Bronchiectasis is a chronic respiratory disease characterized by recurrent infections, inflammation, and progressive lung damage. Frequent exacerbations are associated with increased morbidity, accelerated lung function decline, and reduced quality of life. Preventing exacerbations is a key therapeutic goal. Moxifloxacin, a fluoroquinolone antibiotic with broad-spectrum activity, may play a role in intermittent eradication therapy to reduce bacterial load, achieve microbiological clearance, and minimize exacerbation frequency.

This randomized controlled trial will evaluate the effectiveness and safety of long-term intermittent moxifloxacin therapy compared with standard care in patients with non-cystic fibrosis bronchiectasis.

Inclusion Criteria:

• Adults ≥18 years of age.
• Confirmed diagnosis of non-cystic fibrosis bronchiectasis by high-resolution CT (HRCT).
• History of ≥2 bronchiectasis exacerbations in the previous 12 months.

Exclusion Criteria:

• Diagnosis of cystic fibrosis-related bronchiectasis.
• Known hypersensitivity or contraindication to fluoroquinolones (including moxifloxacin).
• Severe hepatic impairment or severe renal impairment (eGFR <30 mL/min/1.73 m²).
• Pregnancy or breastfeeding.
• History of significant QT prolongation, arrhythmia, or concurrent use of QT-prolonging drugs.
• Use of long-term suppressive antibiotics for bronchiectasis in the past 3 months.