Study to Assess CSL787 in Non-cystic Fibrosis Bronchiectasis (NCFB)

Inclusion Criteria: * Male or female, aged ≥ 18 years at the time of providing written informed consent For Part A (SAD) Only: * Healthy and free of medical conditions that could in the opinion of the investigator affect's the subject's participation in the study or the interpretation of results. For Part B (MAD) Only: * Diagnosis of NCFB made by a respiratory physician, confirmed per CT showing bronchial wall dilatation with or without bronchial wall thickening, with a FEV1 ≥ 40% of the predicted value regarding age, height, gender, ethnicity, and FEV1 ≥ 1 L (pre-bronchodilator values) at the Screening Visit. * No antibiotic use within 1 month before the Screening Visit. * Presence of one or more of the following bacteria (H. influenzae, P. aeruginosa, M. catarrhalis, S. pneumoniae, members of Enterobacterales family or S. aureus) in the sputum culture at the Screening Visit. * Has been fully vaccinated against COVID-19 (as per country recommendations) at least 7 days prior to Day 1 Exclusion Criteria: * Evidence of a clinically significant medical condition, disorder, or disease, including but not limited to any of the following: hepatic (hepatitis, cirrhosis); biliary; renal; cardiac; bronchopulmonary; vascular; hematologic; gastrointestinal; allergy; endocrine / metabolic (diabetes, thyroid disorders, adrenal disease); neurologic; psychiatric; immunodeficiency; cancer. * History of chronic respiratory disease (eg, COPD or bronchiectasis) or current asthma with regular treatment including occasional use of an inhaler for exercise induced asthma. * Current moderate-severe allergic disease (eg, allergic rhinitis) with regular treatment. * Diagnosis of cystic fibrosis, mycobacterial disease, connective tissue disease, or alpha-1 antitrypsin deficiency as underlying disease for bronchiectasis. * Oral/parenteral corticosteroid 28 days before the Screening Visit until EOS Visit. Use of long acting bronchodilators (long acting muscarinic antagonists (LAMA) and / or long acting beta2 agonists (LABA) and/or inhaled corticosteroids that have been at a stable dose for at least 3 months before the Screening Visit is permitted; inhalation with hypertonic saline solution is permitted up to and including Day -1. * Any systemic or inhaled antibiotic for acute pulmonary exacerbation within 1 month before the Screening Visit until EOS Visit.