Lupus Low Disease Activity State (LLDAS) discriminates responders in the BLISS-52 and BLISS-76 phase III trials of belimumab in systemic lupus erythematosus

We evaluated the discriminant capacity of the Lupus Low Disease Activity State (LLDAS) in post-hoc analysis of data from the BLISS-52 and BLISS-76 trials of belimumab in systemic lupus erythematosus (SLE).LLDAS attainment, discrimination between belimumab and placebo arms, and the effects in subgroups with high disease activity at recruitment were evaluated at week 52 using appropriate descriptive statistics, χ2 test and logistic regression.At week 52, for belimumab 10 mg/kg, 17.0% and 19.3% of patients who achieved a Systemic Lupus Erythematosus Responder Index-4 also attained LLDAS in BLISS-52 and BLISS-76, respectively. Significantly more patients attained LLDAS on belimumab 10 mg/kg compared with placebo (12.5% vs 5.8%, OR 2.32, p=0.02 for BLISS-52; 14.4% vs 7.8%, OR 1.98, p=0.04 for BLISS-76). In a subgroup analysis, the difference in week 52 LLDAS attainment between belimumab 10 mg/kg and placebo was greater in patients who had higher disease activity at baseline, compared with the overall group.LLDAS was able to discriminate belimumab 10 mg/kg from placebo in the BLISS-52 and BLISS-76 trials. Our findings support the validity of LLDAS as an outcome measure in SLE clinical trials.