This randomized controlled trial evaluates the therapeutic role of azithromycin in acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF). Baseline severity classification and stratification were performed using the SCALE-IPF framework (Severity Classification and Lung Evaluation for Prognosis in IPF; locked April 2023) to ensure balanced disease severity across randomized arms. End-of-study analyses included descriptive and stratified phenotyping using the IPIM (Idiopathic Pulmonary Fibrosis Phenotypes Identification Model; locked April 2023). Both frameworks were developed within the Assiut University IPF Research Program (2022-2026), a coordinated institutional effort investigating clinical, prognostic, and therapeutic dimensions of IPF. Neither framework altered randomization procedures, treatment allocation, or study endpoints; they were applied to improve standardization, reproducibility, and interpretability of results.