What Does It Mean to Be a British Isles Lupus Assessment Group–Based Composite Lupus Assessment Responder? Post Hoc Analysis of Two Phase III Trials

OBJECTIVE: The British Isles Lupus Assessment Group–based Composite Lupus Assessment (BICLA) is a validated global measure of treatment response in systemic lupus erythematosus (SLE) clinical trials. To understand the relevance of BICLA in clinical practice, we investigated relationships between BICLA response and routine SLE assessments, patient‐reported outcomes (PROs), and medical resource utilization. METHODS: This was a post hoc analysis of pooled data from the phase III, randomized, placebo‐controlled, 52‐week TULIP‐1 (ClinicalTrials.gov identifier: NCT02446912; n = 457) and TULIP‐2 (ClinicalTrials.gov identifier: NCT02446899; n = 362) trials of intravenous anifrolumab (150/300 mg once every 4 weeks) in patients with moderate‐to‐severe SLE. Changes from baseline to week 52 in clinical assessments, PROs, and medical resource use were compared in BICLA responders versus nonresponders, regardless of treatment assignment. RESULTS: BICLA responders (n = 318) achieved significantly improved outcomes compared with nonresponders (n = 501), including lower flare rates, higher rates of attainment of sustained oral glucocorticoid taper to ≤7.5 mg/day, greater improvements in PROs (Functional Assessment of Chronic Illness Therapy–Fatigue, Short Form 36 Health Survey), and fewer SLE‐related hospitalizations/emergency department visits (all nominal P < 0.001). Compared with nonresponders, BICLA responders had greater improvements in global and organ‐specific disease activity (Physician’s Global Assessment, SLE Disease Activity Index 2000, Cutaneous Lupus Erythematosus Disease Area and Severity Index Activity, and joint counts; all nominal P < 0.001). BICLA responders had fewer lupus‐related serious adverse events than nonresponders. CONCLUSION: BICLA response is associated with clinical benefit in SLE assessments, PROs, and medical resource utilization, confirming its value as a clinical trial end point that is associated with measures important to patient care.