Clinical Phenotype In Scleroderma Patients With Anti-Topoisomerase I Positivity And Limited Cutaneous Form: Data From The Eustar Database

Background:There is renewed interest in the role of autoantibodies to predict outcomes in systemic sclerosis (SSc). Among the newly identified subsets, patients with limited cutaneous form (lcSSc) but anti-topoisomerase I antibodies (Scl70) positivity draw particular attention, and namely, assessing the risk of developing interstitial lung disease (ILD) —the main cause of death in SSc—to improve the management of Scl70-lcSSc patients.Objectives:We aimed to characterize patients with Scl70-lcSSc in the large multicenter European Scleroderma Trial and Research (EUSTAR) cohort.Methods:The EUSTAR database was locked in July 2019. We included all patients fulfilling 1980 ACR and/or 2013 ACR/EULAR criteria for SSc, with disease duration at database entry ≤3 yrs and known and stable skin form during the first 3 yrs. Patients with lcSSc were compared: Scl70-lcSSc (target group) vs. ACA-lcSSc and ANA-lcSSc (Step 1); and Scl70-lcSSc vs. Scl70-dcSSc (Step 2). In the ANA subgroup we included ANA+ patients with negative SSc-specific antibodies (Scl70, ACA, RNA polymerase III). In each step, we performed 5 generalized mixed models (GMM) for the risk of the new onset of ILD (defined by imaging), primary myocardial involvement (PMI), pulmonary hypertension (PH), “any severe” (ILD+PMI+PH+scleroderma renal crisis) and all-cause-mortality. An additional GMM assessed the risk of forced vital capacity (FVC) decline ≥10% vs. FVC value at ILD onset. Each GMM was adjusted for age, sex and confounders.Results:Overall, 1285 SSc patients were included: 1068 (83%) females, 860 (67%) lcSSc and 425 (33%) dcSSc. Among patients with lcSSc, 537 (62%) had ACA+, 194 (23%) Scl70+ and 129 (15%) ANA+; 425 patients had dcSSc and Scl70+. Median follow-up was similar in all 4 groups: 7.2 to 8.1 yrs.Step 1: At baseline, Scl70-lcSSc patients had significantly shorter time from Raynaud’s phenomenon (RP) to SSc onset, higher mRSS (5.8±4.8 vs. 4.3±4, p=0.001), and higher rate of articular and muscular involvement vs. ACA-lcSSc patients (Figure 1). No differences were found between Scl70-lcSSc and ANA-lcSSc comparing the aforementioned variables. ILD was more frequent in Scl70-lcSSc (46%) than in ACA-lcSSc (10%) and ANA-lcSSc (25%), as well as restrictive lung disease. GMM showed that Scl70-lcSSc carries a higher risk of ILD than both ACA-lcSSc (HR 4.55, 95%CI 3.23-6.67) and ANA-lcSSc (HR 2.17, 95%CI 1.39-3.45), with a rate of FVC decline ≥10% over time similar to the other limited forms. In Scl70-lcSSc patients the risk of “any severe” organ involvement was similar to ANA-lcSSc and higher than ACA-lcSSc (HR 1.89, 95%CI 1.40-2.50). In particular, Scl70-lcSSc shows a risk of PMI similar to ANA-lcSSc and lower than ACA-lcSSc; no differences regarding PH risk. The mortality risk in patients with Scl70-lcSSc was similar to the other limited forms’.Step 2: At baseline, time from RP to SSc onset was longer in patients with Scl70-lcSSc, with less frequent joint synovitis and tendon friction rubs vs. patients with Scl70-dcSSc. Conversely, the frequency of muscular, cardiac and pulmonary involvement was similar. The risk of ILD in Scl70-lcSSc patients was similar to Scl70-dcSSc, with a lower risk of FVC decline ≥10% over time. The risk of “any severe” involvement (HR 0.66, 95%CI 0.49-0.83), PMI and PH was lower and the mortality risk tended to be lower (HR 0.57, 95%CI 0.33-1.01, p=0.053) vs. Scl70-dcSSc.Conclusion:In our large multicenter EUSTAR cohort one quarter of lcSSc patients were Scl70+. We show a ranking for major organ involvement within lcSSc: Scl70 the most severe, ANA+ intermediate and ACA the milder form. Scl70-dcSSc patients present the most severe phenotype, and Scl70 positivity, more than the cutaneous subset, is strongly predictive of ILD, whereas other variables may influence progression. These results may provide new insight to improve the management of Scl70-lcSSc patients.Disclosure of Interests:Elisabetta Zanatta: None declared, Dörte Huscher: None declared, Paolo Airò: None declared, Alexandra Balbir-Gurman: None declared, Elise Siegert: None declared, Augusta Ortolan: None declared, Marco Matucci-Cerinic: None declared, Franco Cozzi: None declared, Gabriela Riemekasten: None declared, Anna-Maria Hoffmann-Vold: None declared, Oliver Distler Speakers bureau: has/had consultancy relationship and/or has received research funding in the area of potential treatments for systemic sclerosis and its complications from (last three years): Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Baecon Discovery, Blade Therapeutics, Bayer, Boehringer Ingelheim, ChemomAb, Corbus Pharmaceuticals, CSL Behring, Galapagos NV, Glenmark Pharmaceuticals, GSK, Horizon (Curzion) Pharmaceuticals, Inventiva, iQvia, Italfarmaco, iQone, Kymera Therapeutics, Lilly, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Novartis, Pfizer, Roche, Sanofi, Serodapharm, Topadur, Target Bioscience and UCB. Patent issued “mir-29 for the treatment of systemic sclerosis” (US8247389, EP2331143)., Consultant of: has/had consultancy relationship and/or has received research funding in the area of potential treatments for systemic sclerosis and its complications from (last three years): Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Baecon Discovery, Blade Therapeutics, Bayer, Boehringer Ingelheim, ChemomAb, Corbus Pharmaceuticals, CSL Behring, Galapagos NV, Glenmark Pharmaceuticals, GSK, Horizon (Curzion) Pharmaceuticals, Inventiva, iQvia, Italfarmaco, iQone, Kymera Therapeutics, Lilly, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Novartis, Pfizer, Roche, Sanofi, Serodapharm, Topadur, Target Bioscience and UCB. Patent issued “mir-29 for the treatment of systemic sclerosis” (US8247389, EP2331143)., Grant/research support from: Kymera Therapeutics, Mitsubishi Tanabe, Armando Gabrielli: None declared, Stefan Heitmann: None declared, Nicolas Hunzelmann: None declared, Carlomaurizio Montecucco: None declared, Jadranka Morovic-Vergles: None declared, Camillo Ribi: None declared, Andrea Doria: None declared, Yannick Allanore: None declared