Five-day moxifloxacin therapy compared with 7-day co-amoxiclav therapy for the treatment of acute exacerbation of chronic bronchitis

Lung infarction secondary to infected pulmonary arterial thrombosis in a patient with Eisenmenger's syndrome

A case is presented where a patient with Eisenmenger's syndrome is successfully treated for infection of chronic pulmonary arterial thrombosis with good effect. The evidence for antibiotic and anticoagulant therapy in this patient group is discussed.

Network meta-analysis of success rate and safety in antibiotic treatments of bronchitis

The purpose of this study was to compare the relative efficacy and safety of different antibiotic drugs and recommend superior regimens in the treatment of bronchitis. With respect to the antibiotic comparisons against quinolones in terms of intention-to-treat patients, we concluded that quinolones had advantages over placebo, β-lactams, sulfonamides, and double β-lactams. Concerning treatment methods for clinically evaluable patients, quinolones demonstrated better performance than β-lactams and sulfonamides. The secondary effects of macrolides, quinolones, and double β-lactams were significantly more adverse than β-lactams with odds ratios (ORs) of 1.5 (95% credible interval [CrI] =1.1–2.0), 1.7 (95% CrI =1.2–2.3), and 2.7 (95% CrI =1.8–4.1), respectively. Significant differences in the prevalence of diarrhea as a secondary effect were only identified among the comparisons of double β-lactams against β-lactams and macrolides (OR =5.0, 95% CrI =2.1–12.0; OR =3.0, 95% CrI =1.7–5.4, respectively). Quinolones can be recommended as the superior treatment for bronchitis, in accordance with our cluster analysis with surface under the cumulative ranking curve. The primary outcomes of network meta-analysis indicated that quinolones showed the best performance among the 8 treatments studied, although β-lactams showed the lowest risk of adverse side effects. Quinolones are recommended as the primary treatment option for bronchitis patients, having taking into account the success rates and safety profiles of the eight drugs studied here.

Comparison of Pathogen Eradication Rate and Safety of Anti-Bacterial Agents for Bronchitis: A Network Meta-Analysis

A large number of population in both developing and developed countries are affected by bronchitis, among all the factors, bacterial infection was considered as a critical cause of acute exacerbations of chronic bronchitis. Although several anti-bacterial agents were proved to have the effect of alleviating bronchitis, their relative efficacies and potential side effects remained not clear. We are keen to compare the pathogen eradication rate and safety of anti-bacterial agents for bronchitis. Relevant studies were searched in multiple sources and data were extracted from eligible studies. Then conventional meta-analysis and network meta-analysis (NMA) were conducted to determine the relative efficacy and safety of bronchitis medications. The efficacy of bronchitis medications was determined by using the outcome of pathogen eradication, including total pathogen eradication, pathogen eradication of Haemophilus influenzae, pathogen eradication of Moraxella catarrhalis, and pathogen eradication of Streptococcus pneumoniae. In addition, safety was assessed by using the outcome of adverse effects and diarrhoea. A 27 RCTs with 9,414 participants were included in the study. Among the medications, gatifloxacin and moxifloxacin exhibited better performance than clarithromycin with respect to pathogen eradication of H. influenzae (OR = 21.37, CI: 1.22-541.28; OR = 7.43, CI: 1.79-30.50). Clarithromycin, gemifloxacin, levofloxacin, moxifloxacin, and telithromycin appeared to be more preferable than amoxicillin + clavulanate and azithromycin with respect to diarrhoea (all OR <1). The surface under the cumulative ranking curve (SUCRA) results suggested that gemifloxacin and levofloxacin had a relatively high ranking in total pathogen eradication, whereas amoxicillin + clavulanate and azithromycin exhibited relatively lower ranking with respect to adverse effects and diarrhoea. Gemifloxacin and levofloxacin are more preferable than others for lowering respiratory tract inflammation and infections considering their balanced performance between pathogen eradication and adverse effects. J. Cell. Biochem. 118: 3171-3183, 2017. © 2017 Wiley Periodicals, Inc.

In Vivo Pharmacokinetic and Pharmacodynamic Profiles of Antofloxacin against Klebsiella pneumoniae in a Neutropenic Murine Lung Infection Model

Antofloxacin is a novel broad-spectrum fluoroquinolone under development for the treatment of infections caused by a diverse group of bacterial species. We explored the pharmacodynamic (PD) profile and targets of antofloxacin against seven Klebsiella pneumoniae isolates by using a neutropenic murine lung infection model. Plasma and bronchopulmonary pharmacokinetic (PK) studies were conducted at single subcutaneous doses of 2.5, 10, 40, and 160 mg/kg of body weight. Mice were infected intratracheally with K. pneumoniae and treated using 2-fold-increasing total doses of antofloxacin ranging from 2.5 to 160 mg/kg/24 h administered in 1, 2, 3, or 4 doses. The E_max Hill equation was used to model the dose-response data. Antofloxacin could penetrate the lung epithelial lining fluid (ELF) with pharmacokinetics similar to those in plasma with linear elimination half-lives over the dose range. All study strains showed a 3-log₁₀ or greater reduction in bacterial burden and prolonged postantibiotic effects (PAEs) ranging from 3.2 to 5.3 h. Dose fractionation response curves were steep, and the free-drug area under the concentration-time curve over 24 h (AUC_0-24)/MIC ratio was the PD index most closely linked to efficacy (R² = 0.96). The mean free-drug AUC_0-24/MIC ratios required to achieve net bacterial stasis, a 1-log₁₀ kill, and a 2-log₁₀ kill for each isolate were 52.6, 89.9, and 164.9, respectively. When integrated with human PK data, these PD targets could provide a framework for further optimization of dosing regimens. This could make antofloxacin an attractive option for the treatment of respiratory tract infections involving K. pneumoniae.

Zabofloxacin versus moxifloxacin in patients with COPD exacerbation: a multicenter, double-blind, double-dummy, randomized, controlled, Phase III, non-inferiority trial

A new quinolone, zabofloxacin, has now been developed; hence, a non-inferiority trial is needed to compare this new compound with another widely used quinolone to examine its efficacy and safety for the treatment of chronic obstructive pulmonary disease (COPD) exacerbations. This was a prospective, multicenter, double-blind, double-dummy, randomized, controlled, parallel-group, Phase III, non-inferiority clinical trial designed to compare oral zabofloxacin (367 mg once daily for 5 days) with moxifloxacin (400 mg once daily for 7 days) for the treatment of patients with COPD exacerbation. In all, 345 COPD patients with a moderate COPD exacerbation were enrolled in the study via the outpatient clinics at 31 university hospitals. Clinical per protocol analysis revealed that the clinical cure rate for zabofloxacin was 86.7% and that for moxifloxacin was 86.3% (the rate difference, 0.4%; 95% confidence interval, −7.7%–8.6%). Intention-to-treat analysis revealed clinical cure rates of 77.1% and 77.3% (difference, −0.2%; 95% confidence interval, −9.0%–8.8%), respectively. These results confirm that zabofloxacin is not inferior to moxifloxacin. The favorable microbiological response rate for zabofloxacin was 67.4% and that for moxifloxacin was 79.5% (P=0.22). Patients in the zabofloxacin group showed better patient-oriented outcomes, as measured by EXAcerbations of Chronic Pulmonary Disease Tool-Patient-Reported Outcome and the COPD assessment test scores, than patients in the moxifloxacin group. Adverse drug reactions related to zabofloxacin occurred in 9.7% of cases and those related to moxifloxacin occurred in 9.6% of cases (P=0.97). The dropout rate due to adverse events was 0% (0/175) in the zabofloxacin group and 1.8% (3/167) in the moxifloxacin group (P=0.12). Oral zabofloxacin (367 mg once daily for 5 days) was not inferior to oral moxifloxacin (400 mg once daily for 7 days) for the treatment of patients with COPD exacerbation.

Efficacy and safety of moxifloxacin in acute exacerbations of chronic bronchitis and COPD: a systematic review and meta-analysis

PURPOSE

To evaluate the efficacy and safety of moxifloxacin in acute exacerbations of chronic bronchitis (AECB) and chronic obstructive pulmonary disease (AECOPD).

METHODS

We searched PubMed, EMBASE, and the Web of Science for relevant studies. Two reviewers extracted data and reviewed the quality of the studies independently. The primary outcome was clinical success at early follow-up. Study-level data were pooled using a random-effects model when I(2) was >50% or a fixed-effects model when I(2) was <50%.

RESULTS

Eleven randomized controlled studies were considered. There was no difference between moxifloxacin and comparator agents with regard to treatment success in intention-to-treat (ITT) [odds ratio (OR) =1.18, 95% confidence interval (CI) 0.98-1.42], clinically evaluable (CE) (OR 1.13, 95% CI, 0.93-1.37) patients, or adverse effects in general (OR 1.00, 95% CI, 0.86-1.17). Moxifloxacin was associated with better microbiological success (OR 1.45; 95% CI, 1.14-1.85).

CONCLUSIONS

Moxifloxacin was as clinically equivalent and bacteriologically superior to the antibiotic regimens routinely used in patients with AECB and AECOPD. Moxifloxacin therapy may be a promising and safe alternative to empirical treatment for AECB and AECOPD.

Gender analysis of moxifloxacin clinical trials

PURPOSE

To determine the inclusion of women and the sex-stratification of results in moxifloxacin Clinical Trials (CTs), and to establish whether these CTs considered issues that specifically affect women, such as pregnancy and use of hormonal therapies. Previous publications about women's inclusion in CTs have not specifically studied therapeutic drugs. Although this type of drug is taken by men and women at a similar rate, adverse effects occur more frequently in the latter.

METHODS

We reviewed 158 published moxifloxacin trials on humans, retrieved from MedLine and the Cochrane Library (1998-2010), to determine whether they complied with the gender recommendations published by U.S. Food and Drug Administration Guideline.

RESULTS

Of a total of 80,417 subjects included in the moxifloxacin CTs, only 33.7% were women in phase I, in contrast to phase II, where women accounted for 45%, phase III, where they represented 38.3% and phase IV, where 51.3% were women. About 40.9% (n=52) of trials were stratified by sex and 15.3% (n=13) and 9% (n=7) provided data by sex on efficacy and adverse effects, respectively. We found little information about the influence of issues that specifically affect women. Only 3 of the 59 journals that published the moxifloxacin CTs stated that authors should stratify their results by sex.

CONCLUSIONS

Women are under-represented in the published moxifloxacin trials, and this trend is more marked in phase I, as they comprise a higher proportion in the other phases. Data by sex on efficacy and adverse effects are scarce in moxifloxacin trials. These facts, together with the lack of data on women-specific issues, suggest that the therapeutic drug moxifloxacin is only a partially evidence-based medicine.

Antibiotic therapy in elderly patients with acute exacerbation of chronic bronchitis

Chronic bronchitis (CB) is a critical component of chronic obstructive pulmonary disease (COPD). Emphysema, reversible airway disease and bronchiectasis also contribute to COPD. Elderly patients are at increased risk for COPD and its components - emphysema, CB and bronchiectasis. In addition, older patients are at increased risk for resistant organisms during episodes of acute exacerbation of CB (AECB). These organisms include the more common bacteria implicated in AECB, such as Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae, and less common nonenteric, Gram-negative organisms such as Pseudomonas aeruginosa. Risk-stratified antibiotic treatment guidelines for AECB appear to be useful, although they have not been prospectively validated for the general CB population, and especially not in the elderly CB population. Many of the AECB treatment guidelines that are stratified based on risk factors have recommended that the oral respiratory fluoroquinolone antibiotics (gemifloxacin, levofloxacin and moxifloxacin) play a second-line but pivotal role, particularly in patients who have failed initial antibiotic treatment for simple CB or as initial treatment for complicated CB.

Short-course fluoroquinolones in acute exacerbations of chronic bronchitis

It is estimated that 50-70% of acute exacerbations of chronic bronchitis (AECB) are caused by bacterial infections. Appropriate selection of antimicrobials may lead to better outcomes and reduced healthcare costs. Respiratory fluoroquinolones (moxifloxacin, levofloxacin and gemifloxacin) have a broad spectrum of activity against most AECB-causing pathogens and are used as first-line treatment in patients with comorbidity, severe airway obstruction or recurrent exacerbations. We review studies, identified through a MEDLINE search, that compared clinical efficacy and speed of recovery for short-course (≤ 5 days) fluoroquinolone therapy with commonly prescribed standard therapy (≥ 7 days). Among 177 studies reporting the use of fluoroquinolones for AECB treatment, 23 used a short-course regimen, shown to be at least as effective as standard therapy of 7 or more days duration. Furthermore, evidence suggests that short-course therapy offers faster resolution of symptoms, faster rate of recovery, fewer relapses, fewer and shorter hospitalizations, and longer time between recurrences.

Antibiotics in acute exacerbations of chronic bronchitis

Acute exacerbations of chronic bronchitis (AECB) are a major contributor to morbidity and mortality in patients with chronic obstructive pulmonary disease, accounting for more than 16 million physician office visits and over 500,000 hospitalizations in the USA each year. Antimicrobials have been recognized by clinical guidelines as an important component in the management of AECB with a bacterial etiology. The challenge of identifying patients most likely to benefit from antimicrobial therapy is difficult in the clinical setting. However, appropriate risk stratification of patients, and the use of antimicrobials within the correct spectrum and for a suitable duration, can improve clinical outcomes while minimizing induction of antimicrobial resistance. With an improved design in pharmacologic and clinical studies, differences can be appreciated among the various antimicrobial agents available to treat AECB. Factors to be considered in antimicrobial agent selection include local tissue penetration, effects on bacteriological eradication, duration of therapy, speed of resolution and prevention or delay of recurrences.

The diagnosis and treatment of elderly patients with acute exacerbation of chronic obstructive pulmonary disease and chronic bronchitis

The syndrome of chronic obstructive pulmonary disease (COPD) consists of chronic bronchitis (CB), bronchiectasis, emphysema, and reversible airway disease that combine uniquely in an individual patient. Older patients are at risk for COPD and its components—emphysema, CB, and bronchiectasis. Bacterial and viral infections play a role in acute exacerbations of COPD (AECOPD) and in acute exacerbations of CB (AECB) without features of COPD. Older patients are at risk for resistant bacterial organisms during their episodes of AECOPD and AECB. Organisms include the more‐common bacteria implicated in AECOPD/AECB such as Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. Less‐common nonenteric, gram‐negative organisms including Pseudomonas aeruginosa, gram‐positive organisms including Staphylococcus aureus, and strains of nontuberculosis Mycobacteria are more often seen in AECOPD/AECB episodes involving elderly patients with frequent episodes of CB or those with bronchiectasis. Risk‐stratified antibiotic treatment guidelines appear useful for purulent episodes of AECOPD and episodes of AECB. These guidelines have not been prospectively validated for the general population and especially not for the elderly population. Using a risk‐stratification approach for elderly patients, first‐line antibiotics (e.g., amoxicillin, ampicillin, pivampicillin, trimethoprim/sulfamethoxazole, and doxycycline), with a more‐limited spectrum of antibacterial coverage, are used in patients who are likely to have a low probability of resistant organisms during AECOPD/AECB. Second‐line antibiotics (e.g., amoxicillin/clavulanic acid, second‐ or third‐generation cephalosporins, and respiratory fluoroquinolones) with a broader spectrum of coverage are reserved for patients with significant risk factors for resistant organisms and those who have failed initial antibiotic treatment.

Moxifloxacin: a respiratory fluoroquinolone

BACKGROUND

Respiratory quinolones are a class of antimicrobials with a high activity against most respiratory pathogens. Moxifloxacin is a fourth-generation fluoroquinolone that has been shown to be effective against Gram-positive, Gram-negative, and atypical strains, as well as multi-drug resistant Streptococcus pneumoniae.

OBJECTIVE

To review and update the clinical efficacy of moxifloxacin in the treatment of respiratory infections.

METHOD

To perform a systematic review of publications on the clinical efficacy of moxifloxacin in respiratory infections.

RESULTS

The clinical efficacy of moxifloxacin has been shown in controlled studies of community-acquired pneumonia, exacerbations of chronic bronchitis and acute bacterial rhinosinusitis. Moxifloxacin has demonstrated a faster resolution of symptoms in community-acquired pneumonia and exacerbations of chronic bronchitis patients compared with first-line therapy together with excellent eradication rates.

CONCLUSIONS

The use of moxifloxacin as first-line therapy for moderate to severe respiratory infections in the community and the hospital has been recognized in international guidelines.

Indicators of bacterial infection in patients with acute exacerbation of chronic bronchitis for application in clinical trials of antibacterial drugs

OBJECTIVES

This study examined the accuracy of: (a) patient symptoms; (b) microscopic examination of sputum purulence (>25 WBCs and <10 epithelial cells) and (c) microscopic examination of morphological bacterial cell types, in identifying bacterial infection in patients with an acute exacerbation of chronic bronchitis (AECB) for entry to clinical trials.

METHODS

Subjects had a worsening of at least two symptoms from: dyspnoea, sputum volume, and sputum purulence (Anthonisen Type 1 or 2 exacerbation). Sputum samples were collected from all subjects.

RESULTS

A total of 97 sputum samples were evaluated. Overall, 58 (60%) subjects were culture-positive; 22 of 29 (76%) subjects with Type 2 exacerbation had a bacterial pathogen isolated compared with 36 of 68 (53%) Type 1 subjects. This difference was not statistically significant. Microscopically purulent samples were found to be significantly more likely to be culture-positive than non-purulent samples. However, the sensitivity (60%) and specificity (67%); and the positive predictive value (73%) and negative predictive value (53%) observed, means that this is not an ideal predictive test for clinical trials. A semi-quantitative approach to Gram staining was identified as a potential indicator of bacterial infection. Sputum specimens with one bacterial cell type present at >10 cells per field, or more than one cell type present with at least one type at a concentration of >25 cells per field, had a high proportion (91%) of culture-positive specimens.

CONCLUSIONS

Symptoms alone are a poor indicator of bacterial infection. A semi-quantitative examination of a Gram-stained sputum preparation was the best indicator of bacterial infection. This finding may have relevance in the design of clinical trials of antibacterial drugs in AECB.

Real-life treatment of acute exacerbations of chronic bronchitis with moxifloxacin or macrolides: a comparative post-marketing surveillance study in general practice

OBJECTIVE

To compare the real-life treatment of acute exacerbations of chronic bronchitis (AECBs) using moxifloxacin tablets or one of the oral macrolides azithromycin, clarithromycin or roxithromycin in terms of symptom relief, time until improvement and cure, overall efficacy and tolerability.

METHODS

This prospective, non-interventional, multicentre study included out-patients with AECB whose last exacerbation was treated with a macrolide. The current AECB was treated either with moxifloxacin or with one of the macrolides azithromycin, clarithromycin or roxithromycin. Data were obtained on the patient's characteristics, disease and treatment history, the course of the current AECB including time to improvement and cure, and the final assessments of efficacy and tolerability. All adverse events were recorded in patients treated with moxifloxacin; for patients receiving macrolides, only drug-related adverse events were reported.

RESULTS

464 physicians treated 904 patients with moxifloxacin and 846 patients with one of the macrolides. Age, sex and body mass index were well matched between the two treatment groups. However, more moxifloxacin than macrolide patients presented with a generally bad condition (62.8% vs 48.6%). About 42% of patients in both groups had had chronic bronchitis for 1-5 years, and about 27% for 5-10 years. The mean number of AECBs in the previous 12 months was 2.7 and 2.6, respectively. Moxifloxacin was administered to most patients for 5 (43.8%) or 7 days (42.4%). Patients in the macrolide group were treated in most cases with clarithromycin 500 mg for 4-7 days, roxithromycin 300 mg for 6-7 days or azithromycin 500 mg for 3 days. Physicians assessed overall efficacy and tolerability as 'very good' or 'good' in 96.1% and 98.1%, respectively, of moxifloxacin-treated patients and in 67.5% and 91.7%, respectively, of macrolide-treated patients. The mean duration until improvement and cure of AECB was 3.2 days (+/- SD 1.5) and 6.2 days (+/- 2.6) in moxifloxacin-treated patients compared with 4.5 days (+/- 1.8) and 7.5 days (+/- 3.0) in macrolide-treated patients (p < 0.0001).

CONCLUSION

The results of this study conducted under real-life treatment conditions in patients with AECBs who were previously treated with a macrolide showed faster symptom relief and higher recovery rates with moxifloxacin compared with macrolides. The two treatment groups had comparably good safety and tolerability profiles.

Clinical Efficacy of Moxifloxacin in the Treatment of Exacerbations of Chronic Bronchitis: A Systematic Review and Meta-Analysis

OBJECTIVE

As the research undertaken to date on the efficacy of the new antibiotics in the treatment of exacerbations of chronic bronchitis has taken the form of trials designed to demonstrate equivalence, we have no data on the advantages associated with the use of these new drugs with greater bactericidal activity. Our objective was to compare the clinical efficacy of moxifloxacin to that of the antibiotic regimens routinely used to treat such exacerbations by a systematic review of the literature and a meta-analysis.

METHODS

A manual and electronic search was performed to identify all clinical trials carried out between January 1997 and July 2005 to compare moxifloxacin and the antibiotics that are currently the first line treatment for exacerbations of chronic bronchitis. Once it had been established that the designs of the trials included were acceptable, a meta-analysis of clinical outcomes was performed.

RESULTS

Of the 45 studies identified, 9 met the inclusion criteria. Of these, 5 were double-blind randomized trials and 4 were randomized open trials. The 9 trials comprised a total of 3905 patients. The aggregate standardized mean difference in clinical success rate was 1.5% (95% confidence interval, -0.4 to 3.4%). Bacterial eradication rates ranged from 68.4% to 96% for the standard regimens, and from 87.7% to 96% for moxifloxacin. No intergroup differences in the percentages of patients lost to follow-up were observed in any of the studies.

CONCLUSIONS

Although the trials reviewed were designed to demonstrate equivalence, meta-analysis revealed that the clinical success rate achieved with moxifloxacin tended to be higher than that obtained in the groups that received standard antibiotic treatment.

Antibiothérapie des exacerbations de bronchopneumopathie chronique obstructive : analyse critique des essais cliniques

OBJECTIVE

The authors had for aim to assess the role of antibiotics in acute exacerbations of chronic obstructive pulmonary disease (COPD).

METHODS

Comparative antibiotic trials were collected through systematic search on Medline data base--well-designed studies were selected.

RESULTS

Eight equivalence studies were selected. No clear difference between antibiotics was demonstrated. The shortest treatment was as effective as the longest.

CONCLUSION

No antibiotic has demonstrated its superiority. A new generation of antibiotic comparative trials for exacerbation of COPD is clearly needed.

Eradication of H. influenzae in AECB: A pooled analysis of moxifloxacin phase III trials compared with macrolide agents

Haemophilus influenzae is the most common bacterial pathogen associated with acute exacerbations of chronic bronchitis (AECB). This study determined the rate of bacterial eradication of H. influenzae during AECB treated with either macrolides or moxifloxacin. Adult AECB patients with H. influenzae were included in a pooled analysis of four double-blind, multicentre, randomised trials. Patients received either moxifloxacin (400 mg qd for 5-10 days) or macrolides (azithromycin 500 mg/250 mg qd for 5 days or clarithromycin 500 mg bid for 5-10 days). Bacterial eradication and clinical success were recorded at the test-of-cure visit (7-37 days post-therapy). Of 2555 patients in the intent-to-treat population, 910 were microbiologically valid and 292 (32%) had H. influenzae cultured at baseline. Bacterial eradication of H. influenzae was significantly higher with moxifloxacin vs. macrolide-treated patients (93.0% [133/143] vs. 73.2% [109/149], respectively, P = 0.001). Moxifloxacin also demonstrated higher eradication rates compared with azithromycin (96.8% vs. 84.6%, P = 0.019) and clarithromycin (90.1% vs. 64.2%, P = 0.001) analysed separately. Clinical success was 89.5% (128/143) for moxifloxacin vs. 85.2% (127/149) for the macrolide group (P = 0.278); similar results were found when moxifloxacin was compared individually with each macrolide. For patients with AECB due to H. influenzae, moxifloxacin provided superior bacterial eradication rates than macrolide therapy.

Chronic obstructive pulmonary disease: clinical signs and infections

Chronic obstructive pulmonary disease (COPD) is a pathological condition that involves excessive production of mucus, chronic cough and inflammatory changes leading to airway limitation. The most common cause of COPD is cigarette smoking. COPD can be categorized into either chronic bronchitis or emphysema; both conditions can be differentiated by age and the production of copious, tenacious sputum. Patients with COPD are susceptible to pulmonary infections of bacterial or viral origin. Nurses should be aware of the subtle differences in conditions and the usefulness of antibiotics in the treatment of acute bacterial exacerbations of chronic bronchitis.

[Antibiotics for acute exacerbations of chronic obstructive pulmonary disease (COPD)]

OBJECTIVE

This study had for aim to evaluate the rationale and indications for antibiotic treatment in acute exacerbations of COPD and to identify potential differences among various antibiotics available for the treatment of exacerbations in France.

METHODS

A search was performed in Medline and for references quoted in identified articles from 1995 to 2005. Open or blind randomized studies involving antibiotics available in France were reviewed.

RESULTS

About 50% of all exacerbations are related to bacterial infection. Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae are the main pathogens responsible for bacterial exacerbations. Pseudomonas aeruginosa and enterobacter spp are frequently found in patients with severe functional impairment. Increased purulence of sputum is associated with bacterial infection. Patients with severe functional impairment benefit the most from antibiotic treatment. Although new molecules have larger antibiotic spectrum and better pharmacological properties, the evidence supporting their use compared to standard therapy remains scarce.

CONCLUSIONS

Additional studies are needed to better identify the subset of patients benefiting from antibiotics and to determine whether new molecules produce significant improvement on relevant outcomes such as exacerbation free interval compared to standard therapy.

Pharmacokinetic and pharmacodynamic aspects of oral moxifloxacin 400 mg/day in elderly patients with acute exacerbation of chronic bronchitis

OBJECTIVE

To assess the pharmacokinetic and pharmacodynamic behaviour of moxifloxacin in 15 consecutive elderly patients with acute exacerbation of chronic bronchitis (AECB) treated with the fixed oral moxifloxacin 400 mg/day regimen with the intent of verifying which degree of exposure may be ensured by this standard regimen against AECB pathogens.

METHODS

This was an open-label, observational, pharmacokinetic-pharmacodynamic study. Blood samples were collected at steady state at appropriate intervals. Moxifloxacin plasma concentrations were analysed by means of high-performance liquid chromatography. Standard pharmacokinetic parameters and pharmacodynamic determinants (peak concentration [C(max)]/minimum inhibitory concentration [MIC], area under the plasma concentration-time curve during the 24-hour observational period [AUC(24)]/MIC, pharmacodynamic breakpoints [PDBPs]) were assessed.

RESULTS

The mean estimated pharmacokinetic parameters (C(max) 4.40 mg/L at 1.4 hours, AUC(24) 42.67 mg . h/L, elimination half-life 12.55 hours, total body clearance 0.16 L/h/kg) were generally similar to those observed in both young and elderly historic controls (except for higher-dose normalised C(max) and lower volume of distribution of the central compartment). Median C(max)/MIC and AUC(24)/MIC ratios for moxifloxacin in the fully assessable cases were, respectively, 67.5 and 823.9 against Streptococcus pneumoniae, 25 and 310.2 against Moraxella catharralis and 416.5 and 3647.5 against Haemophilus influenzae. Mean estimates of PDBP for achieving C(max)/MIC values of 12.2 and AUC(24)/MIC values of 125 were 0.36 and 0.35 mg/L, respectively.

CONCLUSION

In patients with AECB the pharmacokinetic behaviour of moxifloxacin is not significantly altered by aging processes. This is consistent with moxifloxacin being metabolised mainly by means of phase II hepatic reactions, the activity of which was shown not to decline with age. Both the pharmacokinetic and pharmacodynamic analyses suggest that moxifloxacin 400 mg/day may be a valid therapeutic approach in the treatment of AECB in the elderly. Of note, the unmodified pharmacokinetic behaviour with no need for age-related dosage adjustments combined with the once-daily administration favouring compliance and the low potential for drug-drug pharmacokinetic interactions in case of polytherapy, make moxifloxacin particularly attractive in the treatment of elderly subpopulations at a very high risk of AECB.

Moxifloxacin and azithromycin but not amoxicillin protect human respiratory epithelial cells against streptococcus pneumoniae in vitro when administered up to 6 hours after challenge

We determined the protective effect of moxifloxacin, azithromycin, and amoxicillin against Streptococcus pneumoniae infection of respiratory cells. Moxifloxacin and azithromycin effectively killed intracellular S. pneumoniae strains and protected respiratory epithelial cells significantly even when given 6 h after S. pneumoniae challenge. Amoxicillin was less effective.

Guide to selection of fluoroquinolones in patients with lower respiratory tract infections

Newer fluoroquinolones such as levofloxacin, moxifloxacin, gatifloxacin and gemifloxacin have several attributes that make them excellent choices for the therapy of lower respiratory tract infections. In particular, they have excellent intrinsic activity against Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and the atypical respiratory pathogens. Fluoroquinolones may be used as monotherapy to treat high-risk patients with acute exacerbation of chronic bronchitis, and for patients with community-acquired pneumonia requiring hospitalisation, but not admission to intensive care. Overall, the newer fluoroquinolones often achieve clinical cure rates in > or =90% of these patients. However, rates may be lower in hospital-acquired pneumonia, and this infection should be treated on the basis of anticipated organisms and evaluation of risk factors for specific pathogens such as Pseudomonas aeruginosa. In this setting, an antipseudomonal fluoroquinolone may be used in combination with an antipseudomonalbeta-lactam. Concerns are now being raised about the widespread use, and possibly misuse, of fluoroquinolones and the emergence of resistance among S. pneumoniae, Enterobacteriaceae and P. aeruginosa. A number of pharmacokinetic parameters such as the peak concentration of the antibacterial after a dose (C(max)), and the 24-hour area under the concentration-time curve (AUC24) and their relationship to pharmacodynamic parameters such as the minimum inhibitory and the mutant prevention concentrations (MIC and MPC, respectively) have been proposed to predict the effect of fluoroquinolones on bacterial killing and the emergence of resistance. Higher C(max)/MIC or AUC24/MIC and C(max)/MPC or AUC24/MPC ratios, either as a result of dose administration or the susceptibility of the organism, may lead to a better clinical outcome and decrease the emergence of resistance, respectively. Pharmacokinetic profiles that are optimised to target low-level resistant minor subpopulations of bacteria that often exist in infections may help preserve fluoroquinolones as a class. To this end, optimising the AUC24/MPC or C(max)/MPC ratios is important, particularly against S. pneumoniae, in the setting of lower respiratory tract infections. Agents such as moxifloxacin and gemifloxacin with high ratios against this organism are preferred, and agents such as ciprofloxacin with low ratios should be avoided. For agents such as levofloxacin and gatifloxacin, with intermediate ratios against S. pneumoniae, it may be worthwhile considering alternative dose administration strategies, such as using higher dosages, to eradicate low-level resistant variants. This must, of course, be balanced against the potential of toxicity. Innovative approaches to the use of fluoroquinolones are worth testing in further in vitro experiments as well as in clinical trials.

Moxifloxacin: a review of its use in the management of bacterial infections

Moxifloxacin (Avelox) is a fluoroquinolone antibacterial with a methoxy group in the C-8 position and a bulky C-7 side chain. Moxifloxacin is approved for use in the treatment of acute exacerbations of chronic bronchitis (AECB), community-acquired pneumonia (CAP), acute bacterial sinusitis and uncomplicated skin and skin structure infections (approved indications may differ between countries). Moxifloxacin has a broad spectrum of antibacterial activity, including activity against penicillin-resistant Streptococcus pneumoniae. It achieves good tissue penetration and has a convenient once-daily administration schedule, as well as being available in both intravenous and oral formulations in some markets. Moxifloxacin has good efficacy in the treatment of patients with AECB, CAP, acute bacterial sinusitis and uncomplicated skin and skin structure infections, and is generally well tolerated. Thus, moxifloxacin is an important option in the treatment of bacterial infections.