Belimumab in childhood systemic lupus erythematosus: A review of available data

Mendelian Causes of Autoimmunity: the Lupus Phenotype

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that is characterized by its large heterogeneity in terms of clinical presentation and severity. The pathophysiology of SLE involves an aberrant autoimmune response against various tissues, an excess of apoptotic bodies, and an overproduction of type-I interferon. The genetic contribution to the disease is supported by studies of monozygotic twins, familial clustering, and genome-wide association studies (GWAS) that have identified numerous risk loci. In the early 70s, complement deficiencies led to the description of familial forms of SLE caused by a single gene defect. High-throughput sequencing has recently identified an increasing number of monogenic defects associated with lupus, shaping the concept of monogenic lupus and enhancing our insights into immune tolerance mechanisms. Monogenic lupus (moSLE) should be suspected in patients with either early-onset lupus or syndromic lupus, in male, or in familial cases of lupus. This review discusses the genetic basis of monogenic SLE and proposes its classification based on disrupted pathways. These pathways include defects in the clearance of apoptotic cells or immune complexes, interferonopathies, JAK-STATopathies, TLRopathies, and T and B cell dysregulations.

Safety and efficacy of biologics in childhood systemic lupus erythematosus: a critical systematic review

Biologic agents are increasingly being used to treat adult patients with systemic lupus erythematosus (SLE). However, the available data on biologic agents' use in childhood-onset SLE (cSLE) remains limited. To collate available evidence related to the efficacy and safety of using biologic agents in cSLE. The study followed the PRISMA checklist for reporting the data and conducted a thorough search using PubMed, Cochrane Library, and Scopus from January 2005 to August 2023. Only articles meeting specific criteria were included, focusing on cSLE, the use of biologic agents, and having outcome measures at six- and 12-month follow-ups for safety and efficacy. Case reports were excluded, and four independent reviewers screened the articles for accuracy, with a fifth reviewer resolving any discrepancies that arose to achieve a consensus. The final selection included 18 studies with a total of 593 patients treated with biologic agents for severe and/ or refractory cSLE. The most common indication for using biologic agents was lupus nephritis. Rituximab was used in 12 studies, while belimumab was used in six studies. The studies evaluated the efficacy of biologic agents based on SLE disease activity scores, laboratory parameter improvements, and reduced corticosteroid dosage. Positive outcomes were reported, with improvements in renal, hematologic, and immunologic parameters along with mild adverse effects, mostly related to mild infections and infusion reactions. Belimumab and rituximab have shown promise as potential treatments for severe and refractory cSLE cases, leading to decreased disease activity and complete or partial remission in many patients with an acceptable safety profile. However, further research is needed to better understand their benefits and potential risks in these patients. Key Points • This review emphasizes the lack of sufficient randomized controlled trials exploring the use of biologics in childhood systemic lupus erythematosus (cSLE). • Treatment plans for cSLE are being derived from those used for adult systemic lupus erythematosus. • According to current evidence, belimumab and rituximab can be potential treatment options for refractory and severe cases of cSLE. • Additional studies are required to reach more definitive conclusions.

Current views on lupus in children

PURPOSE OF REVIEW

This manuscript provides an update on clinical and pathophysiological features of juvenile-onset systemic lupus erythematosis (jSLE), challenges applying adult-derived classification criteria, and recent advances in treatment and care.

RECENT FINDINGS

Significant scientific advances have improved the understanding of genetic factors (both genetic causes and risk alleles) and associated phenotypic features. Panels of urine/blood biomarker candidates aid in diagnosing jSLE, monitoring disease activity and predicting treatment response. Available classification criteria have been extensively assessed, with differences in clinical and immunological phenotypes of patients across age groups and ethnicities affecting their performance in jSLE. Therapeutic options remain limited and are based on protocols for adult-onset SLE patients. International efforts to inform development of a treat-to-target (T2T) approach for jSLE have yielded cohort-level evidence that target attainment reduces the risk of severe flare and new damage, and treatment compliance.

SUMMARY

Recent studies have significantly improved our understanding of jSLE pathogenesis, highlighting important differences between jSLE and adult SLE, and providing the basis of biomarker development and target-directed individualized treatment and care. Future work focused on development of a T2T approach in jSLE is eagerly awaited.

Efficacy and safety of belimumab for the treatment of refractory childhood-onset systemic lupus erythematosus: A single-center, real-world, retrospective study

Objective

This study aimed to investigate the efficacy and safety of belimumab for treating children with refractory childhood-onset systemic lupus erythematosus (cSLE).

Methods

Twenty-six cSLE patients who received belimumab treatment in our hospital from January 2020 to September 2021 (23 of them for more than 52 weeks) were enrolled in this study. Their clinical and laboratory data, assessment of disease activity, glucocorticoid dosage, and treatment-emergent adverse events (TEAEs) were retrieved for analysis. The paired samples t-test and the nonparametric test were used to compare the baseline and post-treatment data.

Results

The mean age of onset was 10.3 ± 2.4 years old; the mean disease duration was 41.6 ± 37.4 months; the median Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score was 10 (P ₂₅, P ₇₅: 3, 17); and the mean Physician's Global Assessment (PGA) score at baseline was 1.9 ± 1.0. Compared with the baseline values, there was a significant decrease in the 24-h urine protein quantifications at 24 and 52 weeks of treatment (P<0.05) as well as an elevated complement (C) 3 and C4 levels at 4, 12, 24, and 52 weeks of treatment. In addition, the SLEDAI-2K and PGA scores as well as the percentage of CD19⁺ B cells were significantly decreased at 12, 24, and 52 weeks of treatment compared with the baseline values (P<0.05). The dosage of glucocorticoid at 4, 12, 24, and 52 weeks of treatment was significantly less than that at baseline or the previous follow-up (P<0.05). At 52 weeks, 14 subjects (53.8%) achieved Lupus Low Disease Activity State (LLDAS), and 4 subjects (15.4%) reached clinical remission (CR). At the last follow-up, 16 subjects (61.5%) achieved LLDAS, and 10 subjects (38.5%) reached CR.

Conclusions

Belimumab treatment can significantly improve laboratory indicators, reduce disease activity, and decrease the dosage of glucocorticoid required in children with cSLE. Moreover, it has a good safety profile.