Abstract
OBJECTIVE: The Lupus Foundation of America Rapid Evaluation of Activity in Lupus (LFA-REAL) system is a novel and simple SLE disease activity instrument, consisting of a tandem clinician-reported (ClinRO) and patient-reported (PRO) outcome measure. The aim of this study was to compare the LFA-REAL system with other SLE activity measures in the phase III trial of ustekinumab in patients with active SLE. METHODS: This was a prespecified analysis of data from a randomised, double-blind, placebo-controlled, parallel-group trial conducted at 140 sites in 20 countries. Correlations were evaluated between the LFA-REAL ClinRO and PRO with a panel of clinician-reported and patient-reported disease activity measures commonly used in SLE clinical trials at baseline, week 24 and week 52. All p values are reported as nominal. RESULTS: Trial participants included 516 patients with SLE with a mean (SD) age of 43.5 (8.9), of whom 482 (93.4%) were female. The LFA-REAL ClinRO correlated with Physician Global Assessment (r=0.39, 0.65 and 0.74, p<0.001), British Isles Lupus Assessment Group Index (r=0.43, 0.67 and 0.73, p<0.001) and SLE Disease Activity Index-2000 (r=0.35, 0.60 and 0.62, p<0.001). The LFA-REAL ClinRO arthralgia/arthritis score correlated well with active joint counts (r=0.54, 0.73 and 0.68, p<0.001) and the mucocutaneous global score correlated strongly with Cutaneous Lupus Erythematosus Disease Area and Severity Index total activity (r=0.57, 0.77 and 0.81, p<0.001). The LFA-REAL PRO demonstrated a moderate correlation with Functional Assessment of Chronic Illness Therapy-Fatigue (r=-0.60, -0.55 and -0.58, p<0.001), Lupus QoL physical health (r=-0.42, -0.47 and -0.46, p<0.001), SF-36v2 vitality (r=-0.40, -0.43 and -0.58, p<0.001) and SF-36v2 Physical Component Summary (r=-0.45, -0.53 and -0.53, p<0.001). The LFA-REAL ClinRO and PRO showed a moderate correlation with each other (r=0.32, 0.45 and 0.50, p<0.001). CONCLUSIONS: The LFA-REAL ClinRO and PRO showed varied levels of correlations (weak to strong) with existing physician-based lupus disease activity measures and patient-reported outcome instruments, respectively and were able to more accurately capture organ-specific mucocutaneous and musculoskeletal manifestations. More analyses are needed to determine areas in which patient-reported outcomes are most similar or different to physician-reported end points and the basis for differences.