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1.
Microb Cell Fact ; 23(1): 186, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943174

RESUMEN

BACKGROUND: Oritavancin is a new generation of semi-synthetic glycopeptide antibiotics against Gram-positive bacteria, which served as the first and only antibiotic with a single-dose therapeutic regimen to treat ABSSSI. A naturally occurring glycopeptide A82846B is the direct precursor of oritavancin. However, its application has been hampered by low yields and homologous impurities. This study established a multi-step combinatorial strategy to rationally construct a high-quality and high-efficiency biosynthesis system for A82846B and systematically optimize its fermentation process to break through the bottleneck of microbial fermentation production. RESULTS: Firstly, based on the genome sequencing and analysis, we deleted putative competitive pathways and constructed a better A82846B-producing strain with a cleaner metabolic background, increasing A82846B production from 92 to 174 mg/L. Subsequently, the PhiC31 integrase system was introduced based on the CRISPR-Cas12a system. Then, the fermentation level of A82846B was improved to 226 mg/L by over-expressing the pathway-specific regulator StrR via the constructed PhiC31 system. Furthermore, overexpressing glycosyl-synthesis gene evaE enhanced the production to 332 mg/L due to the great conversion of the intermediate to target product. Finally, the scale-up production of A82846B reached 725 mg/L in a 15 L fermenter under fermentation optimization, which is the highest reported yield of A82846B without the generation of homologous impurities. CONCLUSION: Under approaches including blocking competitive pathways, inserting site-specific recombination system, overexpressing regulator, overexpressing glycosyl-synthesis gene and optimizing fermentation process, a multi-step combinatorial strategy for the high-level production of A82846B was developed, constructing a high-producing strain AO-6. The combinatorial strategies employed here can be widely applied to improve the fermentation level of other microbial secondary metabolites, providing a reference for constructing an efficient microbial cell factory for high-value natural products.


Asunto(s)
Amycolatopsis , Fermentación , Ingeniería Metabólica , Amycolatopsis/metabolismo , Amycolatopsis/genética , Ingeniería Metabólica/métodos , Sistemas CRISPR-Cas , Antibacterianos/biosíntesis , Vías Biosintéticas , Glicopéptidos/biosíntesis
2.
BMC Infect Dis ; 24(1): 127, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267844

RESUMEN

BACKGROUND: Oritavancin, a long-acting lipoglycopeptide approved for use in acute bacterial skin and skin structure infections, has limited data evaluating use in serious infections due to Gram-positive organisms. We aimed to assess the effectiveness and safety of oritavancin for consolidative treatment of Gram-positive bloodstream infections (BSI), including infective endocarditis (IE). METHODS: We conducted a retrospective cohort study evaluating adult patients admitted to University of Colorado Hospital from March 2016 to January 2022 who received ≥ 1 oritavancin dose for treatment of Gram-positive BSI. Patients were excluded if the index culture was drawn at an outside facility or were > 89 years of age. The primary outcome was a 90-day composite failure (clinical or microbiological failure) in those with 90-day follow-up. Secondary outcomes included individual components of the primary outcome, acute kidney injury (AKI), infusion-related reactions (IRR), and institutional cost avoidance. RESULTS: Overall, 72 patients were included. Mean ± SD age was 54 ± 16 years, 61% were male, and 10% had IE. Organisms most commonly causing BSI were Staphylococcus aureus (68%, 17% methicillin-resistant), followed by Streptococcus spp. (26%), and Enterococcus spp. (10%). Patients received standard-of-care antibiotics before oritavancin for a median (IQR) of 11 (5-17) days. Composite failure in the clinically evaluable population (n = 64) at 90-days occurred in 14% and was composed of clinical and microbiological failure, which occurred in 14% and 5% of patients, respectively. Three patients (4%) experienced AKI after oritavancin, and two (3%) experienced an IRR. Oritavancin utilization resulted in earlier discharge for 94% of patients corresponding to an institutional cost-avoidance of $3,055,804 (mean $44,938/patient) from 1,102 hospital days saved (mean 16 days/patient). CONCLUSIONS: The use of oritavancin may be an effective sequential therapy for Gram-positive BSI to facilitate early discharge resulting in institutional cost avoidance.


Asunto(s)
Lesión Renal Aguda , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Endocarditis Bacteriana , Endocarditis , Vancomicina/análogos & derivados , Adulto , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Lipoglucopéptidos/uso terapéutico , Estudios Retrospectivos
3.
Ann Clin Microbiol Antimicrob ; 23(1): 60, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965559

RESUMEN

BACKGROUND: Gram-negative bacteria (GNB) are becoming increasingly resistant to a wide variety of antibiotics. There are currently limited treatments for GNB, and the combination of antibiotics with complementary mechanisms has been reported to be a feasible strategy for treating GNB infection. The inability to cross the GNB outer membrane (OM) is an important reason that a broad spectrum of Gram-positive only class of antibiotics (GPOAs) is lacking. Polymyxins may help GPOAs to permeate by disrupting OM of GNB. OBJECTIVE: To identify what kind of GPOAs can be aided to broaden their anti-GNB spectrum by polymyxins, we systematically investigated the synergy of eight GPOAs in combination with colistin (COL) and polymyxin B (PMB) against GNB in vitro. METHODS: The synergistic effect of COL or PMB and GPOAs combinations against GNB reference strains and clinical isolates were determined by checkerboard tests. The killing kinetics of the combinations were assessed using time-kill assays. RESULTS: In the checkerboard tests, polymyxins-GPOAs combinations exert synergistic effects characterized by species and strain specificity. The synergistic interactions on P. aeruginosa strains are significantly lower than those on strains of A. baumannii, K. pneumoniae and E. coli. Among all the combinations, COL has shown the best synergistic effect in combination with dalbavancin (DAL) or oritavancin (ORI) versus almost all of the strains tested, with FICIs from 0.16 to 0.50 and 0.13 to < 0.28, respectively. In addition, the time-kill assays demonstrated that COL/DAL and COL/ORI had sustained bactericidal activity. CONCLUSIONS: Our results indicated that polymyxins could help GPOAs to permeate the OM of specific GNB, thus showed synergistic effects and bactericidal effects in the in vitro assays. In vivo combination studies should be further conducted to validate the results of this study.


Asunto(s)
Antibacterianos , Colistina , Sinergismo Farmacológico , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Polimixina B , Polimixinas , Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Polimixinas/farmacología , Polimixina B/farmacología , Humanos , Colistina/farmacología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos
4.
Antimicrob Agents Chemother ; 66(6): e0261420, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35475634

RESUMEN

The long-acting lipoglycopeptides (LGPs) dalbavancin and oritavancin are semisynthetic antimicrobials with broad and potent activity against Gram-positive bacterial pathogens. While they are approved by the Food and Drug Administration for acute bacterial skin and soft tissue infections, their pharmacological properties suggest a potential role of these agents for the treatment of deep-seated and severe infections, such as bloodstream and bone and joint infections. The use of these antimicrobials is particularly appealing when prolonged therapy, early discharge, and avoidance of long-term intravascular catheter access are desirable or when multidrug-resistant bacteria are suspected. This review describes the current evidence for the use of oritavancin and dalbavancin in the treatment of invasive infections, as well as the hurdles that are preventing their optimal use. Moreover, this review discusses the current knowledge gaps that need to be filled to understand the potential role of LGPs in highly needed clinical scenarios and the ongoing clinical studies that aim to address these voids in the upcoming years.


Asunto(s)
Antiinfecciosos , Infecciones por Bacterias Grampositivas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Glicopéptidos/química , Glicopéptidos/farmacología , Glicopéptidos/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Humanos , Lipoglucopéptidos/uso terapéutico , Teicoplanina/farmacología , Teicoplanina/uso terapéutico
5.
Ann Clin Microbiol Antimicrob ; 21(1): 37, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35978400

RESUMEN

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) infections are considered an important public health problem, and treatment options are limited. Accordingly, in this meta-analysis, we analyzed published studies to survey in vitro activity of recently approved antibiotics against MRSA isolates. METHODS: We searched electronic databases; PubMed, Scopus, and Web of Science to identify relevant studies (until November 30, 2020) that have focused on the in vitro activity of telavancin, dalbavancin, oritavancin, and tedizolid against MRSA isolates. Statistical analyses were conducted using STATA software (version 14.0). RESULTS: Thirty-eight studies were included in this meta-analysis. Overall in vitro activity of tedizolid on 12,204 MRSA isolates was 0.250 and 0.5 µg/mL for MIC50 and MIC90, (minimum inhibitory concentration at which 50% and 90% of isolates were inhibited, respectively), respectively. The overall antibacterial activity of dalbavancin on 28539 MRSA isolates was 0.060 and 0.120 µg/mL for MIC50 and MIC90, respectively. The overall antibacterial activity of oritavancin on 420 MRSA isolates was 0.045 and 0.120 µg/mL for MIC50 and MIC90, respectively. The overall antibacterial activity of telavancin on 7353 MRSA isolates was 0.032 and 0.060 µg/mL for MIC50 and MIC90, respectively. The pooled prevalence of tedizolid, telavancin, and dalbavancin susceptibility was 100% (95% CI: 100-100). CONCLUSION: Telavancin, dalbavancin, oritavancin, and tedizolid had potent in vitro activity against MRSA isolates. The low MICs and high susceptibility rates of these antibiotics recommend a hopeful direction to introduce useful antibiotics in treating MRSA infections in the future.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología
6.
Am J Emerg Med ; 43: 77-80, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33545550

RESUMEN

Skin and soft tissue infections, such as cellulitis, are commonly diagnosed in the emergency department and these patients are often admitted to the hospital for intravenous antibiotic therapy. Oritavancin is a novel antibiotic approved for the treatment of skin and soft tissue infections that is administered as a one-time infusion. While oritavancin has demonstrated comparable efficacy with multi-dose parenteral antibiotics in clinical trials and has been proposed as an alternative to admission for emergency department patients, there is a paucity of available real world effectiveness data. In this case series, we describe the characteristics and outcomes of ten patients with high-risk skin and soft tissue infections who received oritavancin and were discharged from the emergency department.


Asunto(s)
Antibacterianos/administración & dosificación , Celulitis (Flemón)/tratamiento farmacológico , Lipoglucopéptidos/administración & dosificación , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Servicio de Urgencia en Hospital , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
7.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34198513

RESUMEN

BACKGROUND: Pulmonary disease caused by Mycobacterium abscessus (M. abscessus) spreads around the world, and this disease is extremely difficult to treat due to intrinsic and acquired resistance of the pathogen to many approved antibiotics. M. abscessus is regarded as one of the most drug-resistant mycobacteria, with very limited therapeutic options. METHODS: Whole-cell growth inhibition assays was performed to screen and identify novel inhibitors. The IC50 of the target compounds were tested against THP-1 cells was determined to calculate the selectivity index, and then time-kill kinetics assay was performed against M. abscessus. Subsequently, the synergy of oritavancin with other antibiotics was evaluated by using checkerboard method. Finally, in vivo efficacy was determined in an immunosuppressive murine model simulating M. abscessus infection. RESULTS: We have identified oritavancin as a potential agent against M. abscessus. Oritavancin exhibited time-concentration dependent bactericidal activity against M. abscessus and it also displayed synergy with clarithromycin, tigecycline, cefoxitin, moxifloxacin, and meropenem in vitro. Additionally, oritavancin had bactericidal effect on intracellular M. abscessus. Oritavancin significantly reduced bacterial load in lung when it was used alone or in combination with cefoxitin and meropenem. CONCLUSIONS: Our in vitro and in vivo assay results indicated that oritavancin may be a viable treatment option against M. abscessus infection.


Asunto(s)
Antibacterianos/uso terapéutico , Lipoglucopéptidos/uso terapéutico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Mycobacterium abscessus/fisiología , Animales , Antibacterianos/farmacología , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Humanos , Terapia de Inmunosupresión , Espacio Intracelular/microbiología , Lipoglucopéptidos/farmacología , Ratones , Pruebas de Sensibilidad Microbiana , Mycobacterium abscessus/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Células THP-1
8.
Am J Emerg Med ; 38(2): 321-324, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31839519

RESUMEN

INTRODUCTION: Cellulitis is commonly treated in the emergency department (ED). Oritavancin is a novel, broad-spectrum antibiotic which provides an entire treatment course for cellulitis with one dose. However, optimal ED prescribing scenarios for oritavancin have not been well defined. The purpose of this study was to identify a population of ED patients with cellulitis who would be most appropriate to receive oritavancin. METHODS: This was a descriptive, retrospective study conducted at a Midwest healthcare system with two EDs. Over a 1 year period, all adult patients admitted from the ED to an inpatient ward with an ICD-10 diagnosis for cellulitis were reviewed using a priori defined criteria to identify potentially avoidable admissions (PAA). Potentially avoidable admissions were further characterized and compared to the non-avoidable admission population. Identified patient-specific criteria for PAAs were used to develop oritavancin inclusion/exclusion criteria and a case selection flowchart. RESULTS: Eighty-six patients were identified during the study period. Nine patients (10.5%) were deemed a PAA. A majority of the PAA population had at least one risk factor for treatment failure (55% with diabetes mellitus) and this group was significantly younger than the non-PAA group (42.2 vs 58.6 years; P = 0.01). There were no differences between the PAA group and the non-PAA group in regard to non-age demographics, other risk factors for outpatient treatment failure, comorbidities, or length of stay. CONCLUSION: Oritavancin is an outpatient treatment alternative for cellulitis patients whose only justification for planned admission is the presence of one or more risk factors for treatment failure.


Asunto(s)
Antibacterianos/uso terapéutico , Celulitis (Flemón)/tratamiento farmacológico , Servicio de Urgencia en Hospital/organización & administración , Lipoglucopéptidos/uso terapéutico , Admisión del Paciente/estadística & datos numéricos , Administración Intravenosa , Adulto , Celulitis (Flemón)/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medio Oeste de Estados Unidos , Estudios Retrospectivos , Insuficiencia del Tratamiento
9.
Artículo en Inglés | MEDLINE | ID: mdl-31235559

RESUMEN

Weekly oritavancin plus ampicillin continuous infusion combination therapy was used to successfully treat a deep spine vancomycin-resistant Enterococcus faecium infection associated with hardware. Checkerboard and time-kill assays confirmed synergy between these two antibiotics. Further synergies of oritavancin and ampicillin with rifampin or the endogenous human antimicrobial peptide cathelicidin LL-37 were demonstrated.


Asunto(s)
Ampicilina/uso terapéutico , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Enterococcus faecium/efectos de los fármacos , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Lipoglucopéptidos/uso terapéutico , Osteomielitis/tratamiento farmacológico , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Antibacterianos/uso terapéutico , Sinergismo Farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Vancomicina/uso terapéutico
10.
Artículo en Inglés | MEDLINE | ID: mdl-30012765

RESUMEN

The antibiofilm activity of oritavancin in combination with rifampin, gentamicin, or linezolid was evaluated against 10 prosthetic joint infection (PJI)-related methicillin-resistant Staphylococcus aureus (MRSA) isolates by time-kill assays. Oritavancin combined with rifampin demonstrated statistically significant bacterial reductions compared with those of either antimicrobial alone for all 10 isolates (P ≤ 0.001), with synergy being observed for 80% of the isolates. Oritavancin and rifampin combination therapy may be an option for treating MRSA PJI.


Asunto(s)
Biopelículas/efectos de los fármacos , Gentamicinas/farmacología , Linezolid/farmacología , Lipoglucopéptidos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Rifampin/farmacología , Pruebas de Sensibilidad Microbiana
11.
Artículo en Inglés | MEDLINE | ID: mdl-29109163

RESUMEN

The clinical development of nonsusceptibility to the lipopeptide antibiotic daptomycin remains a serious concern during therapy for infections caused by vancomycin-resistant Enterococcus faecium (VREfm). The long-acting lipoglycopeptide oritavancin exhibits potent in vitro activity against VREfm, although its safety and efficacy for treating clinical VREfm infections have not been established. In this study, novel dosing regimens of daptomycin and oritavancin were assessed against both VREfm and daptomycin-nonsusceptible VREfm isolates in an in vitro pharmacokinetic/pharmacodynamic model.


Asunto(s)
Antibacterianos/farmacología , Daptomicina/farmacología , Enterococcus faecium/efectos de los fármacos , Lipoglucopéptidos/farmacología , Resistencia a la Vancomicina/efectos de los fármacos , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Vancomicina/farmacología , Daptomicina/farmacocinética , Glicopéptidos/farmacocinética , Glicopéptidos/farmacología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Humanos , Lipoglucopéptidos/farmacocinética , Pruebas de Sensibilidad Microbiana/métodos , Vancomicina/farmacocinética
12.
J Bacteriol ; 199(15)2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28507244

RESUMEN

Oritavancin is a lipoglycopeptide antibiotic that exhibits potent activities against vancomycin-resistant Gram-positive pathogens. Oritavancin differs from vancomycin by a hydrophobic side chain attached to the drug disaccharide, which forms a secondary binding site to enable oritavancin binding to the cross-linked peptidoglycan in the cell wall. The mode of action of secondary binding site was investigated by measuring the changes in the peptidoglycan composition of Staphylococcus aureus grown in the presence of desleucyl-oritavancin at subinhibitory concentration using liquid chromatography-mass spectrometry (LC-MS). Desleucyl-oritavancin is an Edman degradation product of oritavancin that exhibits potent antibacterial activities despite the damaged d-Ala-d-Ala binding site due to its functional secondary binding site. Accurate quantitative peptidoglycan composition analysis based on 83 muropeptide ions determined that cell walls of S. aureus grown in the presence of desleucyl-oritavancin showed a reduction of peptidoglycan cross-linking, increased muropeptides with a tetrapeptide-stem structure, decreased O-acetylation of MurNAc, and increased N-deacetylation of GlcNAc. The changes in peptidoglycan composition suggest that desleucyl-oritavancin targets the peptidoglycan template to induce cell wall disorder and interferes with cell wall maturation.IMPORTANCE Oritavancin is a lipoglycopeptide antibiotic with a secondary binding site that targets the cross-linked peptidoglycan bridge structure in the cell wall. Even after the loss of its primary d-Ala-d-Ala binding site through Edman degradation, desleucyl-oritavancin exhibits potent antimicrobial activities through its still-functioning secondary binding site. In this study, we characterized the mode of action for desleucyl-oritavancin's secondary binding site using LC-MS. Peptidoglycan composition analysis of desleucyl-oritavancin-treated S. aureus was performed by determining the relative abundances of 83 muropeptide ions matched from a precalculated library through integrating extracted ion chromatograms. Our work highlights the use of quantitative peptidoglycan composition analysis by LC-MS to provide insights into the mode of action of glycopeptide antibiotics.


Asunto(s)
Antibacterianos/farmacología , Pared Celular/química , Pared Celular/efectos de los fármacos , Glicopéptidos/farmacología , Peptidoglicano/análisis , Staphylococcus aureus/efectos de los fármacos , Cromatografía Liquida , Lipoglucopéptidos , Espectrometría de Masas
13.
Artículo en Inglés | MEDLINE | ID: mdl-27956417

RESUMEN

Previous studies have shown that some lipoglycopeptide and lipopeptide antimicrobial agents may cause falsely elevated values for some phospholipid-dependent coagulation tests. The effect of oritavancin, a lipoglycopeptide antibiotic, on coagulation test results was explored using pooled human plasma samples spiked with drug and in a clinical study after an infusion of a single 1,200-mg intravenous dose of oritavancin in normal healthy volunteers. Pooled plasma with oritavancin added ex vivo showed concentration-dependent prolongation of prothrombin time/international normalized ratio (PT/INR), activated partial thromboplastin time (aPTT), and dilute Russell viper venom time (DRVVT) test results. In contrast, oritavancin had no effect on the activated protein C resistance assay, chromogenic anti-factor Xa assay (anti-FXa), thrombin time, and an immunoassay for the laboratory diagnosis of heparin-induced thrombocytopenia. In participants that received a single dose of oritavancin, elevations in PT/INR result, aPTT, DRVVT, activated clotting time, and silica clotting time occurred, with the maximum times to resolution of test interference determined to be 12, 120, 72, 24, and 18 h, respectively. The anti-FXa assay was unaffected, whereas transient elevations in D dimer levels were observed in 30% of participants, with a maximum time to resolution of 72 h. Although oritavancin has no impact on the coagulation system in vivo, a single dose of oritavancin can produce falsely elevated values of some coagulation tests used to monitor hemostasis. The interference of oritavancin on affected tests is transient, and the test results revert to normal ranges within specified times after dosing.


Asunto(s)
Antibacterianos/uso terapéutico , Coagulación Sanguínea/efectos de los fármacos , Glicopéptidos/uso terapéutico , Adulto , Pruebas de Coagulación Sanguínea , Femenino , Hemostasis/efectos de los fármacos , Humanos , Lipoglucopéptidos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Artículo en Inglés | MEDLINE | ID: mdl-28784674

RESUMEN

There are limited therapeutic options to treat infections caused by vancomycin-resistant Enterococcus faecium (VREfm). The lipoglycopeptide oritavancin exhibits in vitro activity against this pathogen, although its utility against infections caused by VREfm has not been clinically established. In this study, the pharmacodynamic activity of free-drug levels associated with 12 mg/kg/day of daptomycin and a single 1,200-mg dose of oritavancin were determined against three VanA VREfm isolates in an in vitro pharmacokinetic/pharmacodynamic model.


Asunto(s)
Antibacterianos/farmacología , Enterococcus faecium/efectos de los fármacos , Glicopéptidos/farmacología , Glicopéptidos/farmacocinética , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Antibacterianos/farmacocinética , Daptomicina/farmacocinética , Daptomicina/farmacología , Enterococcus faecium/aislamiento & purificación , Humanos , Lipoglucopéptidos , Pruebas de Sensibilidad Microbiana , Resistencia a la Vancomicina/fisiología , Enterococos Resistentes a la Vancomicina/aislamiento & purificación
16.
Biochim Biophys Acta ; 1848(1 Pt B): 350-62, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24915020

RESUMEN

Peptidoglycan is an essential component of cell wall in Gram-positive bacteria with unknown architecture. In this review, we summarize solid-state NMR approaches to address some of the unknowns in the Gram-positive bacteria peptidoglycan architecture: 1) peptidoglycan backbone conformation, 2) PG-lattice structure, 3) variations in the peptidoglycan architecture and composition, 4) the effects of peptidoglycan bridge-length on the peptidoglycan architecture in Fem mutants, 5) the orientation of glycan strands with respect to the membrane, and 6) the relationship between the peptidoglycan structure and the glycopeptide antibiotic mode of action. Solid-state NMR analyses of Staphylococcus aureus cell wall show that peptidoglycan chains are surprisingly ordered and densely packed. The peptidoglycan disaccharide backbone adopts 4-fold screw helical symmetry with the disaccharide unit periodicity of 40Å. Peptidoglycan lattice in the S. aureus cell wall is formed by cross-linked PG stems that have parallel orientations. The structural characterization of Fem-mutants of S. aureus with varying lengths of bridge structures suggests that the PG-bridge length is an important determining factor for the PG architecture.


Asunto(s)
Bacterias Grampositivas/química , Espectroscopía de Resonancia Magnética/métodos , Peptidoglicano/química , Antibacterianos/farmacología , Pared Celular/química , Conformación Molecular , Staphylococcus aureus/química
17.
Clin Infect Dis ; 61(4): 627-32, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25900171

RESUMEN

Oritavancin is a lipoglycopeptide antibiotic that has been shown to be effective for the treatment of acute bacterial skin and skin structure infections (ABSSSIs). This antibiotic has multiple mechanisms of action including inhibiting peptidoglycan cell wall synthesis and disrupting bacterial cell membrane, leading to cell death. Oritavancin is highly active against common gram-positive pathogens including methicillin-resistant Staphylococcus aureus, vancomycin-intermediate S. aureus, vancomycin-resistant S. aureus, and vancomycin-resistant enterococci. The drug is administered as a single intravenous dose of 1200 mg over 3 hours in adult patients, and because of its terminal half-life of 393 hours, repeat dosing is not required in the treatment of ABSSIs. There is a very slow elimination from tissue sites, and no dosing adjustments are required for renal or hepatic insufficiency. Two clinical trials have demonstrated noninferiority compared with vancomycin in the treatment of ABSSSIs. Other than liver enzyme elevation and the occurrence of osteomyelitis, oritavancin has been associated with adverse events similar to those of vancomycin in follow-up for up to 60 days. Patients should be monitored for osteomyelitis and alternate therapy given in the case of confirmed or suspected osteomyelitis. Although oritavancin is an attractive antibiotic to consider in the outpatient area, its efficacy and safety in the treatment of other sites of infection are yet to be established.


Asunto(s)
Antibacterianos/farmacología , Antibacterianos/farmacocinética , Glicopéptidos/farmacología , Glicopéptidos/farmacocinética , Administración Intravenosa , Antibacterianos/uso terapéutico , Ensayos Clínicos como Asunto , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Enzimas/sangre , Glicopéptidos/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Semivida , Humanos , Lipoglucopéptidos , Hígado/efectos de los fármacos , Hígado/enzimología , Osteomielitis/inducido químicamente , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Infecciones de los Tejidos Blandos/tratamiento farmacológico
18.
Clin Infect Dis ; 60(2): 254-62, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25294250

RESUMEN

BACKGROUND: Oritavancin is a lipoglycopeptide antibiotic with rapid bactericidal activity against gram-positive bacteria. Its concentration-dependent activity and long half-life allow for single-dose treatment. METHODS: In a randomized, double-blind trial, adults with acute bacterial skin and skin structure infections (ABSSSIs) received either a single intravenous 1200-mg dose of oritavancin or 7-10 days of twice-daily vancomycin. Three efficacy endpoints were tested for noninferiority: (1) primary composite endpoint at 48-72 hours (cessation of spreading or reduction in lesion size, absence of fever, and no rescue antibiotic); (2) investigator-assessed clinical cure 7-14 days after end of treatment; and (3) ≥20% reduction in lesion area at 48-72 hours. RESULTS: A total of 503 and 502 patients comprised the modified intent-to-treat population for oritavancin and vancomycin, respectively. All 3 efficacy endpoints met the 10% noninferiority margin: the primary composite endpoint (80.1% vs 82.9%; 95% confidence interval [CI], -7.5 to 2.0), investigator-assessed clinical cure (82.7% vs 80.5%; 95% CI, -2.6 to 7.0), and proportion of patients attaining ≥20% reduction in lesion area (85.9% vs 85.3%; 95% CI, -3.7 to 5.0) for oritavancin vs vancomycin, respectively. Efficacy outcomes by pathogen, including methicillin-resistant Staphylococcus aureus and the frequency of adverse events, were similar between treatment groups. CONCLUSIONS: A single 1200-mg dose of oritavancin was noninferior to 7-10 days of vancomycin in treating ABSSSIs caused by gram-positive pathogens, and was well tolerated. Oritavancin provides a single-dose alternative to multidose therapies for the treatment of ABSSSIs. Clinical Trials Registration. NCT01252732.


Asunto(s)
Antibacterianos/uso terapéutico , Glicopéptidos/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Vancomicina/uso terapéutico , Administración Intravenosa , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Infecciones por Bacterias Grampositivas/patología , Humanos , Lipoglucopéptidos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
19.
Infect Dis Ther ; 13(3): 535-547, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38421519

RESUMEN

INTRODUCTION: Weekly intravenous (IV) oritavancin and daily daptomycin were compared in an outpatient setting following extensive surgical debridement for treating patients with osteomyelitis. METHODS: This was a retrospective, observational study of patients diagnosed with acute osteomyelitis. Exclusion criteria were the use of Gram-negative antibiotic therapy, use of antibiotics for more than 48 h prior to oritavancin or daptomycin or prior use of > 2 doses of oritavancin or more than 4 weeks of daptomycin. Clinical success was resolution or improvement of symptoms and no further treatment. Data were analyzed with Chi-square test or Fisher's exact test. RESULTS: Consecutive outpatients (n = 150) with acute osteomyelitis who were treated with oritavancin or daptomycin (1:1) following extensive surgical debridement were identified. Staphylococcus aureus was the most common pathogen (n = 117). No patient in either group received prior antibiotic therapy (previous 30 days) or was hospitalized within 90 days prior to surgical debridement. Twenty-one (28%) patients prescribed oritavancin had chronic kidney disease, seven of whom were receiving hemodialysis or peritoneal dialysis. Compared to oritavancin, patients prescribed daptomycin had higher rates of all-cause readmission [odds ratio (OR) 2.89; p < 0.001], more infection-related readmission (OR 3.19; p < 0.001), and greater likelihood of receiving antibiotics post-discontinuation of initial therapy (OR 2.13; p < 0.001). Repeat surgical debridement was required for 68.0% with daptomycin vs. 23.1% with oritavancin (p < 0.001). CONCLUSIONS: Oritavancin demonstrated a significantly higher rate of clinical success compared to daptomycin, with lower all-cause and infection-related readmissions, reduced need for repeat surgical debridement, and fewer additional antibiotic requirements.

20.
Pathogens ; 13(3)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38535533

RESUMEN

Long-acting lipoglycopeptides (LGPs), such as dalbavancin and oritavancin, are semisynthetic antibiotics known for their strong effectiveness against a wide array of Gram-positive bacteria. This includes Staphylococcus aureus, both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) strains, coagulase-negative Staphylococci (CoNS), streptococci, and vancomycin-sensitive Enterococcus faecalis. A literature search was conducted on PubMed and on ClinicalTrials.gov to identify articles published until July 2023 investigating the use of oritavancin and dalbavancin in clinical practice. The review included case reports, case series, observational studies, and clinical studies. Although more consistent data are needed, LGPs seem to be a good alternative that may provide a quicker hospital discharge and reduce long-term intravenous access and therapy. This is attributed to their unique pharmacologic and pharmacokinetic characteristics. More quality data (i.e., number of patients treated with clinical success) are needed before clinicians may use these therapies more widely.

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