500 patients to test if daily azithromycin keeps bronchiectasis attacks at bay

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Adult patients aged 18 years or older. * Clinically and radiologically confirmed non-cystic fibrosis bronchiectasis (NCFB). * Diagnosis supported by clinical assessment and high-resolution computed tomography (HRCT). * Patients attending outpatient clinics, inpatient wards, respiratory follow-up services, or routine bronchiectasis care pathways at Assiut University Hospitals during the enrollment period. * Suitable for baseline disease-signature assessment. * Able to undergo protocol-defined clinical, functional, radiological, oxygenation, inflammatory, symptom, and safety assessment. * Able to complete planned 12-month follow-up. * Eligible for randomization after baseline safety evaluation. * Written informed consent obtained from the participant or legal representative. Exclusion Criteria: * Cystic fibrosis-related bronchiectasis. * Traction bronchiectasis due to advanced fibrotic interstitial lung disease as the dominant respiratory diagnosis. * Active pulmonary tuberculosis at enrollment. * Active nontuberculous mycobacterial pulmonary disease requiring specific treatment at enrollment. * Active malignancy or terminal non-respiratory illness expected to prevent planned follow-up. * Acute life-threatening illness preventing safe enrollment, baseline assessment, or randomization. * Recent major thoracic surgery or acute thoracic trauma interfering with baseline respiratory assessment. * Known hypersensitivity, contraindication, or serious intolerance to azithromycin or macrolide therapy. * Baseline cardiac findings judged by the investigator to make long-term azithromycin unsafe. * Requirement for long-term maintenance macrolide therapy at enrollment. * Current long-term maintenance macrolide use that cannot be safely discontinued before enrollment. * Inability to complete required baseline disease-signature assessment. * Inability or unwillingness to complete planned 12-month follow-up. * Refusal to participate.