A Phase IIa, Randomized, Double-Blind, Placebo-Controlled Trial of JKN2403 in COPD

Inclusion Criteria: * Written informed consent; able and willing to comply with study procedures. * Adults with documented COPD diagnosis and medical history consistent with guideline criteria. * Relevant exposure history consistent with COPD (e.g., smoking). * On stable, guideline-based maintenance COPD therapy prior to randomization, per investigator judgment. * Protocol-defined exacerbation history, symptom burden, and lung function at screening. Exclusion Criteria: * Current or past asthma, or other clinically significant respiratory disease that may confound assessment. * Clinically significant uncontrolled comorbidities that increase risk or interfere with participation/outcomes. * Immunodeficiency/immune dysregulation, active autoimmune disease requiring systemic immunosuppression, or significant opportunistic infection history. * Active clinically significant infection or recent infection requiring systemic therapy; recent protocol-defined COPD exacerbation. * Current/recent malignancy (except low-risk, adequately treated cancers per protocol) or clinically significant abnormal screening labs. * Prohibited recent vaccines or therapies, prior relevant biologic/targeted therapy exposure, severe hypersensitivity to biologics/IMP, - pregnancy/breastfeeding, or inability to comply (including substance abuse), per investigator judgment.