Tocilizumab therapy in rheumatoid arthritis with interstitial lung disease: a multicentre retrospective study

Background: Interstitial lung disease (ILD) is the most severe extra-articular manifestation of rheumatoid arthritis (RA). Although it is responsible of 10-20% of all RA mortality, no controlled studies are available for the treatment of RA-ILD and its therapeutic approach is still debated. Aims: To analyse the evolution of ILD in a population of RA patients treated with tocilizumab (TCZ). Methods: In this national multicentre study, we retrospectively collected patients with RA-ILD treated with at least one dose of TCZ. For each patient, disease activity and serological data were evaluated. Moreover, we analysed the evolution of high-resolution computed tomography (HRCT) and pulmonary function tests, including forced vital capacity (FVC) and diffusing capacity of the lung for carbon monoxide (DLCO). Results: Twenty-eight RA-ILD patients were identified (females/males 18/10, mean age 61.6 years), with a mean follow up for TCZ therapy of 30 months. At the end of follow up, FVC remained stable in 14 (56%) patients, improved in 5 (20%) and worsened in 6 (24%). DLCO remained stable in 14 (56%) patients, improved in 5 (20%) and worsened in 6 (24%), even though in 3 patients DLCO and FVC showed an opposite trend. HRCT remained stable in the majority (25) of cases, worsened in two patients with a usual interstitial pneumonia pattern and improved in only one case with a non-specific interstitial pneumonia pattern. Conclusions: The management of RA-ILD patients remains a critical unmet need. TCZ demonstrated a good safety profile in patients with RA-ILD and a potential effect on the stabilisation of lung involvement.