Background/Purpose: Effectiveness of belimumab in black/African American (AA) patients (pts) with Systemic Lupus Erythematous (SLE) is yet to be adequately demonstrated. The objective of this analysis is to describe the clinical outcomes associated with belimumab therapy in black/AA SLE pts in community practice settings in the United States (U.S).

Methods: This is a multi-center cohort study adult SLE pts in the U.S recruited by a nationally representative random sample of rheumatologists who were treating >10 SLE pts annually and had >5 yrs of practice experience. Physicians are randomly identifying SLE pts in their practices who had received at least 8 infusions of belimumab as part of usual care and assessed the following data corresponding to the 6 months prior to belimumab initiation (baseline: BL) and the first 6 months after belimumab initiation: demographics, comorbidities, SLE disease characteristics, clinical outcomes and resource utilization (including medications). The percentage change in disease manifestations was assessed in pts based on physician judgment at 6 months post belimumab initiation in comparison to baseline. Black/AA pts were included in this interim subset analysis.

Results: Analysis included 58 black/AA SLE pts (from 31 rheumatologists from 18 states) with available data; mean pt age was 40.3 years; 93% female; and 50% diagnosed with SLE for ≥ 5 yrs. At BL, 76% had high anti-dsDNA, 59% had low C3 or C4; and 2%, 71% and 28% had mild, moderate and severe disease respectively. The top 3 reasons for initiating belimumab (10mg/kg) were ineffective previous treatment regimens, decrease the use of steroids (steroid sparing) and worsening patient condition; 83%, 69% and 67% of pts concomitantly used oral steroids, antimalarials and immunosuppressants respectively. After 6 months of belimumab therapy, 90%, 41% and 14% of pts had an overall clinical improvement of ≥20%, ≥50%, and ≥80% respectively. Changes in manifestations by organ system (top-5) are shown in the table. The mean reduction in steroid dose was 14.2 mg/day; 10% discontinued steroids and among those still taking steroids, 93% decreased their doses.

Conclusion: In this analysis of black/AA pts receiving at least 6 months of belimumab therapy in clinical practices, clinical improvements were observed in a majority of pts with SLE across multiple manifestations. Steroid sparing effects were observed in most of the pts. Additional studies assessing belimumab effectiveness in black/AA pts with SLE are warranted.