Belimumab in the treatment of systemic lupus erythematosus with juvenile onset: Results of a single-center retrospective study
Authors: Kaleda Maria I. , Nikishina Irina P. , Pachkoria Tamari N. , Shapovalenko Anna N. 
Published: September 2024

The treatment of systemic lupus erythematosus with juvenile onset (jSLE) remains a difficult task, taking into account the more aggressive course of the disease, requiring the appointment of various therapy regimens, including mainly a combination of high doses of glucocorticoids (GC) with immunosuppressive drugs, which on the one hand improves control by the course of the disease, but on the other hand leads to an increase in serious adverse effects from therapy. Modern therapy capabilities have improved significantly with the advent of the belimumab – first and alone registered biologics for children with SLE.

The aim of the study – based on an open single-center retrospective study, to analyze the efficacy and safety of belimumab in children with SLE.

Material and methods. The study included all patients with jSLE who were observed in the pediatric department of V.A. Na sonova Research Institute of Rheumatology and received at least 1 infusion of belimumab. Diagnosis of SLE based on 2012 SLICC (Systemic Lupus Erythematosus International Collaborating Clinics) criteria. The efficacy of therapy was evaluated among patients who received belimumab for 6 months or more, and safety in all who received at least 1 infusion.

Results. The study included 31 patients, 24 girls/7 boys. The median (Me) age at onset of the disease was 12.6 [10.18; 13.5] years, the Me duration of the disease at the time of initiation of belimumab therapy was 2.15 [0.9; 4.4] years. The Me activity on the SLEDAI (Systemic Lupus Erythematosus Disease Activity Index) at the time of diagnosis verification was 12 [9; 17.5], at the time of start of belimumab – 8 [6; 12], 35.5% patients had severe activity, 51.6% – moderate, 12.9% – mild activity. The dose of GC per os at start of belimumab was 15 [10; 21.25] mg/day, 32.26% of patients received a high dose of GC, 54.84% – moderate dose, 12.9% – low dose. 9 patients had SDI (Systemic Lupus International Collaborating Clinics Damage Index) ≥1, Me – 1 [1; 2]. After 6 months of therapy, the Me of disease activity according to SLEDAI was 4 [2; 6], the dose of GC per os was reduced to 10 [8.25; 17.5] mg/day. In 15 patients, a decrease in antiDNA was recorded (57.7% of those who initially had elevated values of antiDNA), in 9 the level of complement was normalized (50% of those who initially had hypocomplementemia). After 12 months of therapy, the Me of SLEDAI was 4 [2; 4] (p=0.034), the dose of GC per os was 5 [5; 8.125] mg/day (p=0.012). 5 patients completed therapy within 12 months or more: 1 patient – remission, 4 patients – secondary inefficiency. Belimumab treatment was well tolerated, with the exception of three cases of serious adverse reactions (9.7%): prolonged diarrheal syndrome (after the 1st infusion), Lyell’s syndrome (after the 2nd infusion), infusion reaction (during the 2nd infusion). During the therapy of belimumab, no new damage were recorded; in 2 patients there was a decrease in the SDI.

Conclusion. Belimumab therapy in patients with jSLE demonstrated high efficacy with a decrease in the activity of the disease according to SLEDAI, normalization of antiDNA and complement, the possibility of a significant reduction the dose of GC, the absence of progression of the SDI with a good safety profile in the vast majority of patients.