Efficacy of belimumab in patients with systemic lupus erythematosus from North East Asia: Results of exploratory subgroup analyses

ABSTRACT Objectives To assess belimumab efficacy in patients from North East Asia (NEA) with systemic lupus erythematosus (SLE) in baseline demographic/disease characteristic subgroups. Methods This analysis of patient subgroups from BLISS-NEA (GSK Study 113750; NCT01345253) studied adults with SLE randomized to belimumab (10 mg/kg intravenous) or placebo. Primary endpoint, SLE Responder Index 4 (SRI-4) response rate at Week 52, was analysed in subgroups defined by gender, country, prednisone-equivalent dose, concomitant medications, Safety of Estrogens in Lupus National Assessment-SLE Disease Activity Index (SELENA-SLEDAI) score, complement (C) levels, anti-double-stranded deoxyribonucleic acid (dsDNA) positivity, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index score. Results Patients (overall population: N = 677; belimumab: n = 451, placebo: n = 226) were from China (76.4%), Korea (14.8%), and Japan (8.9%). The mean age was 32.1 years; 92.9% were female. In the overall population, more belimumab (53.8%) than placebo (40.1%) patients were SRI-4 Week 52 responders (p = .0001). SRI-4 response rates by subgroups were generally consistent with the overall population. A greater response with belimumab was seen in patients with a baseline SELENA-SLEDAI score ≥10 versus ≤9 and patients with low C3/C4 levels and anti-dsDNA positive at baseline versus those ‘NOT’ (low C3 and/or C4 and anti-dsDNA positive). Conclusions These findings continue to support the efficacy of belimumab in SLE.