ppi-0903 and Cystic-Fibrosis

Acute pulmonary exacerbations (APE) are a complication of cystic fibrosis (CF) and are associated with morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA) is one of many organisms that has been detected in the airways of patients with CF. This review provides an evidence-based summary of pharmacokinetic/pharmacodynamic (PK/PD), tolerability, and efficacy studies utilizing anti-MRSA antibiotics (ie, ceftaroline, clindamycin, fluoroquinolone derivatives (ciprofloxacin, levofloxacin), glycopeptide derivatives (telavancin, vancomycin), linezolid, rifampin, sulfamethoxazole/trimethoprim (SMZ/TMP), and tetracycline derivatives (doxycycline, minocycline, tigecycline) in the treatment of APE and identifies areas where further study is warranted. A recent utilization study of antimicrobials for anti-MRSA has shown some CF Foundation accredited care centers and affiliate programs are using doses higher than the FDA-approved doses. Further studies are needed to determine the PK/PD properties in CF patients with clindamycin, minocycline, rifampin, SMZ/TMP, telavancin, and tigecycline; as well as, efficacy and tolerability studies with ciprofloxacin, clindamycin, doxycycline, levofloxacin, minocycline, rifampin, SMZ/TMP, in CF patients with MRSA.

Topics: Aminoglycosides; Anti-Bacterial Agents; Ceftaroline; Cephalosporins; Ciprofloxacin; Clindamycin; Cystic Fibrosis; Humans; Linezolid; Lipoglycopeptides; Methicillin; Methicillin-Resistant Staphylococcus aureus; Rifampin; Trimethoprim, Sulfamethoxazole Drug Combination; Vancomycin

To evaluate the pharmacokinetics and pharmacodynamics of ceftaroline in adults with cystic fibrosis (CF).. Open-label, single-center, prospective study.. University-affiliated teaching institution.. Eight patients with a diagnosis of CF and a history of methicillin-resistant Staphylococcus aureus who were treated with ceftaroline between November 2013 and September 2014.. All patients received at least three doses of intravenous ceftaroline 600 mg every 12 hours, administered as a 60-minute infusion, to achieve steady-state concentrations before blood sample collection. After an interim analysis of the first four patients' pharmacokinetic data, the remaining four patients received a change in dosage of ceftaroline to 600 mg every 8 hours.. Patients' blood samples were collected at two time points, 2 and 6 hours after infusion initiation, after administration of at least three doses of ceftaroline. Serum ceftaroline concentrations were determined by using a validated mass spectrometry, with a lower limit of detection of 20 ng/ml. These ceftaroline concentrations were used to estimate patient-specific pharmacokinetic parameters, and 10,000-patient Monte Carlo simulations were performed to determine the pharmacodynamic probability of target attainment (PTA) for ceftaroline in adults with CF. A PTA of 90% or higher for the desired pharmacodynamic target was considered adequate. The PTA for 60% or higher of the dosing interval during which free (unbound) drug concentrations exceed the minimum inhibitory concentration (%fT > MIC) was simulated for various MICs. Compared with values previously reported in other populations, the volume of distribution was increased in the study patients, and the estimated half-life was shorter. Monte Carlo simulations revealed that a dose of ceftaroline 600 mg every 8 hours, infused over 60 minutes, maintained a higher than 90% PTA for %fT > MIC of 60% or higher for an MIC at the susceptibility breakpoint of 1 mg/L.. The pharmacokinetics of ceftaroline is altered in adults with CF, which suggests the need for modified dosing in this patient population to achieve adequate %fT > MIC. A dosage of intravenous ceftaroline 600 mg every 8 hours administered as a 60-minute infusion should be considered to achieve 60% fT > MIC.

Topics: Adult; Anti-Bacterial Agents; Ceftaroline; Cephalosporins; Cystic Fibrosis; Drug Administration Schedule; Female; Humans; Infusions, Intravenous; Male; Microbial Sensitivity Tests; Middle Aged; Prospective Studies; Young Adult

Vancomycin remains a first-line treatment for methicillin-resistant Staphylococcus aureus (MRSA)-mediated acute pulmonary exacerbations (APEs) in adult cystic fibrosis (CF) patients; however, optimal alternatives remain poorly defined. The aim of this study was to determine the safety and efficacy of ceftaroline for MRSA-mediated APEs of CF in adults.. We conducted a retrospective, observational cohort study comparing ceftaroline with vancomycin for the treatment of MRSA-mediated APEs in adult CF patients. The primary endpoint was the return to at least 90% of baseline lung function measured by discharge FEV. A total of 55 patients were included in the analysis (22 receiving ceftaroline and 33 receiving vancomycin). Of the patients included in the analysis, 13 patients (59%) in the ceftaroline group and 24 patients (73%) in the vancomycin group met the primary outcome (P = 0.38). FEV. Our small cohort study supports ceftaroline as an alternative treatment option for MRSA-mediated APE of CF in adults.

Topics: Adult; Anti-Bacterial Agents; Ceftaroline; Cephalosporins; Cohort Studies; Cystic Fibrosis; Humans; Lung; Methicillin-Resistant Staphylococcus aureus; Retrospective Studies; Staphylococcal Infections; Vancomycin

Respiratory infection with methicillin-resistant Staphylococcus aureus (MRSA) is an increasing complication in cystic fibrosis (CF) that results in accelerated lung function decline and mortality. Vancomycin is considered a first-line intravenous treatment agent for MRSA associated acute pulmonary exacerbations (APEs); however, rates of vancomycin intolerance and resistance have been observed. These factors have led to the exploration of additional treatment options for treating MRSA associated APEs.. This is a retrospective chart review conducted at a CF center including patients 0 to 21 years of age with CF admitted for an APE and treated with either vancomycin or ceftaroline between January 2016 and August 2018. The primary endpoint was to determine ceftaroline efficacy compared to vancomycin in the treatment of MRSA associated APEs.. There were 180 patients included in the study with 90 patients in each antibiotic group. Admission to discharge forced expiratory volume in 1 second (FEV. In this retrospective study, no difference existed between ceftaroline and vancomycin with regard to observed improvement in lung function from admission to discharge. Additionally, no difference was observed in mean FEV

Topics: Administration, Intravenous; Adolescent; Adult; Anti-Bacterial Agents; Ceftaroline; Cephalosporins; Child; Child, Preschool; Cystic Fibrosis; Female; Forced Expiratory Volume; Humans; Infant; Infant, Newborn; Male; Methicillin-Resistant Staphylococcus aureus; Retrospective Studies; Staphylococcal Infections; Vancomycin; Young Adult

Chronic airways infection with methicillin-resistant Staphylococcus aureus (MRSA) is associated with worse respiratory disease cystic fibrosis (CF) patients. Ceftaroline is a cephalosporin that inhibits the penicillin-binding protein (PBP2a) uniquely produced by MRSA. We analyzed 335 S. aureus isolates from CF sputum samples collected at three US centers between 2015-2018. Molecular relationships demonstrated that high-level resistance of preceding isolates to carbapenems were associated with subsequent isolation of ceftaroline resistant CF MRSA. In vitro evolution experiments showed that pre-exposure of CF MRSA to meropenem with further selection with ceftaroline implied mutations in mecA and additional mutations in pbp1 and pbp2, targets of carbapenems; no effects were achieved by other β-lactams. An in vivo pneumonia mouse model showed the potential therapeutic efficacy of ceftaroline/meropenem combination against ceftaroline-resistant CF MRSA infections. Thus, the present findings highlight risk factors and potential therapeutic strategies offering an opportunity to both prevent and address antibiotic resistance in this patient population.

Topics: Anti-Bacterial Agents; Bacterial Proteins; Carbapenems; Ceftaroline; Cephalosporins; Cystic Fibrosis; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Genome, Bacterial; Humans; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Mutation; Staphylococcal Infections

Methicillin-resistant Staphylococcus aureus (MRSA) is a prevalent pathogen in patients with cystic fibrosis (CF) associated with increased morbidity. Ceftaroline fosamil is an intravenous (IV) cephalosporin with activity against MRSA. There are minimal data regarding dosing in the CF population. The objective of this study was to determine the pharmacokinetic and pharmacodynamic profile of IV ceftaroline in patients with CF.. We conducted a single-center prospective study of children and young adults with CF receiving ceftaroline (15mg/kg IV up to 600mg every 8h) as part of treatment for a CF pulmonary exacerbation between June 2016 and April 2017. Seven patients were enrolled for a total of 10 treatment courses. For each treatment course, up to 8 plasma samples were assayed for ceftaroline using ultra-high performance liquid chromatography with mass spectrometry. Maximum plasma concentration, systemic clearance, and elimination half-life were calculated. The area under the curve (AUC) above the minimum inhibitory concentration (MIC) and the percent time above the MIC (%fT>MIC) were determined for each subject using MICs of 0.5, 1, and 2μg/mL and the measured MIC if available.. The mean (SD) age for the 7 patients was 20.3 (8.0) years. Mean (SD) maximum plasma concentration of ceftaroline was 22.7 (9.6) μg/mL, systemic clearance 7.9 (3.3) L/h, and half-life 1.1 (0.4) hours. Using a MIC of 1 μg/mL, accepted as the MIC 90 of MRSA isolates, AUC above MIC mean (SD) was 53.6 (19.5) μg·h/mL, mean (SD) %fT>MIC was 75.7 (10.4), and all subjects had >60%fT>MIC.. In this cohort of CF patients, mean ceftaroline half-life was 1.1h, which is notably lower than the general population. The dosing regimen studied, which exceeds the recommended dosing in the non-CF population, was adequate to achieve >60% time above the MIC in all patients.

Topics: Adolescent; Adult; Anti-Bacterial Agents; Ceftaroline; Cephalosporins; Child; Chromatography, Liquid; Cystic Fibrosis; Dose-Response Relationship, Drug; Drug Monitoring; Female; Half-Life; Humans; Male; Mass Spectrometry; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Prospective Studies; Treatment Outcome

Ceftaroline is the first member of a novel class of cephalosporins approved for use in the United States. Although prior studies have identified eight ceftaroline-resistant methicillin-resistant Staphylococcus aureus (MRSA) isolates in Europe and Asia with MICs ranging from 4 to 8 mg/liter, high-level resistance to ceftaroline (>32 mg/liter) has not been described in MRSA strains isolated in the United States. We isolated a ceftaroline-resistant (MIC > 32 mg/liter) MRSA strain from the blood of a cystic fibrosis patient and five MRSA strains from the respiratory tract of this patient. Whole-genome sequencing identified two amino acid-altering mutations uniquely present in the ceftaroline-binding pocket of the transpeptidase region of penicillin-binding protein 2a (PBP2a) in ceftaroline-resistant isolates. Biochemical analyses and the study of isogenic mutant strains confirmed that these changes caused ceftaroline resistance. Thus, we identified the molecular mechanism of ceftaroline resistance in the first MRSA strain with high-level ceftaroline resistance isolated in the United States.

Topics: Adult; Amino Acid Substitution; Anti-Bacterial Agents; Base Sequence; Binding Sites; Ceftaroline; Cephalosporins; Cystic Fibrosis; DNA, Bacterial; Drug Resistance, Bacterial; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; MutS DNA Mismatch-Binding Protein; Penicillin-Binding Proteins; Sequence Analysis, DNA; Staphylococcal Infections; Young Adult