RT Journal Article SR Electronic T1 AB0534 TREATING SYSTEMIC LUPUS ERYTHEMATOSUS IN THE 21ST CENTURY: COMBINING RITUXIMAB WITH BELIMUMAB JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 1465 OP 1466 DO 10.1136/annrheumdis-2023-eular.4260 VO 82 IS Suppl 1 A1 Issayeva, B. A1 Mesnyankina, A. A1 Aseeva, E. A1 Solovyev, S. A1 Nikishina, N. A1 Issayeva, S. A1 Saparbayeva, M. A1 Amanzholova, A. A1 Razikhova, A. A1 Аbdulgaziz, A. YR 2023 UL http://ard.bmj.com/content/82/Suppl_1/1465.2.abstract AB Objectives efficacy of combination therapy with rituximab and belimumab in patients with systemic lupus erythematosus.Methods The study included 15 SLE pts (1М/14F) criteria with high (SLEDAI2K≥10 – 12pts.) and moderate (SLEDAI2K<10- 3pts.) disease activity; out of them 4 patients had lupus nephritis, 2- vasculitis. 1 pts had kidney damage, cerebrovasculitis and vasculitis. All patients fulfilled the Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) disease classification criteria [1] for SLE Others have predominantly mucocutaneous and articular manifestations of SLE. The dose of oral glucocorticoids (GC) was: 60 mg in one patient with vasculitis, LN, cerebrovasculitis, and one patient with vasculitis received 20 mg of prednisone; in 11 patients from 10 to 5 mg; in 2 patients without oral glucocorticoids. All patients with SLE with kidney damage and vasculitis received mycophenolate mofetil or cyclophosphamide. Rituximab (RTM) was administered at a dose of 500-2000 mg, followed by the addition of belimumab (BLM) after 1-6 months at a standard dose of 10 mg/ kg once a month - a total of 7 infusions. The following parameters were evaluated: the effectiveness of therapy, the concentration of autoantibodies, the dose of oral corticosteroids initially at the time of RTM administration and then every 3 months after the initiation of BLM therapy.Results 13 pts demonstrated the decrease in clinical and laboratory SLE activity, starting from 3mo of follow-up. After the start of BLM infusions, a decrease in SLE activity was observed in all patients. Among them, 10 had SLEDAI-2K activity of less than 4 points. SLEDAI-2k Me 10 [10;16], after treatment of RTM and BLM 4[2;6]. Only one patient (№4) had an relapse of SLE, due to the delay in receiving the infusion of BLM. He was receiving standard GC doses. In dynamics, a decrease anti-double DNA titres (Me 101 [36;200]U/ml vs 28 [8;67]Ед/мл), С3 (0,49 [0,42;0,78]g/l vs 0,71 [0,59;0,87] g/l), С4 (0,06 [0,045;0,1] g/l vs 0,12 [0,07;0,14] g/l) was registered. The GC dose was reduced in most patients (Table 1), but the previously prescribed immunosuppressive therapy continued. There were no cases of severe infection. We have not detected any new organ damage.View this table:Table 1. Dose of oral glucocorticoids, mgConclusion Combination therapy allows to gain control over disease activity in short time, due to the effect of RTM, while added BLM provides further prolongation of the effect achieved, minimizing the risk of flare. The use of such therapy contributes to a rapid and effective reduction in the activity of the disease, improvement of laboratory markers of SLE (at to ds-DNA, C3, C4), the use of lower doses of oral GCs. This combination may be used as a method of choice in pts with severe SLE involving vital organs, and in persistent cutaneous-articular disease and high immunological activity.Reference [1]Petri, M., et al. Derivation and validation of the Systemic Lupus International Collaborating Clinics classification criteria for systemic lupus erythematosus. Arthritis & Rheumatism 64.8 (2012): 2677-2686Acknowledgements: NIL.Disclosure of Interests None Declared.