Real-World Clinical Outcomes in Belimumab-Treated US African American and Hispanic Patients with Systemic Lupus Erythematosus: A Retrospective, Observational Study.

Introduction: This analysis aims to describe real-world clinical outcomes in US African American and Hispanic patients with systemic lupus erythematosus (SLE) receiving belimumab.

Methods: In this post hoc analysis of OBSErve US (GSK Study 117,295) data, patients received intravenous belimumab (10 mg/kg) over 24 months. Outcomes assessed every 6 months after belimumab initiation (index) included: physician-assessed overall clinical response (worse, no improvement, < 20%, 20-49%, 50-79%, ≥ 80% improvement), physician-assessed disease severity (mild, moderate, severe), oral corticosteroid (OCS) use and healthcare resource utilization (HCRU).

Results: Of 501 patients enrolled, 123 and 88 were African American and Hispanic respectively; 69 (56.1%) and 43 (48.8%) were receiving belimumab at 24 months. Of those, 88.4%/95.3% (African American/Hispanic) were female; mean (standard deviation [SD]) age was 41.6 (12.5)/42.2 (10.5) years. Within 6 months post-index, 91.3%/90.7% of patients still receiving belimumab had a ≥ 20% physician-assessed clinical improvement. Among 24 months completers, proportions of patients with severe SLE fell from 34.8%/25.6% at index to 2.9%/4.7% at Month 6 and 2.9%/0% at Month 24. The proportion of patients receiving OCS and mean (SD) daily OCS dose also decreased, from 82.6%/81.4% and 19.7 (12.8)/18.8 (10.0) mg/day at index to 50.7%/34.9% and 3.1 (3.2)/1.6 (2.4) mg/day at Month 24. Fewer patients were hospitalized or required ancillary care services at 18-24 months post-index versus 6 months pre-index.

Conclusion: Belimumab treatment for up to 2 years improved clinical outcomes, disease severity, mean OCS dose and HCRU in US African American and Hispanic patients with SLE, providing real-world evidence for enduring belimumab effectiveness in populations that are markedly impacted by SLE.