# Efficacy of belimumab on extra-renal lupus in patients with lupus nephritis and end-stage renal disease

## TL;DR

Belimumab helps control lupus outside the kidneys in patients with severe kidney disease, reducing steroid use and infections.

## Contribution

Belimumab's efficacy and safety in ESRD-LN patients is evaluated for the first time.

## Key findings

- Belimumab significantly reduced extra-renal SLEDAI scores and improved complement C3 levels.
- Glucocorticoid dosages were markedly reduced in ESRD-LN patients treated with belimumab.
- Mild infections occurred but no severe infections requiring ventilation were reported.

## Abstract

Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE), with approximately 20–30% of LN patients progressing to end-stage renal disease (ESRD) within a decade. Persistent extra-renal SLE activity, cardiovascular events, and infections significantly contribute to adverse outcomes. Current therapeutic strategies primarily rely on glucocorticoids and immunosuppressants; however, the adverse effects of these agents are intensified in ESRD patients. Belimumab, a B-lymphocyte-targeted biologic agent, has demonstrated efficacy in managing SLE but lacks sufficient data regarding its application in ESRD-LN patients. This study aims to evaluate the role of belimumab in controlling extra-renal disease activity, optimizing medication use, and assessing safety in ESRD-LN patients.

This retrospective analysis involved eight LN patients with ESRD (eGFR <15 mL/min/1.73 m2 or on hemodialysis) who received belimumab treatment. Data on SLE manifestations, medications, and laboratory parameters were collected before and after ESRD onset. The primary endpoints included changes in extra-renal Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores, adjustments in prednisone dosages, and the incidence of infection episodes during belimumab therapy.

This study analyzed data from eight ESRD-LN patients treated with belimumab over a median follow-up period of 28.01 ± 14.57 months. Belimumab significantly reduced extra-renal SLEDAI scores (from 6.13 ± 3.09 to 1.50 ± 1.41, p < 0.01) and improved complement C3 levels (from 0.64 ± 0.12 g/L to 0.8 ± 0.16 g/L). Glucocorticoid dosages were markedly reduced (from 21.25 ± 9.64 mg/day to 3.91 ± 3.98 mg/day), with three patients discontinuing glucocorticoid therapy entirely. Mild infections were observed, but no severe infections requiring mechanical ventilation were reported.

Belimumab appears to be a promising therapeutic option for ESRD-LN patients, effectively controlling extra-renal disease activity, reducing glucocorticoid use, and demonstrating a favorable safety profile. Further research is required to optimize dosing strategies and to validate the long-term efficacy and safety of belimumab in this high-risk population.