Interstitial lung involvement in rheumatoid arthritis patients treated with abatacept: a prospective observational study

Clin Exp Rheumatol. 2026 Apr 2. doi: 10.55563/clinexprheumatol/yvkk4n. Online ahead of print.

Abstract

Objectives: The aim of this prospective multicentre observational study was to evaluate the clinical course and the incidence of interstitial lung disease (ILD) on a population affected with rheumatoid arthritis (RA).

Methods: Three hundred and twenty-five consecutive RA patients with an ongoing treatment with abatacept were enrolled in the study and followed for 24 months. At the enrolment, ILD was recorded in 20.6% of cases. Patients with ILD were followed according to the current clinical practice, while in patients without ILD, a careful assessment for respiratory symptoms and velcro crackles, also by mean of digital tools, was performed every six months. In this regard, each patient was evaluated by mean of VECTOR, a software able to identify velcro crackles with a diagnostic accuracy of 83.9% and a sensitivity of 93.2% in RA patients.

Results: During the study, no patients discontinued abatacept for a worsening of lung function, and no difference was recorded in two-year retention rate of abatacept between patients with and without ILD. After 24 months, ILD improved or remained stable in more than 85% of cases, while a worsening of radiologic picture was recorded in 14.9% of cases, mainly with usual interstitial pneumonia. Finally, the incidence rate of new-onset ILD was 0.39/100 patients/year.

Conclusions: In conclusion, the presence of ILD did not affect the retention rate of the drug, suggesting a role for abatacept in the treatment of RA-ILD.