Steroid-sparing effect of belimumab: results from a retrospective observational study of real-world data

Objective: Comparison of oral corticosteroid (OCS) use in patients with SLE in a US rheumatology network pre- and post-belimumab initiation.

Methods: This retrospective cohort study (GSK Study 214140) used data from the Patient-Important Outcomes Data Repository (PIONEER)-Rheumatology database. Eligible adults with SLE initiated belimumab between 1 January 2012 and 30 June 2021, and had available data for >180 days pre- and >360 days post-belimumab initiation. The index was the date of belimumab initiation. Changes in OCS use were measured by: proportion of patients receiving OCS; mean total OCS dose/patient; mean total number of OCS days supplied/patient; mean daily OCS dose for days supplied/patient; the proportion of patients with OCS doses of ≤5 mg/day and ≤7.5 mg/day for days supplied. These changes were assessed between period (P)1 (6 months pre-index) and P2 (first 6 months post-index) and P3 (second 6 months post-index) in patients with OCS use in P1 who persisted with belimumab at each assessed period.

Results: Overall, 608 patients received belimumab for 180 days (full analysis set (FAS)) and 492 for 360 days. Most patients were female (92.8%); 70.4% had moderate SLE. In P1, 56.3% of FAS patients and 54.5% of patients who persisted with belimumab for 360 days received OCS.Among patients receiving OCS in P1, significantly fewer patients received OCS in P2 (78.4%) and P3 (64.9%) vs P1 (100.0%). Significant reductions from P1 were observed in P2 and P3 in the mean total OCS dose/patient, the mean OCS daily dose for days supplied and the proportions of patients with OCS dose of ≤5 mg/day and ≤7.5 mg/day, and the mean total OCS days supplied/patient in P3 only.

Conclusions: This analysis showed significant reductions in OCS dose and use in patients with SLE who persisted with belimumab, providing more real-world evidence for belimumab's steroid-sparing effect.