Real-World Data on Halting Radiographic Progression with Antifibrotics in Connective Tissue Disease-Associated...

Background/Objectives: Connective tissue disease-associated interstitial lung disease (CTD-ILD) is linked to substantial morbidity and mortality. While nintedanib (NTB) slows lung function decline in progressive pulmonary fibrosis (PPF), real-world data-particularly regarding radiographic outcomes-remain limited. We aimed to evaluate the real-world effectiveness and tolerability of antifibrotic therapy-predominantly NTB-on radiographic and functional outcomes in a Hungarian CTD-ILD cohort. Methods: We conducted a retrospective observational cohort study including 72 patients with progressive CTD-ILD who initiated antifibrotic therapy at two Hungarian tertiary centers between January 2021 and June 2025. The primary endpoint was the proportion of patients without significant radiographic progression at 6-12 months, based on blinded assessment of paired high-resolution computed tomography (HRCT) scans by two thoracic radiologists. Secondary endpoints included changes in forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO) at 6 and 12 months, safety and tolerability, and correlations between lung function and disease-related factors. Results: The cohort comprised systemic sclerosis-ILD (n = 25), rheumatoid arthritis-ILD (n = 23), and other CTD-ILD (n = 24). Radiographic stability was observed in 65.8-78.9% of patients, with improvement most commonly seen in ground-glass opacities, while traction bronchiectasis remained largely unchanged. Radiographic disease extent showed the strongest inverse correlation with baseline FVC and DLCO (p < 0.05). Significant improvements in FVC and DLCO were observed at 6 and 12 months (p < 0.001). Antifibrotic therapy was well tolerated, including in combination with immunosuppressive treatment. Conclusions: These real-world data support the effectiveness and safety of NTB in PPF-CTD-ILD and highlight radiologic disease burden as a key determinant of functional impairment.