RESUMO
OBJECTIVES: Lefamulin is a pleuromutilin antibiotic approved for the treatment of community-acquired bacterial pneumonia (CABP). Its spectrum of activity, good penetration into soft tissues and low rates of cross-resistance also make lefamulin a potentially valuable option for treatment of acute bacterial skin and skin structure infections (ABSSSIs). A Phase 2 trial of lefamulin for ABSSSI indicated similar efficacy of 100 and 150 mg q12h IV dosing regimens. In the present study, the potential of lefamulin for this indication was further evaluated from a translational pharmacokinetic/pharmacodynamic perspective. METHODS: PTA was determined for various dosages using Monte Carlo simulations of a population pharmacokinetic model of lefamulin in ABSSSI patients and preclinical exposure targets associated with bacteriostasis and a 1-log reduction in bacterial count. Overall target attainment against MSSA and MRSA was calculated using lefamulin MIC distributions. RESULTS: Overall attainment of the bacteriostasis target was 94% against MSSA and 84% against MRSA for the IV dosage approved for CABP (150 mg q12h). Using the same target, for the 100 mg q12h regimen, overall target attainment dropped to 68% against MSSA and 50% against MRSA. Using the 1-log reduction target, overall target attainment for both regimens was <40%. CONCLUSIONS: Lefamulin at the currently approved IV dosage covers most Staphylococcus aureus isolates when targeting drug exposure associated with bacteriostasis, suggesting potential of lefamulin for the treatment of ABSSSIs. Lefamulin may not be appropriate in ABSSSI when rapid bactericidal activity is warranted.
Assuntos
Infecções Comunitárias Adquiridas , Diterpenos , Pneumonia Bacteriana , Compostos Policíclicos , Dermatopatias Infecciosas , Tioglicolatos , Humanos , Pneumonia Bacteriana/tratamento farmacológico , Testes de Sensibilidade Microbiana , Bactérias , Antibacterianos/farmacologia , Dermatopatias Infecciosas/tratamento farmacológico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologiaRESUMO
BACKGROUND: Lefamulin, a first-in-class pleuromutilin antibiotic approved for intravenous and oral use in adults with community-acquired bacterial pneumonia (CABP), was noninferior to moxifloxacin in the Lefamulin Evaluation Against Pneumonia (LEAP) 1 intravenous-to-oral switch study and the LEAP 2 oral-only study. Using pooled LEAP 1/2 data, we examined lefamulin efficacy/safety overall and within subgroups of patients presenting with comorbidities typical in CABP management. METHODS: In LEAP 1, adults with CABP were randomized to receive intravenous lefamulin (150 mg every 12 h) for 5â7 days or moxifloxacin (400 mg every 24 h) for 7 days, with optional intravenous-to-oral switch if predefined improvement criteria were met. In LEAP 2, adults with CABP were randomized to receive oral lefamulin (600 mg every 12 h) for 5 days or moxifloxacin (400 mg every 24 h) for 7 days. Both studies assessed early clinical response (ECR) at 96 ± 24 h after first study drug dose and investigator assessment of clinical response (IACR) at test-of-cure (5â10 days after last dose). Pooled analyses of the overall population used a 10% noninferiority margin. RESULTS: Lefamulin (n = 646) was noninferior to moxifloxacin (n = 643) for ECR (89.3% vs 90.5%, respectively; difference - 1.1%; 95% CI - 4.4 to 2.2); IACR success rates at test-of-cure were similarly high (≥ 85.0%). High efficacy with both lefamulin and moxifloxacin was also demonstrated across all well-represented patient subgroups, including those with advanced age, diabetes mellitus, a history of cardiovascular diseases (e.g., hypertension, congestive heart failure, or arrhythmia) or chronic lung diseases (e.g., asthma or chronic obstructive pulmonary disease), elevated liver enzymes, or mild-to-moderate renal dysfunction. No new safety signals were identified. CONCLUSIONS: Lefamulin may provide a valuable intravenous/oral monotherapy alternative to fluoroquinolones or macrolides for empiric treatment of patients with CABP, including cases of patients at risk for poor outcomes due to age or various comorbidities. TRIAL REGISTRATION: ClinicalTrials.gov LEAP 1 (NCT02559310; Registration Date: 24/09/2015) and LEAP 2 (NCT02813694; Registration Date: 27/06/2016).
Assuntos
Antibacterianos/uso terapêutico , Diterpenos/administração & dosagem , Fluoroquinolonas/administração & dosagem , Moxifloxacina/administração & dosagem , Pneumonia Bacteriana/tratamento farmacológico , Compostos Policíclicos/administração & dosagem , Tioglicolatos/administração & dosagem , Administração Intravenosa , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Diterpenos/efeitos adversos , Método Duplo-Cego , Feminino , Fluoroquinolonas/efeitos adversos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Moxifloxacina/efeitos adversos , Compostos Policíclicos/efeitos adversos , Tioglicolatos/efeitos adversos , Estados Unidos , Adulto JovemRESUMO
Lefamulin is a novel pleuromutilin antibiotic with potent in vitro activity against key community-acquired bacterial pneumonia (CABP) pathogens. However, the clinical efficacy and safety of lefamulin for treating CABP remains unclear.An integrated analysis of 2 phase III trials investigating the clinical efficacy and safety of lefamulin vs moxifloxacin in the treatment of CABP was conducted.A total of 1289 patients (lefamulin group: 646 and moxifloxacin group: 643) were included in this analysis. The early clinical response rate was 89.3% and 90.5% among lefamulin and moxifloxacin group, respectively. Lefamulin was noninferior to moxifloxacin (89.3% vs 90.5%, RR: 0.99, 95% CI: 0.95-1.02, Iâ=â0%). In terms of clinical response at test of cure, no significant difference was observed between the lefamulin and moxifloxacin groups (for modified intention to treat population, RR: 0.98, 95% CI: 0.94-1.02, Iâ=â0%; for clinically evaluable population, RR: 0.96, 95% CI: 0.93-1.00, Iâ=â0%). In the subgroup analysis, the early clinical response rate at early clinical assessment and clinical response rate at test of cure of lefamulin was similar to that of moxifloxacin across different subgpopulations and all baseline CABP pathogens. Lefamulin was associated with a similar risk of adverse events as moxifloxacin.Clinical efficacy and tolerability for lefamulin in the treatment of CABP were similar to those for moxifloxacin.
Assuntos
Antibacterianos/uso terapêutico , Diterpenos/uso terapêutico , Moxifloxacina/uso terapêutico , Pneumonia Bacteriana/diagnóstico , Compostos Policíclicos/uso terapêutico , Tioglicolatos/uso terapêutico , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/mortalidade , Diterpenos/administração & dosagem , Diterpenos/farmacologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Moxifloxacina/administração & dosagem , Moxifloxacina/farmacologia , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/mortalidade , Compostos Policíclicos/administração & dosagem , Compostos Policíclicos/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , Taiwan , Tioglicolatos/administração & dosagem , Tioglicolatos/farmacologia , Resultado do TratamentoRESUMO
Lefamulin (BC-3781) is the first systemic pleuromutilin antibiotic found to be safe and effective in the treatment of community-acquired bacterial pneumonia (CABP) in humans. This novel antibiotic was developed to combat the increasing incidence of bacterial resistance to current therapies. As the first semisynthetic pleuromutilin for systemic use in humans, lefamulin has demonstrated efficacy against the most common bacteria responsible for CABP, including strains exhibiting resistance to macrolides, fluoroquinolones, tetracyclines, vancomycin, and beta-lactams. In vitro studies have demonstrated efficacy against Staphylococcus aureus, beta-hemolytic and viridans group streptococci, coagulase-negative staphylococci, Enterococcus faecium, Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophilia, and Moraxella catarrhalis at MIC values lower than those of currently available therapies. Two phase III trials (LEAP-1 and LEAP-2) have demonstrated similar findings, meeting non-inferiority criteria for CABP with a minimal side-effect profile. Pharmacokinetic and pharmacodynamic evaluations have shown sufficient drug levels in plasma, subcutaneous adipose tissue, skeletal muscle, and epithelial lining fluid, warranting further investigation for other clinical uses. Lefamulin was approved by the United States Food and Drug Administration (FDA) on 19 August 2019 for the treatment of CABP.
Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Diterpenos/farmacologia , Pneumonia Bacteriana/tratamento farmacológico , Compostos Policíclicos/farmacologia , Tioglicolatos/farmacologia , Antibacterianos/química , Diterpenos/química , Humanos , Testes de Sensibilidade Microbiana , Conformação Molecular , Pneumonia Bacteriana/microbiologia , Compostos Policíclicos/química , Tioglicolatos/químicaRESUMO
OBJECTIVES: Lefamulin is a semi-synthetic intravenous (iv) and oral pleuromutilin antibiotic active against community-acquired bacterial pneumonia (CABP) pathogens. Pharmacokinetic/pharmacodynamic (PK/PD) target attainment analyses were carried out to evaluate lefamulin 150 mg iv q12h and 600 mg orally q12h under fed and fasted conditions for the treatment of patients with CABP. METHODS: The analyses undertaken used a population PK model based on Phase 1 PK data, non-clinical PK/PD targets for efficacy and in vitro surveillance data for Streptococcus pneumoniae (SP) and Staphylococcus aureus (SA), and Monte Carlo simulation. Percentage probabilities of PK/PD target attainment by MIC on day 1 were determined using median total-drug epithelial lining fluid (ELF) and free-drug plasma AUC:MIC ratio targets associated with 1 and 2 log10 cfu reductions from baseline. RESULTS: Percentage probabilities of attaining the total-drug ELF AUC:MIC ratio target for a 1 log10 cfu reduction from baseline for SP were ≥99.2% at the MIC90 of 0.12 mg/L and 96.7%, 82.1% and 96.3% for iv and oral dosing regimens under fed and fasted conditions, respectively, at the MIC99 of 0.25 mg/L. Percentage probabilities of attaining the free-drug plasma AUC:MIC target for the same endpoint at the SP MIC99 were 100% for each regimen. For the SA MIC90 of 0.12 mg/L and AUC:MIC ratio targets for the same endpoint, percentage probabilities were 92.7%-100% for iv and oral dosing regimens. CONCLUSIONS: These data provide support for lefamulin 150 mg iv q12h and 600 mg orally q12h for the treatment of patients with CABP and suggest that doses may not need to be taken under fasted conditions.
Assuntos
Antibacterianos/farmacocinética , Bactérias/efeitos dos fármacos , Infecções Comunitárias Adquiridas/tratamento farmacológico , Simulação por Computador , Diterpenos/farmacocinética , Compostos Policíclicos/farmacocinética , Tioglicolatos/farmacocinética , Administração Intravenosa , Administração Oral , Antibacterianos/administração & dosagem , Diterpenos/administração & dosagem , Jejum , Humanos , Testes de Sensibilidade Microbiana , Modelos Estatísticos , Método de Monte Carlo , Pneumonia Bacteriana/tratamento farmacológico , Compostos Policíclicos/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Tioglicolatos/administração & dosagemRESUMO
OBJECTIVES: To characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of lefamulin in the neutropenic murine thigh infection model to ascertain (i) which PK/PD index best correlates with efficacy and (ii) whether the magnitude of the index that drives efficacy varies for different pathogens. METHODS: We evaluated the in vivo PK/PD of lefamulin against five Streptococcus pneumoniae and five Staphylococcus aureus strains using a neutropenic murine thigh infection model. The relationships between bacterial burden in the thigh of normal and neutropenic mice after 24 h of lefamulin treatment and various PK/PD indices were determined. RESULTS: The kinetics of the three doses was linear by AUC. Rate of killing was maximal at concentrations near the MIC; suppression of regrowth was dose dependent, with a post-antibiotic effect of 3.0-3.5 and 1.0-1.5 h against S. pneumoniae and S. aureus, respectively. The efficacy of lefamulin correlated most strongly with the AUC0-24/MIC ratio; coefficient of determination was 79.9% for S. pneumoniae and 78.3% for S. aureus. The magnitude of the 24 h AUC/MIC of total drug required ranged from 9.92 to 32.1 for S. pneumoniae and 40.2 to 82.5 for S. aureus, corresponding to free drug values (â¼20% free fraction) of 1.98-6.42 and 8.04-16.5, respectively. CONCLUSIONS: Lefamulin, the first systemically available pleuromutilin in humans, exhibits time- and concentration-dependent killing. The presence of white blood cells had only a slight effect in enhancing the activity of the drug, indicating a leucocyte-independent effect. The identified driver of efficacy, the AUC0-24/MIC ratio and the ratios determined against various S. aureus and S. pneumoniae strains, will inform further non-clinical and clinical trials.
Assuntos
Antibacterianos/uso terapêutico , Diterpenos/uso terapêutico , Neutropenia/microbiologia , Infecções Pneumocócicas/tratamento farmacológico , Compostos Policíclicos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Tioglicolatos/uso terapêutico , Animais , Antibacterianos/farmacocinética , Área Sob a Curva , Ciclofosfamida/administração & dosagem , Modelos Animais de Doenças , Diterpenos/farmacocinética , Feminino , Humanos , Injeções Subcutâneas , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Neutropenia/induzido quimicamente , Compostos Policíclicos/farmacocinética , Organismos Livres de Patógenos Específicos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Coxa da Perna/microbiologia , Tioglicolatos/farmacocinéticaRESUMO
OBJECTIVES: To present results of preclinical studies that supported further development of lefamulin for treating patients with community-acquired bacterial pneumonia (CABP). METHODS: The effect of bovine lung surfactant on the antibacterial activity of lefamulin against Streptococcus pneumoniae and Staphylococcus aureus was determined by broth microdilution assay. In vitro accumulation of lefamulin was evaluated in J774 mouse macrophages. Pharmacokinetics was assessed in female BALB/c (Bagg albino) mice treated with subcutaneous lefamulin (35 or 70 mg/kg). In neutropenic lung infection experiments, BALB/c mice received intraperitoneal cyclophosphamide before challenge with single S. pneumoniae or S. aureus strains; subcutaneous lefamulin (1.25-160 mg/kg) was given twice daily post-infection. Hill models described relationships between AUC/MIC ratios and changes in log10 cfu. RESULTS: Lung surfactant did not significantly increase lefamulin MIC values against test strains. Lefamulin uptake in macrophages was rapid (a plateau was reached in â¼3 h). In mice, distribution of lefamulin [plasma to epithelial lining fluid (ELF)] was rapid, showing an â¼2-fold increase in lefamulin exposure in the ELF during the 5.5 h period. Median plasma AUC/MIC ratios associated with 1 and 2 log10 cfu reductions from baseline were 1.37 and 2.15, respectively, for S. pneumoniae and 2.13 and 6.24 for S. aureus. Corresponding ELF results were 14.0 and 22.0 for S. pneumoniae and 21.7 and 63.9 for S. aureus. CONCLUSIONS: Overall, lefamulin displays desirable pharmacokinetic/pharmacodynamic relationships that are predictive of the clinical effectiveness of lefamulin and other antibacterial agents used to treat CABP.
Assuntos
Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Diterpenos/farmacocinética , Diterpenos/uso terapêutico , Neutropenia/microbiologia , Pneumonia Pneumocócica/tratamento farmacológico , Compostos Policíclicos/farmacocinética , Compostos Policíclicos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Tioglicolatos/farmacocinética , Tioglicolatos/uso terapêutico , Animais , Área Sob a Curva , Bovinos , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Ciclofosfamida/administração & dosagem , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Injeções Subcutâneas , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Neutropenia/induzido quimicamente , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Tensoativos/farmacologiaRESUMO
Two clinical studies were performed in healthy volunteers to investigate food and antacid effects on lesinurad, a novel selective uric acid reabsorption inhibitor approved for treatment of hyperuricemia associated with gout in combination with xanthine oxidase inhibitors. Study 1 evaluated a high-fat, high-calorie meal or high doses of antacids (3000 mg calcium carbonate or 1600 mg magnesium hydroxide/1600 mg aluminum hydroxide) on the pharmacokinetics (PK) and pharmacodynamics (PD) of 400 mg oral lesinurad. Study 2 evaluated low doses of antacids (1250 mg calcium carbonate or 800 mg magnesium hydroxide/800 mg aluminum hydroxide) on the PK and PD of 400 mg lesinurad. Food did not alter the plasma AUC of lesinurad and only reduced its Cmax by 18%. In the fasted conditions, high-dose calcium carbonate reduced the Cmax and AUC of lesinurad by 54% and 38%, respectively, whereas high-dose magnesium hydroxide/aluminum hydroxide reduced Cmax and AUC by 36% and 31%, respectively. Food enhanced the maximum serum urate (sUA)-lowering effect of lesinurad by approximately 20% despite reducing the Cmax of lesinurad. High-dose calcium carbonate decreased the urate-lowering effect approximately 20% in the first 6 hours, whereas high-dose magnesium hydroxide/aluminum hydroxide reduced the effect by 26%. Low-dose calcium carbonate or magnesium hydroxide/aluminum hydroxide in the presence of food did not significantly affect plasma lesinurad Cmax and AUC or the sUA lowering and renal handling of uric acid. In summary, study results suggest food did not meaningfully alter lesinurad PK and PD. High doses of antacids reduced lesinurad AUC up to 40% and reduced the lesinurad uric acid-lowering effect.
Assuntos
Hidróxido de Alumínio/farmacologia , Antiácidos/farmacologia , Carbonato de Cálcio/farmacologia , Interações Alimento-Droga , Supressores da Gota , Hidróxido de Magnésio/farmacologia , Tioglicolatos , Triazóis , Ácido Úrico/sangue , Adolescente , Adulto , Estudos Cross-Over , Gorduras na Dieta/administração & dosagem , Combinação de Medicamentos , Supressores da Gota/sangue , Supressores da Gota/farmacocinética , Supressores da Gota/farmacologia , Supressores da Gota/urina , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Tioglicolatos/sangue , Tioglicolatos/farmacocinética , Tioglicolatos/farmacologia , Tioglicolatos/urina , Triazóis/sangue , Triazóis/farmacocinética , Triazóis/farmacologia , Triazóis/urina , Adulto JovemRESUMO
BACKGROUND: Lefamulin, a pleuromutilin antibiotic, is active against pathogens commonly causing community-acquired bacterial pneumonia (CABP). The Lefamulin Evaluation Against Pneumonia (LEAP 1) study was a global noninferiority trial to evaluate the efficacy and safety of lefamulin for the treatment of CABP. METHODS: In this double-blind study, adults with CABP of Pneumonia Outcomes Research Team risk class ≥III were randomized 1:1 to receive lefamulin at 150 mg intravenously (IV) every 12 hours or moxifloxacin at 400 mg IV every 24 hours. After 6 doses, patients could be switched to an oral study drug if prespecified improvement criteria were met. If methicillin-resistant Staphylococcus aureus was suspected, either linezolid or placebo was added to moxifloxacin or lefamulin, respectively. The US Food and Drug Administration primary endpoint was an early clinical response (ECR) 96 ± 24 hours after the first dose of the study drug in the intent-to-treat (ITT) population (noninferiority margin, 12.5%). The European Medicines Agency co-primary endpoints were an investigator assessment of clinical response (IACR) 5-10 days after the last dose of the study drug in the modified ITT (mITT) and clinically evaluable (CE) populations (noninferiority margin, 10%). RESULTS: There were 551 patients randomized (n = 276 lefamulin; n = 275 moxifloxacin). Lefamulin was noninferior to moxifloxacin for ECR (87.3% vs 90.2%, respectively; difference -2.9%, 95% confidence interval [CI] g -8.5 to 2.8) and IACR (mITT, 81.7% vs 84.2%, respectively; difference -2.6%, 95% CI -8.9 to 3.9; CE, 86.9% vs 89.4%, respectively; difference -2.5%, 95% CI -8.4 to 3.4). Rates of study drug discontinuation due to treatment-emergent adverse events were 2.9% for lefamulin and 4.4% for moxifloxacin. CONCLUSIONS: Lefamulin was noninferior to moxifloxacin for the primary efficacy endpoints and was generally safe and well tolerated. CLINICAL TRIALS REGISTRATION: NCT02559310.
Assuntos
Diterpenos/uso terapêutico , Moxifloxacina/uso terapêutico , Pneumonia Bacteriana/tratamento farmacológico , Compostos Policíclicos/uso terapêutico , Tioglicolatos/uso terapêutico , Administração Intravenosa , Adulto , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Diterpenos/administração & dosagem , Diterpenos/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Linezolida/efeitos adversos , Linezolida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Moxifloxacina/administração & dosagem , Moxifloxacina/efeitos adversos , Pneumonia Bacteriana/metabolismo , Compostos Policíclicos/administração & dosagem , Compostos Policíclicos/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tioglicolatos/administração & dosagem , Tioglicolatos/efeitos adversos , PleuromutilinasRESUMO
Lefamulin, the first semisynthetic pleuromutilin antibacterial for intravenous and oral treatment of community-acquired bacterial pneumonia (CABP), and comparators were evaluated for in vitro activity against a global collection of pathogens commonly causing CABP (n = 8595) from the 2015 and 2016 SENTRY Antimicrobial Surveillance Program. Lefamulin was highly active against the pathogens Streptococcus pneumoniae, including multidrug-resistant and extensively drug-resistant strains (MIC50/90 for total and resistant subsets, 0.06/0.12 µg/ml; 100% inhibited at ≤1 µg/ml), Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus (MRSA; both MIC50/90, 0.06/0.12 µg/ml; 99.8% and 99.6% inhibited at ≤1 µg/ml, respectively), Haemophilus influenzae (MIC50/90, 0.5/1 µg/ml; 93.8% inhibited at ≤1 µg/ml), and Moraxella catarrhalis (MIC50/90, 0.06/0.12 µg/ml; 100% inhibited at ≤0.25 µg/ml), and its activity was unaffected by resistance to other antibacterial classes.
Assuntos
Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Diterpenos/uso terapêutico , Pneumonia Bacteriana/tratamento farmacológico , Compostos Policíclicos/uso terapêutico , Tioglicolatos/uso terapêutico , Infecções Comunitárias Adquiridas/microbiologia , Infecções por Haemophilus/tratamento farmacológico , Haemophilus influenzae/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/efeitos dos fármacos , Infecções por Moraxellaceae/tratamento farmacológico , Infecções Pneumocócicas/tratamento farmacológico , Pneumonia Bacteriana/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Streptococcus pneumoniae/efeitos dos fármacosRESUMO
This study investigated the molecular mechanisms possibly associated with non-wild-type MICs for lefamulin among staphylococci and streptococci included in the lefamulin surveillance program from 2015 to 2016. A total of 2,919 Staphylococcus aureus, 276 coagulase-negative staphylococci (CoNS), 3,923 Streptococcus pneumoniae, 389 ß-hemolytic, and 178 viridans group streptococci isolates were included in the surveillance studies. Eleven (0.3% of all S. aureus) S. aureus isolates with lefamulin MICs above the staphylococcal epidemiological cutoff (ECOFF) value (>0.25 µg/ml) were selected for this study. Eight (72.7%) S. aureus (lefamulin MIC, 0.5 to 4 µg/ml) isolates carried vga(A or E), one isolate (MIC, 32 µg/ml) carried lsa(E), one isolate (MIC, 16 µg/ml) had an alteration in L4, and one strain (MIC, 0.5 µg/ml) did not carry any of the investigated resistance mechanisms. A total of 14 (5.1% of all CoNS) CoNS isolates had lefamulin MICs (0.5 to >32 µg/ml) above the ECOFF. Similar to S. aureus, 8 (57.1%) CoNS (lefamulin MIC, 1 to 8 µg/ml) isolates carried vga(A or B), while 2 isolates (MIC, 4 to 32 µg/ml) carried cfr High genetic diversity was observed among staphylococci, although 3 S. aureus isolates belonged to sequence type 398 (ST398). Among the 3 Streptococcus agalactiae and 3 viridans group streptococci (0.1% of all streptococci surveyed) isolates selected for additional characterization, all but 1 isolate carried lsa(E). This study documents a low occurrence of surveillance isolates exhibiting a non-wild-type MIC for lefamulin, and among these isolates, vga and lsa(E) prevailed in staphylococci and streptococci, respectively.
Assuntos
Antibacterianos/uso terapêutico , Diterpenos/uso terapêutico , Infecções Pneumocócicas/epidemiologia , Compostos Policíclicos/uso terapêutico , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Tioglicolatos/uso terapêutico , Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Bactérias/genética , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Streptococcus agalactiae/isolamento & purificação , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
The emergence and spread of antimicrobial resistance have led to a global public health emergency requiring development of new antimicrobial classes. Lefamulin (formally BC-3781) is a novel pleuromutilin antibiotic currently undergoing Food and Drug Administration review for community-acquired bacterial pneumonia (CABP) as intravenous (IV) and oral (PO) formulations. Although pleuromutilin antibiotics were first developed in the 1950s, lefamulin is the first to be used for systemic treatment of bacterial infections in humans. Lefamulin exhibits a unique mechanism of action through inhibition of protein synthesis by binding to the peptidyl transferase center of the 50S bacterial ribosome, thus preventing the binding of transfer RNA for peptide transfer. Lefamulin displays activity against gram-positive and atypical organisms associated with CABP (i.e., Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Legionella pneumophila, and Chlamydophila pneumoniae), with an expanded gram-positive spectrum including Staphylococcus aureus (i.e., methicillin-resistant, vancomycin-intermediate, and heterogeneous strains) and vancomycin-resistant Enterococcus faecium. Lefamulin was also shown to retain activity against multidrug-resistant Neisseria gonorrhoeae and Mycoplasma genitalium. Lefamulin exhibits time-dependent killing, and the pharmacodynamic target best associated with antibacterial activity is ƒAUC0-24 /MIC (minimum inhibitory concentration [MIC]). Preclinical and phase II trials indicate that lefamulin concentrates in lung tissue are well tolerated at an IV dose of 150 mg twice/day over 1 hour or a PO dose of 600 mg twice/day, and preliminary phase III data suggest similar efficacy when compared with moxifloxacin with or without linezolid in CABP. Documented resistance and cross-resistance with other gram-positive antibacterials remains low. Additional published in vitro, in vivo, and preclinical trial data suggest further exploration of lefamulin in various infectious disease states (e.g., acute bacterial skin and skin structure infections, and sexually transmitted infections). This review discusses the pertinent bacterial spectrum of activity, preclinical and ongoing clinical data, and potential roles in therapy for lefamulin.
Assuntos
Antibacterianos/uso terapêutico , Diterpenos/uso terapêutico , Tioglicolatos/uso terapêutico , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/tratamento farmacológico , Diterpenos/efeitos adversos , Diterpenos/farmacocinética , Diterpenos/farmacologia , Resistência a Medicamentos , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Compostos Policíclicos , Tioglicolatos/efeitos adversos , Tioglicolatos/farmacocinética , Tioglicolatos/farmacologiaRESUMO
The initiation of torpor is supposed to be related to the availability of metabolic fuels. Studies on metabolic fuel inhibition of glucose by using 2-deoxy-D-glucose (2DG) or fatty acid by mercaptoacetate (MA) in heterothermic mammals produced mixed outcomes. To examine the roles of availability of glucose and fatty acid in the initiation of torpor in desert hamsters (Phodopus roborovskii), we intraperitoneally administrated 2DG and MA to summer-acclimated male hamsters while body temperature (Tb), metabolic rate (MR) and respiratory quotient (RQ) were simultaneously recorded to monitor their thermoregulatory response. 2DG induced a reversible reduction of Tb in desert hamsters both at ambient temperature (Ta) of 23°C and 5°C. At Ta of 23°C, Tb, MR and RQ decreased in a dose-dependent manner with a large Tb-Ta differential (> 6.5°C) and a lowest Tb of 28.0°C which were comparable to those in fasted hamsters. At Ta of 5°C, 2DG-treated hamsters also decreased Tb to the same level as at Ta 23°C, but MR was significantly higher than that at Ta of 23°C at each dose, suggesting doses of 2DG directly affected the hypothalamic Tb set-point. Different from fasted hamsters which maintain normothermic at Ta of 5°C, 2DG-treated hamsters showed a substantial reduction of Tb at Ta 5°C, indicating an overwhelming effect on the thermoregulatory system regardless of Ta. Furthermore, the rapid decrease of Tb and outstretched body posture in 2DG-treated hamsters suggest that the effects of 2DG were not simply mimicking the torpor pathways but that other mechanisms are involved. Interestingly, MA failed to induce a torpor-like state in male desert hamsters. Our results suggest that availability of glucose rather than fatty acid plays an important role for initiation of torpor in desert hamsters.
Assuntos
Antimetabólitos/farmacologia , Temperatura Corporal/efeitos dos fármacos , Desoxiglucose/farmacologia , Phodopus/fisiologia , Tioglicolatos/farmacologia , Animais , Metabolismo Basal , Cricetinae , Hipotálamo/fisiologia , Masculino , Respiração , Torpor/efeitos dos fármacosRESUMO
Inspired by the high reactivity and specificity of thiyl radicals toward alkenes, we have developed a new charge derivatization method to enable fast and quantitative analysis of sterols via electrospray ionization-mass spectrometry (ESI-MS). Thioglycolic acid (TGA), a commercially available compound, has been established as a highly efficient tagging reagent. Initiated from photochemical reactions, the thiyl radical derived from TGA abstracts an allylic hydrogen in the B ring of sterols, forming a radical intermediate which rapidly recombines with a second thiyl radical to produce the final tagged product. Because of the incorporation of a carboxylic acid group, TGA tagging not only improves the limit of detection (sub-nM) for sterols but also facilitates their quantitation via characteristic 44 Da neutral loss scan. This radical based derivatization is fast (1 min) and efficient (>90% yield) when conducted in a flow microreactor. The analytical utility of thiyl radical charge tagging method has been demonstrated by quantifying sterols from human plasma and vegetable oil.
Assuntos
Fitosteróis/sangue , Humanos , Isomerismo , Limite de Detecção , Fitosteróis/química , Óleo de Soja/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Tioglicolatos/químicaRESUMO
OBJECTIVE: To study the anti-inflammatory properties of OJ. CONTEXT: Ojayeonjonghwan (OJ) is a traditional Korean prescription, which has been widely used for the treatment of prostatitis. However, no scientific study has been performed of the anti-inflammatory effects of OJ. MATERIALS AND METHODS: Peritoneal macrophages were isolated 3-4 days after injecting a C57BL/6J mouse with thioglycollate. They were then treated with OJ water extract (0.01, 0.1, and 1 mg/mL) for 1 h and stimulated with lipopolysaccharide (LPS) for different times. Nitric oxide (NO), inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and proinflammatory cytokine levels were determined by NO assay, Western blotting, RT-PCR and ELISA. RESULTS: NO generation and iNOS induction were increased in the LPS-activated mouse peritoneal macrophages. However, NO generation and iNOS induction by LPS were suppressed by treatment with OJ for the first time. The IC50 value of OJ with respect to NO production was 0.09 mg/mL. OJ did not influence LPS-stimulated COX-2 induction, but did significantly decrease LPS-stimulated secretions and mRNA expressions of tumour necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1ß. Inhibition rates of TNF-α, IL-6, and IL-1ß at an OJ concentration of 1 mg/mL were 77%, 88%, and 50%, respectively. OJ also suppressed the LPS-induced nuclear translocation of NF-κB. High-performance liquid chromatography showed schizandrin and gomisin A are major components of OJ. CONCLUSIONS: OJ reduces inflammatory response, and this probably explains its positive impact on the prostatitis associated inflammation.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ciclo-Octanos/farmacologia , Dioxóis/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Lignanas/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Compostos Policíclicos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/química , Células Cultivadas , Ciclo-Octanos/análise , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dioxóis/análise , Etnofarmacologia , Lignanas/análise , Lipopolissacarídeos/toxicidade , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Medicina Tradicional Coreana , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/química , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/química , Compostos Policíclicos/análise , Prostatite/tratamento farmacológico , Prostatite/imunologia , Prostatite/metabolismo , Prostatite/patologia , TioglicolatosRESUMO
BACKGROUND: Recent studies suggest that purified omega-3 fatty acids may attenuate acute inflammation and hasten the transition to healing. In this study, we tested the hypothesis that pretreatment with omega-3-rich fish oil (FO) would promote resolution of peritoneal inflammation through production of specific lipid mediators. METHODS: C57/BL6 mice were given a daily 200-µL oral gavage of saline (CTL) or FO (1.0-1.5 g/kg/d docosahexaenoic acid and 1.3-2.0 g/kg/d eicosapentaenoic acid) for 7 d before chemical peritonitis was induced with thioglycollate. Peritoneal lavage fluid was collected before induction and at days 2 and 4 after peritonitis onset. Prostaglandin E2 (PGE2), Leukotriene B4 (LTB4), Resolvin D1 (RvD1), and the composition of immune cell populations were examined in peritoneal lavage exudates. Cells harvested from the peritoneum were assessed for macrophage differentiation markers, phagocytosis, and lipopolysaccharide-induced cytokine secretion profiles (interleukin [IL]-6, IL-10, IL-1ß, TNFα). RESULTS: The ratio of RvD1 to pro-inflammatory PGE2 and LTB4 was increased in the peritoneal cavity of FO-supplemented animals. FO induced a decrease in the number of monocytes in the lavage fluid, with no change in the number of macrophages, neutrophils, or lymphocytes. Macrophage phagocytosis and M1/M2 messenger RNA markers were unchanged by FO with the exception of decreased PPARγ expression. FO increased ex vivo TNFα secretion after stimulation with lipopolysaccharide. CONCLUSIONS: Our findings provide evidence that nutraceutically relevant doses of FO supplements given before and during chemical peritonitis shift the balance of lipid mediators towards a proresolution, anti-inflammatory state without drastically altering the number or phenotype of local innate immune cell populations.
Assuntos
Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácido Eicosapentaenoico/uso terapêutico , Peritonite/prevenção & controle , Administração Oral , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peritonite/induzido quimicamente , Peritonite/imunologia , Peritonite/metabolismo , TioglicolatosRESUMO
The surface of gold nanoparticles (AuNP) was modified, improving their interaction with neutral red (NR), by using sodium thioglycolate (TGA) as a covering agent. The resulting NR-AuNPTGA system was evaluated as a potential drug delivery system for photodynamic therapy (PDT). The associations of NR with the gold nanoparticles were evaluated using UV-vis spectrometry and measurement of their zeta potential and size distribution. The toxicity and phototoxicity of NR, AuNPTGA and NR-AuNPTGA were evaluated in NIH-3T3 fibroblast and 4T1 tumor cell lines. The compounds NR and NR-AuNPTGA induced toxicity in 4T1 tumor cells and NIH-3T3 fibroblasts under visible light irradiation. Modification of the surface of AuNP with TGA prevented nanoparticle aggregation and allowed greater association with NR molecules than for naked AuNP. The photosensitizer (PS) characteristics were not affected by its association with the modified surface of the gold nanoparticles, leading to a reduction of cell viability in both cell lines assayed. This NR-AuNPTGA system is a promising drug delivery system for photodynamic cancer therapy.
Assuntos
Portadores de Fármacos/química , Ouro/química , Nanopartículas Metálicas/química , Vermelho Neutro/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Humanos , Luz , Nanopartículas Metálicas/toxicidade , Camundongos , Células NIH 3T3 , Neoplasias/tratamento farmacológico , Vermelho Neutro/administração & dosagem , Vermelho Neutro/toxicidade , Tamanho da Partícula , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/toxicidade , Espectrofotometria Ultravioleta , Eletricidade Estática , Propriedades de Superfície , Tioglicolatos/químicaRESUMO
Highly fluorescent and biocompatible soft materials are desirable for many potential applications, but their synthetic processes are somehow complicated. Herein, we have explored the feasibility of synthesis of unconventional fluorescence soft materials from small organic molecules under mild conditions. A new blue-fluorescent soft material with high quantum yield (89.6 %) and eutectic feature prepared by simple heat treatment of citric acid (CA) and cysteine (Cys) aqueous mixtures below 100 °C in air was reported. The as-prepared fluorescent material has the features of facile preparation, low cost, scalable production and easy to process, making it suitable for applications like fluorescent labeling and light-emitting devices. This new finding opens a new venue for the preparation of fluorescent soft materials.
Assuntos
Ácido Cítrico/química , Cisteína/química , Corantes Fluorescentes/química , Géis/química , Glicina/química , Glicolatos/química , Espectroscopia Fotoeletrônica , Teoria Quântica , Espectrometria de Fluorescência , Eletricidade Estática , Propriedades de Superfície , Temperatura , Tioglicolatos/química , Raios UltravioletaRESUMO
Antimicrobial, antifungal and anti-inflammatory effects of essential oils extracted from Chamaecyparis obtusa (EOCO) have previously been reported. In the present study, the anti-inflammatory effects of EOCO were investigated in two murine models of inflammation: Carrageenan-induced paw edema and thioglycollate-induced peritonitis, and in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The expression levels of proinflammatory cytokines were analyzed by ELISA, the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were determined by western blotting, and nitrite concentration was measured using Griess reagent. In mice with carrageenan-induced edema, paw thickness and the expression levels of interleukin (IL)1ß and IL-6 in paw homogenates were significantly decreased in the EOCO (5 and 10 mg/kg) group, as compared with the control group. In mice with thioglycollate-induced peritonitis, treatment with EOCO (5 and 10 mg/kg) reduced the number of total cells and suppressed tumor necrosis factorα (TNFα), IL1ß and IL6 levels in peritoneal fluid. In addition, EOCO reduced nitric oxide, TNFα and IL6 production, and suppressed iNOS and COX2 expression in LPSstimulated RAW 264.7 cells. These results suggest that EOCO may exert antiinflammatory effects in vivo and in vitro, and that these effects may be associated with the inhibition of inflammatory mediators. Therefore, EOCO may be considered an effective therapeutic agent for the treatment of inflammatory diseases.
Assuntos
Anti-Inflamatórios/uso terapêutico , Chamaecyparis/química , Edema/tratamento farmacológico , Óleos Voláteis/uso terapêutico , Peritonite/tratamento farmacológico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Carragenina/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Chamaecyparis/metabolismo , Ciclo-Oxigenase 2/metabolismo , Citocinas/análise , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/patologia , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/análise , Óxido Nítrico Sintase Tipo II/metabolismo , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Peritonite/induzido quimicamente , Peritonite/patologia , Células RAW 264.7 , Tioglicolatos/toxicidadeRESUMO
BACKGROUND: School-aged children living in the vicinity of vinyl chloride (VCM)/polyvinyl chloride (PVC) factories may have an increased risk of exposure to hazardous air pollutants. OBJECTIVES: We aimed to evaluate the urinary thiodiglycolic acid (TDGA) level, as TDGA is a major metabolite of VCM, for students at elementary schools near a petrochemical complex in central Taiwan. METHODS: We recruited 343 students from 5 elementary schools based on distance to the VCM/PVC factory. First-morning urine and blood samples were obtained from our subjects from October 2013 to September 2014. Urine samples were analyzed for urinary creatinine and TDGA using LC/MS-MS. Hepatitis virus infection were assessed using blood samples. We determined their vitamin consumption, resident location, parent's employment, and other demographic or lifestyle characteristics using a questionnaire. RESULTS: Median urinary TDGA levels for 316 students at 5 elementary schools from the closest (<.9km) to the farthest (â¼8.6km) with respect to the petrochemical complex were 147.6, 95.5, 115.5, 86.8, and 17.3µg/g creatinine, respectively. After adjusting for age, gender, hepatitis virus infection, vitamin B consumption, passive smoking, and home to source distance, we found that urinary TDGA levels for the closest students was significantly higher than those at other schools. Further, median urinary TDGA levels for students during school time were 4.1-fold higher than those during summer vacation. CONCLUSIONS: After adjusting for confounders, urinary TDGA levels for the school-aged children decreased with increasing distances between the elementary schools and the petrochemical complex.