity Relationship for the Oxadiazole Class of Antibacterials. ACS Med Chem Lett 2020; 11:322-326. [PMID: 32184964 DOI: 10.1021/acsmedchemlett.9b00379] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 10/03/2019] [Indexed: 11/29/2022] Open
Abstract
A structure-activity relationship (SAR) for the oxadiazole class of antibacterials was evaluated by syntheses of 72 analogs and determination of the minimal-inhibitory concentrations (MICs) against the ESKAPE panel of bacteria. Selected compounds were further evaluated for in vitro toxicity, plasma protein binding, pharmacokinetics (PK), and a mouse model of methicillin-resistant Staphylococcus aureus (MRSA) infection. Oxadiazole 72c shows potent in vitro antibacterial activity, exhibits low clearance, a high volume of distribution, and 41% oral bioavailability, and shows efficacy in mouse models of MRSA infection.
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Affiliation(s)
- Marc A. Boudreau
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Derong Ding
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jayda E. Meisel
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jeshina Janardhanan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Edward Spink
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Zhihong Peng
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Yuanyuan Qian
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Takao Yamaguchi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Sebastian A. Testero
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Peter I. O’Daniel
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Erika Leemans
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Elena Lastochkin
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Wei Song
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Valerie A. Schroeder
- Freimann Life Sciences Center and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William R. Wolter
- Freimann Life Sciences Center and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Mark A. Suckow
- Freimann Life Sciences Center and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Mayland Chang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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19
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Zhang X, Han D, Pei P, Hao J, Lu Y, Wan P, Peng X, Lv W, Xiong W, Zeng Z. In vitro Antibacterial Activity of Isopropoxy Benzene Guanidine Against Multidrug-Resistant Enterococci. Infect Drug Resist 2019; 12:3943-3953. [PMID: 31920348 PMCID: PMC6934121 DOI: 10.2147/idr.s234509] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Accepted: 11/22/2019] [Indexed: 12/23/2022] Open
Abstract
Background Bacterial infections cause a serious public health crisis due to the emergence of resistance towards multiple conventional antibacterial drugs. In particular, multidrug-resistant (MDR) Enterococcus faecium which belongs to "ESKAPE" organisms is causing significant problems worldwide. Hence, there is an urgent need to find alternative therapies. Recently, substituted benzene guanidine compounds have been used as lead structures to discover new promising drugs in both synthetic and medicinal chemistry. Purpose Here we investigated the antimicrobial activity of a new substituted benzene guanidine analog, isopropoxy benzene guanidine, against Enterococci. Material and methods The isopropoxy benzene guanidine was synthesized by Guangzhou Insighter Biotechnology Co., Ltd and tested on both reference bacterial strain and 32 clinical MDR Enterococci strains. The in vitro antibacterial activity was evaluated by microdilution method and kill kinetic assays. The potential antibacterial mechanism was measured by fluorescence spectrometry using fluorescent membrane potential probe 3, 3-diethyloxacarbocyanine iodide (DiOC2 (3)). Results Isopropoxy benzene guanidine exhibited potent bactericidal activity against both reference strain and MDR Enterococci isolates. The minimum inhibitory concentration (MIC) range for isopropoxy benzene guanidine was 1-4 μg/mL. Minimum bactericidal concentration (MBC) was about 2-8-fold of its MIC values. Time-kill studies showed that isopropoxy benzene guanidine provided superior bactericidal effect against reference and MDR strains within 12 hrs at 2×MIC. Furthermore, isopropoxy benzene guanidine could cause a large reduction in the magnitude of the generated membrane potential compared to that of the untreated cells. Conclusion The present study highlights the potent bactericidal activity of isopropoxy benzene guanidine on Enterococci by disrupting the cell membrane potential. These findings demonstrate that isopropoxy benzene guanidine may be a good chemical lead for further medicinal chemistry and pharmaceutical development and could be used as a therapeutic agent for infectious diseases caused by MDR Enterococci.
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Affiliation(s)
- Xiufeng Zhang
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Dongdong Han
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Pengfei Pei
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Jie Hao
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Yixing Lu
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Peng Wan
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Xianfeng Peng
- Guangzhou Insighter Biotechnology Co., Ltd, Guangzhou 510642, People's Republic of China
| | - Weibiao Lv
- Department of Clinical Laboratory, Shunde Hospital, Southern Medical University (The First People's Hospital of Shunde), Foshan 528000, People's Republic of China
| | - Wenguang Xiong
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Zhenling Zeng
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou 510642, People's Republic of China.,Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou 510642, People's Republic of China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, People's Republic of China
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20
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Cai Y, Zhong Z, He C, Xia H, Hu Q, Wang Y, Ye Q, Zhou J. Homogeneously Synthesized Hydroxybutyl Chitosans in Alkali/Urea Aqueous Solutions as Potential Wound Dressings. ACS APPLIED BIO MATERIALS 2019; 2:4291-4302. [DOI: 10.1021/acsabm.9b00553] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Yan Cai
- Department of Chemistry, Hubei Engineering Center of Natural Polymers-based Medical Materials, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Zibiao Zhong
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Chen He
- Department of Chemistry, Hubei Engineering Center of Natural Polymers-based Medical Materials, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Haoyang Xia
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Qianchao Hu
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Yanfeng Wang
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Qifa Ye
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Jinping Zhou
- Department of Chemistry, Hubei Engineering Center of Natural Polymers-based Medical Materials, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University, Wuhan 430072, China
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21
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Cai Y, Cao J, Xu C, Zhou J. Thermo-responsive behaviors and bioactivities of hydroxybutyl chitosans prepared in alkali/urea aqueous solutions. Carbohydr Polym 2019; 215:90-98. [DOI: 10.1016/j.carbpol.2019.03.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/07/2019] [Accepted: 03/13/2019] [Indexed: 12/29/2022]
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Effects of Microplate Type and Broth Additives on Microdilution MIC Susceptibility Assays. Antimicrob Agents Chemother 2018; 63:AAC.01760-18. [PMID: 30397070 PMCID: PMC6325200 DOI: 10.1128/aac.01760-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/27/2018] [Indexed: 11/20/2022] Open
Abstract
The determination of antibiotic potency against bacterial strains by assessment of their minimum inhibitory concentration normally uses a standardized broth microdilution assay procedure developed more than 50 years ago. However, certain antibiotics require modified assay conditions in order to observe optimal activity. The determination of antibiotic potency against bacterial strains by assessment of their minimum inhibitory concentration normally uses a standardized broth microdilution assay procedure developed more than 50 years ago. However, certain antibiotics require modified assay conditions in order to observe optimal activity. For example, daptomycin requires medium supplemented with Ca2+, and the lipoglycopeptides dalbavancin and oritavancin require Tween 80 to be added to the growth medium to prevent the depletion of free drug via adsorption to the plastic microplate. In this report, we examine systematically the effects of several different plate types on microdilution broth MIC values for a set of antibiotics against Gram-positive and Gram-negative bacteria, both in medium alone and in medium supplemented with the commonly used additives Tween 80, lysed horse blood, and 50% human serum. We observed very significant differences in measured MICs (up to 100-fold) for some lipophilic antibiotics, such as the Gram-positive lipoglycopeptide dalbavancin and the Gram-negative lipopeptide polymyxins, and found that nonspecific binding plates can replace the need for surfactant additives. Microtiter plate types and any additives should be specified when reporting broth dilution MIC values, as results can vary dramatically for some classes of antibiotics.
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Tanaka R, Suzuki Y, Goto K, Yasuda N, Koga H, Kai S, Ohchi Y, Sato Y, Kitano T, Itoh H. Development and validation of sensitive and selective quantification of total and free daptomycin in human plasma using ultra-performance liquid chromatography coupled to tandem mass spectrometry. J Pharm Biomed Anal 2018; 165:56-64. [PMID: 30502552 DOI: 10.1016/j.jpba.2018.11.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 11/16/2018] [Accepted: 11/19/2018] [Indexed: 12/15/2022]
Abstract
Recently, several studies on pharmacokinetics parameters of daptomycin reported that plasma trough concentration was linked to efficacy and adverse effects, suggesting the usefulness of therapeutic drug monitoring. Although some methods for determining total daptomycin concentration using liquid chromatography coupled to tandem mass spectrometry were established previously, no sensitive quantification method for free drug concentration was established. In this study, we aimed to develop a quantitative method of measuring both total and free daptomycin concentrations using ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS), by which both trough and maximum concentrations can be measured. Plasma samples were prepared by solid phase extraction. Free fractions were obtained by ultrafiltration. The assay fulfilled the requirements of US Food and Drug Administration and the European Medicines Agency for assay validation. The methods for total and free drug showed good fit over wide ranges of 0.5-200 and 0.04-40 μg/mL, with lower limits of quantitation of 0.5 and 0.04 μg/mL, respectively. Recovery rate of free daptomycin from ultrafiltration was approximately 100%. Extraction recovery rates of total and free drug measurements ranged from 57.1 to 67.4% and 54.6 to 62.3%, while matrix effect varied between 111.9 and 118.7% and 104.0 and 127.1%, respectively. The maximum and trough concentrations of total and free daptomycin in plasma from two patients in intensive care unit were successfully determined, demonstrating the feasibility of clinical application of the novel methods for determining plasma total and free daptomycin concentrations. In conclusion, we succeeded to develop a sensitive and selective method using UPLC-MS/MS for quantitative measurement of total and free daptomycin concentrations in plasma.
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Affiliation(s)
- Ryota Tanaka
- Department of Clinical Pharmacy, Oita University Hospital, Yufu-shi, Oita, Japan.
| | - Yosuke Suzuki
- Department of Clinical Pharmacy, Oita University Hospital, Yufu-shi, Oita, Japan
| | - Koji Goto
- Department of Anesthesiology and Intensive Care, Faculty of Medicine, Oita University, Yufu-shi, Oita, Japan
| | - Norihisa Yasuda
- Department of Anesthesiology and Intensive Care, Faculty of Medicine, Oita University, Yufu-shi, Oita, Japan
| | - Hironori Koga
- Department of Anesthesiology and Intensive Care, Faculty of Medicine, Oita University, Yufu-shi, Oita, Japan
| | - Shinya Kai
- Department of Anesthesiology and Intensive Care, Faculty of Medicine, Oita University, Yufu-shi, Oita, Japan
| | - Yoshifumi Ohchi
- Department of Anesthesiology and Intensive Care, Faculty of Medicine, Oita University, Yufu-shi, Oita, Japan
| | - Yuhki Sato
- Department of Clinical Pharmacy, Oita University Hospital, Yufu-shi, Oita, Japan
| | - Takaaki Kitano
- Department of Anesthesiology and Intensive Care, Faculty of Medicine, Oita University, Yufu-shi, Oita, Japan
| | - Hiroki Itoh
- Department of Clinical Pharmacy, Oita University Hospital, Yufu-shi, Oita, Japan
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Adiraju SKS, Shekar K, Fraser JF, Smith MT, Ghassabian S. Effect of cardiopulmonary bypass on cytochrome P450 enzyme activity: implications for pharmacotherapy. Drug Metab Rev 2017; 50:109-124. [PMID: 29254370 DOI: 10.1080/03602532.2017.1417423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
For patients undergoing cardiopulmonary bypass (CPB) during cardiac surgery, there are well-documented changes in the pharmacokinetics (PK) of commonly administered drugs. Although multiple factors potentially underpin these changes, there has been scant research attention on the impact of CPB to alter the activities of cytochrome P450 (CYP) isoenzymes. PK changes during cardiac surgery with CPB have the potential to adversely affect the safety and efficacy of pharmacotherapy and increase the risk of drug-drug interactions. Clinically significant changes in drug PK during CPB are likely to be prominent for drugs where CYP metabolism is a major clearance (CL) mechanism. However, clinical data from patients undergoing CPB surgery in support of this hypothesis are lacking, leaving a significant knowledge gap. In this review, we address the effects of CPB on the release of pro-inflammatory cytokines, in surgeries with and without CPB, both pre and post initiation of surgery. We reviewed literature to explore the relationship between the release of pro-inflammatory cytokines, and the expression and activities of CYP enzymes. Through this approach, we provide new insight on the effects of CPB on the PK of drugs administered to patients in the clinical setting. Future research to address this knowledge gap will have considerable impact to assist clinicians with optimizing pharmacotherapy in this patient population.
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Affiliation(s)
- Santosh Kumar Sreevatsav Adiraju
- a Centre for Integrated Preclinical Drug Development, Centre for Clinical Research, Faculty of Medicine , The University of Queensland , Brisbane , QLD , Australia
| | - Kiran Shekar
- b Critical Care Research Group , The Prince Charles Hospital and The University of Queensland , Brisbane , QLD , Australia
| | - John F Fraser
- b Critical Care Research Group , The Prince Charles Hospital and The University of Queensland , Brisbane , QLD , Australia
| | - Maree T Smith
- a Centre for Integrated Preclinical Drug Development, Centre for Clinical Research, Faculty of Medicine , The University of Queensland , Brisbane , QLD , Australia.,c School of Pharmacy, Faculty of Health and Behavioral Sciences , The University of Queensland , Brisbane , QLD , Australia
| | - Sussan Ghassabian
- a Centre for Integrated Preclinical Drug Development, Centre for Clinical Research, Faculty of Medicine , The University of Queensland , Brisbane , QLD , Australia
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25
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Evaluation of robenidine analog NCL195 as a novel broad-spectrum antibacterial agent. PLoS One 2017; 12:e0183457. [PMID: 28873428 PMCID: PMC5584945 DOI: 10.1371/journal.pone.0183457] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 08/06/2017] [Indexed: 01/15/2023] Open
Abstract
The spread of multidrug resistance among bacterial pathogens poses a serious threat to public health worldwide. Recent approaches towards combating antimicrobial resistance include repurposing old compounds with known safety and development pathways as new antibacterial classes with novel mechanisms of action. Here we show that an analog of the anticoccidial drug robenidine (4,6-bis(2-((E)-4-methylbenzylidene)hydrazinyl)pyrimidin-2-amine; NCL195) displays potent bactericidal activity against Streptococcus pneumoniae and Staphylococcus aureus by disrupting the cell membrane potential. NCL195 was less cytotoxic to mammalian cell lines than the parent compound, showed low metabolic degradation rates by human and mouse liver microsomes, and exhibited high plasma concentration and low plasma clearance rates in mice. NCL195 was bactericidal against Acinetobacter spp and Neisseria meningitidis and also demonstrated potent activity against A. baumannii, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae and Enterobacter spp. in the presence of sub-inhibitory concentrations of ethylenediaminetetraacetic acid (EDTA) and polymyxin B. These findings demonstrate that NCL195 represents a new chemical lead for further medicinal chemistry and pharmaceutical development to enhance potency, solubility and selectivity against serious bacterial pathogens.
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26
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Bacteriological profiling of diphenylureas as a novel class of antibiotics against methicillin-resistant Staphylococcus aureus. PLoS One 2017; 12:e0182821. [PMID: 28797064 PMCID: PMC5552351 DOI: 10.1371/journal.pone.0182821] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 07/25/2017] [Indexed: 11/18/2022] Open
Abstract
Bacterial resistance to antibiotics remains an imposing global public health challenge. Of the most serious pathogens, methicillin-resistant Staphylococcus aureus (MRSA) is problematic given strains have emerged that exhibit resistance to several antibiotic classes including β-lactams and agents of last resort such as vancomycin. New antibacterial agents composed of unique chemical scaffolds are needed to counter this public health challenge. The present study examines two synthetic diphenylurea compounds 1 and 2 that inhibit growth of clinically-relevant isolates of MRSA at concentrations as low as 4 µg/mL and are non-toxic to human colorectal cells at concentrations up to 128 μg/mL. Both compounds exhibit rapid bactericidal activity, completely eliminating a high inoculum of MRSA within four hours. MRSA mutants exhibiting resistance to 1 and 2 could not be isolated, indicating a low likelihood of rapid resistance emerging to these compounds. Bacterial cytological profiling revealed the diphenylureas exert their antibacterial activity by targeting bacterial cell wall synthesis. Both compounds demonstrate the ability to resensitize vancomycin-resistant Staphylococcus aureus to the effect of vancomycin. The present study lays the foundation for further investigation and development of diphenylurea compounds as a new class of antibacterial agents.
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27
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Li J, Xie S, Ahmed S, Wang F, Gu Y, Zhang C, Chai X, Wu Y, Cai J, Cheng G. Antimicrobial Activity and Resistance: Influencing Factors. Front Pharmacol 2017; 8:364. [PMID: 28659799 PMCID: PMC5468421 DOI: 10.3389/fphar.2017.00364] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 05/26/2017] [Indexed: 01/09/2023] Open
Abstract
Rational use of antibiotic is the key approach to improve the antibiotic performance and tackling of the antimicrobial resistance. The efficacy of antimicrobials are influenced by many factors: (1) bacterial status (susceptibility and resistance, tolerance, persistence, biofilm) and inoculum size; (2) antimicrobial concentrations [mutant selection window (MSW) and sub-inhibitory concentration]; (3) host factors (serum effect and impact on gut micro-biota). Additional understandings regarding the linkage between antimicrobial usages, bacterial status and host response offers us new insights and encourage the struggle for the designing of antimicrobial treatment regimens that reaching better clinical outcome and minimizing the emergence of resistance at the same time.
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Affiliation(s)
- Jun Li
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for The Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
| | - Shuyu Xie
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for The Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
| | - Saeed Ahmed
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for The Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
| | - Funan Wang
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for The Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
| | - Yufeng Gu
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for The Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
| | - Chaonan Zhang
- Basic Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Ximan Chai
- Basic Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Yalan Wu
- Basic Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Jinxia Cai
- Basic Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
| | - Guyue Cheng
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for The Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China.,Basic Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China
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28
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Schneider EK, Huang JX, Carbone V, Han M, Zhu Y, Nang S, Khoo KK, Mak J, Cooper MA, Li J, Velkov T. Plasma Protein Binding Structure-Activity Relationships Related to the N-Terminus of Daptomycin. ACS Infect Dis 2017; 3:249-258. [PMID: 28142234 DOI: 10.1021/acsinfecdis.7b00015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Daptomycin is a lipopeptide antibiotic that is highly bound to plasma proteins. To date, the plasma components and structure-activity relationships responsible for the plasma protein binding profile of daptomycin remain uncharacterized. In the present study we have employed a surface plasmon resonance assay together with molecular docking techniques to investigate the plasma protein binding structure-activity relationships related to the N-terminal fatty acyl of daptomycin. Three compounds were investigated: (1) native daptomycin, which displays an N-terminal n-decanoyl fatty acid side chain, and two analogues with modifications to the N-terminal fatty acyl chain; (2) des-acyl daptomycin; and (3) acetyl-daptomycin. The surface plasmon resonance (SPR) data showed that the binding profile of native daptomycin was in the rank order human serum albumin (HSA) ≫ α-1-antitrypsin > low-density lipoprotein ≥ hemoglobin > sex hormone binding globulin > α-1-acid-glycoprotein (AGP) > hemopexin > fibrinogen > α-2-macroglobulin > β2-microglobulin > high-density lipoprotein > fibronectin > haptoglobulin > transferrin > immunoglobulin G. Notably, binding to fatty acid free HSA was greater than binding to nondelipidated HSA. SPR and ultrafiltration studies also indicated that physiological concentrations of calcium increase binding of daptomycin and acetyl-daptomycin to HSA and AGP. A molecular model of the daptomycin-human serum albumin A complex is presented that illustrates the pivotal role of the N-terminal fatty acyl chain of daptomycin for binding to drug site 1 of HSA. In proof-of-concept, the capacity of physiological cocktails of the identified plasma proteins to inhibit the antibacterial activity of daptomycin was assessed with in vitro microbiological assays. We show that HSA, α-1-antitrypsin, low-density lipoprotein, sex hormone binding globulin, α-1-acid-glycoprotein, and hemopexin are responsible for the majority of the sequestering activity in human plasma. The findings are relevant to medicinal chemistry programs focused on the development of next-generation daptomycin lipopeptides. Tailored modifications to the N-terminal fatty acyl domain of the daptomycin molecule should yield novel daptomycin lipopeptides with more ideal plasma protein binding profiles to increase the levels of active (free) drug in plasma and improved in vivo activity.
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Affiliation(s)
- Elena K. Schneider
- Drug Development
and Innovation, Drug Delivery, Disposition and Dynamics. Monash Institute
of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Johnny X. Huang
- Institute for Molecular
Bioscience, The University of Queensland 306 Carmody Road St. Lucia QLD 4072, Australia
| | - Vincenzo Carbone
- Animal Nutrition and Health, Grasslands
Research Centre, Ag Research Limited, Tennent Drive,
Private Bag 11008, Palmerston North 4442, New Zealand
| | - Meiling Han
- Drug Development
and Innovation, Drug Delivery, Disposition and Dynamics. Monash Institute
of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Yan Zhu
- Monash Biomedicine Discovery Institute,
Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
| | - Sue Nang
- Monash Biomedicine Discovery Institute,
Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
| | - Keith K. Khoo
- School
of Medicine, Deakin University, Geelong, VIC 3216, Australia
| | - Johnson Mak
- School
of Medicine, Deakin University, Geelong, VIC 3216, Australia
| | - Matthew A. Cooper
- Institute for Molecular
Bioscience, The University of Queensland 306 Carmody Road St. Lucia QLD 4072, Australia
| | - Jian Li
- Monash Biomedicine Discovery Institute,
Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
| | - Tony Velkov
- Drug Development
and Innovation, Drug Delivery, Disposition and Dynamics. Monash Institute
of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
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29
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El-Najjar N, Jantsch J, Gessner A. The use of liquid chromatography-tandem mass spectrometry for therapeutic drug monitoring of antibiotics in cancer patients. ACTA ACUST UNITED AC 2017; 55:1246-1261. [DOI: 10.1515/cclm-2016-0700] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 11/28/2016] [Indexed: 12/24/2022]
Abstract
AbstractCancer remains a leading cause of mortality and morbidity worldwide. In addition to organ failure, the most frequent reasons for admission of cancer patients to intensive care units (ICU) are: infections and sepsis. As critically ill, the complexity of the health situation of cancer patients renders the standard antimicrobial regimen more complex and even inadequate which results in increased mortality rates. This is due to pathophysiological changes in the volume of distribution, increased clearance, as well as to organ dysfunction. While in the former cases a decrease in drug efficacy is observed, the hallmark of the latter one is overdosing leading to increased toxicity at the expense of efficacy. Furthermore, an additional risk factor is the potential drug-drug interaction between antibiotics and antineoplastic agents. Therefore, therapeutic drug monitoring (TDM) is a necessity to improve the clinical outcome of antimicrobial therapy in cancer patients. To be applied in routine analysis the method used for TDM should be cheap, fast and highly accurate/sensitive. Furthermore, as ICU patients are treated with a cocktail of antibiotics the method has to cover the simultaneous analysis of antibiotics used as a first/second line of treatment. The aim of the current review is to briefly survey the pitfalls in the current antimicrobial therapy and the central role of TDM in dose adjustment and drug-drug interaction’s evaluation. A major section is dedicated to summarize the currently published analytical methods and to shed light on the difficulties and potential problems that can be encountered during method development.
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30
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Clinical Pharmacology Studies in Critically Ill Children. Pharm Res 2016; 34:7-24. [PMID: 27585904 DOI: 10.1007/s11095-016-2033-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 08/25/2016] [Indexed: 12/19/2022]
Abstract
Developmental and physiological changes in children contribute to variation in drug disposition with age. Additionally, critically ill children suffer from various life-threatening conditions that can lead to pathophysiological alterations that further affect pharmacokinetics (PK). Some factors that can alter PK in this patient population include variability in tissue distribution caused by protein binding changes and fluid shifts, altered drug elimination due to organ dysfunction, and use of medical interventions that can affect drug disposition (e.g., extracorporeal membrane oxygenation and continuous renal replacement therapy). Performing clinical studies in critically ill children is challenging because there is large inter-subject variability in the severity and time course of organ dysfunction; some critical illnesses are rare, which can affect subject enrollment; and critically ill children usually have multiple organ failure, necessitating careful selection of a study design. As a result, drug dosing in critically ill children is often based on extrapolations from adults or non-critically ill children. Dedicated clinical studies in critically ill children are urgently needed to identify optimal dosing of drugs in this vulnerable population. This review will summarize the effect of critical illness on pediatric PK, the challenges associated with performing studies in this vulnerable subpopulation, and the clinical PK studies performed to date for commonly used drugs.
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31
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Abushahba MF, Mohammad H, Seleem MN. Targeting Multidrug-resistant Staphylococci with an anti-rpoA Peptide Nucleic Acid Conjugated to the HIV-1 TAT Cell Penetrating Peptide. MOLECULAR THERAPY-NUCLEIC ACIDS 2016; 5:e339. [PMID: 27434684 PMCID: PMC5330942 DOI: 10.1038/mtna.2016.53] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 06/13/2016] [Indexed: 01/22/2023]
Abstract
Staphylococcus aureus infections present a serious challenge to healthcare practitioners due to the emergence of resistance to numerous conventional antibiotics. Due to their unique mode of action, peptide nucleic acids are novel alternatives to traditional antibiotics to tackle the issue of bacterial multidrug resistance. In this study, we designed a peptide nucleic acid covalently conjugated to the HIV-TAT cell penetrating peptide (GRKKKRRQRRRYK) in order to target the RNA polymerase α subunit gene (rpoA) required for bacterial genes transcription. We explored the antimicrobial activity of the anti-rpoA construct (peptide nucleic acid-TAT) against methicillin-resistant S. aureus, vancomycin-intermediate S. aureus, vancomycin-resistant S. aureus, linezolid-resistant S. aureus, and methicillin-resistant S. epidermidis in pure culture, infected mammalian cell culture, and in an in vivo Caenorhabditis elegans infection model. The anti-rpoA construct led to a concentration-dependent inhibition of bacterial growth (at micromolar concentrations) in vitro and in both infected cell culture and in vivo in C. elegans. Moreover, rpoA gene silencing resulted in suppression of its message as well as reduced expression of two important methicillin-resistant S. aureus USA300 toxins (α-hemolysin and Panton-Valentine leukocidin). This study confirms that rpoA gene is a potential target for development of novel antisense therapeutics to treat infections caused by methicillin-resistant S. aureus.
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Affiliation(s)
- Mostafa Fn Abushahba
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, USA
| | - Haroon Mohammad
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, USA
| | - Mohamed N Seleem
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, USA.,Purdue Institute for Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana, USA
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32
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Parker SL, Dorofaeff T, Lipman J, Ballot DE, Bandini RM, Wallis SC, Roberts JA. Is there a role for microsampling in antibiotic pharmacokinetic studies? Expert Opin Drug Metab Toxicol 2016; 12:601-14. [PMID: 27087416 DOI: 10.1080/17425255.2016.1178238] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Clinical pharmacokinetic studies of antibiotics can establish evidence-based dosing regimens that improve the likelihood of eradicating the pathogen at the site of infection, reduce the potential for selection of resistant pathogens, and minimize harm to the patient. Innovations in small volume sampling (< 50 μL) or 'microsampling' may result in less-invasive sample collection, self-sampling and dried storage. Microsampling may open up opportunities in patient groups where sampling is challenging. AREAS COVERED The challenges for implementation of microsampling to assure suitability of the results, include: acceptable study design, regulatory agency acceptance, and meeting bioanalytical validation requirements. This manuscript covers various microsampling methods, including dried blood/plasma spots, volumetric absorptive microsampling, capillary microsampling, plasma preparation technologies and solid-phase microextraction. EXPERT OPINION The available analytical technology is being underutilized due to a lack of bridging studies and validated bioanalytical methods. These deficiencies represent major impediments to the application of microsampling to antibiotic pharmacokinetic studies. A conceptual framework for the assessment of the suitability of microsampling in clinical pharmacokinetic studies of antibiotics is provided. This model establishes a 'contingency approach' with consideration of the antibiotic and the type and location of the patient, as well as the more prescriptive bioanalytical validation protocols.
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Affiliation(s)
- Suzanne L Parker
- a Burns, Trauma and Critical Care Research Centre , The University of Queensland , Brisbane , Australia
| | - Tavey Dorofaeff
- a Burns, Trauma and Critical Care Research Centre , The University of Queensland , Brisbane , Australia.,b Paediatric Intensive Care , Lady Cilento Children's Hospital , Brisbane , Australia
| | - Jeffrey Lipman
- a Burns, Trauma and Critical Care Research Centre , The University of Queensland , Brisbane , Australia.,c Department of Intensive Care Medicine , Royal Brisbane and Women's Hospital , Brisbane , Australia.,d Faculty of Health , Queensland University of Technology , Brisbane , Australia
| | - Daynia E Ballot
- e Department of Paediatrics and Child Health , University of the Witwatersrand , Johannesburg , South Africa.,f Wits UQ Critical Care Infection Collaboration , Johannesburg , South Africa
| | - Rossella M Bandini
- g School of Physiology , University of the Witwatersrand , Johannesburg , South Africa
| | - Steven C Wallis
- a Burns, Trauma and Critical Care Research Centre , The University of Queensland , Brisbane , Australia
| | - Jason A Roberts
- a Burns, Trauma and Critical Care Research Centre , The University of Queensland , Brisbane , Australia.,c Department of Intensive Care Medicine , Royal Brisbane and Women's Hospital , Brisbane , Australia.,h Department of Pharmacy , Royal Brisbane and Women's Hospital , Brisbane , Australia.,i School of Pharmacy , The University of Queensland , Brisbane , Australia
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33
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Abraham RJ, Stevens AJ, Young KA, Russell C, Qvist A, Khazandi M, Wong HS, Abraham S, Ogunniyi AD, Page SW, O'Handley R, McCluskey A, Trott DJ. Robenidine Analogues as Gram-Positive Antibacterial Agents. J Med Chem 2016; 59:2126-38. [PMID: 26765953 DOI: 10.1021/acs.jmedchem.5b01797] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Robenidine, 1 (2,2'-bis[(4-chlorophenyl)methylene]carbonimidic dihydrazide), was active against MRSA and VRE with MIC's of 8.1 and 4.7 μM, respectively. SAR revealed tolerance for 4-Cl isosteres with 4-F (8), 3-F (9), 3-CH3 (22), and 4-C(CH3)3 (27) (23.7-71 μM) and with 3-Cl (3), 4-CH3 (21), and 4-CH(CH3)2 (26) (8.1-13.0 μM). Imine carbon alkylation identified a methyl/ethyl binding pocket that also accommodated a CH2OH moiety (75; 2,2'-bis[1-(4-chlorophenyl)-2-hydroxyethylidene]carbonimidic dihydrazide). Analogues 1, 27 (2,2'-bis{[4-(1,1-dimethylethyl)phenyl]methylene}carbonimidic dihydrazide), and 69 (2,2'-bis[1-(4-chlorophenyl)ethylidene]carbonimidic dihydrazide hydrochloride) were active against 24 clinical MRSA and MSSA isolates. No dose-limiting cytotoxicity at ≥2× MIC or hemolysis at ≥8× MIC was observed. Polymyxin B addition engendered Escherichia coli and Pseudomonas aeruginosa Gram-negative activity MIC's of 4.2-21.6 μM. 1 and 75 displayed excellent microsomal stability, intrinsic clearance, and hepatic extraction ratios with T1/2 > 247 min, CLint < 7 μL/min/mg protein, and EH < 0.22 in both human and mouse liposomes for 1 and in human liposomes for 75.
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Affiliation(s)
- Rebecca J Abraham
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia
| | - Andrew J Stevens
- Chemistry, Centre for Chemical Biology, School of Environmental and Life Sciences, The University of Newcastle , University Drive, Callaghan, 2308 NSW, Australia
| | - Kelly A Young
- Chemistry, Centre for Chemical Biology, School of Environmental and Life Sciences, The University of Newcastle , University Drive, Callaghan, 2308 NSW, Australia
| | - Cecilia Russell
- Chemistry, Centre for Chemical Biology, School of Environmental and Life Sciences, The University of Newcastle , University Drive, Callaghan, 2308 NSW, Australia
| | - Anastasia Qvist
- Chemistry, Centre for Chemical Biology, School of Environmental and Life Sciences, The University of Newcastle , University Drive, Callaghan, 2308 NSW, Australia
| | - Manouchehr Khazandi
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia
| | - Hui San Wong
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia
| | - Sam Abraham
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia.,School of Veterinary and Life Sciences, Murdoch University , 90 South Street, Murdoch, 6150 WA, Australia
| | - Abiodun D Ogunniyi
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia
| | | | - Ryan O'Handley
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia
| | - Adam McCluskey
- Chemistry, Centre for Chemical Biology, School of Environmental and Life Sciences, The University of Newcastle , University Drive, Callaghan, 2308 NSW, Australia
| | - Darren J Trott
- School of Animal and Veterinary Sciences, University of Adelaide , Roseworthy Campus, Mudla Wirra Road, Roseworthy, 5371 SA, Australia
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34
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Senneville E, Caillon J, Calvet B, Jehl F. Towards a definition of daptomycin optimal dose: Lessons learned from experimental and clinical data. Int J Antimicrob Agents 2015; 47:12-9. [PMID: 26712134 DOI: 10.1016/j.ijantimicag.2015.11.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 11/04/2015] [Accepted: 11/06/2015] [Indexed: 01/25/2023]
Abstract
Daptomycin exhibits excellent antibacterial activity against a wide range of Gram-positive bacteria. The on-label standard daily doses for daptomycin are 4 mg/kg for skin infections and 6 mg/kg for bacteraemia or right-sided endocarditis. Daptomycin bactericidal activity is predominantly concentration-dependent and by considering the values of pharmacokinetic targets established by several authors as well as the peak and trough concentrations of daptomycin obtained at various daily dosages, it appears that these targets can easily be reached with a dose of 6 mg/kg but only for a minimum inhibitory concentration (MIC) at 0.1 mg/L, and that for increasing MICs (e.g. 0.5 mg/L or 1 mg/L) these targets may only be attained with higher dosages (i.e. ≥10 mg/kg). High-dose (HD) daptomycin therapy has also been proven to be effective for reducing the risk of selection of daptomycin-resistant strains. Given the concentration-dependent bactericidal activity of daptomycin, the absence of a dose-toxicity relationship and the need to prevent the selection of resistant strains, we propose to consider for staphylococcal (i) skin and soft-tissue infections, daily doses of daptomycin of 6 mg/kg (new standard dose) and (ii) endocarditis or bacteraemia including those associated with intravascular catheter and implant-related infections, ≥10 mg/kg (HD) when the MIC is unknown or >0.25 mg/L, and 6-10 mg/kg (intermediate doses) when the MIC is ≤0.25 mg/L. For severe and deep-seated enterococcal infections, we propose high (≥10 mg/kg) daily doses of daptomycin in combination with another active agent, especially a β-lactam.
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Affiliation(s)
- Eric Senneville
- Infectious Diseases Department, Gustave Dron Hospital, University of Lille II, Tourcoing, France.
| | - Jocelyne Caillon
- Laboratory of Bacteriology, University of Nantes, Nantes, France
| | - Brigitte Calvet
- Department of Anesthesiology, General Hospital of Béziers, Béziers, France
| | - François Jehl
- Laboratory of Bacteriology, University of Strasbourg, Strasbourg, France
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35
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Tsai D, Jamal JA, Davis JS, Lipman J, Roberts JA. Interethnic differences in pharmacokinetics of antibacterials. Clin Pharmacokinet 2015; 54:243-60. [PMID: 25385446 DOI: 10.1007/s40262-014-0209-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Optimal antibacterial dosing is imperative for maximising clinical outcome. Many factors can contribute to changes in the pharmacokinetics of antibacterials to the extent where dose adjustment may be needed. In acute illness, substantial changes in important pharmacokinetic parameters such as volume of distribution and clearance can occur for certain antibacterials. The possibility of interethnic pharmacokinetic differences can further complicate attempts to design an appropriate dosing regimen. Factors of ethnicity, such as genetics, body size and fat distribution, contribute to differences in absorption, distribution, metabolism and elimination of drugs. Despite extensive previous work on the altered pharmacokinetics of antibacterials in some patient groups such as the critically ill, knowledge of interethnic pharmacokinetic differences for antibacterials is limited. OBJECTIVES This systematic review aims to describe any pharmacokinetic differences in antibacterials between different ethnic groups, and discuss their probable mechanisms as well as any clinical implications. METHODS We performed a structured literature review to identify and describe available data of the interethnic differences in the pharmacokinetics of antibacterials. RESULTS We found 50 articles that met our inclusion criteria and only six of these compared antibacterial pharmacokinetics between different ethnicities within the same study. Overall, there was limited evidence available. We found that interethnic pharmacokinetic differences are negligible for carbapenems, most β-lactams, aminoglycosides, glycopeptides, most fluoroquinolones, linezolid and daptomycin, whereas significant difference is likely for ciprofloxacin, macrolides, clindamycin, tinidazole and some cephalosporins. In general, subjects of Asian ethnicity achieve drug exposures up to two to threefold greater than Caucasian counterparts for these antibacterials. This difference is caused by a comparatively lower volume of distribution and/or drug clearance. CONCLUSION Interethnic pharmacokinetic differences of antibacterials are likely; however, the clinical relevance of these differences is unknown and warrants further research.
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Affiliation(s)
- Danny Tsai
- Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Level 3, Ned Hanlon Building, Royal Brisbane and Women's Hospital, Herston, Brisbane, QLD, 4029, Australia
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Baietto L, Corcione S, Pacini G, Perri GD, D'Avolio A, De Rosa FG. A 30-years review on pharmacokinetics of antibiotics: is the right time for pharmacogenetics? Curr Drug Metab 2015; 15:581-98. [PMID: 24909419 PMCID: PMC4435065 DOI: 10.2174/1389200215666140605130935] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 04/17/2014] [Accepted: 05/21/2014] [Indexed: 12/28/2022]
Abstract
Drug bioavailability may vary greatly amongst individuals, affecting both efficacy and toxicity: in humans, genetic variations account for a relevant proportion of such variability. In the last decade the use of pharmacogenetics in clinical practice, as a tool to individualize treatment, has shown a different degree of diffusion in various clinical fields. In the field of infectious diseases, several studies identified a great number of associations between host genetic polymor-phisms and responses to antiretroviral therapy. For example, in patients treated with abacavir the screening for HLA-B*5701 before starting treatment is routine clinical practice and standard of care for all patients; efavirenz plasma levels are influenced by single nucleotide polymorphism (SNP) CYP2B6-516G> T (rs3745274). Regarding antibiotics, many studies investigated drug transporters involved in antibiotic bioavailability, especially for fluoroquinolones, cephalosporins, and antituberculars. To date, few data are available about pharmacogenetics of recently developed antibiotics such as tigecycline, daptomycin or linezolid. Considering the effect of SNPs in gene coding for proteins involved in antibiotics bioavailability, few data have been published. Increasing knowledge in the field of antibiotic pharmacogenetics could be useful to explain the high drug inter-patients variability and to individualize therapy. In this paper we reported an overview of pharmacokinetics, pharmacodynamics, and pharmacogenetics of antibiotics to underline the importance of an integrated approach in choosing the right dosage in clinical practice.
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Affiliation(s)
| | | | | | | | | | - Francesco Giuseppe De Rosa
- Department of Medical Sciences, University of Turin, Infectious Diseases at Amedeo di Savoia Hospital, Corso Svizzera 164, 10149. Turin, Italy.
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Lambrinidis G, Vallianatou T, Tsantili-Kakoulidou A. In vitro, in silico and integrated strategies for the estimation of plasma protein binding. A review. Adv Drug Deliv Rev 2015; 86:27-45. [PMID: 25819487 DOI: 10.1016/j.addr.2015.03.011] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 02/11/2015] [Accepted: 03/20/2015] [Indexed: 12/28/2022]
Abstract
Plasma protein binding (PPB) strongly affects drug distribution and pharmacokinetic behavior with consequences in overall pharmacological action. Extended plasma protein binding may be associated with drug safety issues and several adverse effects, like low clearance, low brain penetration, drug-drug interactions, loss of efficacy, while influencing the fate of enantiomers and diastereoisomers by stereoselective binding within the body. Therefore in holistic drug design approaches, where ADME(T) properties are considered in parallel with target affinity, considerable efforts are focused in early estimation of PPB mainly in regard to human serum albumin (HSA), which is the most abundant and most important plasma protein. The second critical serum protein α1-acid glycoprotein (AGP), although often underscored, plays also an important and complicated role in clinical therapy and thus the last years it has been studied thoroughly too. In the present review, after an overview of the principles of HSA and AGP binding as well as the structure topology of the proteins, the current trends and perspectives in the field of PPB predictions are presented and discussed considering both HSA and AGP binding. Since however for the latter protein systematic studies have started only the last years, the review focuses mainly to HSA. One part of the review highlights the challenge to develop rapid techniques for HSA and AGP binding simulation and their performance in assessment of PPB. The second part focuses on in silico approaches to predict HSA and AGP binding, analyzing and evaluating structure-based and ligand-based methods, as well as combination of both methods in the aim to exploit the different information and overcome the limitations of each individual approach. Ligand-based methods use the Quantitative Structure-Activity Relationships (QSAR) methodology to establish quantitate models for the prediction of binding constants from molecular descriptors, while they provide only indirect information on binding mechanism. Efforts for the establishment of global models, automated workflows and web-based platforms for PPB predictions are presented and discussed. Structure-based methods relying on the crystal structures of drug-protein complexes provide detailed information on the underlying mechanism but are usually restricted to specific compounds. They are useful to identify the specific binding site while they may be important in investigating drug-drug interactions, related to PPB. Moreover, chemometrics or structure-based modeling may be supported by experimental data a promising integrated alternative strategy for ADME(T) properties optimization. In the case of PPB the use of molecular modeling combined with bioanalytical techniques is frequently used for the investigation of AGP binding.
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Influence of surfactant and oil composition on the stability and antibacterial activity of eugenol nanoemulsions. Lebensm Wiss Technol 2015. [DOI: 10.1016/j.lwt.2015.01.012] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Wang H, Lee M, Peng Z, Blázquez B, Lastochkin E, Kumarasiri M, Bouley R, Chang M, Mobashery S. Synthesis and evaluation of 1,2,4-triazolo[1,5-a]pyrimidines as antibacterial agents against Enterococcus faecium. J Med Chem 2015; 58:4194-203. [PMID: 25923368 DOI: 10.1021/jm501831g] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Rapid emergence of antibiotic resistance is one of the most challenging global public health concerns. In particular, vancomycin-resistant Enterococcus faecium infections have been increasing in frequency, representing 25% of enterococci infections in intensive care units. A novel class of 1,2,4-triazolo[1,5-a]pyrimidines active against E. faecium is reported herein. We used a three-component Biginelli-like heterocyclization reaction for the synthesis of a series of these derivatives based on reactions of aldehydes, β-dicarbonyl compounds, and 3-alkylthio-5-amino-1,2,4-triazoles. The resulting compounds were assayed for antimicrobial activity against the ESKAPE panel of bacteria, followed by investigation of their in vitro activities. These analyses identified a subset of 1,2,4-triazolo[1,5-a]pyrimidines that had good narrow-spectrum antibacterial activity against E. faecium and exhibited metabolic stability with low intrinsic clearance. Macromolecular synthesis assays revealed cell-wall biosynthesis as the target of these antibiotics.
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Affiliation(s)
- Huan Wang
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Mijoon Lee
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Zhihong Peng
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Blas Blázquez
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Elena Lastochkin
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Malika Kumarasiri
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Renee Bouley
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Mayland Chang
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry and Eck Institute for Global Health, University of Notre Dame, 423 Nieuwland Hall, Notre Dame, Indiana 46556, United States
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Kim S, Lee H, Lee S, Yoon Y, Choi KH. Antimicrobial action of oleanolic acid on Listeria monocytogenes, Enterococcus faecium, and Enterococcus faecalis. PLoS One 2015; 10:e0118800. [PMID: 25756202 PMCID: PMC4355482 DOI: 10.1371/journal.pone.0118800] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 01/06/2015] [Indexed: 01/11/2023] Open
Abstract
This study investigated the antimicrobial action of oleanolic acid against Listeria monocytogenes, Enterococcus faecium, and Enterococcus faecalis. To determine the cytotoxicity of oleanolic acid, HEp-2 cells were incubated with oleanolic acid at 37oC. MICs (minimal inhibition concentrations) for L. monocytogenes, E. faecium, and E. faecalis were determined using two-fold microdilutions of oleanolic acid, and bacterial cell viability was then assessed by exposing the bacteria to oleanolic acid at 2 × MIC. To investigate the mode of antimicrobial action of oleanolic acid, we measured leakage of compounds absorbing at 280 nm, along with propidium iodide uptake. Scanning electron microscope (SEM) images were also analysed. The viability of HEp-2 cells decreased (P < 0.05) at oleanolic acid concentrations greater than 128 μg mL-1. The MICs were 16-32 μg mL-1 for L. monocytogenes and 32-64 μg mL-1 for E. faecium and E. faecalis, and bacterial cell viability decreased (P < 0.05) about 3-4 log CFU mL-1 after exposure to 2 × MIC of oleanolic acid. Leakage of 280 nm absorbing materials and propidium iodide uptake was higher in oleanolic acid –treated cells than in the control. The cell membrane was damaged in oleanolic acid-treated cells, but the control group had intact cell membrane in SEM images. The results indicate that oleanolic acid can kill L. monocytogenes, E. faecium, and E. faecalis by destroying the bacterial cell membrane.
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Affiliation(s)
- Sejeong Kim
- Department of Food and Nutrition, Sookmyung Women's University, Seoul, Korea
| | - Heeyoung Lee
- Department of Food and Nutrition, Sookmyung Women's University, Seoul, Korea
| | - Soomin Lee
- Department of Food and Nutrition, Sookmyung Women's University, Seoul, Korea
| | - Yohan Yoon
- Department of Food and Nutrition, Sookmyung Women's University, Seoul, Korea
- * E-mail: (YY); (KHC)
| | - Kyoung-Hee Choi
- Department of Oral Microbiology, College of Dentistry, Wonkwang University, Iksan, Jeonbuk, South Korea
- * E-mail: (YY); (KHC)
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Chanvorachote B, Qiu J, Muangsiri W, Nimmannit U, Kirsch LE. The interaction mechanism between lipopeptide (daptomycin) and polyamidoamine (PAMAM) dendrimers. J Pept Sci 2015; 21:312-9. [DOI: 10.1002/psc.2752] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/19/2014] [Accepted: 12/30/2014] [Indexed: 12/28/2022]
Affiliation(s)
- Boontarika Chanvorachote
- Pharmaceutical Technology (International) Program and Department of Pharmaceutics, Faculty of Pharmaceutical Sciences; Chulalongkorn University; Bangkok 10330 Thailand
| | - Jiang Qiu
- Division of Pharmaceutics, College of Pharmacy; The University of Iowa; Iowa City IA 52242 USA
| | - Walaisiri Muangsiri
- Pharmaceutical Technology (International) Program and Department of Pharmaceutics, Faculty of Pharmaceutical Sciences; Chulalongkorn University; Bangkok 10330 Thailand
| | - Ubonthip Nimmannit
- Pharmaceutical Technology (International) Program and Department of Pharmaceutics, Faculty of Pharmaceutical Sciences; Chulalongkorn University; Bangkok 10330 Thailand
- National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA); 111 Thailand Science Park, Phahonyothin Road, Klong 1 Klong Luang Pathumthani 12120 Thailand
| | - Lee E. Kirsch
- Division of Pharmaceutics, College of Pharmacy; The University of Iowa; Iowa City IA 52242 USA
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Spink E, Ding D, Peng Z, Boudreau MA, Leemans E, Lastochkin E, Song W, Lichtenwalter K, O'Daniel PI, Testero SA, Pi H, Schroeder VA, Wolter WR, Antunes NT, Suckow MA, Vakulenko S, Chang M, Mobashery S. Structure-activity relationship for the oxadiazole class of antibiotics. J Med Chem 2015; 58:1380-9. [PMID: 25590813 DOI: 10.1021/jm501661f] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structure-activity relationship (SAR) for the newly discovered oxadiazole class of antibiotics is described with evaluation of 120 derivatives of the lead structure. This class of antibiotics was discovered by in silico docking and scoring against the crystal structure of a penicillin-binding protein. They impair cell-wall biosynthesis and exhibit activities against the Gram-positive bacterium Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA) and vancomycin-resistant and linezolid-resistant S. aureus. 5-(1H-Indol-5-yl)-3-(4-(4-(trifluoromethyl)phenoxy)phenyl)-1,2,4-oxadiazole (antibiotic 75b) was efficacious in a mouse model of MRSA infection, exhibiting a long half-life, a high volume of distribution, and low clearance. This antibiotic is bactericidal and is orally bioavailable in mice. This class of antibiotics holds great promise in recourse against infections by MRSA.
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Affiliation(s)
- Edward Spink
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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Characterization of high-level daptomycin resistance in Viridans group Streptococci developed upon in vitro exposure to daptomycin. Antimicrob Agents Chemother 2015; 59:2102-12. [PMID: 25624330 DOI: 10.1128/aac.04219-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Viridans group streptococci (VGS) are part of the normal flora that may cause bacteremia, often leading to endocarditis. We evaluated daptomycin against four clinical strains of VGS (MICs = 1 or 2 μg/ml) using an in vitro-simulated endocardial vegetation model, a simulated bacteremia model, and kill curves. Daptomycin exposure was simulated at 6 mg/kg of body weight and 8 mg/kg every 24 h for endocardial and bacteremia models. Total drug concentrations were used for analyses containing protein (albumin and pooled human serum), and free (unbound) drug concentrations (93% protein bound) were used for analyses not containing protein. Daptomycin MICs in the presence of protein were significantly higher than those in the absence of protein. Despite MICs below or at the susceptible breakpoint, all daptomycin regimens demonstrated limited kill in both pharmacodynamic models. A reduction of approximately 1 to 2 log10 CFU was seen for all isolates and dosages except daptomycin at 6 mg/kg, which achieved a reduction of 2.7 log10 CFU/g against one strain (Streptococcus gordonii 1649) in the endocardial model. Activity was similar in both pharmacodynamic models in the presence or absence of protein. Similar activity was noted in the kill curves over all multiples of the MIC. Regrowth by 24 h was seen even at 8× MIC. Postexposure daptomycin MICs for both pharmacodynamic models increased to >256 μg/ml for all isolates by 24 and 72 h. Despite susceptibility to daptomycin by standard MIC methods, these VGS developed high-level daptomycin resistance (HLDR) after a short duration following drug exposure not attributed to modification or inactivation of daptomycin. Further evaluation is warranted to determine the mechanism of resistance and clinical implications.
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Pharmacokinetics and Pharmacodynamics of Antibacterial and Antifungal Agents in Adult Patients With Thermal Injury. J Burn Care Res 2015; 36:e72-84. [DOI: 10.1097/bcr.0000000000000147] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Enterococcus spp. are among the common pathogens causing infective endocarditis (IE). Despite major medical advances and new potent antimicrobial agents, the mortality has not significantly improved for several decades. The usual lack of bactericidal activity of penicillin or ampicillin, the toxicity from the combination of penicillin plus aminoglycosides, and the increased reports of high-level resistance to aminoglycosides have led to the exploration of other regimens for treatment of Enterococcus faecalis IE. As an example, ampicillin plus ceftriaxone is now a well-recognized regimen for this organism. However, the emerging of new drug resistances in Enterococcus faecium dramatically reduces the therapeutic alternatives for this organism in IE which continues to be an immense challenge for clinicians even with the availability of newer antimicrobial agents. This article summarizes the current treatment options for enterococcal endocarditis and reviews of recent publications on the topic.
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Haselden M, Leach M, Bohm N. Daptomycin dosing strategies in patients receiving thrice-weekly intermittent hemodialysis. Ann Pharmacother 2014; 47:1342-7. [PMID: 24259698 DOI: 10.1177/1060028013503110] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To determine the optimal dosing regimen of daptomycin in patients receiving thrice-weekly hemodialysis. DATA SOURCES Literature was accessed via PubMed using the terms daptomycin and hemodialysis through July 2013. Reference citations from publications identified were reviewed. STUDY SELECTION AND DATA EXTRACTION English language articles meeting the search criteria were evaluated. Studies were included if they addressed either thrice-weekly or intradialytic daptomycin administration. DATA SYNTHESIS Daptomycin is approved for the treatment of bloodstream infections due to methicillin-resistant Staphylococcus aureus and other Gram-positive organisms. Rapid bactericidal activity and limited potential for drug interactions make daptomycin an attractive agent. However, the daptomycin prescribing information recommends dosing every 48 hours in patients receiving hemodialysis, which results in dyssynchrony of dosing and dialysis sessions every other week. Studies evaluating a dosing regimen of daptomycin thrice weekly, coinciding with dialysis, indicate that pharmacokinetic and pharmacodynamic parameters are appropriate for therapeutic success. However, to maintain adequate serum drug concentrations throughout the 72-hour interdialytic period, an additional 50% of the dose should be provided to account for the longer interval. Intradialytic dosing, with the administration of daptomycin infusion beginning during the final 30 minutes of dialysis, may also require a dose increase. Limited clinical outcomes data have been reported, but no significant safety concerns have been identified. CONCLUSIONS Administration of daptomycin doses thrice weekly on hemodialysis days appears to be both safe and reasonable. Doses should be increased preceding the 72-hour interdialytic period or if daptomycin is infused during dialysis.
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Affiliation(s)
- Molly Haselden
- South Carolina College of Pharmacy/Medical University of South Carolina, Charleston, SC, USA
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Ceftriaxone for Methicillin-Sensitive Staphylococcus aureus Osteoarticular Infections. INFECTIOUS DISEASES IN CLINICAL PRACTICE 2014. [DOI: 10.1097/ipc.0000000000000109] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Perola E, Stamos D, Grillot AL, Ronkin S, Wang T, LeTiran A, Tang Q, Deininger DD, Liao Y, Tian SK, Drumm JE, Nicolau DP, Tessier PR, Mani N, Grossman TH, Charifson PS. Successful application of serum shift prediction models to the design of dual targeting inhibitors of bacterial gyrase B and topoisomerase IV with improved in vivo efficacy. Bioorg Med Chem Lett 2014; 24:2177-81. [PMID: 24685546 DOI: 10.1016/j.bmcl.2014.03.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 03/07/2014] [Indexed: 11/28/2022]
Abstract
A series of dual targeting inhibitors of bacterial gyrase B and topoisomerase IV were identified and optimized to mid-to-low nanomolar potency against a variety of bacteria. However, in spite of seemingly adequate exposure achieved upon IV administration, the in vivo efficacy of the early lead compounds was limited by high levels of binding to serum proteins. To overcome this limitation, targeted serum shift prediction models were generated for each subclass of interest and were applied to the design of prospective analogs. As a result, numerous compounds with comparable antibacterial potency and reduced protein binding were generated. These efforts culminated in the synthesis of compound 10, a potent inhibitor with low serum shift that demonstrated greatly improved in vivo efficacy in two distinct rat infection models.
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Affiliation(s)
- Emanuele Perola
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States.
| | - Dean Stamos
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Anne-Laure Grillot
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Steven Ronkin
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Tiansheng Wang
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Arnaud LeTiran
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Qing Tang
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - David D Deininger
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Yusheng Liao
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Shi-Kai Tian
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Joseph E Drumm
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - David P Nicolau
- Center for Anti-Infective Research and Development, Hartford Hospital, 80 Seymour Street, Hartford, CT 06102, United States
| | - Pamela R Tessier
- Center for Anti-Infective Research and Development, Hartford Hospital, 80 Seymour Street, Hartford, CT 06102, United States
| | - Nagraj Mani
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Trudy H Grossman
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
| | - Paul S Charifson
- Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210, United States
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Arias CA, Murray BE. Emergence and management of drug-resistant enterococcal infections. Expert Rev Anti Infect Ther 2014; 6:637-55. [DOI: 10.1586/14787210.6.5.637] [Citation(s) in RCA: 193] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Importance of relating efficacy measures to unbound drug concentrations for anti-infective agents. Clin Microbiol Rev 2013; 26:274-88. [PMID: 23554417 DOI: 10.1128/cmr.00092-12] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
For the optimization of dosing regimens of anti-infective agents, it is imperative to have a good understanding of pharmacokinetics (PK) and pharmacodynamics (PD). Whenever possible, drug efficacy needs to be related to unbound concentrations at the site of action. For anti-infective drugs, the infection site is typically located outside plasma, and a drug must diffuse through capillary membranes to reach its target. Disease- and drug-related factors can contribute to differential tissue distribution. As a result, the assumption that the plasma concentration of drugs represents a suitable surrogate of tissue concentrations may lead to erroneous conclusions. Quantifying drug exposure in tissues represents an opportunity to relate the pharmacologically active concentrations to an observed pharmacodynamic parameter, such as the MIC. Selection of an appropriate specimen to sample and the advantages and limitations of the available sampling techniques require careful consideration. Ultimately, the goal will be to assess the appropriateness of a drug and dosing regimen for a specific pathogen and infection.
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