Development and initial validation of the bronchiectasis exacerbation and symptom tool (BEST)

Phase 3 Trial of the DPP-1 Inhibitor Brensocatib in Bronchiectasis

BACKGROUND

In bronchiectasis, neutrophilic inflammation is associated with an increased risk of exacerbations and disease progression. Brensocatib, an oral, reversible inhibitor of dipeptidyl peptidase 1 (DPP-1), targets neutrophil serine proteases, key mediators of neutrophilic inflammation.

METHODS

In a phase 3, double-blind trial, we randomly assigned patients with bronchiectasis (in a 1:1:1 ratio for adults and a 2:2:1 ratio for adolescents) to receive brensocatib (10 mg or 25 mg once per day) or placebo. The primary end point was the annualized rate of adjudicated pulmonary exacerbations over a 52-week period. The secondary end points, listed in hierarchical testing order, were the time to the first exacerbation during the 52-week period; the percentage of patients remaining exacerbation-free at week 52; the change in forced expiratory volume in 1 second (FEV1); the annualized rate of severe exacerbations; and change in quality of life.

RESULTS

A total of 1721 patients (1680 adults and 41 adolescents) underwent randomization and received brensocatib or placebo. The annualized rate of pulmonary exacerbations was 1.02 in the 10-mg brensocatib group, 1.04 in the 25-mg brensocatib group, and 1.29 in the placebo group (rate ratio, brensocatib vs. placebo, 0.79 [95% confidence interval {CI}, 0.68 to 0.92; adjusted P = 0.004] with the 10-mg dose and 0.81 [95% CI, 0.69 to 0.94; adjusted P = 0.005] with the 25-mg dose). The hazard ratio for the time to the first exacerbation was 0.81 (95% CI, 0.70 to 0.95; adjusted P = 0.02) with the 10-mg dose and 0.83 (95% CI, 0.70 to 0.97; adjusted P = 0.04) with the 25-mg dose. In each brensocatib group, 48.5% of patients remained exacerbation-free at week 52, as compared with 40.3% in the placebo group (rate ratio, 1.20 [95% CI, 1.06 to 1.37; adjusted P = 0.02] with the 10-mg dose and 1.18 [95% CI, 1.04 to 1.34; adjusted P = 0.04] with the 25-mg dose). At week 52, FEV1 had declined by 50 ml with the 10-mg dose, 24 ml with the 25-mg dose, and 62 ml with placebo (least-squares mean difference vs. placebo, 11 ml [95% CI, -14 to 37; adjusted P = 0.38] with the 10-mg dose and 38 ml [95% CI, 11 to 65; adjusted P = 0.04] with the 25-mg dose). The incidence of adverse events was similar across groups, except for a higher incidence of hyperkeratosis with brensocatib.

CONCLUSIONS

Among patients with bronchiectasis, once-daily treatment with brensocatib (10 mg or 25 mg) led to a lower annualized rate of pulmonary exacerbations than placebo, and the decline in FEV1 was less with the 25-mg dose of brensocatib than with placebo. (Funded by Insmed; ASPEN ClinicalTrials.gov number, NCT04594369; EudraCT number, 2020-003688-25.).

Patient-managed interventions for adults with bronchiectasis: evidence, challenges and prospects

Bronchiectasis is a chronic lung condition which is characterised by recurrent chest infections, chronic sputum production and cough, and limited exercise tolerance. While bronchiectasis may be caused by various aetiologies, these features are shared by most patients with bronchiectasis regardless of the cause. This review consolidates the existing evidence on patient-managed interventions for adults with bronchiectasis, while also outlining areas for future research. Airway clearance techniques and hyperosmolar agents are key components of the bronchiectasis management and consistently recommended for clinical implementation. Questions around their prescription, such as optimal sequence of delivery, are still to be answered. Pulmonary rehabilitation and exercise are also recommended for patients with bronchiectasis. Relatively strong evidence underpins this recommendation during a clinically stable stage of the disease, although the role of pulmonary rehabilitation following an exacerbation is still unclear. Additionally, self-management programmes feature prominently in bronchiectasis treatment, yet the lack of consensus regarding their definition and outcomes presents hurdles to establishing a cohesive evidence base. Moreover, cough, a cardinal symptom of bronchiectasis, warrants closer examination. Although managing cough in bronchiectasis may initially appear risky, further research is necessary to ascertain whether strategies employed in other respiratory conditions can be safely and effectively adapted to bronchiectasis, particularly through identifying patient responder populations and criteria where cough may not enhance airway clearance efficacy and its control is needed. Overall, there is a growing recognition of the importance of patient-managed interventions in the bronchiectasis management. Efforts to improve research methodologies and increase research funding are needed to further advance our understanding of these interventions, and their role in optimising patient care and outcomes.

Exacerbations of bronchiectasis

Bronchiectasis presents a significant challenge due to its rising prevalence, associated economic burden and clinical heterogeneity. This review synthesises contemporary understanding and literature of bronchiectasis exacerbations, addressing the transition from stable state to exacerbations, underlining the importance of early and precise recognition, rigorous severity assessment, prompt treatment, and prevention measures, as well as emphasising the need for strategies to assess and improve early and long-term patient outcomes. The review highlights the interplay between stable state phases and exacerbations in bronchiectasis, introducing the concept of "exogenous and endogenous changes in airways homeostasis" and the "adapted island model" with a particular focus on "frequent exacerbators", a group of patients associated with specific clinical characteristics and worse outcomes. The pathophysiology of exacerbations is explored through the lens of microbial and nonmicrobial triggers and the presence and the activity of comorbidities, elaborating on the impact of both exogenous insults, such as infections and pollution, and endogenous factors such as inflammatory endotypes. Finally, the review proposes a multidisciplinary approach to care, integrating advancements in precision medicine and biomarker research, paving the way for tailored treatments that challenge the traditional antibiotic paradigm.

A systematic literature review of the clinical and socioeconomic burden of bronchiectasis

BACKGROUND

The overall burden of bronchiectasis on patients and healthcare systems has not been comprehensively described. Here, we present the findings of a systematic literature review that assessed the clinical and socioeconomic burden of bronchiectasis with subanalyses by aetiology (PROSPERO registration: CRD42023404162).

METHODS

Embase, MEDLINE and the Cochrane Library were searched for publications relating to bronchiectasis disease burden (December 2017-December 2022). Journal articles and congress abstracts reporting on observational studies, randomised controlled trials and registry studies were included. Editorials, narrative reviews and systematic literature reviews were included to identify primary studies. PRISMA guidelines were followed.

RESULTS

1585 unique publications were identified, of which 587 full texts were screened and 149 were included. A further 189 citations were included from reference lists of editorials and reviews, resulting in 338 total publications. Commonly reported symptoms and complications included dyspnoea, cough, wheezing, sputum production, haemoptysis and exacerbations. Disease severity across several indices and increased mortality compared with the general population was reported. Bronchiectasis impacted quality of life across several patient-reported outcomes, with patients experiencing fatigue, anxiety and depression. Healthcare resource utilisation was considerable and substantial medical costs related to hospitalisations, treatments and emergency department and outpatient visits were accrued. Indirect costs included sick pay and lost income.

CONCLUSIONS

Bronchiectasis causes significant clinical and socioeconomic burden. Disease-modifying therapies that reduce symptoms, improve quality of life and reduce both healthcare resource utilisation and overall costs are needed. Further systematic analyses of specific aetiologies and paediatric disease may provide more insight into unmet therapeutic needs.

Brensocatib in non-cystic fibrosis bronchiectasis: ASPEN protocol and baseline characteristics

Introduction

Brensocatib is an investigational, oral, reversible inhibitor of dipeptidyl peptidase-1 shown to prolong time to first exacerbation in adults with bronchiectasis. Outlined here are the clinical trial design, and baseline characteristics and treatment patterns of adult patients enrolled in the phase 3 ASPEN trial (NCT04594369).

Methods

The ASPEN trial is a global study enrolling patients with a clinical history consistent with bronchiectasis (cough, chronic sputum production and/or recurrent respiratory infections), diagnosis confirmed radiologically and ≥2 exacerbations in the prior 12 months. It was designed to evaluate the impact of two brensocatib doses (10 mg and 25 mg) on exacerbation rate over a 52-week treatment period versus placebo. Comprehensive clinical data, including demographics, disease severity, lung function, Pseudomonas aeruginosa status and quality of life, were collected at baseline.

Results

1682 adults from 35 countries were randomised from December 2020 to March 2023. Mean age was 61.3 years and 64.7% were female. ∼70% had moderate-to-severe Bronchiectasis Severity Index (BSI) scores, 29.3% had ≥3 exacerbations in the prior 12 months and 35.7% were positive for P. aeruginosa. Mean BSI scores were highest in Australia/New Zealand (8.3) and lowest in Latin America (5.9). Overall, the most common aetiology was idiopathic (58.4%). In P. aeruginosa-positive versus P. aeruginosa-negative patients, lung function was lower, with greater long-term macrolide (21.5% versus 14.0%) and inhaled corticosteroid use (63.5% versus 53.9%). There was wide regional variation in long-term antibiotic use in patients with bronchiectasis and P. aeruginosa.

Discussion

ASPEN baseline characteristics and treatment profiles were representative of a global bronchiectasis population.

Bronchiectasis management in adults: state of the art and future directions

Formerly regarded as a rare disease, bronchiectasis is increasingly recognised. A renewed interest in this disease has led to significant progress in bronchiectasis research. Randomised clinical trials (RCTs) have demonstrated the benefits of airway clearance techniques, inhaled antibiotics and long-term macrolide therapy in bronchiectasis patients. However, the heterogeneity of bronchiectasis remains one of the most challenging aspects of management. Phenotypes and endotypes of bronchiectasis have been identified to help find "treatable traits" and partially overcome disease complexity. The goals of therapy for bronchiectasis are to reduce the symptom burden, improve quality of life, reduce exacerbations and prevent disease progression. We review the pharmacological and non-pharmacological treatments that can improve mucociliary clearance, reduce airway inflammation and tackle airway infection, the key pathophysiological features of bronchiectasis. There are also promising treatments in development for the management of bronchiectasis, including novel anti-inflammatory therapies. This review provides a critical update on the management of bronchiectasis focusing on treatable traits and recent RCTs.

Airway clearance management in people with bronchiectasis: data from the European Bronchiectasis Registry (EMBARC)

BACKGROUND

International guidelines recommend airway clearance management as one of the important pillars of bronchiectasis treatment. However, the extent to which airway clearance is used for people with bronchiectasis in Europe is unclear. The aim of the study was to identify the use of airway clearance management in patients with bronchiectasis across different countries and factors influencing airway clearance use.

METHODS

This was a prospective observational study using data from the European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) Registry between January 2015 and April 2022. Prespecified options for airway clearance management were recorded, including airway clearance techniques, devices and use of mucoactive drugs.

RESULTS

16 723 people with bronchiectasis from 28 countries were included in the study. The mean age was 67 years (interquartile range 57-74 years, range 18-100 years) and 61% were female. 72% of the participants reported daily sputum expectoration and 52% (95% CI 51-53%) of all participants reported using regular airway clearance management. Active cycle of breathing technique was used by 28% of the participants and airway clearance devices by 16% of participants. The frequency of airway clearance management and techniques used varied significantly between different countries. Participants who used airway clearance management had greater disease severity and worse symptoms, including a higher daily sputum volume, compared to those who did not use it regularly. Mucoactive drugs were also more likely to be used in participants with more severe disease. Access to specialist respiratory physiotherapy was low throughout Europe, but particularly low in Eastern Europe.

CONCLUSIONS

Only a half of people with bronchiectasis in Europe use airway clearance management. Use of and access to devices, mucoactive drugs and specialist chest physiotherapy appears to be limited in many European countries.

Quality-of-Life Bronchiectasis Respiratory Symptom Scale Predicts the Risk of Exacerbations in Adults with Bronchiectasis: A Prospective Observational Study

Rationale: The relationship between symptoms, measured using a validated disease-specific questionnaire, and longitudinal exacerbation risk has not been demonstrated in bronchiectasis. Objectives: The aim of this study is to investigate whether baseline symptoms, assessed using the Quality-of-Life Bronchiectasis Respiratory Symptom Scale (QoL-B-RSS) and its individual component scores, could predict future exacerbation risk in patients with bronchiectasis. Methods: The study included 436 adults with bronchiectasis from three tertiary hospitals. Symptoms were measured using the QoL-B-RSS, with scores ranging from 0 to 100, where lower scores indicated more severe symptoms. We examined whether symptoms as continuous measures were associated with the risk of exacerbation over 12 months. The analysis was also repeated for individual components of the QoL-B-RSS score. Results: The baseline QoL-B-RSS score was associated with an increased risk of exacerbations (rate ratio, 1.25 for each 10-point decrease; 95% confidence interval [CI], 1.15-1.35; P < 0.001), hospitalizations (rate ratio, 1.24; 95% CI, 1.05-1.43; P = 0.02), and reduced time to the first exacerbation (hazard ratio, 1.12; 95% CI, 1.03-1.21; P = 0.01) over 12 months, even after adjusting for relevant confounders, including exacerbation history. The QoL-B-RSS score was comparable to exacerbation history in its association with future frequent exacerbations (defined as three or more exacerbations per year) and hospitalization (area under the curve, 0.86 vs. 0.84; P = 0.46; and area under the curve, 0.81 vs. 0.83; P = 0.41, respectively). Moreover, patients with more severe symptoms in the majority of individual components of the QoL-B-RSS were more likely to experience exacerbations. Conclusions: Symptoms can serve as useful indicators for identifying patients at increased risk of exacerbation in bronchiectasis. Beyond relying solely on exacerbation history, a comprehensive assessment of symptoms could facilitate timely and cost-effective implementation of interventions for exacerbation prevention.

A phase 4 multicentre, 2×2 factorial randomised, double-blind, placebo-controlled trial to investigate the efficacy and safety of tobramycin inhalation solution for Pseudomonas aeruginosa eradication in bronchiectasis: ERASE

Chronic Pseudomonas aeruginosa (PA) infection significantly contributes to morbidity and mortality in bronchiectasis patients. Initiating antibiotics early may lead to the eradication of PA. Here we outline the design of a trial (ERASE; NCT06093191) assessing the efficacy and safety of inhaled tobramycin, alone or with oral ciprofloxacin, in bronchiectasis patients with a new isolation of PA. This multicentre, 2×2 factorial randomised, double-blind, placebo-controlled, parallel-group trial includes a 2-week screening period, a 12-week treatment phase (with a combination of ciprofloxacin or a placebo at initial 2 weeks) and a 24-week follow-up. 364 adults with bronchiectasis and a new PA isolation will be randomly assigned to one of four groups: placebo (inhaled saline and ciprofloxacin placebo twice daily), ciprofloxacin alone (750 mg ciprofloxacin and inhaled saline twice daily), inhaled tobramycin alone (inhaled 300 mg tobramycin and ciprofloxacin placebo twice daily) or a combination of both drugs (inhaled 300 mg tobramycin and 750 mg ciprofloxacin twice daily). The primary objective of this study is to assess the proportion of patients successfully eradicating PA in each group by the end of the study. Efficacy will be evaluated based on the eradication rate of PA at other time points (12, 24 and 36 weeks), the occurrence of exacerbations and hospitalisations, time to first pulmonary exacerbations, patient-reported outcomes, symptom measures, pulmonary function tests and the cost of hospitalisations. To date no randomised trial has evaluated the benefit of different PA eradication strategies in bronchiectasis patients. The ERASE trial will therefore generate crucial data to inform future clinical guidelines.

Sputum pathogen spectrum and clinical outcomes of upper respiratory tract infection in bronchiectasis exacerbation: a prospective cohort study

Upper respiratory tract infection (URTI) is common in humans. We sought to profile sputum pathogen spectrum and impact of URTI on acute exacerbation of bronchiectasis (AE). Between March 2017 and December 2021, we prospectively collected sputum from adults with bronchiectasis. We stratified AEs into events related (URTI-AE) and unrelated to URTI (non-URTI-AE). We captured URTI without onset of AE (URTI-non-AE). We did bacterial culture and viral detection with polymerase chain reaction, and explored the pathogen spectrum and clinical impacts of URTI-AE via longitudinal follow-up. Finally, we collected 479 non-AE samples (113 collected at URTI-non-AE and 225 collected at clinically stable) and 170 AE samples (89 collected at URTI-AE and 81 collect at non-URTI-AE). The viral detection rate was significantly higher in URTI-AE (46.1%) than in non-URTI-AE (4.9%) and URTI-non-AE (11.5%) (both P < 0.01). Rhinovirus [odds ratio (OR): 5.00, 95% confidence interval (95%CI): 1.06-23.56, P = 0.03] detection was independently associated with URTI-AE compared with non-URTI-AE. URTI-AE tended to yield higher viral load and detection rate of rhinovirus, metapneumovirus and bacterial shifting compared with URTI-non-AE. URTI-AE was associated with higher initial viral loads (esp. rhinovirus, metapneumovirus), greater symptom burden (higher scores of three validated questionnaires) and prolonged recovery compared to those without. Having experienced URTI-AE predicted a greater risk of future URTI-AE (OR: 10.90, 95%CI: 3.60-33.05). In summary, URTI is associated with a distinct pathogen spectrum and aggravates bronchiectasis exacerbation, providing the scientific rationale for the prevention of URTI to hinder bronchiectasis progression.

The BED-Pro Tool: facilitating the detection of bronchiectasis exacerbations

The Bronchiectasis Exacerbation Diary is an eight-item patient-reported outcome instrument for detecting exacerbations in bronchiectasis https://bit.ly/3k2IH4p.

The Bronchiectasis Exacerbation Diary: a novel patient-reported outcome for non-cystic fibrosis bronchiectasis

Bronchiectasis is a chronic, progressive lung disease believed to result from a vicious cycle of infection and inflammation, with symptoms of chronic cough with sputum production, chronic fatigue, rhinosinusitis, chest pain, breathlessness and haemoptysis. There are currently no established instruments to monitor daily symptoms and exacerbations for use in clinical trials. Following a literature review and three expert clinician interviews, we conducted concept elicitation interviews with 20 patients with bronchiectasis to understand their personal disease experience. Findings from literature and clinician feedback were used to develop a draft version of the Bronchiectasis Exacerbation Diary (BED), which was designed to monitor key symptoms on a daily basis and during exacerbations. Patients were eligible to be interviewed if they were US residents aged ≥18 years, had a computed tomography scan-confirmed diagnosis of bronchiectasis with ≥two exacerbations in the previous 2 years and had no other uncontrolled respiratory conditions. Four waves of five patient interviews each were conducted. Patients (n=20) had a mean±_SD age of 53.9±12.8 years, and most were female (85%) and white (85%). A total of 33 symptoms and 23 impacts arose from the patient concept elicitation interviews. The BED was revised and finalised based upon patient feedback. The final BED is a novel, eight-item patient-reported outcome (PRO) instrument for monitoring key exacerbation symptoms on a daily basis with content validity established through comprehensive qualitative research and direct patient insight. The BED PRO development framework will be completed following psychometric evaluations of the data from a phase 3 bronchiectasis clinical trial.

Active cycle of breathing technique versus oscillating PEP therapy versus walking with huffing during an acute exacerbation of bronchiectasis: a randomised, controlled trial protocol

BACKGROUND

Airway clearance techniques (ACTs) for individuals with bronchiectasis are routinely prescribed in clinical practice and recommended by international guidelines, especially during an acute exacerbation. However, there is limited evidence of the efficacy of these techniques during an exacerbation to improve sputum expectoration, health-related quality-of-life (HRQOL) or exercise tolerance. The primary aim of this study is to compare the effects of the active cycle of breathing technique (ACBT), oscillating positive expiratory pressure (O-PEP) therapy, and walking with huffing on sputum expectoration for adults hospitalised with an acute exacerbation of bronchiectasis. Secondary aims are to compare the effects of these interventions on HRQOL, health status, exacerbation rates and hospital admissions in a six-month period following hospital discharge.

METHODS

This multi-centre randomised controlled trial will recruit adults with an acute exacerbation of bronchiectasis requiring hospital admission. Participants will be randomised to receive one of three interventions: ACBT, O-PEP therapy, and walking with huffing. Outcome measures including sputum volume during and 1-h post ACT session, and 24-h sputum, as well as health status, HRQOL and exercise capacity will be completed during inpatient stay on day 2 and day 6 of admission, and within 24 h of hospital discharge. Time to first exacerbation, and time to first hospitalisation will be monitored via monthly phone calls for six months post hospital discharge. Health status and HRQOL will be assessed after discharge at two and six months, and exercise capacity will be assessed at six months post hospital discharge.

DISCUSSION

Despite recommendations regarding the importance of ACT for individuals with bronchiectasis during an acute exacerbation, there is a gap in the literature regarding effectiveness of ACT when undertaken by individuals in this clinical state. This study will add to the evidence base regarding the effectiveness of commonly implemented ACTs during a hospital admission with an exacerbation of bronchiectasis. Additionally, it will contribute to knowledge of the long term effects on important and patient-centred outcomes, including incidence of future exacerbations, and HRQOL, which has not been previously established. Trial registration Registered on the Australian and New Zealand Clinical Trials Registry (ACTRN12621000428864).

Bronchiectasis exacerbation: a narrative review of causes, risk factors, management and prevention

Background and Objective

Bronchiectasis exacerbations are significant events in the natural course of the disease and determine long-term clinical outcomes. This review aims to discuss the definition, causes, risk factors, management and prevention of bronchiectasis exacerbations.

Methods

The PubMed database was searched for relevant articles published in English between January 1990 and March 2022 using keywords "bronchiectasis" and "exacerbation".

Key Content and Findings

Causes of bronchiectasis exacerbation are multifactorial; it can be associated with bacterial and viral pathogens, host inflammatory responses, and external environmental effects. In addition, recent advances in bronchiectasis research highlight the phenotype of patients who are more prone to exacerbations, including those with chronic Pseudomonas aeruginosa infection, worse symptoms, greater lung inflammation and comorbid airway diseases. Once bronchiectasis exacerbations occur, antibiotics are the mainstay treatment. Preventing exacerbations is of paramount importance because frequent exacerbations are linked to a detrimental disease course and higher mortality. To prevent frequent exacerbations, clinicians should attempt to understand the risk factors for exacerbation that are amenable to therapeutic intervention: so called "treatable traits". Treatments are personalised but include improving mucociliary clearance by physiotherapy and mucoactive therapy, reducing airway infection by inhaled antibiotics, and inflammation by long-term macrolide or in specific subpopulations, inhaled corticosteroids (ICS). Novel approaches to prevent exacerbations including direct anti-inflammatory therapies are in development for bronchiectasis.

Conclusions

Future research is needed to better manage and prevent exacerbations in patients with bronchiectasis, although recent studies have characterised frequent exacerbator phenotype and enhanced our understanding of various aspects of exacerbations.

Monitoring daily symptoms and (self-reported) exacerbations in patients with bronchiectasis: a prospective study

Background

Exacerbations are pivotal events in the natural history of patients with non-cystic fibrosis bronchiectasis (NCFB), since they have a negative impact on the functional evolution of these individuals. The daily symptoms of patients with NCFB show great variability, which negatively affects their self-perception of symptoms and exacerbations. The aim of this study was to identify daily symptoms in patients with NCFB, and to investigate whether there is a correlation between the frequency of self-reported exacerbations and events defined according to the criteria established in the literature to define exacerbation in bronchiectasis.

Methods

This observational and prospective study was carried out in outpatient clinics of a Brazilian public university hospital. Over 24 weeks, patients completed a diary in which daily symptoms, self-reported exacerbations, and demands for medical care for respiratory symptoms were recorded. The instrument used (diary and symptom scores ranging from 0 to 12) were developed by the researchers. The participants also answered questionnaires mMRC, Leicester's, and St. George's Respiratory (SGRQ).

Results

Twenty-eight patients returned the diary, their mean age was 54 years, and 50% out of them were classified as mild by the FACED score. Cough (64%) and expectoration (62%) were the most frequent symptoms. Correlations were found between the stability score and the mMRC (r=0.4727, p=0.011) and SGRQ (r=0.6748, p<0.0001) questionnaires. The number of self-perceived exacerbations (24) was significantly lower than exacerbations using the exacerbation consensus (63) (p<0.01). Additionally, no correlation was found between these two criteria.

Conclusions

There was great variability of symptoms among the individuals sampled, and even for the same individual, over time. Patients had low self-perception of exacerbations, which suggests that strategies aimed at improving this self-perception may contribute to the early detection of exacerbations.

Pseudomonas aeruginosa in bronchiectasis: infection, inflammation, and therapies

Introduction: Bronchiectasis is a chronic endobronchial suppurative disease characterized by irreversibly dilated bronchi damaged by repeated polymicrobial infections and predominantly, neutrophilic airway inflammation. Some consider bronchiectasis a syndromic consequence of several different causes whilst others view it as an individual disease entity. In most patients, identifying an underlying cause remains challenging. The acquisition and colonization of affected airways by Pseudomonas aeruginosa represent a critical and adverse clinical consequence for its progression and management.Areas covered: In this review, we outline clinical and pre-clinical peer-reviewed research published in the last 5 years, focusing on the pathogenesis of bronchiectasis and the role of P. aeruginosa and its virulence in shaping host inflammatory and immune responses in the airway. We further detail its role in airway infection, the lung microbiome, and address therapeutic options in bronchiectasis.Expert opinion: P. aeruginosa represents a key pulmonary pathogen in bronchiectasis that causes acute and/or chronic airway infection. Eradication can prevent adverse clinical consequence and/or disease progression. Novel therapeutic strategies are emerging and include combination-based approaches. Addressing airway infection caused by P. aeruginosa in bronchiectasis is necessary to prevent airway damage, loss of lung function and exacerbations, all of which contribute to adverse clinical outcome.