Two Year Follow-Up On Biologics Use In 13 Centers-Data From The International Registry For Biologics In Systemic Lupus Erythematosus

Abstract

Background/Purpose: Only one biologic agent has been approved for use in SLE, but some are used off-label in various settings. To obtain systematic information regarding this, members of the SLICC group initiated the International Registry for Biologics in SLE (IRBIS). The entire registry contains data from 28 centers. Here, data are presented from 13 centers for which two-year follow-up was available on patients for whom a biologic was initiated in 2010-2011. The purpose with this study was to analyse the use of biologics in SLE, and assess the results achieved over the first two years after initiation.

Methods: IRBIS investigators provided retrospective data on all patients treated with a biologic for SLE at their center in 2010-2011. Standardized case report forms were used to collect demographic, disease-specific and treatment data at the time of biologic initiation and at yearly follow-ups.

Results: In the entire cohort, 455 patients were treated with rituximab (84%), belimumab (10%), epratuzumab (5%), and anti-tumor necrosis factor agents (abatacept, etanercept and adalimumab, each <1%). The major organ manifestations leading to biologic treatment were lupus nephritis (LN, 44%), hematological (17%), musculoskeletal (16%), skin disease (10%), CNS (4%) and other (9%). Reasons for choosing the biologic were disease-control (73%), steroid-sparing (5%) or both (23%). At biologic initiation mean disease duration (±SD) was 9.5±7.9 years, and mean age was 42.2±12.5. Most patients (91%) were female. Prior to biologic treatment, most patients (91%) had been treated with one or more immunosuppressives (ISs). Just over half (57%) had used 1-2 ISs, 21% had used three, and 13% had used 4-6 ISs.

At two-year follow-up (n=120), SLE disease activity (SLEDAI) and corticosteroid (CS) dose were significantly lower versus baseline (SLEDAI: 9.4±5.3 to 3.1±2.5; CS dose: 10.7±13.9 to 4.8±5.9 mg; mean±SD paired analyses, p<0.0001 for both comparisons). SLICC damage-index remained unchanged.

At baseline, concomitant CS was used in 91% of patients compared to 61% at follow-up. There were six deaths, none attributed to the biologic. In almost half of patients (48%) there was at least one adverse event reported over the indicated follow-up period, of which 5% were attributed to the biologic agent. Serious adverse events included 6 infections, 4 opportunistic infections, posterior reversible encephalopathy syndrome (3), allergic reactions (4).

Conclusion: Rituximab was the biologic used most commonly in this international cohort of patients who were started on biologics in 2010-2011. Biologics were used for a range of SLE manifestations. At two-year follow-up both lupus activity and concomitant corticosteroid dosage had decreased significantly and corticosteroids had been discontinued in 30% of patients.