FRI0584 EFFICACY AND SAFETY OF RITUXIMAB FOR INDUCTION OF REMISSION AND MAINTENANCE OF IGG4-RELATED DISEASE: EXPERIENCE FROM AN ITALIAN NATIONAL REFERRAL CENTRE
Authors: Corrado Campochiaro, Emanuel Della Torre, Marco Lanzillotta, Enrica Bozzolo, Elena Baldissera, Lorenzo Dagna
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> IgG4-related disease(IgG4-RD) is a systemic fibro-inflammatory disease. Treatment is based on corticosteroids(CS) but up to 50% of patients may relapse. Rituximab(RTX) has emerged as an effective treatment option[1]. <h3>Objectives</h3> To assess the free relapse rate(FRR) in patients receiving or not maintenance RTX therapy. Secondary outcomes: time to relapse, incidence of adverse events and differences in FRR between Group 2a and 2b patients. <h3>Methods</h3> Data of IgG4-RD patients treated with RTX and followed-up for &gt;18 months were reviewed. Patients were treated with two 1 g RTX doses 15 days apart(standard dose,SD) and then divided into: patients receiving RTX in case of relapse(Group 1) and patients receiving maintenance RTX treatment 6 monthly(Group 2). Patients in Group 2 received a first maintenance treatment RTX SD and were then further divided into patients receiving RTX SD(Group 2a) or single 1 g RTX dose(Group 2b). <h3>Results</h3> 14 IgG4-RD patients were included. Median number of organs involved was 3(1-5). Baseline median physician global assessment(PGA) was 70(50-90), IgG4-RD responder index(IgG4-RD RI) 12(6-12). Median eosinophil count, ESR, CRP, and serum IgG4 level were 100cells/μL(50–1.800), 19mm/h(6-64), 3.7mg/L(0.1–36) and 3.17mg/L(470–21.800) respectively. Indications for RTX were: relapse in 10/14(71%), partial response in 3/14(21%) and first-line treatment in 1(7%) patient. CS were stopped in 5 patients and reduced by month 3 in remaining patients(27.14±13.06 vs 6.43±2.45 mg daily,p=0.012). 3 patients were on concomitant methotrexate(MTX) therapy at RTX induction, MTX was stopped in all patients at month 3. At month 6 PGA, IgG4-RD RI, and serum IgG4 decreased to a median value of 10(0-50), 2(0-6), and 822 mg/L(380–7.313), respectively(p&lt;0.001 for all comparisons). Median eosinophil count, CRP and ESR levels did not change significantly. 8(57.1%), 5(35.7%) and 1 patient(7%) were on disease remission (DR), complete remission(CR), and partial remission(PR), respectively. Median number of RTX courses was 2(1–2) in Group 1, 3(3–7) in Group 2a, and 4(3–5) in Group 2b. Organ involvement, PGA, IgG4-RD RI, ESR, CRP, and serum IgG4 levels were not significantly different between the 2 Groups at baseline. FRR at 18 months in Group 1 was significantly lower than that in Group 2(29%vs100%,p=0.006). 5(71%) patients in Group 1 relapsed on average 9(7–12)months after RTX induction. 2(14%) patients had hypersensitivity reactions during RTX induction. 6(43%) patients, 3 in Group 1 and 3 in Group 2, experienced low-grade infections. <h3>Conclusion</h3> RTX is a safe and effective treatment in IgG4-RD. Both SD and single 1 g RTX dose seem effective in maintenance. <h3>References</h3> [1] CarruthersMN.Rituximab for IgG4-related disease:a prospective,open-label trial.Ann Rheum Dis.2015. <h3>Disclosure of Interests</h3> Corrado Campochiaro Consultant for: Dr Corrado Campochiaro received consultation honoraria from Pfizer., Emanuel Della Torre: None declared, Marco Lanzillotta: None declared, Enrica Bozzolo: None declared, Elena Baldissera Consultant for: Consultation honoraria from Novartis and Rottapharm, Speakers bureau: Pfeizer, Sobi, Novartis, Lorenzo Dagna Consultant for: Prof Lorenzo Dagna received consultation honoraria from Abbvie, Amgen, Biogen, Bristol-Myers Squibb, Celltrion, Novartis, Pfizer, Sanofi-Genzyme, and SOBI.