Objectives: STM-001, a retargeted glycopeptide, is active against MDR E. coli expressing ESBLs including carbapenemases. Herein, we assessed its capability to combat E.
View Article and Find Full Text PDFThe ability of vancomycin-arginine (V-r) to extend the spectrum of activity of glycopeptides to Gram-negative bacteria was investigated. Its MIC towards , including β-lactamase expressing Ambler classes A, B, and D, was 8 to 16 μg/ml. Addition of 8 times the MIC of V-r to was acutely bactericidal and associated with a low frequency of resistance (<2.
View Article and Find Full Text PDFThe diazabicyclooctanes (DBOs) are a class of serine β-lactamase (SBL) inhibitors that use a strained urea moiety as the warhead to react with the active serine residue in the active site of SBLs. The first in-class drug, avibactam, as well as several other recently approved DBOs (e.g.
View Article and Find Full Text PDFCandida albicans is a major fungal pathogen of humans. It exists as a commensal in the oral cavity, gut or genital tract of most individuals, constrained by the local microbiota, epithelial barriers and immune defences. Their perturbation can lead to fungal outgrowth and the development of mucosal infections such as oropharyngeal or vulvovaginal candidiasis, and patients with compromised immunity are susceptible to life-threatening systemic infections.
View Article and Find Full Text PDFBackground: Increasing multidrug resistance rates in Neisseria gonorrhoeae have raised concerns and an urgent call for new antibiotics for treatment of gonorrhoea. Several decades of subdued drug development in this field and the recent failures of two new antibiotics to show non-inferiority compared with the current first-line antibiotics ceftriaxone plus azithromycin highlight the need for improved preclinical tools to predict clinical outcome of new drugs in the development process.
Objectives: To summarize current pharmacokinetic/pharmacodynamic (PK/PD) knowledge and dose-finding strategies for antibiotics against gonorrhoea.
The clinical effectiveness of the important β-lactam class of antibiotics is under threat by the emergence of resistance, mostly due to the production of acquired serine- (SBL) and metallo-β-lactamase (MBL) enzymes. To address this resistance issue, multiple β-lactam/β-lactamase inhibitor combinations have been successfully introduced into the clinic over the past several decades. However, all of those combinations contain SBL inhibitors and, as yet, there are no MBL inhibitors in clinical use.
View Article and Find Full Text PDFJ Antimicrob Chemother
October 2020
Background: During antifungal prophylaxis, micafungin is generally infused IV once daily over 1 h. In practice, less-frequent dosing could improve the quality of life in patients requiring long-term treatment or prophylaxis. The feasibility of this approach was assessed using humanized doses of daily or infrequent micafungin regimens.
View Article and Find Full Text PDFAspergillus spp. infections remain a global concern, with ∼30% attributable mortality of invasive aspergillosis (IA). VT-1598 is a novel fungal CYP51 inhibitor designed for exquisite selectivity versus human CYP enzymes to achieve a maximal therapeutic index and therefore maximal antifungal efficacy.
View Article and Find Full Text PDFAntimicrob Agents Chemother
March 2019
Murepavadin (POL7080) represents the first member of a novel class of outer membrane protein-targeting antibiotics. It specifically interacts with LptD and inhibits lipopolysaccharide (LPS) transport. Murepavadin is being developed for the treatment of serious infections by We determined the plasma protein binding and the pharmacokinetics of murepavadin in plasma and epithelial lining fluid (ELF; pulmonary) in infected animals, and we determined the exposure-response relationship.
View Article and Find Full Text PDFA defining pathophysiological hallmark of Alzheimer's disease (AD) is the amyloid plaque; an extracellular deposit of aggregated fibrillar Aβ peptides. Amyloid plaques are hard, brittle structures scattered throughout the hippocampus and cerebral cortex and are thought to cause hyperphosphorylation of tau, neurofibrillary tangles, and progressive neurodegeneration. Reactive astrocytes and microglia envelop the exterior of amyloid plaques and infiltrate their inner core.
View Article and Find Full Text PDFObjectives: In vitro and in vivo activity of the dihydroorotate dehydrogenase inhibitor olorofim (formerly F901318) (F2G Limited, UK) against clinically relevant species of the Aspergillus section Terrei was evaluated.
Methods: A total of 92 clinical Aspergillus section Terrei isolates [42 Aspergillus terreus sensu stricto and 50 cryptic species: Aspergillus alabamensis (n = 8), Aspergillus citrinoterreus (n = 27), Aspergillus floccosus (n = 1), Aspergillus hortai (n = 13) and Aspergillus neoafricanus (n = 1)] were evaluated. MICs were determined using the CLSI M38-A2 method.
Objectives: Annual global deaths from cryptococcal meningitis (CM) are estimated at 180 000 and mortality is as high as 30%, even with optimal therapy. VT-1598 is a novel fungal CYP51 inhibitor with potent intrinsic antifungal activity against Cryptococcus. We report here VT-1598's in vivo antifungal activity in a murine model of CM.
View Article and Find Full Text PDFInfections caused by carbapenem-resistant (CRE) are increasingly prevalent and have become a major worldwide threat to human health. Carbapenem resistance is driven primarily by the acquisition of β-lactamase enzymes, which are able to degrade carbapenem antibiotics (hence termed carbapenemases) and result in high levels of resistance and treatment failure. Clinically relevant carbapenemases include both serine β-lactamases (SBLs; e.
View Article and Find Full Text PDFAntimicrob Agents Chemother
August 2017
Novel approaches for the treatment of multidrug-resistant Gram-negative bacterial infections are urgently required. One approach is to potentiate the efficacy of existing antibiotics whose spectrum of activity is limited by the permeability barrier presented by the Gram-negative outer membrane. Cationic peptides derived from polymyxin B have been used to permeabilize the outer membrane, granting antibiotics that would otherwise be excluded access to their targets.
View Article and Find Full Text PDFObjectives: To investigate the efficacy of a potent novel antimicrobial protein of mass 6 kDa, epidermicin NI01, for eradicating the nasal burden of MRSA in a cotton rat ( Sigmodon hispidus ) model.
Methods: MRSA strain ATCC 43300 was used to establish a robust colonization of cotton rat nares. This model was used to evaluate the efficacy of topical 0.
Clostridium difficile causes infections of the colon in susceptible patients. Specifically, gut dysbiosis induced by treatment with broad-spectrum antibiotics facilitates germination of ingested C. difficile spores, expansion of vegetative cells, and production of symptom-causing toxins TcdA and TcdB.
View Article and Find Full Text PDFAntibiotics have saved countless lives and enabled the development of modern medicine over the past 70 years. However, it is clear that the success of antibiotics might only have been temporary and we now expect a long-term and perhaps never-ending challenge to find new therapies to combat antibiotic-resistant bacteria. A broader approach to address bacterial infection is needed.
View Article and Find Full Text PDFObjectives: SMT19969 is a novel antimicrobial under clinical development for the treatment of Clostridium difficile infection (CDI). The objective was to determine the comparative susceptibility of 82 C. difficile clinical isolates (which included ribotype 027 isolates and isolates with reduced metronidazole susceptibility) to SMT19969, fidaxomicin, vancomycin and metronidazole and to determine the killing kinetics and post-antibiotic effects of SMT19969, fidaxomicin and vancomycin against C.
View Article and Find Full Text PDFObjectives: SMT19969 is a novel narrow-spectrum antimicrobial under development for the treatment of Clostridium difficile infection (CDI). The objectives were to assess the relative efficacies of SMT19969, vancomycin and fidaxomicin in the hamster model of CDI.
Methods: Hamsters were infected with either C.
Background: In susceptible individuals, exposure to Aspergillus fumigatus can lead to the development of atopic lung diseases such as allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitization (SAFS). Protease allergens including Asp f 5 and Asp f 13 from Aspergillus fumigatus are thought to be important for initiation and progression of allergic asthma.
Objective: To assess the importance of secreted protease allergens Asp f 5 (matrix metalloprotease) and Asp f 13 (serine protease) in Aspergillus fumigatus-induced inflammation, airway hyperactivity, atopy and airway wall remodelling in a murine model following chronic exposure to secreted allergens.
Clin Vaccine Immunol
September 2014
Chronic biofilm infections are often accompanied by a chronic inflammatory response, leading to impaired healing and increased, irreversible damage to host tissues. Biofilm formation is a major virulence factor for Candida albicans and a challenge for treatment. Most current antifungals have proved ineffective in eradicating infections attributed to biofilms.
View Article and Find Full Text PDFObjective: Bacterial infection contributes to diverse noninfectious diseases and worsens outcome after stroke. Streptococcus pneumoniae, the most common infection in patients at risk of stroke, is a major cause of prolonged hospitalization and death of stroke patients, but how infection impacts clinical outcome is not known.
Methods: We induced sustained pulmonary infection by a human S.
Objectives: To evaluate the in vivo effectiveness of a combination treatment containing ranalexin (a natural antimicrobial peptide) and lysostaphin (an antistaphylococcal endopeptidase) for reducing nasal burden of methicillin-resistant Staphylococcus aureus (MRSA).
Methods: The community-acquired MRSA strain S. aureus NRS384 (USA300-0114) was used in the present study because it is commonly isolated from human nares and it established consistent and reproducible colonization of cotton rat nares.