Long‐Term Impact of Belimumab on Health‐Related Quality of Life and Fatigue in Patients With Systemic Lupus Erythematosus: Six Years of Treatment

OBJECTIVE: To report long‐term health‐related quality of life (HRQoL) and fatigue outcomes in patients with systemic lupus erythematosus (SLE) receiving belimumab. METHODS: Patients with SLE who completed the Study of Belimumab in Subjects with SLE 76‐week trial (BLISS‐76) were enrolled in this continuation study (BEL112233 [ClinicalTrials.gov identifier: NCT00724867]). The belimumab groups continued to receive the same dose (1 mg/kg or 10 mg/kg) intravenously. After March 2011, all patients received belimumab 10 mg/kg every 28 days plus standard therapy. The placebo group switched to belimumab 10 mg/kg. HRQoL and fatigue assessments included the Short Form 36 (SF‐36) health survey and the Functional Assessment of Chronic Illness Therapy (FACIT)–Fatigue subscale. Post hoc subgroup analyses (BEL206350) assessed clinical characteristics associated with improved HRQoL and fatigue. RESULTS: Of the 268 patients enrolled, 140 completed the study. Patients receiving long‐term belimumab treatment reported continued improvements in HRQoL and fatigue. At study year 6, the mean ± SD SF‐36 physical component summary (PCS) score and the mental component summary (MCS) score increased from 37.0 ± 9.9 at baseline to 41.7 ± 10.0 (mean ± SD change 4.8 ± 9.4) and from 44.3 ± 11.3 to 47.0 ± 11.6 (mean ± SD change 2.7 ± 11.3) for the PCS and MCS, respectively, exceeding the minimum clinically important difference (MCID) for improvement (2.5 units). The mean ± SD FACIT–Fatigue score exceeded the MCID of 4 at study years 1–5; at study year 6, the mean ± SD change was 3.7 ± 11.8. Statistically significant associations were observed between parent trial treatment groups and change from baseline in PCS, MCS, and FACIT–Fatigue scores (P < 0.01). CONCLUSION: Long‐term control of SLE disease activity with belimumab plus standard therapy translates into meaningful improvements in patient‐reported fatigue and HRQoL.