Dornase alfa for cystic fibrosis

Physiology and pathophysiology of mucus and mucolytic use in critically ill patients

Airway mucus is a highly specialised secretory fluid which functions as a physical and immunological barrier to pathogens whilst lubricating the airways and humifying atmospheric air. Dysfunction is common during critical illness and is characterised by changes in production rate, chemical composition, physical properties, and inflammatory phenotype. Mucociliary clearance, which is determined in part by mucus characteristics and in part by ciliary function, is also dysfunctional in critical illness via disease related and iatrogenic mechanisms. The consequences of mucus dysfunction are potentially devastating, contributing to prolonged ventilator dependency, increased risk of secondary pneumonia, and worsened lung injury. Mucolytic therapies are designed to decrease viscosity, improve expectoration/suctioning, and thereby promote mucus removal. Mucolytics, including hypertonic saline, dornase alfa/rhDNase, nebulised heparin, carbocisteine/N-Acetyl cysteine, are commonly used in critically ill patients. This review summarises the physiology and pathophysiology of mucus and the existing evidence for the use of mucolytics in critically ill patients and speculates on journey to individualised mucolytic therapy.

"The NET effect": Neutrophil extracellular traps-a potential key component of the dysregulated host immune response in sepsis

Neutrophils release neutrophil extracellular traps (NETs) as part of a healthy host immune response. NETs physically trap and kill pathogens as well as activating and facilitating crosstalk between immune cells and complement. Excessive or inadequately resolved NETs are implicated in the underlying pathophysiology of sepsis and other inflammatory diseases, including amplification of the inflammatory response and inducing thrombotic complications. Here, we review the growing evidence implicating neutrophils and NETs as central players in the dysregulated host immune response. We discuss potential strategies for modifying NETs to improve patient outcomes and the need for careful patient selection.

Targeted DNase treatment of obstructive lung disease: a pilot randomised controlled trial

Background

Sputum extracellular DNA (eDNA) is associated with disease severity in asthma and COPD and therefore emerging as a potential therapeutic target. The aim of this study was to investigate the effect of 10 days of recombinant human DNase (rhDNase) treatment of eDNA-high asthma and COPD on sputum eDNA levels, neutrophil-related inflammation, lung function and symptoms.

Methods

Adults with asthma (n=80) or COPD (n=66) were screened for the presence of high (>20 µg·mL-1) sputum eDNA and those eligible (n=18 asthma, n=17 COPD) were randomised to a two-period crossover controlled trial consisting of daily nebulised rhDNase (2.5 mg/2.5 mL) or placebo (5 mL 0.9% saline) for 10 days, with a 2-week washout period. The primary outcome was sputum eDNA, and secondary outcomes included sputum neutrophil extracellular trap (NET)-related biomarkers, inflammatory cell counts, lung function and respiratory symptoms.

Results

At screening, high eDNA was associated with significantly higher sputum total cell count, sputum colour score and inflammation (HNP1-3, LL-37 and interleukin-1β) in both asthma and COPD compared to low eDNA groups. In asthma, participants with high eDNA were older and had poorer lung function and asthma control compared to low eDNA. Administration of nebulised rhDNase significantly reduced sputum eDNA levels in both asthma (median (Q1-Q3) Pre: 48.4 (22.1-74.1); Post: 17.0 (5.0-31.0) µg·mL-1; p=0.022) and COPD (median (Q1-Q3) Pre: 39.3 (36.7-55.6); Post: 25.4 (11.3-38.6) µg·mL-1; p=0.044) compared to placebo. Symptoms, lung function and NET biomarkers remained unchanged. In asthma, there was a reduction in banded blood neutrophils (3.2 (0-7.7) to 0.0 (0.0-1.5); p=0.044).

Conclusion

Targeted rhDNase treatment for 10 days effectively reduced sputum eDNA in eDNA-high asthma and COPD.

Mucoactive drugs and multiple applications in pulmonary disease therapy

Mucus is a complex polymeric hydrogel that serves as a critical defense in several organs. In the lungs, it provides a formidable barrier against inhaled particles such as microorganisms. In addition, mucus is essential for normal lung physiology, as it promotes immune tolerance and facilitates a normal commensal pulmonary microbiome. Hypersecretion of airway mucus is a characteristic of numerous respiratory diseases, such as Chronic Obstructive Pulmonary Disease (COPD) and Cystic Fibrosis (CF), and creates pulmonary obstruction, limiting the effectiveness of inhaled therapies. Due to those alterations, therapeutic strategies must be optimal to limit airway obstruction and restore pulmonary function. Mucoactive drugs are common therapeutic options and are classified into different groups depending on their modes of action, i.e., expectorants, mucokinetics, mucoregulators and mucolytics. This review focuses on mucoactive drugs and their modes of action. A special focus will be made on two challenging pulmonary pathologies: COPD and CF, and on their clinical studies conducted with mucoactive drugs.

Extracellular DNA enhances biofilm integrity and mechanical properties of mucoid Pseudomonas aeruginosa

Pseudomonas aeruginosa is one of the most common biofilm-forming pathogens responsible for lung infections of individuals with cystic fibrosis (CF). P. aeruginosa becomes tolerant to antimicrobials in the biofilm state and is difficult to treat. Production of extracellular polymeric substances (EPS), such as alginate and extracellular DNA (eDNA), can allow adherence to abiotic and biotic surfaces, antimicrobial evasion, and resilience to environmental pressures. Alginate-producing mucoid variants of P. aeruginosa are frequently isolated from CF airway samples and are associated with worsening patient outcomes. While eDNA is a major structural component of nonmucoid P. aeruginosa biofilms, the potential role of eDNA in mucoid biofilms is unclear. Here, we investigate how eDNA contributes to clinical mucoid biofilm physiology and integrity. We predicted that eDNA plays a structural and mechanical role in mucoid biofilms. To test this, we quantified biofilm eDNA in mucoid biofilms and used microscopy and rheology to visualize eDNA and detect changes in biofilm structure and mechanics upon DNaseI treatment. We showed that biofilm eDNA abundance is diverse across clinical mucoid strains and observed a temporal increase in foci of eDNA within intact mucoid biofilms. Increased cell dispersal and reduced biomass were also observed following DNaseI treatment of mucoid biofilms. Degradation of eDNA also impacted the mechanical integrity of mucoid biofilms by increasing the stiffness and decreasing the cohesion of the biofilm. These findings advance our understanding of clinical mucoid P. aeruginosa biofilms and facilitate the development of new approaches to target biofilms by exploiting the functions of EPS components. IMPORTANCE Understanding the role of eDNA in mucoid Pseudomonas aeruginosa biofilms will lead to therapeutic strategies that combat the biophysical and structural function of EPS for the eradication of bacteria in mucoid biofilms during chronic infections. This knowledge can be used to further identify unknown matrix component interactions within pathogenic biofilm-forming clinical isolates.

Emulated trial investigating effects of multiple treatments: estimating combined effects of mucoactive nebulisers in cystic fibrosis using registry data

INTRODUCTION

People with cystic fibrosis (CF) are often on multiple long-term treatments, including mucoactive nebulisers. In the UK, the most common mucoactive nebuliser is dornase alfa (DNase). A common therapeutic approach for people already on DNase is to add hypertonic saline (HS). The effects of DNase and HS used alone have been studied in randomised trials, but their effects in combination have not. This study investigates whether, for people already prescribed DNase, adding HS has additional benefit for lung function or use of intravenous antibiotics.

METHODS

Using UK CF Registry data from 2007 to 2018, we emulated a target trial. We included people aged 6 years and over who were prescribed DNase without HS for 2 years. We investigated the effects of combinations of DNase and HS over 5 years of follow-up. Inverse-probability-of-treatment weighting was used to control confounding. The period predated triple combination CF transmembrane conductance regulator modulators in routine care.

RESULTS

4498 individuals were included. At baseline, average age and forced expiratory volume in 1 s (FEV1%) predicted were 21.1 years and 69.7 respectively. During first year of follow-up, 3799 individuals were prescribed DNase alone; 426 added HS; 57 switched to HS alone and 216 were prescribed neither. We found no evidence that adding HS improved FEV1% at 1-5 years, or use of intravenous antibiotics at 1-4 years, compared with DNase alone.

CONCLUSION

For individuals with CF prescribed DNase, we found no evidence that adding HS had an effect on FEV1% or prescription of intravenous antibiotics. Our study illustrates the emulated target trial approach using CF Registry data.

Causal inference in survival analysis using longitudinal observational data: Sequential trials and marginal structural models

Longitudinal observational data on patients can be used to investigate causal effects of time-varying treatments on time-to-event outcomes. Several methods have been developed for estimating such effects by controlling for the time-dependent confounding that typically occurs. The most commonly used is marginal structural models (MSM) estimated using inverse probability of treatment weights (IPTW) (MSM-IPTW). An alternative, the sequential trials approach, is increasingly popular, and involves creating a sequence of "trials" from new time origins and comparing treatment initiators and non-initiators. Individuals are censored when they deviate from their treatment assignment at the start of each "trial" (initiator or noninitiator), which is accounted for using inverse probability of censoring weights. The analysis uses data combined across trials. We show that the sequential trials approach can estimate the parameters of a particular MSM. The causal estimand that we focus on is the marginal risk difference between the sustained treatment strategies of "always treat" vs "never treat." We compare how the sequential trials approach and MSM-IPTW estimate this estimand, and discuss their assumptions and how data are used differently. The performance of the two approaches is compared in a simulation study. The sequential trials approach, which tends to involve less extreme weights than MSM-IPTW, results in greater efficiency for estimating the marginal risk difference at most follow-up times, but this can, in certain scenarios, be reversed at later time points and relies on modelling assumptions. We apply the methods to longitudinal observational data from the UK Cystic Fibrosis Registry to estimate the effect of dornase alfa on survival.

Psychological interventions for improving adherence to inhaled therapies in people with cystic fibrosis

BACKGROUND

Adherence to treatment, including inhaled therapies, is low in people with cystic fibrosis (CF). Although psychological interventions for improving adherence to inhaled therapies in people with CF have been developed, no previous published systematic review has evaluated the evidence for efficacy of these interventions.

OBJECTIVES

The primary objective of the review was to assess the efficacy of psychological interventions for improving adherence to inhaled therapies in people with cystic fibrosis (CF). The secondary objective was to establish the most effective components, or behaviour change techniques (BCTs), used in these interventions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, which is compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched databases (PubMed; PsycINFO; EBSCO; Scopus; OpenGrey), trials registries (World Health Organization International Clinical Trials Registry Platform; US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov), and the reference lists of relevant articles and reviews, with no restrictions on language, year or publication status. Date of search: 7 August 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different types of psychological interventions for improving adherence to inhaled therapies in people with CF of any age, or comparing psychological interventions with usual care. We included quasi-RCTs if we could reasonably assume that the baseline characteristics were similar in both groups.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility and completed data extraction, risk of bias assessments, and BCT coding (using the BCT Taxonomy v1) for all included trials. We resolved any discrepancies by discussion, or by consultation with a third review author as necessary. We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 10 trials (1642 participants) in the review (children and adolescents in four trials; adults in five trials; and children and adults in one trial). Nine trials compared a psychological intervention with usual care; we could combine data from some of these in a number of quantitative analyses. One trial compared a psychological intervention with an active comparator (education plus problem-solving (EPS)). We identified five ongoing trials. Psychological interventions were generally multi-component and complex, containing an average of 9.6 BCTs (range 1 to 28). The two most commonly used BCTs included 'problem-solving' and 'instruction on how to perform the behaviour'. Interventions varied in their type, content and mode of delivery. They included a problem-solving intervention; a paper-based self-management workbook; a telehealth intervention; a group training programme; a digital intervention comprising medication reminders and lung function self-monitoring; a life-coaching intervention; a motivational interviewing (MI) intervention; a brief MI intervention (behaviour change counselling); and a digital intervention combined with behaviour change sessions. Intervention duration ranged from 10 weeks to 12 months. Assessment time points ranged from six to eight weeks up to 23 months. Psychological interventions compared with usual care We report data here for the 'over six months and up to 12 months' time point. We found that psychological interventions probably improve adherence to inhaled therapies (primary outcome) in people with CF compared with usual care (mean difference (MD) 9.5, 95% confidence interval (CI) 8.60 to 10.40; 1 study, 588 participants; moderate-certainty evidence). There was no evidence of a difference between groups in our second primary outcome, treatment-related adverse events: anxiety (MD 0.30, 95% CI -0.40 to 1.00; 1 study, 535 participants), or depression (MD -0.10, 95% CI -0.80 to 0.60; 1 study, 534 participants), although this was low-certainty evidence. For our secondary outcomes, there was no evidence of a difference between groups in terms of lung function (forced expiratory volume in one second (FEV1) % predicted MD 1.40, 95% CI -0.20 to 3.00; 1 study, 556 participants; moderate-certainty evidence); number of pulmonary exacerbations (adjusted rate ratio 0.96, 95% CI 0.83 to 1.11; 1 study, 607 participants; moderate-certainty evidence); or respiratory symptoms (MD 0.70, 95% CI -2.40 to 3.80; 1 study, 534 participants; low-certainty evidence). However, psychological interventions may improve treatment burden (MD 3.90, 95% CI 1.20 to 6.60; 1 study, 539 participants; low-certainty evidence). The overall certainty of the evidence ranged from low to moderate across these outcomes. Reasons for downgrading included indirectness (current evidence included adults only whereas our review question was broader and focused on people of any age) and lack of blinding of outcome assessors. Psychological interventions compared with an active comparator For this comparison the overall certainty of evidence was very low, based on one trial (n = 128) comparing an MI intervention to EPS for 12 months. We are uncertain whether an MI intervention, compared with EPS, improves adherence to inhaled therapies, lung function, or quality of life in people with CF, or whether there is an effect on pulmonary exacerbations. The included trial for this comparison did not report on treatment-related adverse events (anxiety and depression). We downgraded all reported outcomes due to small participant numbers, indirectness (trials included only adults), and unclear risk of bias (e.g. selection and attrition bias).

AUTHORS' CONCLUSIONS

Due to the limited quantity of trials included in this review, as well as the clinical and methodological heterogeneity, it was not possible to identify an overall intervention effect using meta-analysis. Some moderate-certainty evidence suggests that psychological interventions (compared with usual care) probably improve adherence to inhaled therapies in people with CF, without increasing treatment-related adverse events, anxiety and depression (low-certainty evidence). In future review updates (with ongoing trial results included), we hope to be able to establish the most effective BCTs (or 'active ingredients') of interventions for improving adherence to inhaled therapies in people with CF. Wherever possible, investigators should make use of the most objective measures of adherence available (e.g. data-logging nebulisers) to accurately determine intervention effects. Outcome reporting needs to be improved to enable combining or separation of measures as appropriate. Likewise, trial reporting needs to include details of intervention content (e.g. BCTs used); duration; intensity; and fidelity. Large trials with a longer follow-up period (e.g. 12 months) are needed in children with CF. Additionally, more research is needed to determine how to support adherence in 'under-served' CF populations.

[Possibilities of using recombinant human deoxyribonuclease I in otorhinolaryngology]

ANNOTATION

Dornase alfa (Pulmozyme, Tigerase) is a purified solution of recombinant human DNase, clinically developed for the treatment of pulmonary diseases in patients with cystic fibrosis (CF). The action of the drug is aimed at destroying the viscous secretion, rich in DNA strands of neutrophils, through their fragmentation, the density of the secretion decreases, and the aeration of the lower respiratory tract improves. The similarity of pathological processes with the formation of viscous exudate on the surface of the mucous membrane in diseases of the upper respiratory tract and ear initiated studies on the use of Dornase alpha in otorhinolaryngology.

MATERIAL AND METHODS

The analysis of materials of domestic and foreign authors on the effectiveness of the use of the drug Dornase alfa in otorhinolaryngology was carried out.

RESULTS

The review included 132 patients (10 studies) in whom Dornase alfa was used to treat CF-associated nasal and paranasal sinus diseases. Analysis of the literature revealed only 3 studies, one of which consisted of two parts, examining the effect of Dornase alpha on middle ear exudate: two studies were demonstrated in an animal model; one - in vitro on samples of middle ear effusion which were aspirated through a myringotomy incision from patients with recurrent acute otitis media; and one in clinical 40 patients (40 ears) for hydrolysis of exudate in the tympanostomy tubes.

CONCLUSION

Analysis of studies on the use of Dornase alfa demonstrates an improvement in clinical symptoms in all patients with CF and chronic rhinosinusitis. In experimental studies on an animal model, as well as in vitro research on exudate from the middle ear, Dornase alfa has demonstrated high efficacy and safety. Dornase alfa is a drug with high potential, further research is needed for wider use in ENT practice, especially in otiatrics.

Physical Exercise Promotes DNase Activity Enhancing the Capacity to Degrade Neutrophil Extracellular Traps

(1) Background: An unhealthy lifestyle is a significant contributor to the development of chronic diseases. Physical activity can benefit primary and secondary prevention. Higher DNase activity is associated with favourable outcomes after cardiovascular (CV) events. In this study, we aimed to investigate the influence of consequent endurance exercise on DNase activity. (2) Methods: 98 subjects with at least one CV risk factor but the physical ability to perform endurance training were included. Individuals performed a bicycle stress test at the beginning and after 8 months to assess physical performance. In between, all participants were instructed to engage in guideline-directed physical activity. Blood samples were drawn in two-month intervals to assess routine laboratory parameters, cell-free DNA (cfDNA), and DNase activity. (3) Results: Prevailing CV risk factors were overweight (65.9%), a positive family history (44.9%), hypertension (32.7%) and smoking (20.4%). Performance changed by 7.8 ± 9.1% after 8 months. Comparison of baseline to 8 months revealed a decrease in cfDNA and an increase in DNase activity. This effect was driven by participants who achieved a performance gain. (4) Conclusions: Regular physical activity might improve CV health by increasing DNase activity and thereby, the capacity to lower pro-inflammatory signalling, complementing measures of primary and secondary prevention.

Effect of Dornase Alfa on the Lung Clearance Index in Children with Cystic Fibrosis: A Lesson from a Case Series

BACKGROUND

Dornase alfa (DNase) is the only mucus-degrading agent that has proven efficacy in cystic fibrosis (CF). Few studies have evaluated the effects of DNase on the lung clearance index (LCI). We report the experience of two CF centers in which LCI monitoring was used to evaluate the efficacy of DNase therapy.

METHODS

This is a prospective and observational study, evaluating the effects of DNase therapy on LCI values in three CF children followed at CF centers in Florence and Catania, Italy. In both centers, LCI was performed routinely, every 3-6 months, based on the clinical picture and severity of the lung disease. In this study, we evaluated the LCI before and after long-term DNase therapy.

RESULTS

DNase improved LCI values in the absence of respiratory exacerbations: in case n. 1 LCI decreased by 39% in 16 months (from 11.1 to 6.8); in case n. 2 by 20% in 12 months (from 9.3 to 7.4); in case n. 3 by 24% in 16 months (from 9.3 to 7.0).

CONCLUSIONS

This case series confirms the efficacy of DNase therapy in CF children, as demonstrated by the LCI reduction in treated patients. Furthermore, our results suggest that LCI is a sensitive marker of disease and can be used for the evaluation of response to treatment.

Dornase alfa in Cystic Fibrosis: indications, comparative studies and effects on lung clearance index

Cystic fibrosis (CF) is the most common inherited disease in Caucasian populations, affecting around 50,000 patients in Europe and 30,000 in United States. A mutation in CF trans-membrane conductance regulator (CFTR) gene changes a protein (a regulated chloride channel), which is expressed in many tissues. Defective CFTR results in reduced chloride secretion and an overage absorption of sodium across the epithelia, leading to thickened secretions in organs such as pancreas and lung. Gradually, there have been considerable improvements in the survival of people with CF, thanks to substantial changes in specialized CF care and the discovery of new CFTR modulators drugs. Nevertheless, lung disease remains the most common cause of death. For these reasons improvement of sputum clearance is a major therapeutic aim in CF. So far, symptomatic mucolytic therapy is mainly based on inhalation of dornase alfa, hypertonic saline or mannitol, in combination with physiotherapy. The major component of mucus in CF is pus including viscous material such as polymerized DNA derived from degraded neutrophils. Dornase alfa cleaves the DNA released from the neutrophils and reduces mucous viscosity, and further prevent airway infections and damage to the lung parenchyma. In this review we will summarize the current knowledge on dornase alfa in the treatment of CF lung disease, especially highlighting the positive effect on lung clearance index, a sensitive measure of ventilation inhomogeneity.

[Respiratory physiotherapy in pediatric practice]

Congestion of the upper (URT) and lower respiratory tracts (LRT) is a common symptom in several acute and chronic respiratory diseases that occur in childhood. To eliminate these secretions, airway clearance techniques (ACT) directed to the URT and LRT are frequently prescribed. The rationale for the application of these techniques is the same as in adults, but they need to be adapted to be transposed to children. The physiotherapist will be able to choose among a wide range of techniques, of which the most adequate will depend not only on the age of the child and the indication, but also on the basis of his preferences or habits, as well as those of the child. Upper airway clearance, including nasal irrigation, is now recommended for acute and chronic rhinosinusitis in children. It is also one of the symptomatic treatments recommended for infants with acute bronchiolitis. For LRT clearance, several indications, such as cystic fibrosis, primary ciliary dyskinesia and neuromuscular disease, are now widely advocated. Conversely, other indications, such as for infants with acute viral bronchiolitis, are highly controversial. Thoughtful application of these techniques is lacking in robust and precise tools to objectively assess the presence of bronchial congestion, and to treat it accordingly. Similarly, no precise and reliable evaluation of the effectiveness of these ACTs is available to date. This review is designed to explore the ACTs used by physiotherapists, to provide an overview of their current indications, and to consider complementary approaches.

Comparison of biosimilar Tigerase and Pulmozyme in long-term symptomatic therapy of patients with cystic fibrosis and severe pulmonary impairment (subgroup analysis of a Phase III randomized open-label clinical trial (NCT04468100))

Background

Patients with cystic fibrosis (CF) need costly medical care and adequate therapy with expensive medicinal products. Tigerase^® is the first biosimilar of dornase alfa, developed by the lead Russian biotechnology company GENERIUM. The aim of the manuscript to present post hoc sub-analysis of patients’ data with cystic fibrosis and severe pulmonary impairment of a larger comparative study (phase III open label, prospective, multi-centre, randomized study (NCT04468100)) of a generic version of recombinant human DNase Tigerase^® to the only comparable drug, Pulmozyme^®

Methods

In the analyses included subgroup of 46 severe pulmonary impairment patients with baseline FEV₁ level 40–60% of predicted (23 patients in each treatment group) out of 100 patients registered in the study phase III open label, prospective, multi-center, randomized study (NCT04468100), and compared efficacy endpoints (FEV₁, FVC, number and time of exacerbations, body weight, St.George’s Respiratory Questionnaire) as well as safety parameters (AEs, SAEs, anti-drug antibody) within 24 treatment weeks.

Results

All outcomes were comparable among the studied groups. In the efficacy dataset, the similar mean FEV₁ and mean FVC changes for 24 weeks of both treatment groups were observed. The groups were also comparable in safety, all the secondary efficacy parameters and immunogenicity.

Conclusions

The findings from this study support the clinical Tigerase^® biosimilarity to Pulmozyme^® administered in CF patients with severe impairment of pulmonary function.

Fundamentals in Covid-19-Associated Thrombosis: Molecular and Cellular Aspects

The novel coronavirus disease (COVID-19) is associated with a high incidence of coagulopathy and venous thromboembolism that may contribute to the worsening of the clinical outcome in affected patients. Marked increased D-dimer levels are the most common laboratory finding and have been repeatedly reported in critically ill COVID-19 patients. The infection caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is followed by a massive release of pro-inflammatory cytokines, which mediate the activation of endothelial cells, platelets, monocytes, and neutrophils in the vasculature. In this context, COVID-19-associated thrombosis is a complex process that seems to engage vascular cells along with soluble plasma factors, including the coagulation cascade, and complement system that contribute to the establishment of the prothrombotic state. In this review, we summarize the main findings concerning the cellular mechanisms proposed for the establishment of COVID-19-associated thrombosis.

Revisiting the Role of Leukocytes in Cystic Fibrosis

Cystic fibrosis in characterized by pulmonary bacterial colonization and hyperinflammation. Lymphocytes, monocytes/macrophages, neutrophils, and dendritic cells of patients with CF express functional CFTR and are directly affected by altered CFTR expression/function, impairing their ability to resolve infections and inflammation. However, the mechanism behind and the contribution of leukocytes in the pathogenesis of CF are still poorly characterized. The recent clinical introduction of specific CFTR modulators added an important tool not only for the clinical management of the disease but also to the investigation of the pathophysiological mechanisms related to CFTR dysfunction and dysregulated immunity. These drugs treat the basic defect in cystic fibrosis (CF) by increasing CFTR function with improvement of lung function and quality of life, and may improve clinical outcomes also by correcting the dysregulated immune function that characterizes CF. Measure of CFTR function, protein expression profiling and several omics methods were used to identify molecular changes in freshly isolated leukocytes of CF patients, highlighting two roles of leukocytes in CF: one more generally related to the mechanism(s) causing immune dysregulation in CF and unresolved inflammation, and another more applicative role, which identifies in myeloid cells, an important tool predictive of the therapeutic response of CF patients. In this review we will summarize available data on CFTR expression and function in leukocyte populations and will discuss potential clinical applications based on available data.

Patients with COVID-19: in the dark-NETs of neutrophils

SARS-CoV-2 infection poses a major threat to the lungs and multiple other organs, occasionally causing death. Until effective vaccines are developed to curb the pandemic, it is paramount to define the mechanisms and develop protective therapies to prevent organ dysfunction in patients with COVID-19. Individuals that develop severe manifestations have signs of dysregulated innate and adaptive immune responses. Emerging evidence implicates neutrophils and the disbalance between neutrophil extracellular trap (NET) formation and degradation plays a central role in the pathophysiology of inflammation, coagulopathy, organ damage, and immunothrombosis that characterize severe cases of COVID-19. Here, we discuss the evidence supporting a role for NETs in COVID-19 manifestations and present putative mechanisms, by which NETs promote tissue injury and immunothrombosis. We present therapeutic strategies, which have been successful in the treatment of immunο-inflammatory disorders and which target dysregulated NET formation or degradation, as potential approaches that may benefit patients with severe COVID-19.

Use of recombinant human deoxyribonuclease in pediatric intensive care unit - a single-center experience

OBJECTIVE

Dornase alfa (rhDNase) reduces the viscosity of purulent sputum in the lungs. The use in patients with cystic fibrosis (CF) is proven. However, the evidence of its applicability to other conditions is limited. This study aims to present the authors' experience with the use of rhDNase in non-CF patients admitted to the Pediatric Intensive Care Unit (PICU). At the study center, rhDNase was used during flexible bronchoscopies in 24 cases, of which 20 (83%) had atelectasis and seven (29%) were admitted to PICU. Four patients (57%) were on invasive mechanical ventilation (MV).

CASE DESCRIPTION

Two cases of daily rhDNase administration at PICU are presented: patient A was an 8-year-old boy admitted with septic shock and acute respiratory distress syndrome (ARDS). The patient required mechanical ventilation with aggressive settings and experienced several clinical complications. On D50, he started rhDNase treatment with an improvement in FiO2, PaCO2 and PaO2/FiO2 ratio according to radiologic findings. He was extubated on D23 of treatment.Patient B was a 17-month-old girl admitted with a convulsive status epilepticus who experienced respiratory complications (infectious and barotrauma) with ARDS, requiring aggressive ventilation. She initiated rhDNase treatment on D60. During the treatment an improvement in FiO2, PaO2/FiO2 ratio and a tendency of PaCO2 decrease were found. She had radiological improvement. No complications were described.

COMMENTS

RhDNase may be a helpful and safe tool to use in PICU prolonged intubated patients with ventilator-induced lung injury. Further studies are needed to assess and propose valid indications.

Hypertonic saline in people with cystic fibrosis: review of comparative studies and clinical practice

Cystic fibrosis (CF) is a multisystem disorder, caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. These cause a reduced secretion of chloride, a marked absorption of sodium and, therefore, of water, through the epithelium, resulting in the formation of thickened secretions in organs such as lung or pancreas. These viscous secretions lead to airway obstruction, chronic infection and inflammation resulting in progressive lung damage, bronchiectasis and eventual respiratory failure. Although the average life expectancy has increased over the last 30 years, lung disease is the most common cause of death in people with CF. For these reasons, the improvement of sputum clearance is a major therapeutic aim in CF and early initiation of airway clearance is widely recommended and implemented. Symptomatic mucolytic therapy today is mainly based on inhalation of DNase, hypertonic saline or mannitol, in combination with physiotherapy. Mucolytic agents break down the gel structure of mucus and therefore decrease its elasticity and viscosity, reducing the pulmonary exacerbation frequency and to improve and stabilize lung function. Nevertheless, high quality studies comparing these mucolytic drugs are still few, and the individual experiences of patients and caregivers explain the high variability of their use globally. This review will summarize the current knowledge on hypertonic saline in the treatment of CF lung disease. Furthermore, we report the real-world prescription of inhaled mucolytic agents in CF.

NETosis and the Immune System in COVID-19: Mechanisms and Potential Treatments

NETosis is a form of neutrophil death leading to the release of extracellular chromatin and the assembling of proteins, including antiviral proteins, primed by an initial pathogenic stimulus. Under certain specific conditions, neutrophils can exhibit a double-edged activity. This event has been implicated in COVID-19 among other conditions. Neutrophil extracellular traps (NETs) are involved in the pathogenesis of COVID-19 by promoting a pro-inflammatory and a procoagulant state leading to multiorgan failure. This particular form of host defense promoted by neutrophils is closely related to the well-known cytokine storm observed in severe COVID-19 patients. These two elements therefore represent possible targets for treatment of severe SARS-CoV-2 infections.

The Immune System Throws Its Traps: Cells and Their Extracellular Traps in Disease and Protection

The first formal description of the microbicidal activity of extracellular traps (ETs) containing DNA occurred in neutrophils in 2004. Since then, ETs have been identified in different populations of cells involved in both innate and adaptive immune responses. Much of the knowledge has been obtained from in vitro or ex vivo studies; however, in vivo evaluations in experimental models and human biological materials have corroborated some of the results obtained. Two types of ETs have been described—suicidal and vital ETs, with or without the death of the producer cell. The studies showed that the same cell type may have more than one ETs formation mechanism and that different cells may have similar ETs formation mechanisms. ETs can act by controlling or promoting the mechanisms involved in the development and evolution of various infectious and non-infectious diseases, such as autoimmune, cardiovascular, thrombotic, and neoplastic diseases, among others. This review discusses the presence of ETs in neutrophils, macrophages, mast cells, eosinophils, basophils, plasmacytoid dendritic cells, and recent evidence of the presence of ETs in B lymphocytes, CD4+ T lymphocytes, and CD8+ T lymphocytes. Moreover, due to recently collected information, the effect of ETs on COVID-19 is also discussed.

Inadequate Functioning of Nebulizer System Compressors Used by Individuals With Cystic Fibrosis

BACKGROUND

The treatment of cystic fibrosis involves the use of drugs delivered by nebulizer systems, and adequate functioning of the compressors and nebulizers is essential. We hypothesized that compressors of nebulizer systems used by individuals with cystic fibrosis would not work properly. Therefore, we aimed to assess the performance of the compressors from nebulizer systems used by individuals with cystic fibrosis.

METHODS

This is a cross-sectional study to assess the performance of compressors from nebulizer systems used by subjects with cystic fibrosis registered at the Cystic Fibrosis Patient Association in Minas Gerais, Brazil. Compressors (Proneb Ultra II) brought by the individuals were tested with new nebulizer parts (Pari LC plus) to assess the variables of nebulization efficiency, including residual volume, solution output, and aerosol output rate. Compression performance was assessed by measuring the operating pressure using a PARI PG101 manometer.

RESULTS

The performance of 146 compressors was analyzed. Fifty-seven (39%) of the compressors were ineffective, with operating pressure values well below the manufacturer's technical reference and the compressor time used for a median time of 36 (15 days to 156 months). The systems with low pressure values demonstrated significantly worse results for nebulization efficiency variables, and a significant correlation was found between residual volume (r = -0.5, P < .001), solution output (r = +0.5, P < .001), and aerosol output rate (r = +0.5, P < .001), and operating pressure values.

CONCLUSIONS

A significant number of compressors generate low operating pressure values. These systems showed a compromised efficiency of nebulization, indicating that the pressure generated by the compressor is a critical aspect of treatment efficiency.

COVID-19 pathophysiology and pharmacology: what do we know and how did Canadians respond? A review of Health Canada authorized clinical vaccine and drug trials

Coronavirus disease 2019 (COVID-19) has resulted in the death of over 18 000 Canadians and has impacted the lives of all Canadians. Many Canadian research groups have expanded their research programs to include COVID-19. Over the past year, our knowledge of this novel disease has grown and has led to the initiation of a number of clinical vaccine and drug trials for the prevention and treatment of COVID-19. Here, we review SARS-CoV-2 (the coronavirus that causes COVID-19) and the natural history of COVID-19, including a timeline of disease progression after SARS-CoV-2 exposure. We also review the pathophysiological effects of COVID-19 on the organ systems that have been implicated in the disease, including the lungs, upper respiratory tract, immune system, central nervous system, cardiovascular system, gastrointestinal organs, the liver, and the kidneys. Then we review general therapeutics strategies that are being applied and investigated for the prevention or treatment of COVID-19, including vaccines, antivirals, immune system enhancers, pulmonary supportive agents, immunosuppressants and (or) anti-inflammatories, and cardiovascular system regulators. Finally, we provide an overview of all current Health Canada authorized clinical drug and vaccine trials for the prevention or treatment of COVID-19.

Dornase alfa for cystic fibrosis

BACKGROUND

Dornase alfa is currently used as a mucolytic to treat pulmonary disease (the major cause of morbidity and mortality) in cystic fibrosis. It reduces mucus viscosity in the lungs, promoting improved clearance of secretions. This is an update of a previously published review.

OBJECTIVES

To determine whether the use of dornase alfa in cystic fibrosis is associated with improved mortality and morbidity compared to placebo or other medications that improve airway clearance, and to identify any adverse events associated with its use.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches, handsearching relevant journals and abstracts from conferences. Date of the most recent search of the Group's Cystic Fibrosis Register: 12 October 2020. Clinicaltrials.gov and the International Clinical Trials Registry Platform were also searched to identify unpublished or ongoing trials. Date of most recent search: 08 February 2021.

SELECTION CRITERIA

All randomised and quasi-randomised controlled trials comparing dornase alfa to placebo, standard therapy or other medications that improve airway clearance.

DATA COLLECTION AND ANALYSIS

Authors independently assessed trials against the inclusion criteria; two authors carried out analysis of methodological quality and data extraction. GRADE was used to assess the level of evidence.

MAIN RESULTS

The searches identified 74 trials, of which 19 (2565 participants) met our inclusion criteria. 15 trials compared dornase alfa to placebo or no dornase alfa (2447 participants); two compared daily dornase to hypertonic saline (32 participants); one compared daily dornase alfa to hypertonic saline and alternate day dornase alfa (48 participants); one compared dornase alfa to mannitol and the combination of both drugs (38 participants). Trial duration varied from six days to three years. Dornase alfa compared to placebo or no treatment Dornase alfa probably improved forced expiratory volume at one second (FEV1) at one month (four trials, 248 participants), three months (one trial, 320 participants; moderate-quality evidence), six months (one trial, 647 participants; high-quality evidence) and two years (one trial, 410 participants). Limited low-quality evidence showed treatment may make little or no difference  in quality of life. Dornase alfa probably reduced the number of pulmonary exacerbations in trials of up to two years (moderate-quality evidence). One trial that examined the cost of care, including the cost of dornase alfa, found that the cost savings from dornase alfa offset 18% to 38% of the medication costs. Dornase alfa: daily versus alternate day One cross-over trial (43 children) found little or no difference between treatment regimens for lung function, quality of life or pulmonary exacerbations (low-quality evidence). Dornase alfa compared to other medications that improve airway clearance Results for these comparisons were mixed. One trial (43 children) showed dornase alfa may lead to a greater improvement in FEV1 compared to hypertonic saline (low-quality evidence), and one trial (23 participants) reported little or no differences in lung function between dornase alfa and mannitol or dornase alfa and dornase alfa plus mannitol (low-quality evidence). One trial (23 participants) found dornase alfa may improve quality of life compared to dornase alfa plus mannitol (low-quality evidence); other comparisons found little or no difference in this outcome (low-quality evidence). No trials in any comparison reported any difference between groups in the number of pulmonary exacerbations (low-quality evidence). When all comparisons are assessed, dornase alfa did not cause significantly more adverse effects than other treatments, except voice alteration and rash.

AUTHORS' CONCLUSIONS

There is evidence to show that, compared with placebo, therapy with dornase alfa may improve lung function in people with cystic fibrosis in trials lasting from one month to two years. There was a decrease in pulmonary exacerbations in trials of six months or longer, probably due to treatment. Voice alteration and rash appear to be the only adverse events reported with increased frequency in randomised controlled trials. There is not enough evidence to firmly conclude if dornase alfa is superior to other hyperosmolar agents in improving lung function.

Timing of dornase alfa inhalation for cystic fibrosis

BACKGROUND

Inhalation of the enzyme dornase alfa reduces sputum viscosity and improves clinical outcomes of people with cystic fibrosis. This is an update of a previously published Cochrane Review.

OBJECTIVES

To determine whether the timing of dornase alfa inhalation (in relation to airway clearance techniques or morning versus evening inhalation) has an impact on objective and subjective measures of clinical efficacy in people with cystic fibrosis.

SEARCH METHODS

Relevant randomised and quasi-randomised controlled trials were identified from the Cochrane Cystic Fibrosis Trials Register, the Physiotherapy Evidence Database (PEDro), clinical trial registries and international cystic fibrosis conference proceedings. Date of the most recent search: 12 October 2020.

SELECTION CRITERIA

Any trial of dornase alfa in people with cystic fibrosis where timing of inhalation was the randomised element in the trial with either: inhalation before compared to after airway clearance techniques; or morning compared to evening inhalation.  DATA COLLECTION AND ANALYSIS: Both authors independently selected trials, assessed risk of bias and extracted data with disagreements resolved by discussion. Relevant data were extracted and, where possible, meta-analysed. We assessed the quality of the evidence using GRADE.

MAIN RESULTS

We identified 115 trial reports representing 55 trials, of which five trials (providing data on 122 participants) met our inclusion criteria. All five trials used a cross-over design. Intervention periods ranged from two to eight weeks. Four trials (98 participants) compared dornase alfa inhalation before versus after airway clearance techniques. Inhalation after instead of before airway clearance did not significantly change forced expiratory volume at one second (very-low quality evidence). Similarly, forced vital capacity (low-quality evidence) and quality of life (very-low quality evidence) were not significantly affected; forced expiratory flow at 25% was significantly worse with dornase alfa inhalation after airway clearance, mean difference -0.17 litres (95% confidence interval -0.28 to -0.05), based on the pooled data from two small trials in children (7 to 19 years) with well-preserved lung function. All other secondary outcomes were statistically non-significant. In one trial (25 participants), morning versus evening inhalation had no impact on lung function or symptoms (low-quality evidence).

AUTHORS' CONCLUSIONS

The current evidence derived from a small number of participants does not indicate that inhalation of dornase alfa after airway clearance techniques is more or less effective than the traditional recommendation to inhale nebulised dornase alfa 30 minutes prior to airway clearance techniques, for most outcomes. For children with well-preserved lung function, inhalation before airway clearance may be more beneficial for small airway function than inhalation after. However, this result relied on a measure with high variability and trials with variable follow-up. In the absence of strong evidence to indicate that one timing regimen is better than another, the timing of dornase alfa inhalation can be largely based on pragmatic reasons or individual preference with respect to the time of airway clearance and time of day. Further research is warranted.

Pulmonary Exacerbations in Adults With Cystic Fibrosis: A Grown-up Issue in a Changing Cystic Fibrosis Landscape

Pulmonary exacerbations (PExs) are significant life events in people with cystic fibrosis (CF), associated with declining lung function, reduced quality of life, hospitalizations, and decreased survival. The adult CF population is increasing worldwide, with many patients surviving prolonged periods with severe multimorbid disease. In many countries, the number of adults with CF exceeds the number of children, and PExs are particularly burdensome for adults as they tend to require longer courses and more IV treatment than children. The approach to managing PExs is multifactorial and needs to evolve to reflect this changing adult population. This review discusses PEx definitions, precipitants, treatments, and the wider implications to health-care resources. It reviews current management strategies, their relevance in particular to adults with CF, and highlights some of the gaps in our knowledge. A number of studies are underway to try to answer some of the unmet needs, such as the optimal length of treatment and the use of nonantimicrobial agents alongside antibiotics. An overview of these issues is provided, concluding that with the changing landscape of adult CF care, the definitions and management of PExs may need to evolve to enable continued improvements in outcomes across the age spectrum of CF.

Real-World Safety of CFTR Modulators in the Treatment of Cystic Fibrosis: A Systematic Review

Cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies target the underlying cause of cystic fibrosis (CF), and are generally well-tolerated; however, real-world studies indicate the frequency of discontinuation and adverse events (AEs) may be higher than what was observed in clinical trials. The objectives of this systematic review were to summarize real-world AEs reported for market-available CFTR modulators (i.e., ivacaftor (IVA), lumacaftor/ivacaftor (LUM/IVA), tezacaftor/ivacaftor (TEZ/IVA), and elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA)), and to identify ways in which the pharmacist on CF healthcare teams may contribute to mitigating and managing these AEs. The MEDLINE, EMBASE, CINAHL, and Web of Science Core Collection online databases were searched from 2012 to 1 Aug 2020. Full manuscripts or conference abstracts of observational studies, case series, and case reports were eligible for inclusion. The included full manuscripts and conference abstracts comprised of 54 observational studies, 5 case series, and 9 case reports. The types of AEs reported generally aligned with what have been observed in clinical trials. LUM/IVA was associated with a higher frequency of respiratory-related AE and discontinuation in real-world studies. A signal for mental health and neurocognitive AEs was identified with all 4 CFTR modulators. A systematic approach to monitoring for AEs in people with CF on CFTR modulators in the real-world setting is necessary to help better understand potential AEs, as well as patient characteristics that may be associated with higher risk of certain AEs. Pharmacists play a key role in the safe initiation and monitoring of people with CF on CFTR modulator therapies.

Airway Redox Homeostasis and Inflammation Gone Awry: From Molecular Pathogenesis to Emerging Therapeutics in Respiratory Pathology

As aerobic organisms, we are continuously and throughout our lifetime subjected to an oxidizing atmosphere and, most often, to environmental threats. The lung is the internal organ most highly exposed to this milieu. Therefore, it has evolved to confront both oxidative stress induced by reactive oxygen species (ROS) and a variety of pollutants, pathogens, and allergens that promote inflammation and can harm the airways to different degrees. Indeed, an excess of ROS, generated intrinsically or from external sources, can imprint direct damage to key structural cell components (nucleic acids, sugars, lipids, and proteins) and indirectly perturb ROS-mediated signaling in lung epithelia, impairing its homeostasis. These early events complemented with efficient recognition of pathogen- or damage-associated recognition patterns by the airway resident cells alert the immune system, which mounts an inflammatory response to remove the hazards, including collateral dead cells and cellular debris, in an attempt to return to homeostatic conditions. Thus, any major or chronic dysregulation of the redox balance, the air-liquid interface, or defects in epithelial proteins impairing mucociliary clearance or other defense systems may lead to airway damage. Here, we review our understanding of the key role of oxidative stress and inflammation in respiratory pathology, and extensively report current and future trends in antioxidant and anti-inflammatory treatments focusing on the following major acute and chronic lung diseases: acute lung injury/respiratory distress syndrome, asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, and cystic fibrosis.

[Evidence-based treatment of cystic fibrosis]

Mucoviscidosis (cystic fibrosis [CF]) is the most common autosomal recessive inherited multisystem disease with fatal outcome. It is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to a dysfunctional chloride channel and a defective CFTR protein. As a consequence, retention of insufficiently hydrated mucus affects multiple essential organs, mainly the lungs and airways, pancreas, liver, biliary tract and intestines. This leads to inflammation and infection, fibrosis and progressive tissue destruction. Respiratory failure is the major cause of mortality; however, in the no more than 30 years since the molecular characterization of the basic CFTR defect causing CF, tremendous success has been made with respect to the long-term prognosis of people with CF. This improvement in the prognosis was achieved by the cooperative spirit and networking of the very active and international CF research community and by establishing a multidisciplinary clinical CF team that implements the existing evidence in various aspects of standardized care together with the CF patient. This narrative review article presents the evidence in selected aspects of CF treatment, with special consideration of the most recent development of highly effective CFTR modulator treatment. This treatment will soon become available for more than 90% of the global CF patients and transform the pathophysiology as well as the course of disease towards a treatable chronic condition in internal medicine.

Observations of, and Insights into, Cystic Fibrosis Mucus Heterogeneity in the Pre-Modulator Era: Sputum Characteristics, DNA and Glycoprotein Content, and Solubilization Time

Airway obstruction with chronic inflammation and infection are major contributors to the lung damage and mortality of cystic fibrosis (CF). A better understanding of the congested milieu of CF airways will aid in improving therapeutic strategies. This article retrospectively reports our observations, and discusses insights gained in the handling and analysis of CF sputa. CF and non-CF mucus samples were surveyed for morphological features by electron microscopy and analyzed for the macromolecular dry weight (MDW), total protein, lipid, carbohydrate, and DNA. Mucus character was investigated with chemical solubilization time as a comparative tool. CF mucus appeared distinctly thick, viscous, and heterogeneous, with neutrophils as the dominant immune cell. CF sputum DNA content varied markedly for and between individuals (~1–10% MDW), as did solubilization times (~1–20 h). CF Sputum DNA up to 7.1% MDW correlated positively with solubilization time, whereas DNA >7.1% MDW correlated negatively. 3D analysis of CF sputa DNA, GP, and solubilization times revealed a dynamic and predictive relationship. Reflecting on the heterogeneous content and character of CF mucus, and the possible interplay in space and time in the respiratory tract of polymeric DNA and mucous glycoproteins, we highlight it’s potential to affect infection-related airway pathologies and the success of therapeutic interventions.

The emerging role of neutrophil extracellular traps in severe acute respiratory syndrome coronavirus 2 (COVID-19)

The novel coronavirus SARS-CoV-2 causes COVID-19, a highly pathogenic viral infection threatening millions. The majority of the individuals infected are asymptomatic or mildly symptomatic showing typical clinical signs of common cold. However, approximately 20% of the patients can progress to acute respiratory distress syndrome (ARDS), evolving to death in about 5% of cases. Recently, angiotensin-converting enzyme 2 (ACE2) has been shown to be a functional receptor for virus entry into host target cells. The upregulation of ACE2 in patients with comorbidities may represent a propensity for increased viral load and spreading of infection to extrapulmonary tissues. This systemic infection is associated with higher neutrophil to lymphocyte ratio in infected tissues and high levels of pro-inflammatory cytokines leading to an extensive microthrombus formation with multiorgan failure. Herein we investigated whether SARS-CoV-2 can stimulate extracellular neutrophils traps (NETs) in a process called NETosis. We demonstrated for the first time that SARS-CoV-2 in fact is able to activate NETosis in human neutrophils. Our findings indicated that this process is associated with increased levels of intracellular Reactive Oxygen Species (ROS) in neutrophils. The ROS-NET pathway plays a role in thrombosis formation and our study suggest the importance of this target for therapy approaches against disease.

Mechanisms of Action of a Web-Based Intervention With Health Professional Support to Increase Adherence to Nebulizer Treatments in Adults With Cystic Fibrosis: Qualitative Interview Study

Background

Adherence to nebulizer treatments in adults with cystic fibrosis (CF) is often low. A new complex intervention to help adults with CF increase their adherence to nebulizer treatments was tested in a pilot randomized controlled trial (RCT) in 2 UK CF centers. Patients used a nebulizer with electronic monitoring capabilities that transferred data automatically to a digital platform (CFHealthHub) to monitor adherence over time and to a tailored website to display graphs of adherence data and educational and problem-solving information about adherence. A trained interventionist helped patients identify ways to increase their adherence.

Objective

This study aims to explore the mechanisms of action underpinning the intervention.

Methods

A qualitative interview study was conducted concurrently with a pilot RCT. In total, 25 semistructured interviews were conducted with 3 interventionists at 2 time points, 14 patients in the intervention arm of the trial, and 5 members of the multidisciplinary teams offering wider care to patients. A framework approach was used for the analysis.

Results

The intervention was informed by a theoretical framework of behavior change. There was evidence of the expected behavior change mechanisms of action. There was also evidence of additional mechanisms of action associated with effective telehealth interventions for self-management support: relationships, visibility, and fit. Patients described how building a relationship with the interventionist through face-to-face visits with someone who cared about them and their progress helped them to consider ways of increasing adherence to medication. Rather than seeing the visibility of adherence data to clinicians as problematic, patients found this motivating, particularly if they received praise about progress made. The intervention was tailored to individuals, but there were challenges in how the intervention fitted into some patients’ busy lives when delivered through a desktop computer.

Conclusions

The mechanisms of action associated with effective telehealth interventions for self-management operated within this new intervention. The intervention was modified to strengthen mechanisms of action based on these findings, for example, delivery through an app accessed via mobile phones and then tested in an RCT in 19 UK CF centers.

Trial Registration

International Standard Randomized Controlled Trial Number 13076797; http://www.isrctn.com/ISRCTN13076797

Nebulized in-line endotracheal dornase alfa and albuterol administered to mechanically ventilated COVID-19 patients: a case series

Background

Mechanically ventilated patients with COVID-19 have a mortality of 24–53%, in part due to distal mucopurulent secretions interfering with ventilation. DNA from neutrophil extracellular traps (NETs) contribute to the viscosity of mucopurulent secretions and NETs are found in the serum of COVID-19 patients. Dornase alfa is recombinant human DNase 1 and is used to digest DNA in mucoid sputum. Here, we report a single-center case series where dornase alfa was co-administered with albuterol through an in-line nebulizer system.

Methods

Demographic and clinical data were collected from the electronic medical records of five mechanically ventilated patients with COVID-19—including three requiring veno-venous extracorporeal membrane oxygenation—treated with nebulized in-line endotracheal dornase alfa and albuterol, between March 31 and April 24, 2020. Data on tolerability and response were analyzed.

Results

The fraction of inspired oxygen requirements was reduced for all five patients after initiating dornase alfa administration. All patients were successfully extubated, discharged from hospital and remain alive. No drug-associated toxicities were identified.

Conclusions

Results suggest that dornase alfa will be well-tolerated by patients with severe COVID-19. Clinical trials are required to formally test the dosing, safety, and efficacy of dornase alfa in COVID-19, and several have been recently registered.

Access to medicines for rare diseases: beating the drum for primary ciliary dyskinesia

Rare diseases are collectively common, affecting an estimated 6.2% of the world's population [1], but each rare disease affects fewer than 4 to 5 in 10 000 individuals in Europe or less than 200 000 individuals in the USA [2]. Patients with rare diseases are often disadvantaged by late diagnosis and off-label prescribing of medicines [3]. Primary ciliary dyskinesia (PCD) is a genetic disease of impaired motile ciliary function that does not have a unique International Classification of Diseases (ICD)-10 code or licensed treatments, although Q34.8 denoting “other specified malformations of the respiratory tract” including nasopharyngeal atresia has also been applicable to PCD since 2017. The disease is characterised by mucus stagnation leading to chronic airway infection, bronchiectasis, chronic rhinosinusitis, reduced fertility and abnormalities of organ laterality with an associated increased risk of complex congenital heart disease [4]. The estimated prevalence of PCD in Europe is around 1 in 10 000 to 1 in 20 000 [5]. The international PCD cohort (iPCD) includes over 3800 PCD patients ranging in age from under 12 months to over 80 years, from Europe, Northern and Southern America, Australia and Western Asia [6]. Under-diagnosis of PCD is due to a lack of awareness among the general public and physicians in general, as well as a lack of diagnostic expertise in some countries [7]. Tools to help physicians identify patients needing testing (e.g. PICADAR) [8] and the European Respiratory Society (ERS) guidelines for diagnostic testing [9] aim to improve this. In contrast to cystic fibrosis (CF), a monogenic disease, PCD is caused by mutations in one of at least 45 identified genes for which there is no effective mutation-specific therapy; this is likely to be a long way off for most patients [10]. Thus, treatment aims to prevent and manage disease complications. Even then, the lack of an evidence base for supportive treatment in PCD means that treatment recommendations are based on expert opinion and extrapolated from CF despite differing pathophysiology [11].

Primary ciliary dyskinesia, a rare disease causing bronchiectasis, lacks a sound evidence base for treatment. @beatpcd proposes 1) forming a PCD European clinical trial network to address this situation and 2) conducting n-of-1 trials to access medication.https://bit.ly/3j5blfM

Preliminary report of in vitro and in vivo effectiveness of dornase alfa on SARS-CoV-2 infection

Dornase alfa, the recombinant form of the human DNase I enzyme, breaks down neutrophil extracellular traps (NET) that include a vast amount of DNA fragments, histones, microbicidal proteins and oxidant enzymes released from necrotic neutrophils in the highly viscous mucus of cystic fibrosis patients. Dornase alfa has been used for decades in patients with cystic fibrosis to reduce the viscoelasticity of respiratory tract secretions, to decrease the severity of respiratory tract infections, and to improve lung function. Previous studies have linked abnormal NET formations to lung diseases, especially to acute respiratory distress syndrome (ARDS). It is well known that novel coronavirus disease 2019 (COVID-19) pneumonia progresses to ARDS and even multiple organ failure. High blood neutrophil levels are an early indicator of COVID-19 and predict severe respiratory diseases. Also it is reported that mucus structure in COVID-19 is very similar to that in cystic fibrosis due to the accumulation of excessive NET in the lungs. In this study, we showed the recovery of three individuals with COVID-19 after including dornase alfa in their treatment. We followed clinical improvement in the radiological analysis (two of three cases), oxygen saturation (Spo₂), respiratory rate, disappearance of dyspnoea, coughing and a decrease in NET formation and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load after the treatment. Also here, we share our preliminary results suggesting that dornase alfa has an anti-viral effect against SARS-CoV-2 infection in a green monkey kidney cell line, Vero, and a bovine kidney cell line, MDBK, without determined cytotoxicity on healthy peripheral blood mononuclear cells.

COVID-19 and immunological regulations - from basic and translational aspects to clinical implications

The COVID‐19 pandemic caused by SARS‐CoV‐2 has far‐reaching direct and indirect medical consequences. These include both the course and treatment of diseases. It is becoming increasingly clear that infections with SARS‐CoV‐2 can cause considerable immunological alterations, which particularly also affect pathogenetically and/or therapeutically relevant factors.

Against this background we summarize here the current state of knowledge on the interaction of SARS‐CoV‐2/COVID‐19 with mediators of the acute phase of inflammation (TNF, IL‐1, IL‐6), type 1 and type 17 immune responses (IL‐12, IL‐23, IL‐17, IL‐36), type 2 immune reactions (IL‐4, IL‐13, IL‐5, IL‐31, IgE), B‐cell immunity, checkpoint regulators (PD‐1, PD‐L1, CTLA4), and orally druggable signaling pathways (JAK, PDE4, calcineurin). In addition, we discuss in this context non‐specific immune modulation by glucocorticosteroids, methotrexate, antimalarial drugs, azathioprine, dapsone, mycophenolate mofetil and fumaric acid esters, as well as neutrophil granulocyte‐mediated innate immune mechanisms.

From these recent findings we derive possible implications for the therapeutic modulation of said immunological mechanisms in connection with SARS‐CoV‐2/COVID‐19. Although, of course, the greatest care should be taken with patients with immunologically mediated diseases or immunomodulating therapies, it appears that many treatments can also be carried out during the COVID‐19 pandemic; some even appear to alleviate COVID‐19.

COVID‐19 und Immunregulation – von grundlegenden und translationalen Aspekten zu klinischen Implikationen

Die durch SARS‐CoV‐2 verursachte Pandemie COVID‐19 hat weitreichende direkte und indirekte medizinische Folgen. Dazu gehören sowohl der Verlauf als auch die Behandlung vieler Krankheiten. Es wird immer deutlicher, dass Infektionen mit SARS‐CoV‐2 erhebliche immunologische Veränderungen verursachen können, die insbesondere auch pathogenetisch und/oder therapeutisch relevante Faktoren betreffen.

Vor diesem Hintergrund fassen wir hier den aktuellen Wissensstand zur Interaktion von SARS‐CoV‐2/COVID‐19 mit Mediatoren der akuten Phase der Entzündung (TNF, IL‐1, IL‐6), der Typ‐1‐ und Typ‐17‐Immunantwort (IL‐12, IL‐23, IL‐17, IL‐36), Typ‐2‐Immunreaktionen (IL‐4, IL‐13, IL‐5, IL‐31, IgE), B‐Zell‐Immunität, Checkpoint‐Regulatoren (PD‐1, PD‐L1, CTLA4) und Signalwegen, die durch oral applizierte Medikamente moduliert werden (JAK, PDE4, Calcineurin), zusammen. Darüber hinaus diskutieren wir in diesem Zusammenhang die unspezifische Immunmodulation durch Glukokortikosteroide, Methotrexat, Malariamittel, Azathioprin, Dapson, Mycophenolsäure‐Derivate und Fumarsäureester sowie angeborene Immunmechanismen neutrophiler Granulozyten.

Aus diesen neueren Erkenntnissen leiten wir mögliche Implikationen für die therapeutische Modulation der genannten immunologischen Mechanismen im Zusammenhang mit SARS‐CoV‐2/COVID‐19 ab. Obwohl natürlich bei Patienten mit immunologisch vermittelten Krankheiten oder immunmodulierenden Therapien größte Vorsicht geboten ist, scheint es, dass viele Behandlungen auch während der COVID‐19‐Pandemie durchgeführt werden können; einige scheinen COVID‐19 sogar zu lindern.

Novel Anti-Inflammatory Approaches for Cystic Fibrosis Lung Disease: Identification of Molecular Targets and Design of Innovative Therapies

Cystic fibrosis (CF) is the most common genetic disorder among Caucasians, estimated to affect more than 70,000 people in the world. Severe and persistent bronchial inflammation and chronic bacterial infection, along with airway mucus obstruction, are hallmarks of CF lung disease and participate in its progression. Anti-inflammatory therapies are, therefore, of particular interest for CF lung disease. Furthermore, a better understanding of the molecular mechanisms involved in airway infection and inflammation in CF has led to the development of new therapeutic approaches that are currently under evaluation by clinical trials. These new strategies dedicated to CF inflammation are designed to treat different dysregulated aspects such as oxidative stress, cytokine secretion, and the targeting of dysregulated pathways. In this review, we summarize the current understanding of the cellular and molecular mechanisms that contribute to abnormal lung inflammation in CF, as well as the new anti-inflammatory strategies proposed to CF patients by exploring novel molecular targets and novel drug approaches.

Cutaneous sıde-effects of the potential COVID-19 drugs

COVID‐19 disease is a highly contagious and particularly popular problem in all countries. A variety of repurposed drugs and investigational drugs such as remdesivir, chloroquine, hydroxychloroquine, ritonavir, lopinavir, interferon‐beta, and other potential drugs have been studied for COVID19 treatment. We reviewed the potential dermatological side‐effects of these drugs.

Nebulized in-line endotracheal dornase alfa and albuterol administered to mechanically ventilated COVID-19 patients: A case series

Background

Mechanically ventilated patients with coronavirus disease 2019 (COVID-19) have a mortality of 24–53%, in part due to distal mucopurulent secretions interfering with ventilation. Dornase alfa is recombinant human DNase 1 and digests DNA in mucoid sputum. Nebulized dornase alfa is FDA-approved for cystic fibrosis treatment. DNA from neutrophil extracellular traps (NETs) contributes to the viscosity of mucopurulent secretions. NETs are found in the serum of patients with severe COVID-19, and targeting NETs reduces mortality in animal models of acute respiratory distress syndrome (ARDS). Thus, dornase alfa may be beneficial to patients with severe COVID-19—acting as a mucolytic and targeting NETs. However, delivery of nebulized drugs can aerosolize SARS-CoV-2, which causes COVID-19, increasing the infection risk for staff. Here, we report a single center case series where dornase alfa was administered through an in-line nebulizer system to minimize risk of virus aerosolization.

Methods

Demographic, clinical data, and outcomes were collected from the electronic medical records of five mechanically ventilated patients with COVID-19—including three requiring veno-venous extracorporeal membrane oxygenation (VV-ECMO)—treated with nebulized in-line endotracheal dornase alfa co-administered with albuterol (used to increase delivery to the alveoli), between March 31 and April 24, 2020. Data on tolerability and responses, including longitudinal values capturing respiratory function and inflammatory status, were analyzed.

Results

Following nebulized in-line administration of dornase alfa with albuterol, the fraction of inspired oxygen requirements was reduced for all five patients. All patients remain alive and two patients have been discharged from the intensive care unit. No drug associated toxicities were identified.

Conclusions

The results presented in this case series suggest that dornase alfa will be well-tolerated by critically ill patients with COVID-19. Clinical trials are required to formally test the dosing, safety, and efficacy of dornase alfa in COVID-19, and two have recently been registered (NCT04359654 and NCT04355364). With this case series, we hope to contribute to the development of management approaches for critically ill patients with COVID-19.

Mucoactive agent use in adult UK Critical Care Units: a survey of health care professionals' perception, pharmacists' description of practice, and point prevalence of mucoactive use in invasively mechanically ventilated patients

Background

Mechanical ventilation for acute respiratory failure is one of the most common indications for admission to intensive care units (ICUs). Airway mucus clearance is impaired in these patients medication, impaired mucociliary motility, increased mucus production etc. and mucoactive agents have the potential to improve outcomes. However, studies to date have provided inconclusive results. Despite this uncertainty, mucoactives are used in adult ICUs, although the extent of use and perceptions about place in therapy are not known.

Aims and Objectives

We aim to describe the use of mucoactive agents in mechanically ventilated patients in UK adult critical care units. Specifically, our objectives are to describe clinicians perceptions about the use of mucoactive agents, understand the indications and anticipated benefits, and describe the prevalence and type of mucoactive agents in use.

Methods

We conducted three surveys. Firstly, a practitioner-level survey aimed at nurses, physiotherapists and doctors to elucidate individual practitioners perceptions about the use of mucoactive agents. Secondly, a critical care unit-level survey aimed at pharmacists to understand how these perceptions translate into practice. Thirdly, a point prevalence survey to describe the extent of prescribing and range of products in use. The practitioner-level survey was disseminated through the UK Intensive Care Society for completion by a multi-professional membership. The unit-level and point prevalence surveys were disseminated cthrough the UK Clinical Pharmacy Association for completion by pharmacists.

Results

The individual practitioners survey ranked ‘thick secretions’ as the main reason for commencing mucoactive agents determined using clinical assessment. The highest ranked perceived benefit for patient centred outcomes was the duration of ventilation. Of these respondents, 79% stated that further research was important and 87% expressed support for a clinical trial. The unit-level survey found that mucoactive agents were used in 83% of units. The most highly ranked indication was again ‘thick secretions’ and the most highly ranked expected patient centred clinical benefit being improved gas exchange and reduced ventilation time. Only five critical care units provided guidelines to direct the use of mucoactive agents (4%). In the point prevalence survey, 411/993 (41%) of mechanically ventilated patients received at least one mucoactive agent. The most commonly administered mucoactives were inhaled sodium chloride 0.9% (235/993, 24%), systemic carbocisteine (161/993, 16%) and inhaled hypertonic sodium cloride (127/993, 13%).

Conclusions

Mucoactive agents are used extensively in mechanically ventilated adult patients in UK ICUs to manage ‘thick secretions’, with a key aim to reduce the duration of ventilation. There is widespread support for clinical trials to determine the optimal use of mucoactive agent therapy in this patient population.

Inhaled mannitol for cystic fibrosis

BACKGROUND

Several agents are used to clear secretions from the airways of people with cystic fibrosis. Mannitol increases mucociliary clearance, but its exact mechanism of action is unknown. The dry powder formulation of mannitol may be more convenient and easier to use compared with established agents which require delivery via a nebuliser. Phase III trials of inhaled dry powder mannitol for the treatment of cystic fibrosis have been completed and it is now available in Australia and some countries in Europe. This is an update of a previous review.

OBJECTIVES

To assess whether inhaled dry powder mannitol is well tolerated, whether it improves the quality of life and respiratory function in people with cystic fibrosis and which adverse events are associated with the treatment.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic databases, handsearching relevant journals and abstracts from conferences. Date of last search: 12 December 2019.

SELECTION CRITERIA

All randomised controlled studies comparing mannitol with placebo, active inhaled comparators (for example, hypertonic saline or dornase alfa) or with no treatment.

DATA COLLECTION AND ANALYSIS

Authors independently assessed studies for inclusion, carried out data extraction and assessed the risk of bias in included studies. The quality of the evidence was assessed using GRADE.

MAIN RESULTS

Six studies (reported in 36 unique publications) were included with a total of 784 participants. Duration of treatment in the included studies ranged from 12 days to six months, with open-label treatment for an additional six months in two of the studies. Five studies compared mannitol with control (a very low dose of mannitol or non-respirable mannitol) and the final study compared mannitol to dornase alfa alone and to mannitol plus dornase alfa. Two large studies had a similar parallel design and provided data for 600 participants, which could be pooled where data for a particular outcome and time point were available. The remaining studies had much smaller sample sizes (ranging from 22 to 95) and data could not be pooled due to differences in design, interventions and population. Pooled evidence from the two large parallel studies was judged to be of low to moderate quality and from the smaller studies was judged to be of low to very low quality. In all studies, there was an initial test to see if participants tolerated mannitol, with only those who could tolerate the drug being randomised; therefore, the study results are not applicable to the cystic fibrosis population as a whole. While the published papers did not provide all the data required for our analysis, additional unpublished data were provided by the drug's manufacturer and the author of one of the studies. Pooling the large parallel studies comparing mannitol to control, up to and including six months, lung function (forced expiratory volume at one second) measured in both mL and % predicted was significantly improved in the mannitol group compared to the control group (moderate-quality evidence). Beneficial results were observed in these studies in adults and in both concomitant dornase alfa users and non-users in these studies. In the smaller studies, statistically significant improvements in lung function were also observed in the mannitol groups compared to the non-respirable mannitol groups; however, we judged this evidence to be of low to very low quality. For the comparisons of mannitol and control, we found no consistent differences in health-related quality of life in any of the domains except for burden of treatment, which was less for mannitol up to four months in the two pooled studies of a similar design; this difference was not maintained at six months. It should be noted that the tool used to measure health-related quality of life was not designed to assess mucolytics and pooling of the age-appropriate tools (as done in some of the included studies) may not be valid so results were judged to be low to very low quality and should be interpreted with caution. Cough, haemoptysis, bronchospasm, pharyngolaryngeal pain and post-tussive vomiting were the most commonly reported side effects in both treatment groups. Where rates of adverse events could be compared, statistically no significant differences were found between mannitol and control groups; although some of these events may have clinical relevance for people with CF. For the comparisons of mannitol to dornase alfa alone and to mannitol plus dornase alfa, very low-quality evidence from a 12-week cross-over study of 28 participants showed no statistically significant differences in the recorded domains of health-related quality of life or measures of lung function. Cough was the most common side effect in the mannitol alone arm but there was no occurrence of cough in the dornase alfa alone arm and the most commonly reported reason of withdrawal from the mannitol plus dornase alfa arm was pulmonary exacerbations. In terms of secondary outcomes of the review (pulmonary exacerbations, hospitalisations, symptoms, sputum microbiology), evidence provided by the included studies was more limited. For all comparisons, no consistent statistically significant and clinically meaningful differences were observed between mannitol and control treatments (including dornase alfa).

AUTHORS' CONCLUSIONS

There is moderate-quality evidence to show that treatment with mannitol over a six-month period is associated with an improvement in some measures of lung function in people with cystic fibrosis compared to control. There is low to very low-quality evidence suggesting no difference in quality of life for participants taking mannitol compared to control. This review provides very low-quality evidence suggesting no difference in lung function or quality of life comparing mannitol to dornase alfa alone and to mannitol plus dornase alfa. The clinical implications from this review suggest that mannitol could be considered as a treatment in cystic fibrosis; but further research is required in order to establish who may benefit most and whether this benefit is sustained in the longer term. Furthermore, studies comparing its efficacy against other (established) mucolytic therapies need to be undertaken before it can be considered for mainstream practice.

Consideration of dornase alfa for the treatment of severe COVID-19 acute respiratory distress syndrome

We propose a likely contribution to severe COVID-19 morbidity by extracellular DNA in neutrophil extracellular traps (NETs). Dornase alfa degrades extracellular DNA to reduce mucus rigidity and accumulation, and was associated with respiratory improvement in a first patient. Dornase alfa should be considered for clinical trials in treatment of severe COVID-19.

When Is Forgetting Not Forgetting? A Discursive Analysis of Differences in Forgetting Talk Between Adults With Cystic Fibrosis With Different Levels of Adherence to Nebulizer Treatments

Forgetting is often cited as a reason why people struggle to adhere to treatments for chronic conditions. Interventions have tried to improve forgetting behavior using reminders. We used a discursive psychological approach to explore differences in how high and low adherers constructed forgetting their nebulizer treatments for cystic fibrosis. Interviews were conducted with 18 adults from a cystic fibrosis center in the United Kingdom. High adherers constructed forgetting treatments as occasional lapses in automaticity and temporary lapses in memory that they found easy to repair. Low adherers utilized forgetting to normalize more consistent nonadherence to treatments. However, it is important to contextualize forgetting as a discursive resource that helped these participants to negotiate moral discourses around adherence to treatment that reminder interventions cannot address; we therefore recommend a more behavioral, patient-focused, theory-driven approach to intervention development.

Exacerbation-Prone Asthma

Patients who are prone to exacerbations of asthma experience significant costs in terms of missed work and school, acute care visits, and hospitalizations. Exacerbations are largely driven by environmental exposures including pollutants, stress, and viral and bacterial pathogens. These exposures are most likely to induce acute severe "asthma attacks" in high-risk patients. These personal risk factors for exacerbations can vary with the phenotype of asthma and age of the patient. In children, allergic sensitization is a strong risk factor, especially for those children who develop sensitization early in life. Airway inflammation is an important risk factor, and biomarkers are under evaluation for utility in detecting eosinophilic and type 2 inflammation and neutrophilic inflammation as indicators of risk for recurrent exacerbations. Insights into inflammatory mechanisms have led to new approaches to prevent exacerbations using mAb-based biologics that target specific type 2 pathways. Challenges remain in developing an evidence base to support precision interventions with these effective yet expensive therapies, and in determining whether these treatments will be safe and effective in young children. Unfortunately, there has been less progress in developing treatments for acute exacerbations. Hopefully, greater understanding of mechanisms relating airway viruses, bacteria, mucin production, and neutrophilic inflammatory responses will lead to additional treatment options for patients experiencing acute exacerbations.

Correspondence between lung function and symptom measures from the Cystic Fibrosis Respiratory Symptom Diary-Chronic Respiratory Infection Symptom Score (CFRSD-CRISS)

BACKGROUND

Pulmonary exacerbations (PEx) in cystic fibrosis (CF) patients reduce quality of life. Lung function, measured by the percent predicted forced expiratory volume in 1 s (ppFEV1), is widely used to evaluate PEx treatments. We analyzed the correspondence of ppFEV1 with 8 patient-reported symptom-based questions from the Cystic Fibrosis Respiratory Symptom Diary-Chronic Respiratory Infection Symptom Score (CFRSD-CRISS).

METHODS

Data were derived from the observational Standardized Treatment of Pulmonary Exacerbations (STOP) study. CF patients who had CFRSD-CRISS and ppFEV1 measurements on ≥2 timepoints were included: 1) day of initial PEx, 2) 7 days later, and/or 3) end of PEx. We calculated age-stratified Spearman correlation coefficients and 95% confidence intervals (95% CIs) between the change in ppFEV1 and change in CFRSD-CRISS items from index to day 7 and from index to the end of PEx treatment.

RESULTS

Lung function and symptom scores improved by the end of treatment; however, correlations between ppFEV1 and the specific CFRSD-CRISS measures were mostly weak to moderate. An exception was that among patients <18, we observed moderately strong correlations between changes in ppFEV1 and cough severity (r = -0.58 (95% CI: -0.80, -0.21)), mucus quantity (r = -0.51 (-0.77, -0.11)), and wheezing (r = -0.53 (-0.78, -0.14)) from index until end of treatment.

CONCLUSIONS

As novel treatments are developed for PEx, it is important to ensure that improvement is measured meaningfully. The generally weak associations between patient-reported symptoms and ppFEV1 that we found suggest that these measures capture different aspects of the disease and both metrics are important when evaluating new treatments.

Detrimental Effect of Type I IFNs During Acute Lung Infection With Pseudomonas aeruginosa Is Mediated Through the Stimulation of Neutrophil NETosis

Pseudomonas aeruginosa is an opportunistic multidrug-resistant pathogen, able to grow in biofilms. It causes life-threatening complications in diseases characterized by the up-regulation of type I interferon (IFN) signaling, such as cancer or viral infections. Since type I IFNs regulate multiple functions of neutrophils, which constitute the first line of anti-bacterial host defense, in this work we aimed to study how interferon-activated neutrophils influence the course of P. aeruginosa infection of the lung. In lungs of infected IFN-sufficient WT mice, significantly elevated bacteria load was observed, accompanied by the prominent lung tissue damage. At the same time IFN-deficient animals seem to be partly resistant to the infection. Lung neutrophils from such IFN-deficient animals release significantly lower amounts of neutrophil extracellular traps (NETs) and reactive oxygen species (ROS), as compared to WT neutrophils. Of note, such IFN-deficient neutrophils show significantly decreased capacity to stimulate biofilm formation by P. aeruginosa. Reduced biofilm production impairs in turn the survival of bacteria in a lung tissue. In line with that, treatment of neutrophils with recombinant IFN-β enhances their NETosis and stimulates biofilm formation by Pseudomonas after co-incubation with such neutrophils. Possibly, bacteria utilizes neutrophil-derived NETs as a scaffold for released biofilms. In agreement with this, in vivo treatment with ROS-scavengers, NETs disruption or usage of the bacterial strains unable to bind DNA, suppress neutrophil-mediated biofilm formation in the lungs. Together, our findings indicate that the excessive activation of neutrophils by type I IFNs leads to their boosted NETosis that in turn triggers biofilm formation by P. aeruginosa and supports its persistence in the infected lung. Targeting these mechanisms could offer a new therapeutic approach to prevent persistent bacterial infections in patients with diseases associated with the up-regulation of type I IFNs.

Profile of tezacaftor/ivacaftor combination and its potential in the treatment of cystic fibrosis

Cystic fibrosis (CF) is a life-limiting autosomal recessive disease caused by dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel. Management of CF has traditionally relied upon managing complications of CFTR protein dysfunction and this has led to a steady improvement in survival of CF patients. However, the landscape of CF care has changed substantially over the last decade with the discovery of CFTR modulators that aim to increase or potentially restore the function of the disease-causing CFTR protein. This narrative review summarizes the development of CFTR therapies so far with emphasis on tezacaftor/ivacaftor combination therapy. We have also summarized the Phase II results of triple combination therapy which promises an effective CFTR modulator therapy for more than 90% of CF patients.