Short-course fluoroquinolone therapy in exacerbations of chronic bronchitis and COPD

Optimising antibiotic exposure by customising the duration of treatment for respiratory tract infections based on patient needs in primary care

Primary care antimicrobial stewardship programs have limited success in reducing antibiotic use, prompting the search for new strategies. Convincing general practitioners to resist antibiotic prescription amid uncertainty or patient demands usually poses a significant challenge. Despite common practice, standard durations for common infections lack support from clinical studies. Contrary to common belief, extending antibiotic treatment beyond the resolution of symptoms does not seem to prevent or reduce antimicrobial resistance. Shortening the duration of antibiotic therapy has shown to be effective in mitigating the spread of resistance, particularly in cases of pneumonia. Recent hospital randomised trials suggest that ending antibiotic courses by day three for most lower respiratory tract infections is effective and safe. While community studies are scarce, it is likely that these shorter, tailored courses to meet patients' needs would also be effective and safe in primary care. Therefore, primary care studies should investigate the outcomes of advising patients to discontinue antibiotic treatment upon symptom resolution. Implementing patient-centred, customised treatment durations, rather than fixed courses, is crucial for meeting individual patient needs.

Expanding the arsenal against pulmonary diseases using surface-functionalized polymeric micelles: breakthroughs and bottlenecks

Pulmonary diseases such as lung cancer, asthma and tuberculosis have remained one of the common challenges globally. Polymeric micelles (PMs) have emerged as an effective technique for achieving targeted drug delivery for a local as well as a systemic effect. These PMs encapsulate and protect hydrophobic drugs, increase pulmonary targeting, decrease side effects and enhance drug efficacy through the inhalation route. In the current review, emphasis has been placed on the different barriers encountered by the drugs given via the pulmonary route and the mechanism of PMs in achieving drug targeting. The applications of PMs in different pulmonary diseases have also been discussed in detail.

Are short courses of antibiotic therapy as effective as standard courses for COPD exacerbations? A systematic review and meta-analysis

BACKGROUND

The best duration of antibiotic treatment for chronic obstructive pulmonary disease (COPD) exacerbations is uncertain.

OBJECTIVE

To evaluate whether a short course of antibiotic therapy is as effective as the standard longer treatment for exacerbations of patients with COPD.

METHODS

We searched Pubmed/MEDLINE and trials in relevant systematic reviews from the inception up to March 2021, with no language restrictions. Randomised controlled trials comparing short-course antibiotic therapy (≤5 days) with standard antibiotic therapy (≥6 days) for exacerbations of patients aged ≥40 with spirometrically-confirmed COPD were included. Three outcomes were considered: end-of-therapy clinical cure, bacterial eradication and adverse events. Statistical analyses included random effects meta-analyses using odds ratios and assessment of heterogeneity.

RESULTS

Of 1274 citations found, eight were eligible for inclusion, seven of which recruited outpatients. Overall, short-course antibiotic treatments were not significantly different from those of long-course treatments for clinical cure (odds ratio [OR] 1.14, 95% CI 0.91; 1.44) and for bacterial eradication (OR 1.16, 95% CI 0.91; 1.48). Adverse events were observed in 379 (21.1%) patients receiving short-term antibiotic regimens, while 412 (22.8%) patients receiving the standard regimens reported adverse events (OR 0.83, 95% CI 0.62; 1.11). The heterogeneity of the studies was low.

CONCLUSION

In relation to clinical and bacteriological efficacy, a short course of antibiotic treatment is equivalent to longer conventional treatment in mainly outpatients with exacerbations of COPD. Moreover, shorter exposure to antibiotics may decrease the risk developing antimicrobial resistance and, hence, might become first-line therapy for the management of ambulatory COPD patients.

Two-day versus seven-day course of levofloxacin in acute COPD exacerbation: a randomized controlled trial

INTRODUCTION

Duration of antibiotic treatment in acute exacerbation of COPD (AECOPD) is most commonly based on expert opinion. Typical administration periods range from 5 to 7 days. A 2-day course with levofloxacin was not previously assessed. We performed a randomized clinical trial to evaluate the efficacy of 2-day versus 7-day treatment with levofloxacin in patients with AECOPD.

METHODS AND ANALYSIS

Patients with AECOPD were randomized to receive levofloxacin for 2 days and 5 days placebo (n = 155) or levofloxacin for 7 days (n = 155). All patients received a common dose of intravenous prednisone daily for 5 days. The primary outcome measure was cure rate, and secondary outcomes included need for additional antibiotics, ICU admission rate, re-exacerbation rate, death rate, and exacerbation-free interval (EFI) within 1-year follow-up. The study protocol has been prepared in accordance with the revised Helsinki Declaration for Biomedical Research Involving Human Subjects and Guidelines for Good Clinical Practice. The study was approved by ethics committees of all participating centers prior to implementation (Monastir and Sousse Universities).

RESULTS

310 patients were randomized to receive 2-day course of levofloxacin (n = 155) or 7-day course (n = 155). Cure rate was 79.3% (n = 123) and 74.2% (n = 115), respectively, in 2-day and 7-day groups [OR 1.3; 95% CI 0.78-2.2 (p = 0.28)]. Need for additional antibiotics rate was 3.2% and 1.9% in the 2-day group and 7-day group, respectively; (p = 0.43). ICU admission rate was not significantly different between both groups. One-year re-exacerbation rate was 34.8% (n = 54) in 2-day group versus 29% (n = 45) in 7-day group (p = 0.19); the EFI was 121 days (interquartile range, 99-149) versus 110 days (interquartile range, 89-132) in 2-day and 7-day treatment groups, respectively; (p = 0.73). One-year death rate was not significantly different between the 2 groups, 5.2% versus 7.1% in the 2-day group and 7-day group, respectively; (p = 0.26). No difference in adverse effects was detected.

CONCLUSION

Levofloxacin once daily for 2 days is not inferior to 7 days with respect to cure rate, need for additional antibiotics and hospital readmission in AECOPD. Our findings would improve patient compliance and reduce the incidence of bacterial resistance and adverse effects.

2-Day versus C-reactive protein guided antibiotherapy with levofloxacin in acute COPD exacerbation: A randomized controlled trial

INTRODUCTION

Duration of antibiotic treatment in acute exacerbation of COPD (AECOPD) is most commonly based on expert opinion. Biomarker guided strategy is increasingly recommended to limit unnecessary antibiotic use. We performed a randomized controlled study to evaluate the efficacy of 2-day versus C-reactive protein (CRP)-guided treatment with levofloxacin in patients with AECOPD.

METHODS

Patients with AECOPD were randomized to receive oral levofloxacin daily for 7 days unless the serum CRP level decreased by at least 50% from the baseline value or levofloxacin for two days; thereafter, oral placebo tablet was prescribed according to the CRP. The primary outcome measure was cure rate, and secondary outcome included need for additional antibiotics, intensive care unit (ICU) admission, exacerbation rates and exacerbation free interval (EFI) within one-year follow-up.

RESULTS

In intention to treat (ITT) analysis, cure rate was 76.1% (n = 118) and 79.3% (n = 123) respectively in 2-day and CRP-guided groups. In per protocol (PP) analysis, cure rate was 73% (n = 92) and 70.4% (n = 88) respectively in 2-day and CRP-guided groups. The difference between the two groups was not significant. The need for additional antibiotics and ICU admission rates were not significantly different between the two groups. One-year exacerbation rate was 27% (n = 42) in 2-day group versus 30.3% (n = 47) in CRP-guided group (p = 0.53); the EFI was 125 days (interquartile range, 100-151) versus 100 days (interquartile range, 78-123) in 2-day and CRP-guided groups respectively (p = 0.45). No difference in adverse effects was detected.

CONCLUSION

Levofloxacin once daily for 2 days had similar efficacy compared to CRP-guided in AECOPD. This short course treatment decreased antibiotic consumption which would improve patient compliance and reduce adverse effects.

In vitro killing of canine strains of Staphylococcus pseudintermedius and Escherichia coli by cefazolin, cefovecin, doxycycline and pradofloxacin over a range of bacterial densities

Background

Bacterial densities likely fluctuate during infection and may exceed the bacterial density used in susceptibility testing. As such, investigation of bacterial killing by antibiotics over a range of varying bacterial densities may provide important differences between compounds and could impact drug selection for therapy.

Hypothesis/Objectives

To measure killing of clinical isolates of Staphylococcus pseudintermedius and Escherichia coli by cefazolin, cefovecin, doxycycline and pradofloxacin at clinically relevant (minimum inhibitory, mutant prevention, maximum serum and maximum tissue) drug concentrations against varying densities of bacteria.

Animals/Materials

Bacterial strains collected from dogs with urinary tract infections were studied.

Methods and materials

High bacterial densities ranging from 10⁶ to 10⁹ colony forming units (cfu)/mL were exposed to minimum inhibitory, mutant prevention, blood and tissue drug concentrations, and the percentages (log₁₀) of viable cells killed following 30 min, 1, 2, 4, 6, 12 and 24 h of drug exposure were quantified.

Results

Doxycycline exhibited bacteriostatic properties with less killing than the other three agents. For example, at a 10⁷ cfu/mL density of S. pseudintermedius, more cells were killed by pradofloxacin (P < 0.0001) and cefovecin (P = 0.0014) but not cefazolin when compared to doxycycline at the maximum serum drug concentration following 12 h of drug exposure.

Conclusions and clinical importance

Differences were seen between some drugs in the speed and extent of bacterial killing; this could be clinically important and may impact drug selection and length of therapy.

Background – Bacterial densities likely fluctuate during infection and may exceed the bacterial density used in susceptibility testing. As such, investigation of bacterial killing by antibiotics over a range of varying bacterial densities may provide important differences between compounds and could impact drug selection for therapy. Hypothesis – To measure killing of clinical isolates of Staphylococcus pseudintermedius and Escherichia coli by cefazolin, cefovecin, doxycycline and pradofloxacin at clinically relevant (minimum inhibitory, mutant prevention, maximum serum and maximum tissue) drug concentrations against varying densities of bacteria. Conclusions and clinical importance – Differences were seen between some drugs in the speed and extent of bacterial killing; this could be clinically important and may impact drug selection and length of therapy.

Comparative Effectiveness Of Fluoroquinolone Antibiotic Use In Uncomplicated Acute Exacerbations Of COPD: A Multi-Cohort Study

Purpose

Fluoroquinolone antibiotics are associated with rare, but severe adverse events. They are frequently used for the treatment of acute exacerbations of COPD (AECOPD). While their effectiveness in severe exacerbations requiring hospitalisation has been well documented, the potential benefit in the ambulatory setting is less clear, especially in uncomplicated patients with COPD.

Patients and characteristics

We carried out a retrospective cohort study using health care databases from six Canadian provinces in subjects visiting their physician for uncomplicated COPD. Subjects dispensed either a quinolone or other antibiotics were compared using inverse probability of treatment weights with high dimensional propensity scores on 30-day outcomes, including repeat visits, hospitalisation for AECOPD and subsequent antibiotic prescription. Results from each province were combined by random effects meta-analysis.

Results

We identified 286,866 AECOPD events among 203,642 unique individuals. The frequency of fluoroquinolone use, mostly levofloxacin and moxifloxacin, varied by province and ranged from 8% to 32% of AECOPD antibiotic prescriptions. The risk of a repeat ambulatory care visit was increased among patients who were dispensed a fluoroquinolone compared with other antibiotics (OR 1.32, 95% CI 1.27-1.36). The risk of a hospitalisation for AECOPD was also higher with fluoroquinolones (OR 1.52, 95% CI 1.33-1.74). There was no difference in subsequent antibiotic prescriptions (OR 1.00, 95% CI 0.94-1.07).

Conclusion

There is no apparent benefit in short-term outcomes with fluoroquinolones as compared to other antibiotics for the ambulatory treatment of AECOPD in uncomplicated patients. These findings support current recommendations that fluoroquinolones be reserved for AECOPD in patients with recurrent exacerbations, significant co-morbidity or requiring hospitalisation.

The effects of different enrofloxacin dosages on clinical efficacy and resistance development in chickens experimentally infected with Salmonella Typhimurium

To investigate the optimal dosage which can improve clinical efficacy and minimize resistance, pharmacokinetics/pharmacodynamics model of enrofloxacin was established. Effect of enrofloxacin treatments on clearance of Salmonella in experimentally infected chickens and simultaneously resistance selection in Salmonella and coliforms were evaluated in three treatment groups (100, PK/PD designed dosage of 4, 0.1 mg/kg b.w.) and a control group. Treatment duration was three rounds of 7-day treatment alternated with 7-day withdrawal. Results showed that 100 mg/kg b.w. of enrofloxacin completely eradicated Salmonella, but resistant coliforms (4.0-60.8%) were selected from the end of the second round's withdrawal period till the end of the experiment (days 28-42). PK/PD based dosage (4 mg/kg b.w.) effectively reduced Salmonella for the first treatment duration. However upon cessation of medication, Salmonella repopulated chickens and persisted till the end with reduced susceptibility (MICCIP = 0.03-0.25 mg/L). Low frequency (5-9.5%) of resistant coliforms was selected (days 39-42). Enrofloxacin at dosage of 0.1 mg/kg b.w. was not able to eliminate Salmonella and selected coliforms with slight decreased susceptibility (MICENR = 0.25 mg/L). In conclusion, short time treatment (7 days) of enrofloxacin at high dosage (100 mg/kg b.w.) could be effective in treating Salmonella infection while minimizing resistance selection in both Salmonella and coliforms.

Chronic Respiratory Infection in Patients with Chronic Obstructive Pulmonary Disease: What Is the Role of Antibiotics?

Chronic infections are associated with exacerbation in patients with chronic obstructive pulmonary disease (COPD). The major objective of the management of these patients is the prevention and effective treatment of exacerbations. Patients that have increased sputum production, associated with purulence and worsening shortness of breath, are the ones that will benefit from antibiotic therapy. It is important to give the appropriate antibiotic therapy to prevent treatment failure, relapse, and the emergence of resistant pathogens. In some patients, systemic corticosteroids are also indicated to improve symptoms. In order to identify which patients are more likely to benefit from these therapies, clinical guidelines recommend stratifying patients based on their risk factor associated with poor outcome or recurrence. It has been identified that patients with more severe disease, recurrent infection and presence of purulent sputum are the ones that will be more likely to benefit from this therapy. Another approach related to disease prevention could be the use of prophylactic antibiotics during steady state condition. Some studies have evaluated the continuous or the intermittent use of antibiotics in order to prevent exacerbations. Due to increased bacterial resistance to antibiotics and the presence of side effects, several antibiotics have been developed to be nebulized for both treatment and prevention of acute exacerbations. There is a need to design long-term studies to evaluate these interventions in the natural history of the disease. The purpose of this publication is to review our understanding of the role of bacterial infection in patients with COPD exacerbation, the role of antibiotics, and future interventions.

Pharmacotherapy for lower respiratory tract infections

INTRODUCTION

Bacterial infections play an important role as etiological agents in acute exacerbations of chronic obstructive pulmonary disease (AECOPD), and exacerbations of non-cystic fibrosis (CF) bronchiectasis. In acute bronchitis and asthma exacerbations their role is less well defined than with patients with COPD. The clinical features, causative pathogens and therapies of common acute respiratory tract infections are detailed in this review.

AREAS COVERED

This article covers medical literature published in any language from 2000 to 2014, on 'lower respiratory tract infections', identified using PubMed, MEDLINE and ClinicalTrial.gov. The search terms used were 'COPD exacerbations', 'bronchiectasis', 'macrolides' and 'inhaled antibiotics'.

EXPERT OPINION

Given that almost half of AECOPD are caused by bacteria, administration of antibacterial agents is recommended for patients with severe exacerbations or severe underlying COPD. Chronic prophylactic use of macrolides seems to be of benefit, particularly in patients with bronchiectasis and chronic mucous hypersecretion. In an effort to manage chronic airway infection non-CF bronchiectasis due to drug-resistant pathogens, aerosolized antibiotics may be of value, and the data from recent studies are examined to demonstrate the potential value of this therapy, which is often used as an adjunctive measure to systemic antimicrobial therapy.

Antibiotics for acute and chronic respiratory infection in patients with chronic obstructive pulmonary disease

Prevention and effective treatment of exacerbations are major objectives in the management of patients with chronic obstructive pulmonary disease (COPD). Antibiotics are mainstay treatment for patients with severe COPD with an acute exacerbation that includes increased sputum purulence and worsening shortness of breath. Although such treatment is associated with clinical benefit, treatment failure and relapse rates may be high, particularly in cases of inadequate antibiotic therapy through incomplete resolution of the initial exacerbation and persistent bacterial infection. These aspects have led to recommendations for a stratified approach to antibiotic therapy based on patient characteristics associated with increased risk factors for failure. Patients at greatest risk for poor outcome (i.e., those with severe COPD) are likely to derive greatest benefit from early treatment with antibiotics. Long-term or intermittent antibiotic treatment has been shown to prevent COPD exacerbations and hospitalizations. These effects may be achieved by reducing bacterial load in the airways in stable state and/or bronchial inflammation. Although systemic antibiotics are likely to remain the core treatment for patients with moderate to severe exacerbated COPD, inhaled antibiotics may represent a more optimal approach for the treatment and prevention of COPD exacerbations in the future. Regardless of the route of administration, further studies are required to evaluate the potential long-term adverse events of antibiotics and the development of bacterial resistance.

Clinical outcomes and cost analysis of exacerbations in chronic obstructive pulmonary disease

BACKGROUND

Exacerbations are a major cause of disability, hospital admissions, and increased healthcare costs in patients with chronic obstructive pulmonary disease (COPD). This study investigated the clinical outcomes of outpatients with moderate to severe exacerbated COPD and their related costs.

METHODS

An observational study on the outcomes of ambulatory exacerbations of COPD was conducted. The course of the exacerbation was evaluated at a follow-up visit at 4 weeks. A cost analysis that encompassed the use of healthcare resources for treatment of the exacerbation was performed.

RESULTS

A total of 260 patients were included, with a mean age of 68.3 years and a mean FEV1 (% predicted) of 58.9 %. Twenty-two percent of patients had significant cardiovascular comorbidity. The most frequently prescribed antibiotics were moxifloxacin in 137 cases and amoxicillin-clavulanate in 50 cases. The rate of failure at 4 weeks was 12.5 %, with no differences between the two most prescribed antibiotics; however, patients treated with moxifloxacin had symptoms for 1.9 fewer days (P = 0.01). The mean cost of the exacerbation was <euro>344.96 (95 % CI: <euro>48.55-<euro>641.78), with 9.6 % of the costs for drugs and 72.9 % for hospital care of patients for whom treatment had failed.

CONCLUSIONS

Antibiotic treatment of our population was in compliance with local guidelines. The rate of failure observed in our study was lower than that reported in previous studies; however, the small percentage of patients that required hospital attention generated almost two-thirds of the total costs of the exacerbations.

Identifying patients at risk of late recovery (≥ 8 days) from acute exacerbation of chronic bronchitis and COPD

OBJECTIVES

To identify factors associated with late recovery (≥ 8 days from exacerbation start) in patients with acute exacerbations of chronic bronchitis/COPD (AECB/AECOPD).

METHODS

An international, observational, non-interventional study in outpatients with AECB/AECOPD who received treatment for their exacerbation with the antibiotic moxifloxacin. Factors analyzed for late recovery included patient demographic characteristics, geographic region and disease severity. Additionally, logistic regression analysis was undertaken to identify factors associated with late recovery.

RESULTS

The analysis population was 40,435 patients aged ≥ 35 years, from Asia-Pacific, Europe, the Americas and Middle East/Africa. Most were male (63.1%), mean age 60.4 years and current or ex-smokers (60.6%) with history of ≥ 2 exacerbations in the previous year. Patients who underwent spirometry (n = 6408, 19.7%) had moderate airflow obstruction (mean FEV(1) 1.7 L). Both clinicians and patients reported that moxifloxacin provided clinical improvement in a mean of 3 days and recovery in 6 days. Clinical factors significantly associated with late recovery were: age ≥ 65 years, duration of chronic bronchitis >10 years, cardiac comorbidity, >3 exacerbations in the previous 12 months, current exacerbation type (Anthonisen I/II) and hospitalization in the last 12 months.

CONCLUSIONS

In a large cohort of patients, all treated with the same antibiotic for an exacerbation of chronic bronchitis or COPD, the main factors associated with late recovery (≥ 8 days) were: older age, history of frequent exacerbations, current exacerbation type of Anthonisen I/II, history of prior hospitalizations and cardiac comorbid conditions.