METHODS: Between 2015 and 2018, we evaluated 131 out of 180 (72.8%) children of adolescents from the original studies at a single follow-up visit. We administered standardized questionnaires, reviewed medical records, undertook clinical examinations, performed spirometry, and scored available chest computed tomography scans.

RESULTS: Participants were seen at a mean age of 12.3 years (standard deviation: 2.6) and a median of 9.0 years (range: 5.0-13.0) after their original recruitment. With increasing age, rates of acute lower respiratory infections (ALRI) declined, while lung function was mostly within population norms (median forced expiry volume in one-second = 90% predicted, interquartile range [IQR]: 81-105; forced vital capacity [FVC] = 98% predicted, IQR: 85-114). However, 43 out of 111 (38.7%) reported chronic cough episodes. Their overall global rating judged by symptoms, including ALRI frequency, examination findings, and spirometry was well (20.3%), stable (43.9%), or improved (35.8%). Multivariable regression identified household tobacco exposure and age at first ALRI-episode as independent risk factors associated with lower FVC% predicted values.

METHODS AND ANALYSIS: This multicentre, parallel, double-blind, placebo-controlled randomised trial involving seven hospitals in six cities from three different countries commenced in May 2016. Three-hundred-and-fourteen eligible Australian Indigenous, New Zealand Māori/Pacific and Malaysian children (aged 0.25 to 5 years) hospitalised for community-acquired, chest X-ray (CXR)-proven pneumonia are being recruited. Following intravenous antibiotics and 3 days of amoxicillin-clavulanate, they are randomised (stratified by site and age group, allocation-concealed) to receive either: (i) amoxicillin-clavulanate (80 mg/kg/day (maximum 980 mg of amoxicillin) in two-divided doses or (ii) placebo (equal volume and dosing frequency) for 8 days. Clinical data, nasopharyngeal swab, bloods and CXR are collected. The primary outcome is the proportion of children without chronic respiratory symptom/signs of bronchiectasis at 24 months. The main secondary outcomes are 'clinical cure' at 4 weeks, time-to-next respiratory-related hospitalisation and antibiotic resistance of nasopharyngeal respiratory bacteria.

ETHICS AND DISSEMINATION: The Human Research Ethics Committees of all the recruiting institutions (Darwin: Northern Territory Department of Health and Menzies School of Health Research; Auckland: Starship Children's and KidsFirst Hospitals; East Malaysia: Likas Hospital and Sarawak General Hospital; Kuala Lumpur: University of Malaya Research Ethics Committee; and Klang: Malaysian Department of Health) have approved the research protocol version 7 (13 August 2018). The RCT and other results will be submitted for publication.

METHODS AND ANALYSIS: We are undertaking an international multicentre, double-blind, placebo-RCT to evaluate whether 12 months of erdosteine is beneficial for children and adults with bronchiectasis. We will recruit 194 children and adults with bronchiectasis to a parallel, superiority RCT at eight sites across Australia, Malaysia and Philippines. Our primary endpoint is the rate of exacerbations over 12 months. Our main secondary outcomes are QoL, exacerbation duration, time-to-next exacerbation, hospitalisations and lung function.

ETHICS AND DISSEMINATION: The Human Research Ethics Committees (HREC) of Children's Health Queensland (for all Australian sites), University of Malaya Medical Centre (Malaysia) and St. Luke's Medical Centre (Philippines) approved the study. We will publish the results and share the outcomes with the academic and medical community, funding and relevant patient organisations.

METHODS: We undertook a multicenter, double-blind, superiority, randomized controlled trial involving 7 Australian, New Zealand, and Malaysian hospitals. Children aged 3 months to ≤5 years hospitalized with radiographic-confirmed CAP who received 1-3 days of intravenous antibiotics, then 3 days of oral amoxicillin-clavulanate, were randomized to either extended-course (8-day oral amoxicillin-clavulanate) or standard-course (8-day oral placebo) arms. Children were reviewed at 12 and 24 months. The primary outcome was children with the composite endpoint of chronic respiratory symptoms/signs (chronic cough at 12 and 24 months; ≥1 subsequent hospitalized acute lower respiratory infection by 24 months; or persistent and/or new chest radiographic signs at 12-months) at 24-months postdischarge, analyzed by intention-to-treat, where children with incomplete follow-up were assumed to have chronic respiratory symptoms/signs ("worst-case" scenario).

RESULTS: A total of 324 children were randomized [extended-course (n = 163), standard-course (n = 161)]. For our primary outcome, chronic respiratory symptoms/signs occurred in 97/163 (60%) and 94/161 (58%) children in the extended-courses and standard-courses, respectively [relative risk (RR) = 1.02, 95% confidence interval (CI): 0.85-1.22]. Among children where all sub-composite outcomes were known, chronic respiratory symptoms/signs between groups, RR = 1.10, 95% CI: 0.69-1.76 [extended-course = 27/93 (29%) and standard-course = 24/91 (26%)]. Additional sensitivity analyses also revealed no between-group differences.