Effects of Belimumab (BEL) on Renal Outcomes in Patients (pts) With Relapsed and Newly Diagnosed Active Lupus Nephritis (LN)

Despite standard therapy (ST) for LN, only 20–40% of pts achieve complete renal response (CRR) at 0.5–1 year and 20–25% relapse in 3–5 years. The aim of this study was to assess effects of BEL on renal outcomes in relapsed and newly diagnosed pts with LN. Post hoc analysis of the Phase 3, randomized, double-blind, 104-week BLISS-LN study (GSK BEL114054; NCT01639339). Pts with active LN received monthly intravenous (IV) BEL 10 mg/kg or placebo (PBO) + ST. Randomization was stratified by induction regimen: high dose corticosteroids (HDCS) + cyclophosphamide (CYC), followed by azathioprine + low-dose corticosteroids (LDCS), or HDCS + mycophenolate mofetil (MMF), followed by MMF + LDCS. We assessed primary efficacy renal response (PERR; uPCR ≤0.7; eGFR no more than 20% below pre-flare value or ≥60 ml/min/1.73m2; no rescue therapy) and CRR (uPCR <0.5; eGFR no more than 10% below pre-flare value or ≥90 ml/min/1.73m2; no rescue therapy) at Week 104 and time to renal-related event or death in relapsed vs newly diagnosed pts. Of 446 pts included in this analysis, 150 had relapse of LN and 296 were newly diagnosed. Positive effects of BEL vs PBO on PERR and CRR were noted in both subgroups and were numerically greater in relapsed vs newly diagnosed pts (Table). BEL-treated pts had a lower risk at any time of experiencing a renal-related event or death vs PBO in both subgroups ( Table 1 ). These data suggest BEL improved PERR and CRR rates more potently in relapsed pts, in which PERR and CRR were substantially less frequent compared with newly diagnosed LN.