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Roberta S. Hare

Bio: Roberta S. Hare is an academic researcher from Schering-Plough. The author has contributed to research in topics: Posaconazole & Antibacterial agent. The author has an hindex of 29, co-authored 67 publications receiving 4543 citations.


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Journal ArticleDOI
TL;DR: A preliminary assessment of the amino acids which may be important in binding aminoglycosides was obtained from data and from the results of mutational analysis of several of the genes encoding am inoglycoside-modifying enzymes.

1,096 citations

Journal ArticleDOI
TL;DR: Posaconazole exhibited potent antifungal activity against a wide variety of clinically important fungal pathogens and was frequently more active than other azoles and amphotericin B.
Abstract: The in vitro activity of the novel triazole antifungal agent posaconazole (Noxafil; SCH 56592) was assessed in 45 laboratories against approximately 19,000 clinically important strains of yeasts and molds. The activity of posaconazole was compared with those of itraconazole, fluconazole, voriconazole, and amphotericin B against subsets of the isolates. Strains were tested utilizing Clinical and Laboratory Standards Institute broth microdilution methods using RPMI 1640 medium (except for amphotericin B, which was frequently tested in antibiotic medium 3). MICs were determined at the recommended endpoints and time intervals. Against all fungi in the database (22,850 MICs), the MIC(50) and MIC(90) values for posaconazole were 0.063 microg/ml and 1 mug/ml, respectively. MIC(90) values against all yeasts (18,351 MICs) and molds (4,499 MICs) were both 1 mug/ml. In comparative studies against subsets of the isolates, posaconazole was more active than, or within 1 dilution of, the comparator drugs itraconazole, fluconazole, voriconazole, and amphotericin B against approximately 7,000 isolates of Candida and Cryptococcus spp. Against all molds (1,702 MICs, including 1,423 MICs for Aspergillus isolates), posaconazole was more active than or equal to the comparator drugs in almost every category. Posaconazole was active against isolates of Candida and Aspergillus spp. that exhibit resistance to fluconazole, voriconazole, and amphotericin B and was much more active than the other triazoles against zygomycetes. Posaconazole exhibited potent antifungal activity against a wide variety of clinically important fungal pathogens and was frequently more active than other azoles and amphotericin B.

460 citations

Journal ArticleDOI
TL;DR: The results identify which MDR pumps contribute to intrinsic resistance under the conditions tested and supply practical information useful for designing sensitive assay strains for cell-based screening of antibacterial compounds.
Abstract: The contribution of seven known and nine predicted genes or operons associated with multidrug resistance to the susceptibility of Escherichia coli W3110 was assessed for 20 different classes of antimicrobial compounds that include antibiotics, antiseptics, detergents, and dyes. Strains were constructed with deletions for genes in the major facilitator superfamily, the resistance nodulation-cell division family, the small multidrug resistance family, the ATP-binding cassette family, and outer membrane factors. The agar dilution MICs of 35 compounds were determined for strains with deletions for multidrug resistance (MDR) pumps. Deletions in acrAB or tolC resulted in increased susceptibilities to the majority of compounds tested. The remaining MDR pump gene deletions resulted in increased susceptibilities to far fewer compounds. The results identify which MDR pumps contribute to intrinsic resistance under the conditions tested and supply practical information useful for designing sensitive assay strains for cell-based screening of antibacterial compounds.

458 citations

Journal ArticleDOI
TL;DR: It is the thesis of this paper that rational dose-selection decisions can be made on the basis of the pharmacodynamics (PDs) of the test agent predicted by a mathematical model, and drug exposure or the ratio of the area under the concentration-time curve/MIC (AUC/MIC) was found to be the best predictor of microbiological efficacy.
Abstract: One of the most challenging issues in the design of phase II/III clinical trials of antimicrobial agents is dose selection. The choice is often based on preclinical data from pharmacokinetic (PK) studies with animals and healthy volunteers but is rarely linked directly to the target organisms except by the MIC, an in vitro measure of antimicrobial activity with many limitations. It is the thesis of this paper that rational dose-selection decisions can be made on the basis of the pharmacodynamics (PDs) of the test agent predicted by a mathematical model which uses four data sets: (i) the distribution of MICs for clinical isolates, (ii) the distribution of the values of the PK parameters for the test drug in the population, (iii) the PD target(s) developed from animal models of infection, and (iv) the protein binding characteristics of the test drug. In performing this study with the new anti-infective agent evernimicin, we collected a large number (n = 4,543) of recent clinical isolates of gram-positive pathogens (Streptococcus pneumoniae, Enterococcus faecalis and Enterococcus faecium, and Staphylococcus aureus) and determined the MICs using E-test methods (AB Biodisk, Stockholm, Sweden) for susceptibility to evernimicin. Population PK data were collected from healthy volunteers (n = 40) and patients with hypoalbuminemia (n = 12), and the data were analyzed by using NPEM III. PD targets were developed with a neutropenic murine thigh infection model with three target pathogens: S. pneumoniae (n = 5), E. faecalis (n = 2), and S. aureus (n = 4). Drug exposure or the ratio of the area under the concentration-time curve/MIC (AUC/MIC) was found to be the best predictor of microbiological efficacy. There were three possible microbiological results: stasis of the initial inoculum at 24 h (107 CFU), log killing (pathogen dependent, ranging from 1 to 3 log10), or 90% maximal killing effect (90% Emax). The levels of protein binding in humans and mice were similar. The PK and PD of 6 and 9 mg of evernimicin per kg of body weight were compared; the population values for the model parameters and population covariance matrix were used to generate five Monte Carlo simulations with 200 subjects each. The fractional probability of attaining the three PD targets was calculated for each dose and for each of the three pathogens. All differences in the fractional probability of attaining the target AUC/MIC in this PD model were significant. For S. pneumoniae, the probability of attaining all three PD targets was high for both doses. For S. aureus and enterococci, there were increasing differences between the 6- and 9-mg/kg evernimicin doses for reaching the 2 log killing (S. aureus), 1 log killing (enterococci), or 90% Emax AUC/MIC targets. This same approach may also be used to set preliminary in vitro MIC breakpoints.

231 citations

Journal ArticleDOI
TL;DR: The data suggest that posaconazole, as an oral medication, has clinical activity against fungal infections of the CNS and may provide a valuable alternative to parenteral therapy in patients failing existing antifungal agents.
Abstract: Objectives: A multinational, multicentre, open-label clinical trial was conducted to evaluate the safety and efficacyof posaconazole,anextended-spectrum triazole antifungalagent,in subjects withinvasive fungal infections who had refractory disease or who were intolerant of standard antifungal therapy. In this subanalysis, we report on those subjects in this trial who had a fungal infection that involved the CNS. Methods: Subjects received posaconazole oral suspension 800 mg/day in divided doses for up to 1 year; however,subjectscouldreceiveadditionaltherapyaspartofatreatment-useextensionprotocol.Ablinded, third-party data review committee determined subject eligibility and outcome. Results: Of the 330 subjects who enrolled in the study, 53 had infections of the CNS, of which 39 were consideredevaluableforefficacy.Mosthadrefractorydisease(37of39)andunderlyingHIVinfection(29of 39). Twenty-nine subjects had cryptococcal infections, and 10 had infections caused by other fungal pathogens[Aspergillusspp.(four),Pseudallescheriaboydii(two),Coccidioidesimmitis(one),Histoplasma capsulatum(one),Ramichloridiummackenziei(one),andApophysomyceselegansplusaBasidiomycetes sp. (one)]. Successful outcomes were observed in 14 of 29 (48%) subjects with cryptococcal meningitis and five of 10 (50%) subjects with CNS infections due to other fungal pathogens. Posaconazole was well tolerated. Conclusions: These data suggest that posaconazole, as an oral medication, has clinical activity against fungal infections of the CNS andmay provide a valuablealternative to parenteral therapy in patients failing existing antifungal agents.

209 citations


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Journal ArticleDOI
TL;DR: A web server providing a convenient way of identifying acquired antimicrobial resistance genes in completely sequenced isolates was created, and the method was evaluated on WGS chromosomes and plasmids of 30 isolates.
Abstract: Objectives Identification of antimicrobial resistance genes is important for understanding the underlying mechanisms and the epidemiology of antimicrobial resistance. As the costs of whole-genome sequencing (WGS) continue to decline, it becomes increasingly available in routine diagnostic laboratories and is anticipated to substitute traditional methods for resistance gene identification. Thus, the current challenge is to extract the relevant information from the large amount of generated data.

3,956 citations

Journal ArticleDOI
TL;DR: Introduced to the Market in the Last Decade (2001−2011) Jiang Wang,† María Sańchez-Rosello,́‡,§ Jose ́ Luis Aceña, Carlos del Pozo,‡ and Hong Liu.
Abstract: Introduced to the Market in the Last Decade (2001−2011) Jiang Wang,† María Sańchez-Rosello,́‡,§ Jose ́ Luis Aceña, Carlos del Pozo,‡ Alexander E. Sorochinsky, Santos Fustero,*,‡,§ Vadim A. Soloshonok,* and Hong Liu*,† †Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China ‡Department of Organic Chemistry, Faculty of Pharmacy, University of Valencia, Av. Vicente Andreś Estelleś, 46100 Burjassot, Valencia, Spain Laboratorio de Molećulas Orgańicas, Centro de Investigacioń Príncipe Felipe, C/ Eduardo Primo Yuf́era 3, 46012 Valencia, Spain Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizab́al 3, 20018 San Sebastian, Spain IKERBASQUE, Basque Foundation for Science, Alameda Urquijo, 36-5 Plaza Bizkaia, 48011 Bilbao, Spain Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Murmanska Street 1, 02660 Kyiv-94, Ukraine

3,368 citations

Journal ArticleDOI
TL;DR: These updated guidelines replace the previous guidelines published in the 15 January 2004 issue of Clinical Infectious Diseases and are intended for use by health care providers who care for patients who either have or are at risk of these infections.
Abstract: Guidelines for the management of patients with invasive candidiasis and mucosal candidiasis were prepared by an Expert Panel of the Infectious Diseases Society of America. These updated guidelines replace the previous guidelines published in the 15 January 2004 issue of Clinical Infectious Diseases and are intended for use by health care providers who care for patients who either have or are at risk of these infections. Since 2004, several new antifungal agents have become available, and several new studies have been published relating to the treatment of candidemia, other forms of invasive candidiasis, and mucosal disease, including oropharyngeal and esophageal candidiasis. There are also recent prospective data on the prevention of invasive candidiasis in high-risk neonates and adults and on the empiric treatment of suspected invasive candidiasis in adults. This new information is incorporated into this revised document.

3,016 citations

Journal ArticleDOI
TL;DR: This research presents a novel, scalable, scalable and scalable approach that allows for real-time evaluation of the impact of Epstein-Barr virus on the development and management of childhood cancer in rats.
Abstract: Aspergillus species have emerged as an important cause of life-threatening infections in immunocompromised patients. This expanding population is composed of patients with prolonged neutropenia, advanced HIV infection, and inherited immunodeficiency and patients who have undergone allogeneic hematopoietic stem cell transplantation (HSCT) and/or lung transplantation. This document constitutes the guidelines of the Infectious Diseases Society of America for treatment of aspergillosis and replaces the practice guidelines for Aspergillus published in 2000 [1]. The objective of these guidelines is to summarize the current evidence for treatment of different forms of aspergillosis. The quality of evidence for treatment is scored according to a standard system used in other Infectious Diseases Society of America guidelines. This document reviews guidelines for management of the 3 major forms of aspergillosis: invasive aspergillosis, chronic (and saprophytic) forms of aspergillosis, and allergic forms of aspergillosis. Given the public health importance of invasive aspergillosis, emphasis is placed on the diagnosis, treatment, and prevention of the different forms of invasive aspergillosis, including invasive pulmonary aspergillosis, sinus aspergillosis, disseminated aspergillosis, and several types of single-organ invasive aspergillosis. There are few randomized trials on the treatment of invasive aspergillosis. The largest randomized controlled trial demonstrates that voriconazole is superior to deoxycholate amphotericin B (D-AMB) as primary treatment for invasive aspergillosis. Voriconazole is recommended for the primary treatment of invasive aspergillosis in most patients (A-I). Although invasive pulmonary aspergillosis accounts for the preponderance of cases treated with voriconazole, voriconazole has been used in enough cases of extrapulmonary and disseminated infection to allow one to infer that voriconazole is effective in these cases. A randomized trial comparing 2 doses of liposomal amphotericin B (L-AMB) showed similar efficacy in both arms, suggesting that liposomal therapy could be considered as alternative primary therapy in some patients (A-I). For salvage therapy, agents include lipid formulations of amphotericin (LFAB; A-II), posaconazole (B-II), itraconazole (B-II), caspofungin (B-II), or micafungin (B-II). Salvage therapy for invasive aspergillosis poses important challenges with significant gaps in knowledge. In patients whose aspergillosis is refractory to voriconazole, a paucity of data exist to guide management. Therapeutic options include a change of class using an amphotericin B (AMB) formulation or an echinocandin, such as caspofungin (B-II); further use of azoles should take into account host factors and pharmacokinetic considerations. Refractory infection may respond to a change to another drug class (B-II) or to a combination of agents (B-II). The role of combination therapy in the treatment of invasive aspergillosis as primary or salvage therapy is uncertain and warrants a prospective, controlled clinical trial. Assessment of patients with refractory aspergillosis may be difficult. In evaluating such patients, the diagnosis of invasive aspergillosis should be established if it was previously uncertain and should be confirmed if it was previously known. The drug dosage should be considered. Management options include a change to intravenous (IV) therapy, therapeutic monitoring of drug levels, change of drug class, and/or combination therapy. Antifungal prophylaxis with posaconazole can be recommended in the subgroup of HSCT recipients with graft-versus-host disease (GVHD) who are at high risk for invasive aspergillosis and in neutropenic patients with acute myelogenous leukemia or myelodysplastic syndrome who are at high risk for invasive aspergillosis (A-I). Management of breakthrough invasive aspergillosis in the context of mould-active azole prophylaxis is not defined by clinical trial data. The approach to such patients should be individualized on the basis of clinical criteria, including host immunosuppression, underlying disease, and site of infection, as well as consideration of antifungal dosing, therapeutic monitoring of drug levels, a switch to IV therapy, and/or a switch to another drug class (B-III). Certain conditions of invasive aspergillosis warrant consideration for surgical resection of the infected focus. These include but are not limited to pulmonary lesions contiguous with the heart or great vessels, invasion of the chest wall, osteomyelitis, pericardial infection, and endocarditis (B-III). Restoration of impaired host defenses is critical for improved outcome of invasive aspergillosis (A-III). Recovery from neutropenia in a persistently neutropenic host or reduction of corticosteroids in a patient receiving high-dose glucocorticosteroids is paramount for improved outcome in invasive aspergillosis. A special consideration is made concerning recommendations for therapy of aspergillosis in uncommon sites, such as osteomyelitis and endocarditis. There are very limited data on these infections, and most involve D-AMB as primary therapy simply because of its long-standing availability. Based on the strength of the randomized study, the panel recommends voriconazole for primary treatment of these very uncommon manifestations of invasive aspergillosis (B-III). Management of the chronic or saprophytic forms of aspergillosis varies depending on the condition. Single pulmonary aspergillomas may be best managed by surgical resection (B-III), whereas chronic cavitary and chronic necrotizing pulmonary aspergillosis require long-term medical therapy (B-III). The management of allergic forms of aspergillosis involves a combination of medical and anti-inflammatory therapy. For example, management of allergic bronchopulmonary aspergillosis (ABPA) involves the administration of itraconazole and corticosteroids (A-I). © 2008 by the Infectious Diseases Society of America. All rights reserved.

2,463 citations

Journal ArticleDOI
TL;DR: IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.
Abstract: It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

2,367 citations