AB0507 Belimumab in patients with systemic lupus erythematosus: outcomes in routine clinical practice

Abstract

BackgroundSystemic lupus erythematosus (SLE) is a systemic autoimmune disease with a wide range of clinical manifestations. The persistence of activity of the disease and the prolonged use of corticosteroids are amongst the main predictors of accumulated organ damage in patients with SLE. Therefore, we need new strategies to induce long-lasting remission and minimise the adverse effects of standard medications.Objectivesto assess the effectiveness and safety of Belimumab in actual clinical practice during the first year of treatment in patients with SLE.Methodsretrospective observational study of patients treated with Belimumab. This study involves 6 hospitals in Castilla y León (Spain). It collects clinical and analytical data before the start of Belimumab, and 6 and 12 months after the initiation of the therapy. The data collected include the daily dose of prednisone received at different time points and the activity of the disease was classified as mild, moderate and severe based on SELENA-SLEDAI index. A reduction from baseline of 3 points on the SELENA-SLEDAI indicates meaningful symptomatic improvement.ResultsAmong the twenty-five patients were included, with a mean age of 43.7+12.2 years, 72% were female and 96% caucasian. The average time from diagnosis of SLE to Belimumab infusion was 9.5+7.1 years; 32% were diagnosed with SLE <5 years ago. Up to 56% of the patients had moderate disease activity and only 8% patients had very high activity of the disease. All but one of the patients had previously received an immunosuppressant (azathioprine in 50% of the cases) and 16% of the sample had not responded to rituximab. The most frequent reasons for initiating Belimumab were an ineffective previous treatment regimen (60%), the intend to decrease steroid use (56%), and worsening patient condition (52%); whereas the most frequent manifestation of SLE in these patients were arthritis (44%), followed by mucocutaneous (20%) and immunologic findings (20%). As for immunologic markers of activity, DNA was elevated by 40% and 68% of the patients showed hypocomplementemia, that dropped to 24% in both cases at 12 months. The mean score of the SELENA-SLEDAI index decreased from 9.5 to 6 in the first 6 months and to 5.2 in the 12 months of follow-up. A reduction in the initial mean steroid dose was also observed from 20 mg/day to 8.9 mg/day and 6.4 mg/day at 6 and 12 months respectively. Hence, the dose of steroid was reduced by 68% during the first year (p=0,06). This reduction was clinically significant, but it did not reach statistical significance in our study. Two patients (8%) had discontinued Belimumab within the first 6 months of therapy (1 pregnancy and 1 worsening proteinuria); 34.7% had discontinued it within the first 12 months, mostly due to ineffectiveness (62.5%). Two patients with severe renal involvement (>1 gr proteinuria/24 hour) were treated with Belimumab, allowing to reduce the steroids to a low dosis (<7.5 mg/day) at 12 months.ConclusionsBelimumab appears to be effective, reducing disease activity as m...