Early belimumab in lupus nephritis: Retrospective analysis

Results from a retrospective, multicenter, propensity-matched cohort study comparing early belimumab plus standard of care (SoC) vs SoC alone in 182 adults with lupus nephritis (LN) were published in Rheumatology by Gatto et al. Patients (N = 182; n = 91 in each arm) were matched on baseline proteinuria, estimated glomerular filtration rate, histological class, and initial immunosuppression. The primary endpoint was complete renal response (CRR). 

Key data: At 6 months, the CRR rate was significantly higher with belimumab + SoC vs SoC alone (35.9% vs 16.5%; odds ratio [OR], 2.81; 95% confidence interval [CI], 1.30–6.29; p = 0.005), with a shorter median time to CRR (5.64 vs 7.92 months; p < 0.01). At the time of CRR, glucocorticoid (GC) dose was significantly lower with belimumab + SoC vs SoC alone (5 vs 15 mg/day; p = 0.018). Independent predictors of earlier CRR were belimumab use (hazard ratio [HR], 1.70; 95% CI, 1.11–2.62; p = 0.016) and baseline proteinuria (HR, 0.89; 95% CI, 0.80–0.98; p = 0.019). 

Key learning: Early belimumab integration into SoC accelerates CRR and reduces GC exposure in patients with LN. These real-world findings support upfront combination therapy, particularly in patients with high disease activity.