An 18-month study of the safety and efficacy of repeated courses of inhaled aztreonam lysine in cystic fibrosis

A multi-centre, tolerability study of a cannabidiol-enriched Cannabis Herbal Extract for chronic headaches in adolescents: The CAN-CHA protocol

INTRODUCTION

Cannabis products have been used in the management of headaches in adults and may play a role in pediatric chronic pain. Canadian pediatricians report increasing use of cannabis for the management of chronic headaches, despite no well-controlled studies to inform its dosing, safety, and effectiveness. The aim of our clinical trial is to determine the dosing and safety of a Cannabidiol (CBD)-enriched Cannabis Herbal Extract (CHE) for the treatment of chronic headaches in adolescents.

METHODS AND ANALYSIS

Youth, parents, and an expert steering committee co-designed this tolerability study. Twenty adolescents (aged 14 to 17 years), with a chronic migraine diagnosis for more than 6 months that has not responded to other therapies will be enrolled into an open label, dose escalation study across three Canadian sites. Study participants will receive escalating doses of a CBD-enriched CHE (MPL-001 with a THC:CBD of 1:25), starting at 0.2-0.4 mg/kg of CBD per day and escalating monthly up to 0.8-1.0 mg/kg of CBD per day. The primary objective of this study is to determine the safety and tolerability of CBD-enriched CHE in adolescents with chronic migraine. Secondary objectives of this study will inform the development of subsequent randomized controlled trials and include investigating the relationship between the dose escalation and change in the frequency of headache, impact and intensity of pain, changes in sleep, mood, function, and quality of life. Exploratory outcomes include investigating steady-state trough plasma levels of bioactive cannabinoids and investigating how pharmacogenetic profiles affect cannabinoid metabolism among adolescents receiving CBD-enriched CHE.

DISCUSSION

This protocol was co-designed with youth and describes a tolerability clinical trial of CBD-enriched CHE in adolescents with chronic headaches that have not responded to conventional therapies. This study is the first clinical trial on cannabis products in adolescents with chronic headaches and will inform the development of future comparative effectiveness clinical trials.

TRIAL REGISTRATION

CAN-CHA trial is registered with ClinicalTrials.gov with a number of register NCT05337033.

Beyond antibiotics: Emerging antivirulence strategies to combat Pseudomonas aeruginosa in cystic fibrosis

Pseudomonas aeruginosa is an opportunistic pathogen that poses a significant threat to individuals suffering from cystic fibrosis (CF). The pathogen is highly prevalent in CF individuals and is responsible for chronic infection, resulting in severe tissue damage and poor patient outcome. Prolonged antibiotic administration has led to the emergence of multidrug resistance in P. aeruginosa. In this direction, antivirulence strategies achieving targeted inhibition of bacterial virulence pathways, including quorum sensing, efflux pumps, lectins, and iron chelators, have been explored against CF isolates of P. aeruginosa. Hence, this review article presents a bird's eye view on the pulmonary infections involving P. aeruginosa in CF patients by laying emphasis on factors contributing to bacterial colonization, persistence, and disease progression along with the current line of therapeutics against P. aeruginosa in CF. We further collate scientific literature and discusses various antivirulence strategies that have been tested against P. aeruginosa isolates from CF patients.

Development and preliminary validation of the challenges of living with cystic fibrosis (CLCF) questionnaire: a 46-item measure of treatment burden for parent/carers of children with CF

OBJECTIVE

Treatments for cystic fibrosis (CF) are complex, labour-intensive, and perceived as highly burdensome by caregivers of children with CF. An instrument assessing burden of care is needed.

DESIGN

A stepwise, qualitative design was used to create the CLCF with caregiver focus groups, participant researchers, a multidisciplinary professional panel, and cognitive interviews.

MAIN OUTCOME MEASURES

Preliminary psychometric analyses evaluated the reliability and convergent validity of the CLCF scores. Cronbach's alpha assessed internal consistency and t-tests examined test-retest reliability. Correlations measured convergence between the Treatment Burden scale of the Cystic Fibrosis Questionnaire-Revised (CFQ-R) and the CLCF. Discriminant validity was assessed by comparing CLCF scores in one vs two-parent families, across ages, and in children with vs without Pseudomonas aeruginosa (PA).

RESULTS

Six Challenge subscales emerged from the qualitative data and the professional panel constructed a scoresheet estimating the Time and Effort required for treatments. Internal consistency and test-retest reliability were adequate. Good convergence was found between the Total Challenge score and Treatment Burden on the CFQ-R (r=-0.49, p = 0.02, n = 31). A recent PA infection signalled higher Total Challenge for caregivers (F(23)11.72, p = 0.002).

CONCLUSIONS

The CLCF, developed in partnership with parents/caregivers and CF professionals, is a timely, disease-specific burden measure for clinical research.

Antibiotic strategies for eradicating Pseudomonas aeruginosa in people with cystic fibrosis

BACKGROUND

Respiratory tract infections with Pseudomonas aeruginosa occur in most people with cystic fibrosis (CF). Established chronic P aeruginosa infection is virtually impossible to eradicate and is associated with increased mortality and morbidity. Early infection may be easier to eradicate. This is an updated review.

OBJECTIVES

Does giving antibiotics for P aeruginosa infection in people with CF at the time of new isolation improve clinical outcomes (e.g. mortality, quality of life and morbidity), eradicate P aeruginosa infection, and delay the onset of chronic infection, but without adverse effects, compared to usual treatment or an alternative antibiotic regimen? We also assessed cost-effectiveness.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and conference proceedings. Latest search: 24 March 2022. We searched ongoing trials registries. Latest search: 6 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of people with CF, in whom P aeruginosa had recently been isolated from respiratory secretions. We compared combinations of inhaled, oral or intravenous (IV) antibiotics with placebo, usual treatment or other antibiotic combinations. We excluded non-randomised trials and cross-over trials.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, assessed risk of bias and extracted data. We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 11 trials (1449 participants) lasting between 28 days and 27 months; some had few participants and most had relatively short follow-up periods. Antibiotics in this review are: oral - ciprofloxacin and azithromycin; inhaled - tobramycin nebuliser solution for inhalation (TNS), aztreonam lysine (AZLI) and colistin; IV - ceftazidime and tobramycin. There was generally a low risk of bias from missing data. In most trials it was difficult to blind participants and clinicians to treatment. Two trials were supported by the manufacturers of the antibiotic used. TNS versus placebo TNS may improve eradication; fewer participants were still positive for P aeruginosa at one month (odds ratio (OR) 0.06, 95% confidence interval (CI) 0.02 to 0.18; 3 trials, 89 participants; low-certainty evidence) and two months (OR 0.15, 95% CI 0.03 to 0.65; 2 trials, 38 participants). We are uncertain whether the odds of a positive culture decrease at 12 months (OR 0.02, 95% CI 0.00 to 0.67; 1 trial, 12 participants). TNS (28 days) versus TNS (56 days) One trial (88 participants) comparing 28 days to 56 days TNS treatment found duration of treatment may make little or no difference in time to next isolation (hazard ratio (HR) 0.81, 95% CI 0.37 to 1.76; low-certainty evidence). Cycled TNS versus culture-based TNS One trial (304 children, one to 12 years old) compared cycled TNS to culture-based therapy and also ciprofloxacin to placebo. We found moderate-certainty evidence of an effect favouring cycled TNS therapy (OR 0.51, 95% CI 0.31 to 0.82), although the trial publication reported age-adjusted OR and no difference between groups. Ciprofloxacin versus placebo added to cycled and culture-based TNS therapy One trial (296 participants) examined the effect of adding ciprofloxacin versus placebo to cycled and culture-based TNS therapy. There is probably no difference between ciprofloxacin and placebo in eradicating P aeruginosa (OR 0.89, 95% CI 0.55 to 1.44; moderate-certainty evidence). Ciprofloxacin and colistin versus TNS We are uncertain whether there is any difference between groups in eradication of P aeruginosa at up to six months (OR 0.43, 95% CI 0.15 to 1.23; 1 trial, 58 participants) or up to 24 months (OR 0.76, 95% CI 0.24 to 2.42; 1 trial, 47 participants); there was a low rate of short-term eradication in both groups. Ciprofloxacin plus colistin versus ciprofloxacin plus TNS One trial (223 participants) found there may be no difference in positive respiratory cultures at 16 months between ciprofloxacin with colistin versus TNS with ciprofloxacin (OR 1.28, 95% CI 0.72 to 2.29; low-certainty evidence). TNS plus azithromycin compared to TNS plus oral placebo Adding azithromycin may make no difference to the number of participants eradicating P aeruginosa after a three-month treatment phase (risk ratio (RR) 1.01, 95% CI 0.75 to 1.35; 1 trial, 91 participants; low-certainty evidence); there was also no evidence of any difference in the time to recurrence. Ciprofloxacin and colistin versus no treatment A single trial only reported one of our planned outcomes; there were no adverse effects in either group. AZLI for 14 days plus placebo for 14 days compared to AZLI for 28 days We are uncertain whether giving 14 or 28 days of AZLI makes any difference to the proportion of participants having a negative respiratory culture at 28 days (mean difference (MD) -7.50, 95% CI -24.80 to 9.80; 1 trial, 139 participants; very low-certainty evidence). Ceftazidime with IV tobramycin compared with ciprofloxacin (both regimens in conjunction with three months colistin) IV ceftazidime with tobramycin compared with ciprofloxacin may make little or no difference to eradication of P aeruginosa at three months, sustained to 15 months, provided that inhaled antibiotics are also used (RR 0.84, 95 % CI 0.65 to 1.09; P = 0.18; 1 trial, 255 participants; high-certainty evidence). The results do not support using IV antibiotics over oral therapy to eradicate P aeruginosa, based on both eradication rate and financial cost.

AUTHORS' CONCLUSIONS

We found that nebulised antibiotics, alone or with oral antibiotics, were better than no treatment for early infection with P aeruginosa. Eradication may be sustained in the short term. There is insufficient evidence to determine whether these antibiotic strategies decrease mortality or morbidity, improve quality of life, or are associated with adverse effects compared to placebo or standard treatment. Four trials comparing two active treatments have failed to show differences in rates of eradication of P aeruginosa. One large trial showed that intravenous ceftazidime with tobramycin is not superior to oral ciprofloxacin when inhaled antibiotics are also used. There is still insufficient evidence to state which antibiotic strategy should be used for the eradication of early P aeruginosa infection in CF, but there is now evidence that intravenous therapy is not superior to oral antibiotics.

Antimicrobial Strategies for Cystic Fibrosis

Lung infection is the leading cause of death in cystic fibrosis (CF), and antimicrobial therapies are the backbone of infection management. While many different strategies may be applied, rigorous microbiological surveillance, intensive eradication therapy, and long-term maintenance therapy based on inhaled antibiotics may be considered the main strategy for infection control in individuals with CF. While most of the existing evidence is based on infection with Pseudomonas aeruginosa, other important pathogens causing lung inflammation and deterioration exist and should be treated despite the evidence gap. In this chapter, we describe the approaches to the antimicrobial treatment of the most important pathogens in CF and the evidence behind.

Lessons from other fields of medicine, Part 2: Cystic fibrosis

Cystic fibrosis (CF), first described in 1938, is a common, life-limiting monogenetic disease. The discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in 1989 was crucial in advancing our understanding of disease pathogenesis and paving the road for treatment aimed at the fundamental molecular defect. With the delineation of over 2000 variations in the CFTR gene, a sound understanding of the individual variations in cell biology, and electrophysiological abnormalities conferred by the most common defects propelled the advent of targeted disease-modifying therapeutics beginning in 2012. Since then, CF care has transformed beyond just symptomatic treatment to include a variety of small-molecule therapies that address the basic electrophysiologic defect and cause profound improvements in physiology, clinical manifestations, and long-term outcomes, designed to differentially address six genetic/molecular subtypes. This chapter illustrates the progress made toward how fundamental science and translational initiatives enabled personalized, mutation specific treatment. We highlight the importance of preclinical assays and mechanistically-driven development strategies that were coupled with sensitive biomarkers and a clinical trial cooperative to provide a platform for successful drug development. This convergence of academic and private partnerships, and formation of multidisciplinary care teams directed by evidence-based initiatives provide a seminal example of addressing the needs of individuals with a rare, but fatal genetic disease.

Role of inhaled antibiotics in the era of highly effective CFTR modulators

Recurrent and chronic bacterial infections are common in people with cystic fibrosis (CF) and contribute to lung function decline. Antibiotics are the mainstay in the treatment of exacerbations and chronic bacterial infection in CF. Inhaled antibiotics are effective in treating chronic respiratory bacterial infections and eradicating Pseudomonas aeruginosa from the respiratory tract, with limited systemic adverse effects. In the past decade, highly effective cystic fibrosis transmembrane conductance regulator (CFTR) modulators have become a new therapy that partially corrects/opens chloride transport in patients with selected CFTR mutations, restoring mucus hydration and improving mucociliary clearance. The recent triple CFTR modulator combination is approved for ∼80-90% of the CF population and significantly reduces pulmonary exacerbations and improves respiratory symptoms and lung function. CFTR modulators have shifted the focus from symptomatic treatment to personalised/precision medicine by targeting genotype-specific CFTR defects. While these are highly effective, they do not fully normalise lung physiology, stop inflammation or resolve chronic lung damage, such as bronchiectasis. The impact of these new drugs on lung health is likely to change the future management of chronic pulmonary infections in people with CF. This article reviews the role of inhaled antibiotics in the era of CFTR modulators.

Airway multidrug-resistant organisms in a population of tracheostomy and chronic ventilator-dependent children at a tertiary care pediatric hospital

OBJECTIVE/BACKGROUND

Children with tracheostomies are at an increased risk of bacterial respiratory tract infections. Infections caused by multidrug-resistant organisms (MDROs) are more difficult to treat and can result in severe complications. This study aimed to investigate the risk factors and sequelae of MDRO positivity in tracheostomy and chronic ventilator-dependent children.

METHODS

We performed a retrospective chart review of 75 tracheostomy and chronic ventilator-dependent children at St. Louis Children's Hospital. Data on demographics, respiratory cultures, hospitalizations, emergency department (ED) visits, and antibiotic usage were collected. We determined the frequency of MDRO positivity and compared the number of hospitalizations, number of ED visits, and antibiotic usage in patients with and without MDRO-positive cultures. Patient clinical variables were analyzed before and after MDRO acquisition.

RESULTS

We found 75.7% (56/74) of our participants had an MDRO-positive culture, with methicillin-resistant Staphylococcus aureus (MRSA, n = 36, 64%) and Pseudomonas aeruginosa (n = 8, 14%) being the most commonly detected organisms. Participants with a greater number of annual nonpulmonary admissions (odds ratio [OR] = 1.99, 95% confidence interval [CI] (1.21-3.29), p = 0.008], inpatient antibiotic courses [OR = 1.27, 95% CI (1.07-1.50), p = 0.006], total antibiotic courses [OR = 1.26, 95% CI (1.08-1.48), p = 0.004], and chronic antibiotic use [OR = 2.31, 95% CI (1.12-4.74), p = 0.03] were at an increased risk for MDRO positivity. Those who were MDRO-positive had more pulmonary admissions following MDRO acquisition compared those who were MDRO-negative [p = 0.005] but not more antibiotic usage or ED visits.

CONCLUSION

Frequent antibiotic usage and hospitalizations increase the risk of MDRO acquisition in children with tracheostomies and ventilator-dependence. Further antibiotic stewardship may help prevent resistant infections in technology-dependent children.

Role of Inhalational Aztreonam Lysine in Lower Airway Infections in Cystic Fibrosis: An Updated Literature Review

Cystic fibrosis (CF) is an inherited disorder most prevalent in the Caucasian population, characterized by a functional abnormality of the transmembrane conductance regulator protein that leads to a wide array of complications, including chronic lung infections. Pseudomonas aeruginosa (PA) is a frequently acquired microbe in CF patients and is associated with deterioration in pulmonary function and increased mortality. Inhaled anti-infective agents are an established curative therapy for CF airway infections, especially with chronic PA lung disease. Amongst them, aztreonam lysine for inhalation (AZLI) is an aerosolized monobactam antibiotic aztreonam, approved for use in CF patients nearly a decade ago. This literature review aims to explore studies based on the efficacy, safety, and tolerability of AZLI use in CF patients with pulmonary infections. We searched for all the relevant articles present in PubMed, Google Scholar, Cochrane Library, EMBASE, ClinicalTrials.gov, and Journal of Cystic Fibrosis for our data collection from 2000 to 2020. The use of AZLI has substantially improved lung function, respiratory symptoms, and remarkably reduced sputum PA density in CF patients, thereby improving the patient's overall quality of life. The adverse effects reported were compatible with CF lung disease. Hence, inhalational therapy with AZLI is highly efficacious and safe in the management of chronic airway infections. More clinical trials need to be conducted in the future to assess its long-term clinical benefits and adverse events as well as to explore the role of AZLI in the setting of acute lung infections.

The Elusive Role of Airway Infection in Cystic Fibrosis Exacerbation

Cystic fibrosis (CF) pulmonary exacerbations (PEx) are clinical events that commonly result in increased treatment burden, decreased quality of life, and accelerated lung disease progression. CF PEx have historically been approached as though dealing with acute infections, and antibiotic treatments have been associated with improved outcomes. In this review, we discuss data supporting a causal role of CF airway infection in PEx as well studies that highlight our knowledge gaps in regard to PEx definitions, pathophysiology, and optimal treatment approaches. In the era of highly effective cystic fibrosis transmembrane conductance regulator modulator therapy, and the continually increasing health and longevity of persons with CF, a better understanding of PEx and further optimization of PEx antibiotic treatment approaches are needed.

Antibiotherapy in Children with Cystic Fibrosis—An Extensive Review

In cystic fibrosis (CF), the respiratory disease is the main factor that influences the outcome and the prognosis of patients, bacterial infections being responsible for severe exacerbations. The etiology is often multi-microbial and with resistant strains. The aim of this paper is to present current existing antibiotherapy solutions for CF-associated infections in order to offer a reliable support for individual, targeted, and specific treatment. The inclusion criteria were studies about antibiotherapy in CF pediatric patients. Studies involving adult patients or those with only in vitro results were excluded. The information sources were all articles published until December 2021, in PubMed and ScienceDirect. A total of 74 studies were included, with a total number of 26,979 patients aged between 0–18 years. We approached each pathogen individual, with their specific treatment, comparing treatment solutions proposed by different studies. Preservation of lung function is the main goal of therapy in CF, because once parenchyma is lost, it cannot be recovered. Early personalized intervention and prevention of infection with reputable germs is of paramount importance, even if is an asymmetrical challenge. This research received no external funding.

Inhaled antibiotics for pulmonary exacerbations in cystic fibrosis

BACKGROUND

Cystic fibrosis is a genetic disorder in which abnormal mucus in the lungs is associated with susceptibility to persistent infection. Pulmonary exacerbations are when symptoms of infection become more severe. Antibiotics are an essential part of treatment for exacerbations and inhaled antibiotics may be used alone or in conjunction with oral antibiotics for milder exacerbations or with intravenous antibiotics for more severe infections. Inhaled antibiotics do not cause the same adverse effects as intravenous antibiotics and may prove an alternative in people with poor access to their veins. This is an update of a previously published review.

OBJECTIVES

To determine if treatment of pulmonary exacerbations with inhaled antibiotics in people with cystic fibrosis improves their quality of life, reduces time off school or work, and improves their long-term lung function.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Group's Cystic Fibrosis Trials Register. Date of the last search: 7 March 2022. We also searched ClinicalTrials.gov, the Australia and New Zealand Clinical Trials Registry and WHO ICTRP for relevant trials. Date of last search: 3 May 2022.

SELECTION CRITERIA

Randomised controlled trials in people with cystic fibrosis with a pulmonary exacerbation in whom treatment with inhaled antibiotics was compared to placebo, standard treatment or another inhaled antibiotic for between one and four weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible trials, assessed the risk of bias in each trial and extracted data. They assessed the certainty of the evidence using the GRADE criteria. Authors of the included trials were contacted for more information.

MAIN RESULTS

Five trials with 183 participants are included in the review. Two trials (77 participants) compared inhaled antibiotics alone to intravenous antibiotics alone and three trials (106 participants) compared a combination of inhaled and intravenous antibiotics to intravenous antibiotics alone. Trials were heterogenous in design and two were only available in abstract form. Risk of bias was difficult to assess in most trials but, for four out of five trials, we judged there to be a high risk from lack of blinding and an unclear risk with regards to randomisation. Results were not fully reported and only limited data were available for analysis. One trial was a cross-over design and we only included data from the first intervention arm. Inhaled antibiotics alone versus intravenous antibiotics alone Only one trial (18 participants) reported a perceived improvement in lifestyle (quality of life) in both groups (very low-certainty evidence). Neither trial reported on time off work or school. Both trials measured lung function, but there was no difference reported between treatment groups (very low-certainty evidence). With regards to our secondary outcomes, one trial (18 participants) reported no difference in the need for additional antibiotics and the second trial (59 participants) reported on the time to next exacerbation. In neither case was a difference between treatments identified (both very low-certainty evidence). The single trial (18 participants) measuring adverse events and sputum microbiology did not observe any in either treatment group for either outcome (very low-certainty  evidence). Inhaled antibiotics plus intravenous antibiotics versus intravenous antibiotics alone Inhaled antibiotics plus intravenous antibiotics may make little or no difference to quality of life compared to intravenous antibiotics alone. None of the trials reported time off work or school. All three trials measured lung function, but found no difference between groups in forced expiratory volume in one second (two trials; 44 participants; very low-certainty evidence) or vital capacity (one trial; 62 participants). None of the trials reported on the need for additional antibiotics. Inhaled plus intravenous antibiotics may make little difference to the time to next exacerbation; however, one trial (28 participants) reported on hospital admissions and found no difference between groups. There is likely no difference between groups in adverse events (very low-certainty evidence) and one trial (62 participants) reported no difference in the emergence of antibiotic-resistant organisms (very low-certainty evidence).

AUTHORS' CONCLUSIONS

We identified only low- or very low-certainty evidence to judge the effectiveness of inhaled antibiotics for the treatment of pulmonary exacerbations in people with cystic fibrosis. The included trials were not sufficiently powered to achieve their goals. Hence, we are unable to demonstrate whether one treatment was superior to the other or not. Further research is needed to establish whether inhaled tobramycin may be used as an alternative to intravenous tobramycin for some pulmonary exacerbations.

Indian Guidelines on Nebulization Therapy

Inhalational therapy, today, happens to be the mainstay of treatment in obstructive airway diseases (OADs), such as asthma, chronic obstructive pulmonary disease (COPD), and is also in the present, used in a variety of other pulmonary and even non-pulmonary disorders. Hand-held inhalation devices may often be difficult to use, particularly for children, elderly, debilitated or distressed patients. Nebulization therapy emerges as a good option in these cases besides being useful in the home care, emergency room and critical care settings. With so many advancements taking place in nebulizer technology; availability of a plethora of drug formulations for its use, and the widening scope of this therapy; medical practitioners, respiratory therapists, and other health care personnel face the challenge of choosing appropriate inhalation devices and drug formulations, besides their rational application and use in different clinical situations. Adequate maintenance of nebulizer equipment including their disinfection and storage are the other relevant issues requiring guidance. Injudicious and improper use of nebulizers and their poor maintenance can sometimes lead to serious health hazards, nosocomial infections, transmission of infection, and other adverse outcomes. Thus, it is imperative to have a proper national guideline on nebulization practices to bridge the knowledge gaps amongst various health care personnel involved in this practice. It will also serve as an educational and scientific resource for healthcare professionals, as well as promote future research by identifying neglected and ignored areas in this field. Such comprehensive guidelines on this subject have not been available in the country and the only available proper international guidelines were released in 1997 which have not been updated for a noticeably long period of over two decades, though many changes and advancements have taken place in this technology in the recent past. Much of nebulization practices in the present may not be evidence-based and even some of these, the way they are currently used, may be ineffective or even harmful. Recognizing the knowledge deficit and paucity of guidelines on the usage of nebulizers in various settings such as inpatient, out-patient, emergency room, critical care, and domiciliary use in India in a wide variety of indications to standardize nebulization practices and to address many other related issues; National College of Chest Physicians (India), commissioned a National task force consisting of eminent experts in the field of Pulmonary Medicine from different backgrounds and different parts of the country to review the available evidence from the medical literature on the scientific principles and clinical practices of nebulization therapy and to formulate evidence-based guidelines on it. The guideline is based on all possible literature that could be explored with the best available evidence and incorporating expert opinions. To support the guideline with high-quality evidence, a systematic search of the electronic databases was performed to identify the relevant studies, position papers, consensus reports, and recommendations published. Rating of the level of the quality of evidence and the strength of recommendation was done using the GRADE system. Six topics were identified, each given to one group of experts comprising of advisors, chairpersons, convenor and members, and such six groups (A-F) were formed and the consensus recommendations of each group was included as a section in the guidelines (Sections I to VI). The topics included were: A. Introduction, basic principles and technical aspects of nebulization, types of equipment, their choice, use, and maintenance B. Nebulization therapy in obstructive airway diseases C. Nebulization therapy in the intensive care unit D. Use of various drugs (other than bronchodilators and inhaled corticosteroids) by nebulized route and miscellaneous uses of nebulization therapy E. Domiciliary/Home/Maintenance nebulization therapy; public & health care workers education, and F. Nebulization therapy in COVID-19 pandemic and in patients of other contagious viral respiratory infections (included later considering the crisis created due to COVID-19 pandemic). Various issues in different sections have been discussed in the form of questions, followed by point-wise evidence statements based on the existing knowledge, and recommendations have been formulated.

Antibiotic resistance in chronic respiratory diseases: from susceptibility testing to the resistome

The development of resistome analysis, i.e. the comprehensive analysis of antibiotic-resistance genes (ARGs), is enabling a better understanding of the mechanisms of antibiotic-resistance emergence. The respiratory microbiome is a dynamic and interactive network of bacteria, with a set of ARGs that could influence the response to antibiotics. Viruses such as bacteriophages, potential carriers of ARGs, may also form part of this respiratory resistome. Chronic respiratory diseases (CRDs) such as cystic fibrosis, severe asthma, chronic obstructive pulmonary disease and bronchiectasis, managed with long-term antibiotic therapies, lead to multidrug resistance. Antibiotic susceptibility testing provides a partial view of the bacterial response to antibiotics in the complex lung environment. Assessing the ARG network would allow personalised, targeted therapeutic strategies and suitable antibiotic stewardship in CRDs, depending on individual resistome and microbiome signatures. This review summarises the influence of pulmonary antibiotic protocols on the respiratory microbiome, detailing the variable consequences according to antibiotic class and duration of treatment. The different resistome-profiling methods are explained to clarify their respective place in antibiotic-resistance analysis in the lungs. Finally, this review details current knowledge on the respiratory resistome related to therapeutic strategies and provides insight into the application of resistome analysis to counter the emergence of multidrug-resistant respiratory pathogens.

Inhaled Medicines: Past, Present, and Future

The purpose of this review is to summarize essential pharmacological, pharmaceutical, and clinical aspects in the field of orally inhaled therapies that may help scientists seeking to develop new products. After general comments on the rationale for inhaled therapies for respiratory disease, the focus is on products approved approximately over the last half a century. The organization of these sections reflects the key pharmacological categories. Products for asthma and chronic obstructive pulmonary disease include β -2 receptor agonists, muscarinic acetylcholine receptor antagonists, glucocorticosteroids, and cromones as well as their combinations. The antiviral and antibacterial inhaled products to treat respiratory tract infections are then presented. Two "mucoactive" products-dornase α and mannitol, which are both approved for patients with cystic fibrosis-are reviewed. These are followed by sections on inhaled prostacyclins for pulmonary arterial hypertension and the challenging field of aerosol surfactant inhalation delivery, especially for prematurely born infants on ventilation support. The approved products for systemic delivery via the lungs for diseases of the central nervous system and insulin for diabetes are also discussed. New technologies for drug delivery by inhalation are analyzed, with the emphasis on those that would likely yield significant improvements over the technologies in current use or would expand the range of drugs and diseases treatable by this route of administration. SIGNIFICANCE STATEMENT: This review of the key aspects of approved orally inhaled drug products for a variety of respiratory diseases and for systemic administration should be helpful in making judicious decisions about the development of new or improved inhaled drugs. These aspects include the choices of the active ingredients, formulations, delivery systems suitable for the target patient populations, and, to some extent, meaningful safety and efficacy endpoints in clinical trials.

Therapeutic Approach of Chronic Pseudomonas Infection in Cystic Fibrosis-A Network Meta-Analysis

Pseudomonas infection is a major determinant of morbidity and mortality in cystic fibrosis (CF). Maintaining optimal lung function in CF patients carrying Pseudomonas remains a challenge. Our study aims to investigate the efficacy of antipseudomonal inhaled antibiotics in CF patients with chronic Pseudomonas infection. A Bayesian network meta-analysis of randomized controlled trials was conducted. The main outcomes were changes in: (a) forced respiratory volume (FEV1), (b) Pseudomonas aeruginosa sputum density, and (c) CF Questionnaire Revised Respiratory Symptom Score (CFQR-RSS) at 4 weeks follow-up. Eighteen trials which reported on treatment with aztreonam lysine, tobramycin, colistin, levofloxacin, fosfomycin/tobramycin, and amikacin in various dosages were eligible for inclusion. In terms of change in FEV1%, aztreonam lysine (t.i.d., 75 mg) with a 28-day run in the tobramycin phase, aztreonam lysine (b.i.d., 75 mg) with a 28-day run in the tobramycin phase had the highest probability of being the most effective treatment (SUCRAs were 77, 76%, respectively). Regarding change in Pseudomonas sputum density, aztreonam lysine (b.i.d., 75 mg) with a 28-day run in the tobramycin phase, aztreonam lysine (t.i.d., 75 mg) with a 28-day run in the tobramycin phase had the highest probability of being the most effective treatment (SUCRAs were 90, 86%, respectively). Regarding change in CFQR-RSS, aztreonam lysine (t.i.d., 75 mg) and aztreonam lysine (b.i.d., 75 mg) with a 28-day run in the tobramycin inhalation solution phase had the highest probability of being the most effective treatments (SUCRA:74% and 72%, respectively). Regarding changes in FEV1% and Pseudomonas sputum density, aztreonam lysine with a run in tobramycin phase may be the best treatment option in treating chronic Pseudomonas in CF. According to CFQR-RSS no significant differences were found. Given the limitations of the studies included, validation trials are called for.

Long-term amikacin liposome inhalation suspension in cystic fibrosis patients with chronic P. aeruginosa infection

BACKGROUND

. In CLEAR-108-a phase 3, randomised, open-label study-once-daily amikacin liposome inhalation suspension (ALIS) was noninferior to twice-daily tobramycin inhalation solution (TIS) in improving lung function in patients with cystic fibrosis (CF) and chronic Pseudomonas aeruginosa infection after 3 treatment cycles (28 days on/28 days off). The CLEAR-110 extension study (ClinicalTrials.gov: NCT01316276; EudraCT: 2011-000443-24) assessed long-term safety, tolerability, and efficacy of ALIS in eligible patients who completed CLEAR-108.

METHODS

. Patients received once-daily ALIS 590 mg for 12 treatment cycles (96 weeks). Patients were grouped by prior treatment: the "prior-ALIS" cohort received ALIS in CLEAR-108, and the "ALIS-naive" cohort received TIS in CLEAR-108.

RESULTS

. Overall, 206 patients (prior-ALIS, n=92; ALIS-naive, n=114) entered CLEAR-110 and received ≥1 dose of ALIS. Most patients (88.8%) experienced ≥1 treatment-emergent adverse event (TEAE) through day 672 (end of year 2). Most TEAEs (72.3%) were mild or moderate in severity. Severe TEAEs were reported in 31 patients (15.0%). Two life-threatening TEAEs (haemoptysis; intestinal obstruction) and 1 death (cardiac failure) were reported. Twenty-one patients (10.2%) discontinued treatment due to a TEAE (mostly infective pulmonary exacerbation of CF). Mean change from baseline in forced expiratory volume in 1 second percent predicted at day 672 was -3.1% (prior-ALIS, -4.0%; ALIS-naive, -2.3%). Mean change from baseline in sputum density of P. aeruginosa at day 672 was 0.02 (prior-ALIS, -0.16; ALIS-naive, 0.19) log CFU/g.

CONCLUSIONS

. Long-term treatment with ALIS was well tolerated with a favourable adverse event profile and demonstrated continued antibacterial activity in CF patients with chronic P. aeruginosa infection.

Clinical impact of levofloxacin inhalation solution in cystic fibrosis patients in a real-world setting

BACKGROUND

Levofloxacin inhalation solution is the most recently approved inhaled antibiotic in Europe and Canada for adult cystic fibrosis patients. Its efficacy and safety have been assessed in randomized controlled trials. Our aim was to evaluate real life experience and outcomes in our treatment centre.

METHODS

We evaluated the efficacy of inhaled levofloxacin solution in 86 patients with cystic fibrosis in terms of the following outcome parameters: changes in %-predicted forced expiratory volume in one second (FEV₁), body-mass index (BMI), and exacerbation rate. We conducted an intraindividual analysis of patients who received levofloxacin inhalation solution twice daily 240 mg for at least 4 weeks.

RESULTS

Change in FEV₁% predicted for the treatment period was +2.27% (p=0.0027) after 4 weeks. There was no change in BMI for overall group, but exacerbation rate compared to one year before initiation of inhaled levofloxacin decreased significantly (p=0.0024) after 1 year of treatment (3.23 ± 1.39 versus 2.71 ± 1.58).

CONCLUSIONS

In patients with cystic fibrosis, inhaled levofloxacin solution has the potential to improve FEV₁ and to reduce the number of bronchopulmonary exacerbations.

Cystic Fibrosis: Recent Insights into Inhaled Antibiotic Treatment and Future Perspectives

Although new inhaled antibiotics have profoundly improved respiratory diseases in cystic fibrosis (CF) patients, lung infections are still the leading cause of death. Inhaled antibiotics, i.e., colistin, tobramycin, aztreonam lysine and levofloxacin, are used as maintenance treatment for CF patients after the development of chronic Pseudomonas aeruginosa (P. aeruginosa) infection. Their use offers advantages over systemic therapy since a relatively high concentration of the drug is delivered directly to the lung, thus, enhancing the pharmacokinetic/pharmacodynamic parameters and decreasing toxicity. Notably, alternating treatment with inhaled antibiotics represents an important strategy for improving patient outcomes. The prevalence of CF patients receiving continuous inhaled antibiotic regimens with different combinations of the anti-P. aeruginosa antibiotic class has been increasing over time. Moreover, these antimicrobial agents are also used for preventing acute pulmonary exacerbations in CF. In this review, the efficacy and safety of the currently available inhaled antibiotics for lung infection treatment in CF patients are discussed, with a particular focus on strategies for eradicating P. aeruginosa and other pathogens. Moreover, the effects of long-term inhaled antibiotic therapy for chronic P. aeruginosa infection and for the prevention of pulmonary exacerbations is reviewed. Finally, how the mucus environment and microbial community richness can influence the efficacy of aerosolized antimicrobial agents is discussed.

Standard versus biofilm antimicrobial susceptibility testing to guide antibiotic therapy in cystic fibrosis

BACKGROUND

Clinicians typically select the antibiotics used to treat pulmonary infections in people with cystic fibrosis based on the results of antimicrobial susceptibility testing performed on bacteria traditionally grown in a planktonic mode (grown in a liquid). However, there is considerable evidence to suggest that Pseudomonas aeruginosa actually grows in a biofilm (or slime layer) in the airways of people with cystic fibrosis with chronic pulmonary infections. Therefore, choosing antibiotics based on biofilm rather than conventional antimicrobial susceptibility testing could potentially improve response to treatment of Pseudomonas aeruginosa in people with cystic fibrosis. This is an update of a previously published Cochrane Review.

OBJECTIVES

To compare biofilm antimicrobial susceptibility testing-driven therapy to conventional antimicrobial susceptibility testing-driven therapy in the treatment of Pseudomonas aeruginosa infection in people with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Most recent search: 07 April 2020. We also searched two ongoing trials registries and the reference lists of relevant articles and reviews. Most recent searches: 07 April 2020 and 05 September 2017.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of antibiotic therapy based on biofilm antimicrobial susceptibility testing compared to antibiotic therapy based on conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infection in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently selected RCTs, assessed their risk of bias and extracted data from eligible trials. Additionally, the review authors contacted the trial investigators to obtain further information. The quality of the evidence was assessed using the GRADE criteria.

MAIN RESULTS

The searches identified two multicentre, double-blind RCTs eligible for inclusion in the review with a total of 78 participants (adults and children); one RCT was undertaken in people who were clinically stable, the second was in people experiencing pulmonary exacerbations. Both RCTs prospectively assessed whether the use of biofilm antimicrobial susceptibility testing improved microbiological and clinical outcomes in participants with cystic fibrosis who were infected with Pseudomonas aeruginosa. The primary outcome was the change in sputum Pseudomonas aeruginosa density from the beginning to the end of antibiotic therapy. Although the intervention was shown to be safe, the data from these two RCTs did not provide evidence that biofilm susceptibility testing was superior to conventional susceptibility testing either in terms of microbiological or lung function outcomes. One of the trials also measured risk and time to subsequent exacerbation as well as quality of life measures and did not demonstrate any difference between groups in these outcomes. Both RCTs had an overall low risk of bias and the quality of the evidence using GRADE criteria was deemed to be moderate to high for the outcomes selected.

AUTHORS' CONCLUSIONS

The current evidence is insufficient to recommend choosing antibiotics based on biofilm antimicrobial susceptibility testing rather than conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infections in people with cystic fibrosis. Biofilm antimicrobial susceptibility testing may be more appropriate in the development of newer, more effective formulations of drugs which can then be tested in clinical trials.

Combination antimicrobial susceptibility testing for acute exacerbations in chronic infection of Pseudomonas aeruginosa in cystic fibrosis

BACKGROUND

Antibiotic therapy for acute pulmonary exacerbations in people with cystic fibrosis is usually chosen based on the results of antimicrobial susceptibility testing of individual drugs. Combination antimicrobial susceptibility testing assesses the efficacy of drug combinations including two or three antibiotics in vitro and can often demonstrate antimicrobial efficacy against bacterial isolates even when individual antibiotics have little or no effect. Therefore, choosing antibiotics based on combination antimicrobial susceptibility testing could potentially improve response to treatment in people with cystic fibrosis with acute exacerbations. This is an updated version of a previously published review.

OBJECTIVES

To compare antibiotic therapy based on conventional antimicrobial susceptibility testing to antibiotic therapy based on combination antimicrobial susceptibility testing in the treatment of acute pulmonary exacerbations in people with cystic fibrosis and chronic infection with Pseudomonas aeruginosa.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Cystic Fibrosis Trials Register which comprises of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of latest search: 19 March 2020. We also searched ongoing trials registries. Date of latest search: 07 April 2020.

SELECTION CRITERIA

Randomised and quasi-randomised controlled studies of antibiotic therapy based on conventional antimicrobial susceptibility testing compared to antibiotic therapy based on combination antimicrobial susceptibility testing in the treatment of acute pulmonary exacerbations in cystic fibrosis due to chronic infection with Pseudomonas aeruginosa.

DATA COLLECTION AND ANALYSIS

Both authors independently selected studies, assessed their quality and extracted data from eligible studies. Additionally, the authors contacted the study investigators to obtain further information.

MAIN RESULTS

The search identified one multicentre study eligible for inclusion in the review. This study prospectively assessed whether the use of multiple combination bactericidal antibiotic testing improved clinical outcomes in participants with acute pulmonary exacerbations of cystic fibrosis who were infected with multiresistant bacteria. A total of 132 participants were randomised in the study. The study investigators provided data specific to the 82 participants who were only infected with Pseudomonas aeruginosa for their primary outcome of time until next pulmonary exacerbation. For participants specifically infected with only Pseudomonas aeruginosa, the hazard ratio of a subsequent exacerbation was 0.82, favouring the control group (95% confidence interval 0.44 to 1.51) (P = 0.52). No further data for any of this review's outcomes specific to participants infected with Pseudomonas aeruginosa were available. The risk of bias for the included study was deemed to be low. The quality of the evidence was moderate for the only outcome providing data solely for individuals with infection due to Pseudomonas aeruginosa. For other outcomes, we were unable to judge the quality of the evidence as no data were available for the relevant subset of participants.

AUTHORS' CONCLUSIONS

The current evidence, limited to one study, shows that there is insufficient evidence to determine effect of choosing antibiotics based on combination antimicrobial susceptibility testing compared to choosing antibiotics based on conventional antimicrobial susceptibility testing in the treatment of acute pulmonary exacerbations in people with cystic fibrosis with chronic Pseudomonas aeruginosa infection. A large international and multicentre study is needed to further investigate this issue. The only study included in the review was published in 2005, and we have not identified any further relevant studies up to March 2017. We therefore do not plan to update this review until new studies are published.

Emerging therapies against infections with Pseudomonas aeruginosa

Infections with Pseudomonas aeruginosa have been marked with the highest priority for surveillance and epidemiological research on the basis of parameters such as incidence, case fatality rates, chronicity of illness, available options for prevention and treatment, health-care utilization, and societal impact. P. aeruginosa is one of the six ESKAPE pathogens that are the major cause of nosocomial infections and are a global threat because of their capacity to become increasingly resistant to all available antibiotics. This review reports on current pre-clinical and clinical advances of anti-pseudomonal therapies in the fields of drug development, antimicrobial chemotherapy, vaccines, phage therapy, non-bactericidal pathoblockers, outer membrane sensitizers, and host defense reinforcement.

Aztreonam Lysine Inhalation Solution in Cystic Fibrosis

Patients with cystic fibrosis (CF) develop pulmonary disease secondary to airway infection and dysregulated inflammation. Therapeutic innovations such as nebulized antimicrobial therapy targeting specific pathogens have resulted in improvements in quality of life and life expectancy. Aztreonam lysine for inhalation (AZLI) solution was initially approved to improve respiratory symptoms in CF patients with Pseudomonas aeruginosa (PA) in 2010 by the Food and Drug Administration. Since then, research broadening labeling and clinical application has been developed. In this review, we analyze published and ongoing research regarding AZLI therapy in CF. A search of the Cochrane Database of Systematic Reviews and the PubMed and ClinicalTrials.gov databases was conducted to identify publications about AZLI. Three pre-approval studies were identified and assessed. Two are Phase 3, placebo-controlled trials, assessing a variety of safety and efficacy endpoints, leading to FDA approval. The third is an open-label extension of the two previous trials. An additional seven post-approval, completed trials were identified and are included in this review. They represent a variety of study designs including safety and efficacy in patients with mild lung disease and young patients, an active comparator trial vs inhaled tobramycin, an eradication study, a study among patients with Burkholderia cepacia, and a study assessing continuous alternating antibiotic therapy. Finally, five ongoing clinical trials are discussed. Overall, studies demonstrated that inhaled aztreonam is a safe and effective antimicrobial treatment for the eradication of newly acquired P. aeruginosa and long-term suppressive therapy of chronic endobronchial infection among people with cystic fibrosis.

The effects of cycled inhaled aztreonam on the cystic fibrosis (CF) lung microbiome

BACKGROUND

To improve clinical outcomes, cystic fibrosis (CF) patients with chronic Pseudomonas aeruginosa infections are prescribed inhaled anti-pseudomonal antibiotics. Although, a diverse microbial community exists within CF airways, little is known about how the CF microbiota influences patient outcomes. We hypothesized that organisms within the CF microbiota are affected by inhaled-antibiotics and baseline microbiome may be used to predict therapeutic response.

METHODS

Adults with chronic P. aeruginosa infection from four clinics were observed during a single 28-day on/off inhaled-aztreonam cycle. Patients performed serial sputum collection, CF-respiratory infection symptom scores (CRISS), and spirometry. Patients achieving a decrease of ≥2 CRISS by day 28 were categorized as subjective responders (SR). The airway microbiome was defined by Illumina MiSeq analysis of the 16S rRNA gene.

RESULTS

Thirty-seven patients (median 37.4 years and FEV₁ 44% predicted) were enrolled. No significant cohort-wide changes in the microbiome were observed between on/off AZLI cycles in either alpha- or beta-diversity metrics. However, at an individual level shifts were apparent. Twenty-one patients (57%) were SR and fourteen patients did not subjectively respond. While alpha-diversity metrics did not associate with response, patients who did not subjectively respond had a higher abundance of Staphylococcus and Streptococcus, and lower abundance of Haemophilus.

CONCLUSIONS

The CF microbiome is relatively resilient to AZLI perturbations. However, associated changes were observed at the individual patient level. The relative abundance of key "off-target" organisms associated with subjective improvements suggesting that the microbiome may be used as a tool to predict patient response - potentially improving outcomes.

Inhaled antibiotics for pulmonary exacerbations in cystic fibrosis

BACKGROUND

Cystic fibrosis is a genetic disorder in which abnormal mucus in the lungs is associated with susceptibility to persistent infection. Pulmonary exacerbations are when symptoms of infection become more severe. Antibiotics are an essential part of treatment for exacerbations and inhaled antibiotics may be used alone or in conjunction with oral antibiotics for milder exacerbations or with intravenous antibiotics for more severe infections. Inhaled antibiotics do not cause the same adverse effects as intravenous antibiotics and may prove an alternative in people with poor access to their veins. This is an update of a previously published review.

OBJECTIVES

To determine if treatment of pulmonary exacerbations with inhaled antibiotics in people with cystic fibrosis improves their quality of life, reduces time off school or work and improves their long-term survival.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Group's Cystic Fibrosis Trials Register. Date of the last search: 03 October 2018.We searched ClinicalTrials.gov, the Australia and New Zealand Clinical Trials Registry and WHO ICTRP for relevant trials. Date of last search: 09 October 2018.

SELECTION CRITERIA

Randomised controlled trials in people with cystic fibrosis with a pulmonary exacerbation in whom treatment with inhaled antibiotics was compared to placebo, standard treatment or another inhaled antibiotic for between one and four weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible trials, assessed the risk of bias in each trial and extracted data. They assessed the quality of the evidence using the GRADE criteria. Authors of the included trials were contacted for more information.

MAIN RESULTS

Four trials with 167 participants are included in the review. Two trials (77 participants) compared inhaled antibiotics alone to intravenous antibiotics alone and two trials (90 participants) compared a combination of inhaled and intravenous antibiotics to intravenous antibiotics alone. Trials were heterogenous in design and two were only available in abstract form. Risk of bias was difficult to assess in most trials, but for all trials we judged there to be a high risk from lack of blinding and an unclear risk with regards to randomisation. Results were not fully reported and only limited data were available for analysis.Inhaled antibiotics alone versus intravenous antibiotics aloneOnly one trial (n = 18) reported a perceived improvement in lifestyle (quality of life) in both groups (very low-quality of evidence). Neither trial reported on time off work or school. Both trials measured lung function, but there was no difference reported between treatment groups (very low-quality evidence). With regards to our secondary outcomes, one trial (n = 18) reported no difference in the need for additional antibiotics and the second trial (n = 59) reported on the time to next exacerbation. In neither case was a difference between treatments identified (both very low-quality evidence). The single trial (n = 18) measuring adverse events and sputum microbiology did not observe any in either treatment group for either outcome (very low-quality evidence).Inhaled antibiotics plus intravenous antibiotics versus intravenous antibiotics aloneNeither trial reported on quality of life or time off work or school. Both trials measured lung function, but found no difference between groups in forced expiratory volume in one second (one trial, n = 28, very low-quality evidence) or vital capacity (one trial, n = 62). Neither trial reported on the need for additional antibiotics or the time to the next exacerbation; however, one trial (n = 28) reported on hospital admissions and found no difference between groups. Both trials reported no difference between groups in adverse events (very low-quality evidence) and one trial (n = 62) reported no difference in the emergence of antibiotic-resistant organisms (very low-quality evidence).

AUTHORS' CONCLUSIONS

There is little useful high-level evidence to judge the effectiveness of inhaled antibiotics for the treatment of pulmonary exacerbations in people with cystic fibrosis. The included trials were not sufficiently powered to achieve their goals. Hence, we are unable to demonstrate whether one treatment was superior to the other or not. Further research is needed to establish whether inhaled tobramycin may be used as an alternative to intravenous tobramycin for some pulmonary exacerbations.

Risk of Development of Resistance in Patients with Non-Cystic Fibrosis Bronchiectasis Treated with Inhaled Antibiotics

Purpose of Review

Bronchiectasis is a debilitating chronic lung disease characterised by recurrent bacterial infection and colonisation with significant associated morbidity and mortality. To date, there are few licenced treatments, and the mainstay of clinical management is prompt antibiotic therapy for exacerbations and regular airway clearance. Inhaled antibiotics are a potential long-term treatment for those with recurrent exacerbations, and represent an obvious advantage over other routes of administration as they achieve high concentrations at the site of infection whilst minimising systemic side effects. The main caveat to such treatment is the development of antimicrobial resistance due to altered selection pressures.

Recent Findings

Numerous studies of various inhaled antimicrobials have demonstrated favourable safety and efficacy profiles for bronchiectasis patients with chronic infection, which are supportive of their use in clinical practice.

Summary

There is no convincing evidence of treatment-emergent pathogens or pathogens developing resistance to the inhaled antibiotic therapy.

ECFS best practice guidelines: the 2018 revision

Developments in managing CF continue to drive dramatic improvements in survival. As newborn screening rolls-out across Europe, CF centres are increasingly caring for cohorts of patients who have minimal lung disease on diagnosis. With the introduction of mutation-specific therapies and the prospect of truly personalised medicine, patients have the potential to enjoy good quality of life in adulthood with ever-increasing life expectancy. The landmark Standards of Care published in 2005 set out what high quality CF care is and how it can be delivered throughout Europe. This underwent a fundamental re-write in 2014, resulting in three documents; center framework, quality management and best practice guidelines. This document is a revision of the latter, updating standards for best practice in key aspects of CF care, in the context of a fast-moving and dynamic field. In continuing to give a broad overview of the standards expected for newborn screening, diagnosis, preventative treatment of lung disease, nutrition, complications, transplant/end of life care and psychological support, this consensus on best practice is expected to prove useful to clinical teams both in countries where CF care is developing and those with established CF centres. The document is an ECFS product and endorsed by the CF Network in ERN LUNG and CF Europe.

Antimicrobial molecules in the lung: formulation challenges and future directions for innovation

Inhaled antimicrobials have been extremely beneficial in treating respiratory infections, particularly chronic infections in a lung with cystic fibrosis. The pulmonary delivery of antibiotics has been demonstrated to improve treatment efficacy, reduce systemic side effects and, critically, reduce drug exposure to commensal bacteria compared with systemic administration, reducing selective pressure for antimicrobial resistance. This review will explore the specific challenges of pulmonary delivery of a number of differing antimicrobial molecules, and the formulation and technological approaches that have been used to overcome these difficulties. It will also explore the future challenges being faced in the development of inhaled products and respiratory infection treatment, and identify future directions of innovation, with a particular focus on respiratory infections caused by multiple drug-resistant pathogens.

In vitro evaluation of aerosol delivery of aztreonam lysine (AZLI): an adult mechanical ventilation model

BACKGROUND

The delivery profile of Aztreonam lysine (AZLI) during mechanical ventilation (MV) is unknown. We evaluated the amount of AZLI drug delivered using an in vitro model of adult MV.

METHODS

An adult lung model designed to mimic current clinical practice was used. Both nebulizers were placed before a Y-piece and 4 settings were tested: A) Aeroneb solo® [AS] with a t-piece; B) AS with the spacer; C) M-Neb® [MN] with a t-piece and D) MN with the spacer. Performance was evaluated in terms of: 1) Mass median aerodynamic diameter (MMAD); 2) Geometric standard deviation (GSD), 3) Fine particle dose (FPD), 4) Fine particle fraction (FPF), 5) Inhalable mass (IM), and 6) Recovery rate (RR).

RESULTS

Both devices showed an adequate delivery of AZLI during MV, with MMAD between 2.4-2.5 µm and 87% of FPF. The FPD (38.8 and 31.7), IM (44.8 and 36.1) and RR (30 and 24) were similar for AS and MN respectively. Nebulizer aerosol delivery increased (50 and 70% respectively) for both nebulizers when using the spacer.

CONCLUSION

Both AS and MN showed a good aerosol delivery profile for AZLI during in vitro mechanical ventilation. Better aerosol delivery performance was obtained using the spacer.

Standard versus biofilm antimicrobial susceptibility testing to guide antibiotic therapy in cystic fibrosis

BACKGROUND

The antibiotics used to treat pulmonary infections in people with cystic fibrosis are typically chosen based on the results of antimicrobial susceptibility testing performed on bacteria traditionally grown in a planktonic mode (grown in a liquid). However, there is considerable evidence to suggest that Pseudomonas aeruginosa actually grows in a biofilm (or slime layer) in the airways of people with cystic fibrosis with chronic pulmonary infections. Therefore, choosing antibiotics based on biofilm rather than conventional antimicrobial susceptibility testing could potentially improve response to treatment of Pseudomonas aeruginosa in people with cystic fibrosis. This is an update of a previously published Cochrane Review.

OBJECTIVES

To compare biofilm antimicrobial susceptibility testing-driven therapy to conventional antimicrobial susceptibility testing-driven therapy in the treatment of Pseudomonas aeruginosa infection in people with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Most recent search: 19 June 2017.We also searched two ongoing trials registries and the reference lists of relevant articles and reviews. Most recent searches: 24 August 2017 and 05 September 2017.

SELECTION CRITERIA

Randomized controlled trials of antibiotic therapy based on biofilm antimicrobial susceptibility testing compared to antibiotic therapy based on conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infection in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Both authors independently selected trials, assessed their risk of bias and extracted data from eligible trials. Additionally, the review authors contacted the trial investigators to obtain further information. The quality of the evidence was assessed using the GRADE criteria.

MAIN RESULTS

The searches identified two multicentre, randomized, double-blind controlled clinical trials eligible for inclusion in the review with a total of 78 participants (adults and children); one trial was done in people who were clinically stable, the other in people experiencing pulmonary exacerbations. These trials prospectively assessed whether the use of biofilm antimicrobial susceptibility testing improved microbiological and clinical outcomes in participants with cystic fibrosis who were infected with Pseudomonas aeruginosa. The primary outcome was the change in sputum Pseudomonas aeruginosa density from the beginning to the end of antibiotic therapy.Although the intervention was shown to be safe, the data from these two trials did not provide evidence that biofilm susceptibility testing was superior to conventional susceptibility testing either in terms of microbiological or lung function outcomes. One of the trials also measured risk and time to subsequent exacerbation as well as quality of life measures and did not demonstrate any difference between groups in these outcomes. Both trials had an overall low risk of bias and the quality of the evidence using GRADE criteria was deemed to be moderate to high for the outcomes selected.

AUTHORS' CONCLUSIONS

The current evidence is insufficient to recommend choosing antibiotics based on biofilm antimicrobial susceptibility testing rather than conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infections in people with cystic fibrosis. Biofilm antimicrobial susceptibility testing may be more appropriate in the development of newer, more effective formulations of drugs which can then be tested in clinical trials.

Brazilian guidelines for the diagnosis and treatment of cystic fibrosis

Cystic fibrosis (CF) is an autosomal recessive genetic disorder characterized by dysfunction of the CFTR gene. It is a multisystem disease that most often affects White individuals. In recent decades, various advances in the diagnosis and treatment of CF have drastically changed the scenario, resulting in a significant increase in survival and quality of life. In Brazil, the current neonatal screening program for CF has broad coverage, and most of the Brazilian states have referral centers for the follow-up of individuals with the disease. Previously, CF was limited to the pediatric age group. However, an increase in the number of adult CF patients has been observed, because of the greater number of individuals being diagnosed with atypical forms (with milder phenotypic expression) and because of the increase in life expectancy provided by the new treatments. However, there is still great heterogeneity among the different regions of Brazil in terms of the access of CF patients to diagnostic and therapeutic methods. The objective of these guidelines was to aggregate the main scientific evidence to guide the management of these patients. A group of 18 CF specialists devised 82 relevant clinical questions, divided into five categories: characteristics of a referral center; diagnosis; treatment of respiratory disease; gastrointestinal and nutritional treatment; and other aspects. Various professionals working in the area of CF in Brazil were invited to answer the questions devised by the coordinators. We used the PubMed database to search the available literature based on keywords, in order to find the best answers to these questions.

Strategies for the etiological therapy of cystic fibrosis

Etiological therapies aim at repairing the underlying cause of cystic fibrosis (CF), which is the functional defect of the cystic fibrosis transmembrane conductance regulator (CFTR) protein owing to mutations in the CFTR gene. Among these, the F508del CFTR mutation accounts for more than two thirds of CF cases worldwide. Two somehow antinomic schools of thought conceive CFTR repair in a different manner. According to one vision, drugs should directly target the mutated CFTR protein to increase its plasma membrane expression (correctors) or improve its ion transport function (potentiators). An alternative strategy consists in modulating the cellular environment and proteostasis networks in which the mutated CFTR protein is synthesized, traffics to its final destination, the plasma membrane, and is turned over. We will analyze distinctive advantages and drawbacks of these strategies in terms of their scientific and clinical dimensions, and we will propose a global strategy for CF research and development based on a reconciliatory approach. Moreover, we will discuss the utility of preclinical biomarkers that may guide the personalized, patient-specific implementation of CF therapies.

Relevance of multidrug-resistant Pseudomonas aeruginosa infections in cystic fibrosis

Multidrug-resistant (MDR) Pseudomonas aeruginosa is an important issue for physicians who take care of patients with cystic fibrosis (CF). Here, we review the latest research on how P. aeruginosa infection causes lung function to decline and how several factors contribute to the emergence of antibiotic resistance in P. aeruginosa strains and influence the course of the infection course. However, many aspects of the practical management of patients with CF infected with MDR P. aeruginosa are still to be established. Less is known about the exact role of susceptibility testing in clinical strategies for dealing with resistant infections, and there is an urgent need to find a tool to assist in choosing the best therapeutic strategy for MDR P. aeruginosa infection. One current perception is that the selection of antibiotic therapy according to antibiogram results is an important component of the decision-making process, but other patient factors, such as previous infection history and antibiotic courses, also need to be evaluated. On the basis of the known issues and the best current data on respiratory infections caused by MDR P. aeruginosa, this review provides practical suggestions to optimize the diagnostic and therapeutic management of patients with CF who are infected with these pathogens.

Combination antimicrobial susceptibility testing for acute exacerbations in chronic infection of Pseudomonas aeruginosa in cystic fibrosis

BACKGROUND

Antibiotic therapy for acute pulmonary exacerbations in people with cystic fibrosis is usually chosen based on the results of antimicrobial susceptibility testing of individual drugs. Combination antimicrobial susceptibility testing assesses the efficacy of drug combinations including two or three antibiotics in vitro and can often demonstrate antimicrobial efficacy against bacterial isolates even when individual antibiotics have little or no effect. Therefore, choosing antibiotics based on combination antimicrobial susceptibility testing could potentially improve response to treatment in people with cystic fibrosis with acute exacerbations. This is an updated version of a previously published review.

OBJECTIVES

To compare antibiotic therapy based on conventional antimicrobial susceptibility testing to antibiotic therapy based on combination antimicrobial susceptibility testing in the treatment of acute pulmonary exacerbations in people with cystic fibrosis and chronic infection with Pseudomonas aeruginosa.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Cystic Fibrosis Trials Register which comprises of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of latest search: 19 December 2016.We also searched ongoing trials registries. Date of latest search: 08 March 2017.

SELECTION CRITERIA

Randomised and quasi-randomised controlled studies of antibiotic therapy based on conventional antimicrobial susceptibility testing compared to antibiotic therapy based on combination antimicrobial susceptibility testing in the treatment of acute pulmonary exacerbations in cystic fibrosis due to chronic infection with Pseudomonas aeruginosa.

DATA COLLECTION AND ANALYSIS

Both authors independently selected studies, assessed their quality and extracted data from eligible studies. Additionally, the authors contacted the study investigators to obtain further information.

MAIN RESULTS

The search identified one multicentre study eligible for inclusion in the review. This study prospectively assessed whether the use of multiple combination bactericidal antibiotic testing improved clinical outcomes in participants with acute pulmonary exacerbations of cystic fibrosis who were infected with multiresistant bacteria. A total of 132 participants were randomised in the study. The study investigators provided data specific to the 82 participants who were only infected with Pseudomonas aeruginosa for their primary outcome of time until next pulmonary exacerbation. For participants specifically infected with only Pseudomonas aeruginosa, the hazard ratio of a subsequent exacerbation was 0.82, favouring the control group (95% confidence interval 0.44 to 1.51) (P = 0.52). No further data for any of this review's outcomes specific to participants infected with Pseudomonas aeruginosa were available. The risk of bias for the included study was deemed to be low. The quality of the evidence was moderate for the only outcome providing data solely for individuals with infection due to Pseudomonas aeruginosa. For other outcomes, we were unable to judge the quality of the evidence as no data were available for the relevant subset of participants.

AUTHORS' CONCLUSIONS

The current evidence, limited to one study, shows that there is insufficient evidence to determine effect of choosing antibiotics based on combination antimicrobial susceptibility testing compared to choosing antibiotics based on conventional antimicrobial susceptibility testing in the treatment of acute pulmonary exacerbations in people with cystic fibrosis with chronic Pseudomonas aeruginosa infection. A large international and multicentre study is needed to further investigate this issue.The only study included in the review was published in 2005, and we have not identified any further relevant studies up to March 2017. We therefore do not plan to update this review until new studies are published.

The treatment of the pulmonary and extrapulmonary manifestations of cystic fibrosis

Cystic fibrosis (CF) is a complex multisystem disease with considerable between patient variability in its manifestations and severity. In the past several decades, the range of treatments and the evidence to support their use for the pulmonary and extrapulmonary manifestations of CF have increased dramatically, contributing to the improved median survival of patients. As therapy for CF has evolved, new challenges including treatment adherence, medication intolerance and allergy, medical complications and coping with the burden of disease in the context of having a family and managing employment have arisen. While the majority of current therapy focuses primarily on improving symptoms, new therapies (CFTR modulators) target the underlying genetic defect.

Inhaled Antibiotic Therapy in Chronic Respiratory Diseases

The management of patients with chronic respiratory diseases affected by difficult to treat infections has become a challenge in clinical practice. Conditions such as cystic fibrosis (CF) and non-CF bronchiectasis require extensive treatment strategies to deal with multidrug resistant pathogens that include Pseudomonas aeruginosa, Methicillin-resistant Staphylococcus aureus, Burkholderia species and non-tuberculous Mycobacteria (NTM). These challenges prompted scientists to deliver antimicrobial agents through the pulmonary system by using inhaled, aerosolized or nebulized antibiotics. Subsequent research advances focused on the development of antibiotic agents able to achieve high tissue concentrations capable of reducing the bacterial load of difficult-to-treat organisms in hosts with chronic respiratory conditions. In this review, we focus on the evidence regarding the use of antibiotic therapies administered through the respiratory system via inhalation, nebulization or aerosolization, specifically in patients with chronic respiratory diseases that include CF, non-CF bronchiectasis and NTM. However, further research is required to address the potential benefits, mechanisms of action and applications of inhaled antibiotics for the management of difficult-to-treat infections in patients with chronic respiratory diseases.

The effects of inhaled aztreonam on the cystic fibrosis lung microbiome

BACKGROUND

Aztreonam lysine for inhalation (AZLI) is an inhaled antibiotic used to treat chronic Pseudomonas aeruginosa infection in CF. AZLI improves lung function and quality of life, and reduces exacerbations-improvements attributed to its antipseudomonal activity. Given the extremely high aztreonam concentrations achieved in the lower airways by nebulization, we speculate this may extend its spectrum of activity to other organisms. As such, we sought to determine if AZLI affects the CF lung microbiome and whether community constituents can be used to predict treatment responsiveness.

METHODS

Patients were included if they had chronic P. aeruginosa infection and repeated sputum samples collected before and after AZLI. Sputum DNA was extracted, and the V3-hypervariable region of the 16S ribosomal RNA (rRNA) gene amplified and sequenced.

RESULTS

Twenty-four patients naïve to AZLI contributed 162 samples. The cohort had a median age of 37.1 years, and a  median FEV₁ of 44% predicted. Fourteen patients were a priori defined as responders for achieving ≥3% FEV₁ improvement following initiation. No significant changes in alpha diversity were noted following AZLI. Furthermore, beta diversity demonstrated clustering with respect to patients, but had no association with AZLI use. However, we did observe a decline in the relative abundance of several individual operational taxonomic units (OTUs) following AZLI initiation suggesting that specific sub-populations of organisms may be impacted. Patients with higher abundance of Staphylococcus and anaerobic organisms including Prevotella and Fusobacterium were less likely to respond to therapy.

CONCLUSIONS

Results from our study suggest potential alternate/additional mechanisms by which AZLI functions. Moreover, our study suggests that the CF microbiota may be used as a biomarker to predict patient responsiveness to therapy suggesting the microbiome may be harnessed for the personalization of therapies.

Antibiotic strategies for eradicating Pseudomonas aeruginosa in people with cystic fibrosis

BACKGROUND

Respiratory tract infection with Pseudomonas aeruginosa occurs in most people with cystic fibrosis. Once chronic infection is established, Pseudomonas aeruginosa is virtually impossible to eradicate and is associated with increased mortality and morbidity. Early infection may be easier to eradicate.This is an update of a Cochrane review first published in 2003, and previously updated in 2006, 2009 and 2014.

OBJECTIVES

To determine whether antibiotic treatment of early Pseudomonas aeruginosa infection in children and adults with cystic fibrosis eradicates the organism, delays the onset of chronic infection, and results in clinical improvement. To evaluate whether there is evidence that a particular antibiotic strategy is superior to or more cost-effective than other strategies and to compare the adverse effects of different antibiotic strategies (including respiratory infection with other micro-organisms).

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings.Most recent search: 10 October 2016.

SELECTION CRITERIA

We included randomised controlled trials of people with cystic fibrosis, in whom Pseudomonas aeruginosa had recently been isolated from respiratory secretions. We compared combinations of inhaled, oral or intravenous antibiotics with placebo, usual treatment or other combinations of inhaled, oral or intravenous antibiotics. We excluded non-randomised trials, cross-over trials, and those utilising historical controls.

DATA COLLECTION AND ANALYSIS

Both authors independently selected trials, assessed risk of bias and extracted data.

MAIN RESULTS

The search identified 60 trials; seven trials (744 participants) with a duration between 28 days and 27 months were eligible for inclusion. Three of the trials are over 10 years old and their results may be less applicable today given the changes in standard treatment. Some of the trials had low numbers of participants and most had relatively short follow-up periods; however, there was generally a low risk of bias from missing data. In most trials it was difficult to blind participants and clinicians to treatment given the interventions and comparators used. Two trials were supported by the manufacturers of the antibiotic used.Evidence from two trials (38 participants) at the two-month time-point showed treatment of early Pseudomonas aeruginosa infection with inhaled tobramycin results in microbiological eradication of the organism from respiratory secretions more often than placebo, odds ratio 0.15 (95% confidence interval (CI) 0.03 to 0.65) and data from one of these trials, with longer follow up, suggested that this effect may persist for up to 12 months.One randomised controlled trial (26 participants) compared oral ciprofloxacin and nebulised colistin versus usual treatment. Results after two years suggested treatment of early infection results in microbiological eradication of Pseudomonas aeruginosa more often than no anti-pseudomonal treatment, odds ratio 0.12 (95% CI 0.02 to 0.79).One trial comparing 28 days to 56 days treatment with nebulised tobramycin solution for inhalation in 88 participants showed that both treatments were effective and well-tolerated, with no notable additional improvement with longer over shorter duration of therapy. However, this trial was not powered to detect non-inferiority or equivalence .A trial of oral ciprofloxacin with inhaled colistin versus nebulised tobramycin solution for inhalation alone (223 participants) failed to show a difference between the two strategies, although it was underpowered to show this. A further trial of inhaled colistin with oral ciprofloxacin versus nebulised tobramycin solution for inhalation with oral ciprofloxacin also showed no superiority of the former, with increased isolation of Stenotrophomonas maltophilia in both groups.A recent, large trial in 306 children aged between one and 12 years compared cycled nebulised tobramycin solution for inhalation to culture-based therapy and also ciprofloxacin to placebo. The primary analysis showed no difference in time to pulmonary exacerbation or proportion of Pseudomonas aeruginosa positive cultures. An analysis performed in this review (not adjusted for age) showed fewer participants in the cycled therapy group with one or more isolates of Pseudomonas aeruginosa, odds ratio 0.51 (95% CI 0.31 to 0.28). Using GRADE, the quality of evidence for outcomes was downgraded to moderate to very low. Downgrading decisions for Pseudomonas aeruginosa eradication and lung function were based on applicability (participants mostly children) and limitations in study design, with imprecision an additional limitation for lung function, growth parameters and adverse effects.

AUTHORS' CONCLUSIONS

We found that nebulised antibiotics, alone or in combination with oral antibiotics, were better than no treatment for early infection with Pseudomonas aeruginosa. Eradication may be sustained for up to two years. There is insufficient evidence to determine whether antibiotic strategies for the eradication of early Pseudomonas aeruginosa decrease mortality or morbidity, improve quality of life, or are associated with adverse effects compared to placebo or standard treatment. Four trials comparing two active treatments have failed to show differences in rates of eradication of Pseudomonas aeruginosa. There have been no published randomised controlled trials that investigate the efficacy of intravenous antibiotics to eradicate Pseudomonas aeruginosa in cystic fibrosis. Overall, there is still insufficient evidence from this review to state which antibiotic strategy should be used for the eradication of early Pseudomonas aeruginosa infection in cystic fibrosis.

Long-term safety of tobramycin inhalation powder in patients with cystic fibrosis: phase IV (ETOILES) study

OBJECTIVE

Long-term treatment with inhaled antibiotics is recommended for chronic Pseudomonas aeruginosa (Pa) infection in cystic fibrosis (CF) patients. The ETOILES study (Clinicaltrials.gov identifier: NCT01519661) evaluated the safety of tobramycin inhalation powder (TIP) for 1 year.

RESEARCH DESIGN AND METHODS

This single-arm, open-label, multicenter, phase IV trial, enrolled CF patients aged ≥6 years, with baseline FEV₁ ≥25%-≤75% predicted and Pa infection, and assessed the safety of TIP over six cycles in terms of the incidence of treatment-emergent adverse events (AEs) and serious AEs (SAEs). Secondary endpoints included presence of airway reactivity, relative change in FEV₁% predicted, and change in sputum Pa density (log₁₀ colony forming units/g sputum).

RESULTS

A total of 157 patients were enrolled, and 96 patients (61.1%) completed the study. The most commonly reported AE was infective pulmonary exacerbation of CF (55.4%). Cough was reported as an AE in 23.6% of patients; a majority were mild or moderate and two were severe (1.3%). SAEs were reported by 31.2% of patients. No deaths were reported during the study. There were no clinically meaningful changes reported in airway reactivity. Most frequently reported post-inhalation event was cough at all time points; however, it was of short duration (<4 minutes) and decreased over the course of the study, possibly due to patients becoming more experienced with the administration of TIP. The post-inhalation events resolved without intervention in most cases. FEV₁% predicted remained stable from Cycles 1 to 4 and tended to decrease thereafter, although it was not statistically significant (change from baseline to study end mean [SD] = -1.9% [14.55]; P = 0.199).

CONCLUSIONS

This was one of the largest studies with long-term TIP exposure. The majority of patients enrolled were adults with more advanced CF lung disease than those in previous TIP studies. No new emerging safety signals were seen and efficacy was sustained during the year.

Biomarkers for cystic fibrosis drug development

PURPOSE

To provide a review of the status of biomarkers in cystic fibrosis drug development, including regulatory definitions and considerations, a summary of biomarkers in current use with supportive data, current gaps, and future needs.

METHODS

Biomarkers are considered across several areas of CF drug development, including cystic fibrosis transmembrane conductance regulator modulation, infection, and inflammation.

RESULTS

Sweat chloride, nasal potential difference, and intestinal current measurements have been standardized and examined in the context of multicenter trials to quantify CFTR function. Detection and quantification of pathogenic bacteria in CF respiratory cultures (e.g.: Pseudomonas aeruginosa) are commonly used in early phase antimicrobial clinical trials, and to monitor safety of therapeutic interventions. Sputum (e.g.: neutrophil elastase, myeloperoxidase, calprotectin) and blood biomarkers (e.g.: C reactive protein, calprotectin, serum amyloid A) have had variable success in detecting response to inflammatory treatments.

CONCLUSIONS

Biomarkers are used throughout the drug development process in CF, and many have been used in early phase clinical trials to provide proof of concept, detect drug bioactivity, and inform dosing for later-phase studies. Advances in the precision of current biomarkers, and the identification of new biomarkers with 'omics-based technologies, are needed to accelerate CF drug development.

The Approach to Pseudomonas aeruginosa in Cystic Fibrosis

There is a high prevalence of Pseudomonas aeruginosa in patients with cystic fibrosis and clear epidemiologic links between chronic infection and morbidity and mortality exist. Prevention and early identification of infection are critical, and stand to improve with the advent of new vaccines and laboratory methods. Once the organism is identified, a variety of treatment options are available. Aggressive use of antipseudomonal antibiotics is the standard of care for acute pulmonary exacerbations in cystic fibrosis, and providers must take into account specific patient characteristics when making treatment decisions related to antibiotic selection, route and duration of administration, and site of care.

Current and future treatment options for cystic fibrosis lung disease: latest evidence and clinical implications

Treatment for cystic fibrosis (CF) has conventionally targeted downstream consequences of the defect such as mucus plugging and infection. More recently, significant advances have been made in treating the root cause of the disease, namely a defective CF transmembrane conductance regulator (CFTR) gene. This review summarizes current pulmonary treatment options and highlights advances in research and development of new therapies.

Sequential Treatment of Biofilms with Aztreonam and Tobramycin Is a Novel Strategy for Combating Pseudomonas aeruginosa Chronic Respiratory Infections

Traditional therapeutic strategies to control chronic colonization in cystic fibrosis (CF) patients are based on the use of a single nebulized antibiotic. In this study, we evaluated the therapeutic efficacy and dynamics of antibiotic resistance in Pseudomonas aeruginosa biofilms under sequential therapy with inhaled aztreonam (ATM) and tobramycin (TOB). Laboratory strains PAO1, PAOMS (hypermutable), PAOMA (mucoid), and PAOMSA (mucoid and hypermutable) and two hypermutable CF strains, 146-HSE (Liverpool epidemic strain [LES-1]) and 1089-HSE (ST1089), were used. Biofilms were developed using the flow cell system. Mature biofilms were challenged with peak and 1/10-peak concentrations of ATM (700 mg/liter and 70 mg/liter), TOB (1,000 mg/liter and 100 mg/liter), and their alternations (ATM/TOB/ATM and TOB/ATM/TOB) for 2 (t = 2), 4 (t = 4), and 6 days (t = 6). The numbers of viable cells (CFU) and resistant mutants were determined. Biofilm structural dynamics were monitored by confocal laser scanning microscopy and processed with COMSTAT and IMARIS software programs. TOB monotherapy produced an intense decrease in CFU that was not always correlated with a reduction in biomass and/or a bactericidal effect on biofilms, particularly for the CF strains. The ATM monotherapy bactericidal effect was lower, but effects on biofilm biomass and/or structure, including intense filamentation, were documented. The alternation of TOB and ATM led to an enhancement of the antibiofilm activity against laboratory and CF strains compared to that with the individual regimens, potentiating the bactericidal effect and/or the reduction in biomass, particularly at peak concentrations. Resistant mutants were not documented in any of the regimens at the peak concentrations and only anecdotally at the 1/10-peak concentrations. These results support the clinical evaluation of sequential regimens with inhaled antibiotics in CF, as opposed to the current maintenance treatments with just one antibiotic in monotherapy.

Chest CT abnormalities and quality of life: relationship in adult cystic fibrosis

BACKGROUND

To evaluate the relationship between lung parenchymal abnormalities on chest CT and health-related quality of life in adult cystic fibrosis (CF).

METHODS

The chest CT scans of 101 consecutive CF adults (mean age 27.8±7.9, 64 males) were prospectively scored by two blinded radiologists in consensus using a modified Bhalla score. Health-related quality of life was assessed using the revised Quittner Cystic Fibrosis Questionnaire (CFQ-R). Multiple regressions were performed with each of the CFQ-R domains and all clinical and imaging findings to assess independent correlations.

RESULTS

There were 18 inpatients and 83 outpatients. For the cohort of inpatients, CT abnormalities were significantly (P<0.005 for all) associated with Respiratory Symptoms (Air Trapping), and also with Social Functioning (Consolidation) and Role Functioning (Consolidation). For outpatients, CT abnormalities were significantly (P<0.005 for all) associated with Respiratory Symptoms (Consolidation) and also with Physical Functioning (Consolidation), Vitality (Consolidation, Severity of Bronchiectasis), Eating Problems (airway wall thickening), Treatment Burden (Total CT Score), Body Image (Severity of Bronchiectasis) and Role Functioning (Tree-in-bud nodules). Consolidation was the commonest independent CT predictor for both inpatients (predictor for 2 domains) and outpatients (predictor in 3 domains). Several chest CT abnormalities excluded traditional measures such as FEV1 and BMI from the majority of CFQ-R domains.

CONCLUSIONS

Chest CT abnormalities are significantly associated with quality of life measures in adult CF, independent of clinical or spirometric measurements.

Clinical Practice Guidelines From the Cystic Fibrosis Foundation for Preschoolers With Cystic Fibrosis

Cystic fibrosis (CF) clinical care guidelines exist for the care of infants up to age 2 years and for individuals ≥6 years of age. An important gap exists for preschool children between the ages of 2 and 5 years. This period marks a time of growth and development that is critical to achieve optimal nutritional status and maintain lung health. Given that disease often progresses in a clinically silent manner, objective and sensitive tools that detect and track early disease are important in this age group. Several challenges exist that may impede the delivery of care for these children, including adherence to therapies. A multidisciplinary committee was convened by the CF Foundation to develop comprehensive evidence-based and consensus recommendations for the care of preschool children, ages 2 to 5 years, with CF. This document includes recommendations in the following areas: routine surveillance for pulmonary disease, therapeutics, and nutritional and gastrointestinal care.

Efficacy and toxicity of aerosolised colistin in ventilator-associated pneumonia: a prospective, randomised trial

Background

Cases of ventilator-associated pneumonia (VAP) due to multidrug-resistant (MDR) gram-negative bacilli (GNB) mainly Acinetobacter baumannii, Pseudomonas aeruginosa and enterobacteria are common in hospitalised patients of Tunisian intensive care units (ICUs). Parenteral colistin has been used for the therapy of VAP caused by MDR GNB at Tunisian hospitals over the past few years with a favourable clinical response. However, its use fell out of favour because of the reported drug-related nephrotoxicity and neurotoxicity.

Objectives

To determine whether aerosolised (AS) colistin was beneficial and safe in therapy of gram-negative VAP.

Methods

This was a randomised, single-blind study, in 149 critically ill adults who developed gram-negative VAP. Included patients were divided into two groups whether they received AS colistin (intervention group; n = 73) or intravenous (IV) colistin (control group; n = 76). AS colistin was given as 4 million units (MU) by nebulisation three times per 24 h. IV colistin was given as a loading dose of 9 MU followed by 4.5 MU two times per 24 h. Patients were followed during 28 days. Primary outcome was cure of VAP assessed at day 14 of therapy and defined as resolution of clinical signs of VAP and bacteriological eradication. Secondary outcomes were incidence of acute renal failure (ARF), mechanical ventilation length, ICU length of stay and 28-day mortality. Results were analysed based on intention-to-treat concept.

Results

The patient’s baseline characteristics and distribution of pathogens VAP in both groups were similar. The clinical cure rate was 67.1 % in AS group and 72 % in IV group (p = 0.59). When administered in monotherapy or in combination, the AS regimen was as effective as IV regimen. Patients in AS group had significantly lower incidence of ARF (17.8 vs 39.4 %, p = 0.004), more favourable improvement of P/F ratio (349 vs 316 at day 14, p = 0.012), shortened time to bacterial eradication (TBE) (9.89 vs 11.26 days, p = 0.023) and earlier weaning from ventilator in ICU survivors with a mean gain in ventilator-free days of 5 days. No difference was shown in the length of stay and the 28-day mortality.

Conclusion

Aerosolised colistin seems to be beneficial. It provided a therapeutic effectiveness non-inferior to parenteral colistin in therapy of MDR bacilli VAP with a lower nephrotoxicity, a better improvement of P/F ratio, a shortened bacterial eradication time and earlier weaning from ventilator in ICU survivors.

Trial registration ClinicalTrials.gov Identifier: NCT02683603