Background Systemic Lupus Erythematosus (SLE) is a chronic disease requiring long-term treatment. Even though immunosuppresive therapy has significantly improved the survival, a great percentage of SLE patients exhibit a persistently active disease or deal with disease flares during the follow-up. Belimumab (BLM), an anti-B Lymphocyte Stimulator (BLyS), is currently the only biological drug approved for the treatment of active SLE patients not responding to standard of care, without active kidney or neuropsychiatric involvement.
Objectives Aim of the study was to analyse 12 months survival of BLM treatment and causes of withdrawal in a monocentric cohort of SLE patients followed-up in a daily practice setting.
Methods The study was proposed to all the patients who were due to start BLM. After the informed consent was obtained, demographic, clinical and serological data, indication to BLM and concomitant therapies were registered. At baseline and after 3, 6 and 12 months of follow-up, disease activity (SLE Disease Activity Index – SLADAI 2K), C3 and C4 levels, anti-dsDNA status and weekly dose of glucocorticoids were recorded. At each visit adverse events and causes of withdrawal were also evaluated. Data were expressed as mean±standard deviation; after 3, 6 and 12 months, difference in SLEDAI 2K, C3 and C4 and prednisone-equivalent dose compared to baseline were evaluated by Student t test. The treatment survival was evaluated by Kaplan-Meier analysis. P value <0.05 were considered significant.
Results We enrolled to the study 15 Caucasian females with mean age of 41.3±10.1 years and mean disease duration of 19.2±9.2 years. Indication for starting BLM were: mucocutaneous involvement (n=5, 33.3%), arthritis (n=10, 66.7%) and lung involvement (1 patient, 6.7%). At baseline, all the patients were taking prednisone; 88.7% hydroxychloroquine, 33.3% mycophenolate mofetil, 20% azathioprine, 20% cyclosporine, 20% methotrexate and 6.7% thalidomide. Table 1 summarizes the trend of SLEDAI 2K, C3 and C4, prednisone dose and percentage of patients positive for anti-dsDNA during the follow-up.
The Kaplan-Meier (Figure 1) shows a 12 months survival rate of 60%. In 13.3% of patients adverse events were the cause of BLM withdrawal (severe infection in one patient and acute infusion reaction in another one). In 2 patients (13.3%) BLM was discontinued for lack of efficacy on articular and skin manifestations, after 4 and 8 months respectively; one patient developed a severe neuropsychiatric flare after the second BLM infusion and was admitted in our hospital for depression and suicidal thoughts. The other patient was lost during the follow-up.
Conclusions In our monocentric cohort of SLE patients treated in a real life setting, the main causes of BLM withdrawal were the lack of efficacy or disease flare.
Disclosure of Interest None declared