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

Abstract

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.

Figure 1

Changes in A, Short Form 36 (SF‐36) physical component summary (PCS) and mental component summary (MCS) scores and B, Functional Assessment of Chronic Illness Therapy (FACIT)–Fatigue scores between baseline and year 6. The timing of baseline assessments differed across the population, according to parent trial treatment. Broken lines represent the minimum clinically important difference 27, 30. Values beneath each pair of columns represent the number of patients assessed at that time point.

Figure 2

Short Form 36 domain scores at study years 1, 3, and 6. PF = physical functioning; RP = role physical; BP = bodily pain; GH = general health; VT = vitality; SF = social functioning; RE = role emotional; MH = mental heath; AG = age‐ and sex‐matched. MCID = minimum clinically important difference.

Figure 3

Adjusted mean changes from baseline over time for A, SF‐36 PCS and MCS scores and B, FACIT–Fatigue scores. The timing of baseline assessments differed across the population, according to parent trial treatment. Broken lines represent the minimum clinically important difference 27, 30. Values were means‐adjusted for baseline SF‐36 MCS and PCS, FACIT–Fatigue, age, disease duration, Safety of Estrogens in Lupus Erythematosus National Assessment Systemic Lupus Erythematosus Disease Activity Index score, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index score, sex, and race. MCID = minimum clinically important difference (see Figure 1 for other definitions). * = P < 0.05; † = P < 0.01 versus placebo.

Figure 4

Adjusted mean changes from baseline over time. Values were means‐adjusted for baseline SF‐36 MCS and PCS, FACIT–Fatigue, age, disease duration, Safety of Estrogens in Lupus Erythematosus National Assessment Systemic Lupus Erythematosus Disease Activity Index (SELENA‐SLEDAI) score, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index score, sex, and race. A and C, SF‐36 PCS and MCS scores. B and D, FACIT–Fatigue scores. In A and B, data were stratified according to responder status. In C and D, data were stratified according to elevated anti–double‐stranded DNA (anti‐dsDNA) and/or low C3/C4 status. Patients with a baseline SELENA‐SLEDAI score of <4 were excluded from the subgroup analysis. The timing of baseline assessments differed across the population, according to parent trial treatment. Broken lines represent the minimum clinically important difference 27, 30. See Figure 1 for other definitions. * = P < 0.05; † = P < 0.01 versus nonresponders (A and B) and versus no elevated anti‐dsDNA and/or low C3/C4 (C and D).