AB0463 BELIMUMAB IV EFFECT IN GLUCOCORTICOID TREATMENT IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS

Background: Systemic lupus erythematosus (SLE) is an autoimmune chronic disease produced by aberrant immunological response that consequently, causes a widespread organic damage. Treatment leads to regulating this disrupted immunological response. As a result, in 2011 Belimumab was approved for adults patients diagnosed with SLE, what is a monoclonal human antibody whose target is a B-lymphocyte stimulator (BLyS), a protein involved in the disease pathogeny. Objectives: To evaluate the glucocorticoesteroid dose variation in adult patients with systemic lupus erythematosus during Belimumab IV treatment. Methods: Retrospective, observational study that includes patients diagnosed with SLE according to SLICC 2012 criteria, who are treated with Belimumab IV. Treatment has been administrated as an initial dose: 10 mg/kg every 14 days and then, a maintenance dose: 10 mg/kg every 28 days. Data form serological profile, clinical manifestations at diagnoses and at the onset of treatment, existence of comorbidities or other diseases, concomitant therapy directed to the main disease or to the complications that came from the disease, non administration causes and definitive treatment discontinuation were collected from July 2012 until December 2018. Results: A total of 19 patients (94.74% women) with 28 years old (Q1 14, Q3 31.82) as a median age at diagnosis and 11 (Q1 6.5, Q3 20) years since disease diagnosis were included. Follow up mean was 29 (Q1 7.5, Q3 37) months. Regards to concomitant therapies, 5 patients (26.31%) were treated with Azatioprine and 3 patients with Methotrexate (15.79%). At the onset of biological therapy, 17 patients were treated with glucocorticoids, at a dose of 10 mg (Q1 9.38, Q3 10.63). At the end of follow up, 18 patients (94.73%) were treated with corticoid and the mean dose was 8.75 mg (Q1 8.75, Q3 8.75). We observed a mean corticoid dose reduction of 4.02 mg (Q1 2.5, Q3 5). Dose was not modified in 4 patients after the beginning of Belimumab IV. As exceptions, in 1 patient we added corticoids to treatment (dose of 5 mg/day) and in another one we doubled corticoid dose, until a maximum dose of 20 mg/day. Belimumab treatment was definitive discontinued in 5 patients because of peripheral venous insufficiency, pregnancy, itchy skin lesions, uncertain drug allergy and primary pulmonary hypertension. Conclusion: As we observed, an important percentage of patients (in our sample close to 90%) take usually corticoids, with the clinical consequences and development of comorbidities in a long time and adverse events related to this therapy. Diary dose is reduced in 57.9% of our patients, even in those patients who have discontinued Belimumab treatment, in which we observed a dose reduction too. Disclosure of Interests: None declared