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VanEperen AS, Segreti J. Empirical therapy in Methicillin-resistant Staphylococcus Aureus infections: An Up-To-Date approach. J Infect Chemother 2016; 22:351-9. [PMID: 27066882 DOI: 10.1016/j.jiac.2016.02.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 02/16/2016] [Indexed: 12/11/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) continues to be an important pathogen worldwide, with high prevalence of infection in both community and hospital settings. Timely and appropriate choice of empirical therapy in the setting of MRSA infection is imperative due to the high rate of associated morbidity and mortality with MRSA infections. Initial choices should be made based on the site and severity of the infection, most notably moderate skin and soft tissue infections which may be treated with oral antibiotics (trimethoprim-sulfamethoxazole, clindamycin, doxycycline/minocycline, linezolid) in the outpatient setting, versus choice of parenteral therapy in the inpatient setting of more invasive or severe disease. Though the current recommendations continue to strongly rely on vancomycin as a standard empiric choice in the setting of severe/invasive infections, alternative therapies exist with studies supporting their non-inferiority. This includes the use of linezolid in pneumonia and severe skin and skin structure infections (SSSI) and daptomycin for MRSA bacteremia, endocarditis, SSSIs and bone/joint infections. Additionally, concerns continue to arise in regards to vancomycin, such as increasing isolate MICs, and relatively high rates of clinical failures with vancomycin. Thus, the growing interest in vanomycin alternatives, such as ceftaroline, ceftobribole, dalbavancin, oritavancin, and tedizolid, and their potential role in treating MRSA infections.
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Affiliation(s)
- Alison S VanEperen
- Section of Infectious Diseases, Rush University Medical Center, 600 South Paulina, Suite 143 Armour Academic Facility, Chicago, IL 60612, USA
| | - John Segreti
- Section of Infectious Diseases, Rush University Medical Center, 600 South Paulina, Suite 143 Armour Academic Facility, Chicago, IL 60612, USA.
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Cheng M, Ziora ZM, Hansford KA, Blaskovich MA, Butler MS, Cooper MA. Anti-cooperative ligand binding and dimerisation in the glycopeptide antibiotic dalbavancin. Org Biomol Chem 2014; 12:2568-75. [PMID: 24608916 PMCID: PMC4082399 DOI: 10.1039/c3ob42428f] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/22/2014] [Indexed: 12/22/2022]
Abstract
Dalbavancin, a semi-synthetic glycopeptide with enhanced antibiotic activity compared to vancomycin and teicoplanin, binds to the C-terminal lysyl-d-alanyl-d-alanine subunit of Lipid II, inhibiting peptidoglycan biosynthesis. In this study, micro-calorimetry and electrospray ionization (ESI)-MS have been used to investigate the relationship between oligomerisation of dalbavancin and binding of a Lipid II peptide mimic, diacetyl-Lys-d-Ala-d-Ala (Ac2-Kaa). Dalbavancin dimerised strongly in an anti-cooperative manner with ligand-binding, as was the case for ristocetin A, but not for vancomycin and teicoplanin. Dalbavancin and ristocetin A both adopt an 'closed' conformation upon ligand binding, suggesting anti-cooperative dimerisation with ligand-binding may be a general feature of dalbavancin/ristocetin A-like glycopeptides. Understanding these effects may provide insight into design of novel dalbavancin derivatives with cooperative ligand-binding and dimerisation characteristics that could enhance antibiotic activity.
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Affiliation(s)
- Mu Cheng
- Division of Chemistry and Structural Biology , Institute for Molecular Bioscience , The University of Queensland , Brisbane , Queensland 4072 , Australia . ; Tel: +61-7-3346-2044
| | - Zyta M. Ziora
- Division of Chemistry and Structural Biology , Institute for Molecular Bioscience , The University of Queensland , Brisbane , Queensland 4072 , Australia . ; Tel: +61-7-3346-2044
| | - Karl A. Hansford
- Division of Chemistry and Structural Biology , Institute for Molecular Bioscience , The University of Queensland , Brisbane , Queensland 4072 , Australia . ; Tel: +61-7-3346-2044
| | - Mark A. Blaskovich
- Division of Chemistry and Structural Biology , Institute for Molecular Bioscience , The University of Queensland , Brisbane , Queensland 4072 , Australia . ; Tel: +61-7-3346-2044
| | - Mark S. Butler
- Division of Chemistry and Structural Biology , Institute for Molecular Bioscience , The University of Queensland , Brisbane , Queensland 4072 , Australia . ; Tel: +61-7-3346-2044
| | - Matthew A. Cooper
- Division of Chemistry and Structural Biology , Institute for Molecular Bioscience , The University of Queensland , Brisbane , Queensland 4072 , Australia . ; Tel: +61-7-3346-2044
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Loffler CA, MacDougall C. Update on prevalence and treatment of methicillin-resistantStaphylococcus aureusinfections. Expert Rev Anti Infect Ther 2014; 5:961-81. [DOI: 10.1586/14787210.5.6.961] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Zhanel GG, Trapp S, Gin AS, DeCorby M, Lagacé-Wiens PRS, Rubinstein E, Hoban DJ, Karlowsky JA. Dalbavancin and telavancin: novel lipoglycopeptides for the treatment of Gram-positive infections. Expert Rev Anti Infect Ther 2014; 6:67-81. [DOI: 10.1586/14787210.6.1.67] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Ohlsen K. Novel antibiotics for the treatment ofStaphylococcus aureus. Expert Rev Clin Pharmacol 2014; 2:661-72. [DOI: 10.1586/ecp.09.26] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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6
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Hao H, Cheng G, Dai M, Wu Q, Yuan Z. Inhibitors targeting on cell wall biosynthesis pathway of MRSA. MOLECULAR BIOSYSTEMS 2012; 8:2828-38. [DOI: 10.1039/c2mb25188d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bennett JW, Lewis JS, Ellis MW. Dalbavancin in the treatment of complicated skin and soft-tissue infections: a review. Ther Clin Risk Manag 2011; 4:31-40. [PMID: 18728718 PMCID: PMC2503664 DOI: 10.2147/tcrm.s46] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Increasing rates of antimicrobial resistance among strains of Streptococcus, Staphylococcus, and Enterococcus spp. have been widely documented. At least 50% of nosocomial Staphylococcus aureus infections in intensive care units in the US and UK are due methicillin-resistant S. aureus (MRSA). Drug resistance is not confined to hospitals, and community-acquired MRSA (CA-MRSA) strains are now common causes of complicated skin and soft-tissue infections (cSSTIs) in many regions. Dalbavancin is a novel parenterally administered semisynthetic lipoglycopeptide similar to the naturally produced glycopeptides vancomycin and teicoplanin. Dalbavancin features a multifaceted mechanism of action that inhibits bacterial cell wall formation by two different mechanisms that enhances its activity against a wide range of gram-positive bacteria including staphylococci, streptococci, enterococci, and some anaerobes. Additionally, dalbavancin possesses unique pharmacokinetic properties, the most significant of which is a long terminal half-life that allows for once weekly dosing. This attribute may prove to yield clinical and cost benefit. Overall, clinical trials indicate that dalbavancin is a safe, well-tolerated, and effective antimicrobial agent. In the largest investigation evaluating dalbavancin for the treatment of cSSTIs, it appeared to be as effective as linezolid. Dalbavancin, which is expected to receive FDA approval in 2008, appears to be a promising new antimicrobial agent for the treatment of cSSTIs.
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Affiliation(s)
- Jason W Bennett
- Department of Medicine-Infectious Disease Service, Brooke Army Medical Center Fort Sam Houston, TX, USA
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Esteban J, Cordero-Ampuero J. Treatment of prosthetic osteoarticular infections. Expert Opin Pharmacother 2011; 12:899-912. [DOI: 10.1517/14656566.2011.543676] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Huang V, Cheung CM, Kaatz GW, Rybak MJ. Evaluation of dalbavancin, tigecycline, minocycline, tetracycline, teicoplanin and vancomycin against community-associated and multidrug-resistant hospital-associated meticillin-resistant Staphylococcus aureus. Int J Antimicrob Agents 2010; 35:25-9. [DOI: 10.1016/j.ijantimicag.2009.08.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 08/19/2009] [Accepted: 08/20/2009] [Indexed: 11/29/2022]
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Reddy P, Chadaga S, Noskin GA. Antibiotic considerations in the treatment of multidrug-resistant (MDR) pathogens: a case-based review. J Hosp Med 2009; 4:E8-15. [PMID: 19670375 DOI: 10.1002/jhm.505] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The recent rise in antimicrobial resistance among health-care associated pathogens is a growing public health concern. According to the National Nosocomial Infections Surveillance System, rates of methicillin-resistant Staphylococcus aureus (MRSA) in intensive care units have nearly doubled over the last decade. Of equal importance, gram-negative agents such as Pseudomonas aeruginosa, Acinetobacter baumannii, and extended-spectrum beta lactamase-producing Enterobacteriaceae demonstrate increasing resistance to third-generation cephalosporins, fluoroquinolones, and, in some cases, carbapenems. As a consequence, hospitalists may find themselves utilizing new antibiotics in the treatment of bacterial infections. This case-based review will highlight 8 antibiotics that have emerging clinical indications in treating these multidrug-resistant (MDR) pathogens.
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Affiliation(s)
- Pavani Reddy
- Division of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA.
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Biedenbach DJ, Jones RN. Multicenter evaluation of the in vitro activity of dalbavancin tested against staphylococci and streptococci in 5 European countries: results from the DECIDE Surveillance Program (2007). Diagn Microbiol Infect Dis 2009; 64:177-84. [PMID: 19249179 DOI: 10.1016/j.diagmicrobio.2008.12.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Accepted: 03/02/2009] [Indexed: 10/21/2022]
Abstract
Dalbavancin is an antimicrobial lipoglycopeptide agent that has proven activity against Gram-positive pathogens and a once weekly dosing advantage compared with other agents in the glycopeptide class. The most common pathogens isolated from skin and skin structure infections (SSSIs) include Staphylococcus aureus and beta-hemolytic streptococci (betaHS), and dalbavancin has demonstrated excellent activity against these species. This study used 18 medical center laboratories in 5 European countries to assess the activity of dalbavancin, vancomycin, and teicoplanin against S. aureus, coagulase-negative staphylococci (CoNS), and betaHS. The rank order of potency was dalbavancin (MIC(50), 0.06 microg/mL) > teicoplanin (MIC(50), 0.5 microg/mL) > vancomycin (MIC(50), 2 microg/mL) and dalbavancin (MIC(50), 0.06 microg/mL) > teicoplanin and vancomycin (MIC(50), 2 microg/mL) against S. aureus and CoNS, respectively. Dalbavancin was the most active glycopeptide tested against betaHS with all strains inhibited by < or = 0.12 microg/mL. Susceptibility to other antimicrobial classes was also evaluated with noticeable differences demonstrated between countries. Higher methicillin-resistant S. aureus (MRSA) rates were observed in Italy (44.2%) and the United Kingdom (36.8%) compared with other countries, but resistance to erythromycin (51.6-83.1%) and clindamycin (5.7-68.4%) among MRSA also varied significantly between countries. The excellent contemporary activity of dalbavancin against common Gram-positive pathogens collected in European countries suggests that dalbavancin could have a role in the treatment of various types of SSSIs.
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Activities of dalbavancin against a worldwide collection of 81,673 gram-positive bacterial isolates. Antimicrob Agents Chemother 2009; 53:1260-3. [PMID: 19124664 DOI: 10.1128/aac.01453-08] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dalbavancin, a long-acting lipoglycopeptide, was evaluated against 81,673 isolates of staphylococci, enterococci, and streptococci collected from 33 countries during worldwide resistance surveillance (2002 to 2007). Regardless of susceptibility to oxacillin, comparable potencies for dalbavancin against Staphylococcus aureus and coagulase-negative staphylococci from all countries were noted (MIC(90), 0.06 to 0.12 microg/ml). Vancomycin-susceptible Enterococcus spp. had dalbavancin MIC(90)s comparable to those for staphylococci, whereas vancomycin-resistant strains were more resistant (MIC(50), >4 microg/ml). beta-Hemolytic and viridians group streptococci were very susceptible to dalbavancin (MIC(90), <or=0.03 microg/ml). Overall, dalbavancin was >or=16-fold more active than vancomycin against the monitored gram-positive species.
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The Burden of Bacterial and Viral Infections in Hematopoietic Stem Cell Transplant. Biol Blood Marrow Transplant 2009; 15:128-33. [DOI: 10.1016/j.bbmt.2008.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Peppard WJ, Johnston CJ, Urmanski AM. Pharmacologic options for CNS infections caused by resistant Gram-positive organisms. Expert Rev Anti Infect Ther 2008; 6:83-99. [PMID: 18251666 DOI: 10.1586/14787210.6.1.83] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Infectious disease continues to evolve, presenting new and challenging clinical situations for practitioners. Specific to device-related and neurosurgical-related CNS infections, Gram-positive organisms are of growing concern. Current Infection Disease Society of America guidelines for the treatment of CNS infections offer little direction after conventional therapy, consisting of vancomycin, has failed or the patient has demonstrated intolerance. A review of literature evaluating alternative therapies, specifically linezolid, quinupristin/dalfopristin, daptomycin and tigecycline, will be presented. Interpretations of these data are offered followed by a brief presentation of future therapies, including ortavancin, telavancin, dalbavancin, ceftobiprole and iclaprim, all of which possess potent Gram-positive activity.
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Affiliation(s)
- William J Peppard
- Clinical Pharmacist, Surgical Critical Care, Froedtert Hospital, 9200 West, Wisconsin Avenue, Milwaukee, WI 53226, USA.
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Saravolatz LD, Billeter M, Zervos MJ, Chen AY, Dalovisio JR, Kurukularatne C. Dalbavancin: a Novel Once-Weekly Lipoglycopeptide Antibiotic. Clin Infect Dis 2008; 46:577-83. [DOI: 10.1086/526772] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Poulakou G, Giamarellou H. Oritavancin: a new promising agent in the treatment of infections due to Gram-positive pathogens. Expert Opin Investig Drugs 2008; 17:225-43. [DOI: 10.1517/13543784.17.2.225] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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17
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Omar NS, El-Nahas MR, Gray J. Novel antibiotics for the management of diabetic foot infections. Int J Antimicrob Agents 2007; 31:411-9. [PMID: 18155884 DOI: 10.1016/j.ijantimicag.2007.10.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Accepted: 10/17/2007] [Indexed: 11/24/2022]
Abstract
Foot infections are a major cause of morbidity in diabetic patients. Staphylococcus aureus is the most important pathogen in mild infections; moderate to severe infections are frequently polymicrobial. Multidrug resistance is an increasing problem in isolates from diabetic feet. Worldwide, up to 30% of patients with diabetic foot infection (DFI) are colonised with methicillin-resistant S. aureus (MRSA), whilst extended-spectrum beta-lactamase-producing Gram-negative bacteria are also common in some countries. This emergence of drug resistance has coincided with the launch or imminent availability of many new antibiotics. Most of these were developed to target multidrug-resistant Gram-positive bacteria, although some have a spectrum of activity that includes Gram-negative bacteria and anaerobes. There is a variable amount of experience with these agents in treating skin and skin-structure infections (SSSIs), especially for DFI. However, at least some have a spectrum of activity and/or pharmacological properties that suggest that they may be of value in managing DFIs. The aim of this paper is to review evidence for the efficacy of new antibiotics in the management of SSSIs, including any data relating specifically to the diabetic foot, and to consider where they might fit into the therapeutic armory against DFI.
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Affiliation(s)
- Nesrene S Omar
- Medical Microbiology & Immunology Department, Faculty of Medicine, Mansoura University, Egypt.
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Stein GE. New drugs to treat skin and soft tissue infections. Curr Infect Dis Rep 2007; 9:408-14. [PMID: 17880852 DOI: 10.1007/s11908-007-0063-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Due to increasing antimicrobial resistance, a pressing need exists for new antibiotics to treat skin and soft tissue infections. Several newer agents such as tigecycline, daptomycin, and linezolid have been important additions for the treatment of multidrug-resistant pathogens. New drugs in development such as dalbavancin and ceftobiprole will further enhance our ability to treat mixed infections and improve patient compliance. These promising new antimicrobials will likely grow in importance as resistant bacterial strains increase in community-acquired infections.
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Affiliation(s)
- Gary E Stein
- Department of Medicine, Michigan State University, B320 Life Sciences, East Lansing, MI 48824, USA.
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Micek ST. Alternatives to Vancomycin for the Treatment of Methicillin-Resistant Staphylococcus aureus Infections. Clin Infect Dis 2007; 45 Suppl 3:S184-90. [PMID: 17712745 DOI: 10.1086/519471] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Vancomycin remains the reference standard for the treatment of systemic infection caused by methicillin-resistant Staphylococcus aureus (MRSA). However, as a result of limited tissue distribution, as well as the emergence of isolates with reduced susceptibility and in vitro resistance to vancomycin, the need for alternative therapies that target MRSA has become apparent. New treatment options for invasive MRSA infections include linezolid, daptomycin, tigecycline, and quinupristin/dalfopristin. Additionally, a number of new anti-MRSA compounds are in development, including novel glycopeptides (dalbavancin, telavancin, and oritavancin), ceftobiprole, and iclaprim. The present article will review clinical issues surrounding the newly marketed and investigational agents with activity against MRSA.
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Affiliation(s)
- Scott T Micek
- Department of Pharmacy, Barnes-Jewish Hospital, St. Louis, MO, USA.
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Andes D, Craig WA. In vivo pharmacodynamic activity of the glycopeptide dalbavancin. Antimicrob Agents Chemother 2007; 51:1633-42. [PMID: 17307987 PMCID: PMC1855559 DOI: 10.1128/aac.01264-06] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dalbavancin is a lipoglycopeptide antibiotic with broad-spectrum activity against gram-positive cocci and a markedly prolonged serum elimination half-life. We used the neutropenic murine thigh and lung infection models to characterize the pharmacodynamics of dalbavancin. Single-dose pharmacokinetic studies demonstrated linear kinetics and a prolonged elimination half-life which ranged from 7.6 to 13.1 h over the dose range of 2.5 to 80 mg/kg of body weight. The level of protein binding in mouse serum was 98.4%. The time course of in vivo activity of dalbavancin over the same dose range was examined in neutropenic ICR Swiss mice infected with a strain of either Streptococcus pneumoniae or Staphylococcus aureus by using the thigh infection model. The burden of organisms for S. pneumoniae was markedly reduced over the initial 24 h of study, and organism regrowth was suppressed in a dose-dependent fashion for up to the entire 96 h of study following dalbavancin doses of 2.5 mg/kg or greater. Dalbavancin doses of 20 mg/kg or greater resulted in less killing of S. aureus but were still followed by a prolonged suppression of regrowth. Multiple-dosing-regimen studies with the same organisms were used to determined which of the pharmacodynamic indices (maximum concentration in serum [C(max)]/MIC, area under the concentration-versus-time curve [AUC]/MIC, or the duration of time that levels in serum exceed the MIC) best correlated with treatment efficacy. These studies used a dose range of 3.8 to 480 mg/kg/6 days fractionated into 2, 4, 6, or 12 doses over the 144-h dosing period. Nonlinear regression analysis was used to examine the data fit with each pharmacodynamic index. Dalbavancin administration by the use of large, widely spaced doses was the most efficacious for both organisms. Both the 24-h AUC/MIC and the C(max)/MIC parameters correlated well with the in vivo efficacy of treatment against S. pneumoniae and S. aureus (for 24-h AUC/MIC, R(2) = 78 and 77%, respectively; for C(max)/MIC, R(2) = 90 and 57%, respectively). The free-drug 24-h AUC/MICs required for a bacteriostatic effect were 17 +/- 7 for five S. pneumoniae isolates. A similar treatment endpoint for the treatment against five strains of S. aureus required a larger dalbavancin exposure, with a mean free-drug 24-h AUC/MIC of 265 +/- 143. Beta-lactam resistance did not affect the pharmacodynamic target. The dose-response curves were relatively steep for both species; thus, the pharmacodynamic target needed to achieve organism reductions of 1 or 2 log(10) in the mice were not appreciably larger (1.3- to 1.6-fold). Treatment was similarly efficacious in neutropenic mice and in the lung infection model. The dose-dependent efficacy and prolonged elimination half-life of dalbavancin support the widely spaced regimens used in clinical trials. The free-drug 24-h AUC/MIC targets identified in these studies should be helpful for discerning rational susceptibility breakpoints. The current MIC(90) for the target gram-positive organisms would fall within this value.
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Affiliation(s)
- David Andes
- Department of Medicine, University of Wisconsin, Madison, WI 53792, USA.
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Biedenbach DJ, Ross JE, Fritsche TR, Sader HS, Jones RN. Activity of dalbavancin tested against Staphylococcus spp. and beta-hemolytic Streptococcus spp. isolated from 52 geographically diverse medical centers in the United States. J Clin Microbiol 2007; 45:998-1004. [PMID: 17215346 PMCID: PMC1829082 DOI: 10.1128/jcm.02368-06] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dalbavancin is a lipoglycopeptide antimicrobial agent with a potency significantly better than that of vancomycin when tested against staphylococci and streptococci. These two pathogens are common causes of skin and skin structure infections (SSSIs), and dalbavancin has been approved for the treatment of moderate to severe SSSIs. This study generated susceptibility data for staphylococci and beta-hemolytic streptococci from 52 U.S. medical centers that locally tested dalbavancin, vancomycin, and other antimicrobial class representatives to assess the potency of dalbavancin and the overall contemporary activities of commonly prescribed agents. Locally generated data showed that oxacillin-resistant staphylococci (57.0% overall) had slightly higher dalbavancin MIC(90) values (0.19 microg/ml) than oxacillin-susceptible strains (0.125 microg/ml). This potency was 8- to 16-fold greater than that for vancomycin. beta-Hemolytic streptococci had MIC(90) values ranging between <or=0.016 and 0.064 microg/ml (highest for group B isolates). Levofloxacin, gentamicin, and tetracycline were active against oxacillin-susceptible staphylococci (82 to 99% susceptible), with lower susceptibility rates seen for the oxacillin-resistant strains. Linezolid coverage was >98% against staphylococci. Erythromycin resistance was high for staphylococci (30.6 to 94.1%) with inducible clindamycin resistance rates of 26.0% and 55.0% for oxacillin-susceptible and -resistant Staphylococcus aureus, respectively. Beta-hemolytic streptococci had a 20.2% erythromycin resistance rate and a 60% inducible clindamycin resistance rate but were highly susceptible to other tested agents. Etest reading errors were apparent and skewed results towards slightly higher dalbavancin MICs, requiring further education on how to interpret Etest method results for this compound. Current disk diffusion breakpoint criteria for oxacillin susceptibility for S. aureus showed a very-major-error rate of 2.3% and only a 0.9% minor-error rate when cefoxitin was used to predict oxacillin susceptibility. Dalbavancin demonstrated excellent potency and activity (100% susceptibility at proposed breakpoints) against common causes of SSSI pathogens in this U.S. multicenter study sample.
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Affiliation(s)
- Douglas J Biedenbach
- JMI Laboratories, 345 Beaver Kreek Centre, Suite A, North Liberty, IA 52317, USA.
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