PO:24:063 | Interstitial lung disease in idiopathic inflammatory myopathy patients: efficacy and safety of nintedanib

Objectives. Idiopathic inflammatory myopathies (IIMs) are systemic autoimmune diseases, often complicated by interstitial lung disease (ILD), a leading cause of morbidity and mortality. This study aims to assess nintedanib (NTD) efficacy and safety in IIM-ILD.Methods. Out of our IIM cohort, 9 IIM-ILD patients were identified and retrospectively evaluated at 12 months prior NTD introduction, at baseline, at 6 and 12 months after NTD. The following variables were recordedm: pulmonary function tests, CPK, aldolase, troponine, NT-proBNP and chest high-resolution CT scans. Immunosuppressive therapies, ILD progression, treatment suspension and adverse events were also evaluated. Progression was defined as a drop in forced vital capacity (FVC) >=10 %predicted within 12 months.Results. Of these 9 IIM-ILD patients treated with NTD, 67% were males, median age 65 (55–74) years, median disease duration 7 (5–16) years (baseline features in Table 1); 78% were positive for anti-synthetase antibodies. In all patients, NTD was combined with immunosuppressive therapies (Table 1), the most commmon one being mycophenolate (MMF), while 2 (22.2%) were on triple immunosuppression with MMF and rituximab (RTX). The majority (67%) had a NSIP pattern at HRCT, and 56% showed >20% parenchymal involvement at baseline CT. In the 12 months prior to NTD (Table 2), %FVC showed a significant decline (p=0.037, 9 patients), with 3 (33%) progressors. At 6 months, a slight but rather significant %FVC improvement was observed (p=0.021, 7 patients). Similarly, at 12 months, %FVC was significantly improved (p=0.047, 4 patients), with the number of progressors reaching zero at both timepoints. Surprisingly, %DLCO mirrored %FVC trends, in particular at 12 months (Table 2). Among patients with former or active myositis (89%), CK values significantly increased in the 12 months prior to NTD (p=0.039), then reduced at 6 months (p=0.009) and stabilized at 12 months (p=0.060). Among patients with myocardial involvement (33%, 3), troponin and NT-proBNP showed no significant changes (Table 2). At baseline, 78% (7) of patients were on prednisone, median dose 5 (5–7.5) mg. At 6 months, the % went down to 67% (6) (p=0.598), with a significant median dose reduction (p=0.045); the median dose was stabilized at 12 months. The most common adverse event was diarrhea (78%), followed by infections (33%); 1 patient developed viral pneumonia requiring hospitalization, and 2 had UTIs. Five (56%) required NTD dose reduction after a median of 8 (4–24) weeks, 3 (33%) due to diarrhea and 2 (22%) due to liver enzyme abnormalities. NTD was discontinued in 2 patients after a median of 10 (9–11) months, mainly due to diarrhea.Conclusions. Our study confirms NTD efficacy in combination with immunosuppressants, thus improving lung function in IIM-ILD patients. Interestingly, NTD allowed also a steroid-sparing effect while adverse events were in line with those of previously published studies.