Objectives To describe patients with Systemic Lupus Erythematosus (SLE) treated with Belimumab (BLM).

Material and methods Review of patients with SLE treated with BLM from 2012 to 2017.

Results We enrolled 18 patients, 16 women and 2 men. The median age at of SLE diagnose was 34.3 (IQR 27–45.7) years and the median age at BLM start was 2.2 (IQR 38.9–47) years. The received sDMARDs median number was 2.5 (IQR 2–4). Before starting BLM 7 patients had received rituximab, 4 cyclophosphamide, 1 abatacept and 1 one efalizumab. At BLM begin 17 patients were taking prednisone, 13 hydroxycloroquine, 7 methotrexate, 1 azatioprine, 1 mycophenolate and 1 leflunomide (table 1).

The median BLM bolus received was 8.5 (IQR 2–32.7) and it was stopped in 4 patients due to lack of efficacy; this 4 patients had persistence of arthritis and non of them had received bDMARD before.

13 patients had at least one antiphospholipid autoantibody positive and 4 developed antiphospholipid syndrome.

The median titer of antinuclear antibodies (ANA) was 1/360 (IQR 1/160–1/1280). All patients but one had ANA positive; among them 9 patients were antiRo positive, 4 antiLa, 4 antiSm and 4 antiRNP positive antibodies. 9 patients were antiDNA positive and 5 were positive for rheumatoid factor (RF) able 1 shows SLEDAI, C3 and C4, antiDNA levels.

At BLMin 5 patients had renal involvement; 3 of them improved after 3 months of treatment. Among 14 patients with joint involvement, 3 improved by month 3, 2 by month 6 and 1 by month 7 after treatment beginning. 3 patients had heart and lung disease; no one of them improved with BLM. Among 9 patients with skin disease only one showed improvement after 12 months of treatment. 9 patients had haematological disorders: 1 improved by month one, 1 by month 3, one by month 5 and 2 my month 6 of treatment.

Conclusion In this series BLM improved SLEDAI and complement levels allowing sparing of maintenance corticosteroid in SLE patients.