Patient demographics and baseline clinical characteristics (safety population; N=142)
| Total (N=142) | |
| Country, n (%) | |
| Japan | 72 (50.7) |
| South Korea | 70 (49.3) |
| Female, n (%) | 129 (90.8) |
| Mean age (SD), years | 34.6 (9.3) |
| Ethnicity, n (%) | |
| Hispanic or Latino | 1 (0.7) |
| Non-Hispanic or non-Latino | 141 (99.3) |
| Mean BMI (SD), kg/m2 | 21.8 (3.4) |
| Mean SLE disease duration (SD), years | 8.7 (6.6) |
| BILAG organ domain involvement*, n (%) | |
| ≥1A or 2B | 64 (45.1) |
| ≥1A | 18 (12.7) |
| ≥1B | 116 (81.7) |
| Neither A nor B | 20 (14.1) |
| BILAG organ system involvement (A or B scores), n (%) | |
| General | 7 (4.9) |
| Mucocutaneous | 77 (54.2) |
| Neurological | 1 (0.7) |
| Musculoskeletal | 40 (28.2) |
| Cardiovascular and respiratory | 1 (0.7) |
| Vasculitis | 22 (15.5) |
| Renal | 28 (19.7) |
| Haematology | 31 (21.8) |
| Mean SELENA-SLEDAI Score (SD) | 9.3 (3.9) |
| SELENA-SLEDAI category, n (%) | |
| ≤9 | 73 (51.4) |
| ≥10 | 69 (48.6) |
| SELENA-SLEDAI Flare Index*†, n (%) | |
| ≥1 flare | 27 (19.0) |
| ≥1 severe flare | 4 (2.8) |
| Mean PGA (SD) | 1.2 (0.6) |
| SDI Score | |
| Mean (SD) | 0.5 (0.8) |
| Median (min, max) | 0.0 (0, 4) |
| ANA‡ | |
| Positive (≥0.80 index or ≥80 titre), n (%) | 140 (98.6) |
| Anti-dsDNA | |
| Positive (≥30 IU/mL), n (%) | 118 (83.1) |
| Complement level, n (%) | |
| Low C3 (<90 mg/dL) and/or low C4 (<10 mg/dL) | 121 (85.2) |
| No low C3 or C4 | 21 (14.8) |
| Mean proteinuria level (SD), g/24 hours | 0.7 (1.0) |
| Proteinuria category (g/24 hours), n (%) | |
| ≤0.5 | 95 (66.9) |
| >0.5 | 47 (33.1) |
| >0.5 to <1 | 13 (9.2) |
| 1 to <2 | 19 (13.4) |
| ≥2 | 15 (10.6) |
| Medication at baseline | |
| Corticosteroids, n (%) | 140 (98.6) |
| Mean daily prednisone§ dose (SD), mg/day | 10.1 (5.9)¶ |
| Median daily prednisone§ dose (IQR), mg/day | 10.0 (6.3, 12.5)¶ |
| Antimalarials**, n (%) | 58 (40.8) |
| Hydroxychloroquine | 32 (22.5) |
| Hydroxychloroquine sulfate | 27 (19.0) |
| Immunosuppressants/immunomodulatory agents, n (%) | 108 (76.1) |
| Azathioprine | 17 (12.0) |
| Ciclosporin | 14 (9.9) |
| Leflunomide | 1 (0.7) |
| Methotrexate | 22 (15.5) |
| Mizoribine | 17 (12.0) |
| Mycophenolate mofetil | 25 (17.6) |
| Pimecrolimus | 2 (1.4) |
| Tacrolimus | 38 (26.8) |
| Aspirin, n (%) | 17 (12.0) |
| NSAIDs, n (%) | 47 (33.1) |
Baseline was defined as the last available value prior to belimumab initiation: Day 1 of the parent study for patients randomised to belimumab and Week 52 of the parent study for patients randomised to placebo.
*Patients may have been counted in more than one category.
†SLE flares reported between the last SLE flare assessment and ‘baseline’.
‡ANA units were ‘index’ for patients from BEL113750 and ‘titre’ for patients from BEL112341.
§Or prednisone equivalent.
¶Two patients did not receive corticosteroids at baseline and therefore were counted as zero dose.
**One patient was counted in both hydroxychloroquine (with the start date of 2003 but no end date) and hydroxychloroquine sulfate (with the start date of 2013 and end date of 2016) categories and therefore, the two individual antimalarial categories include one extra patient compared with the overall antimalarials group.
ANA, antinuclear antibodies; BILAG, British Isles Lupus Assessment Group; BMI, body mass index; dsDNA, double-stranded DNA; NSAIDs, non-steroidal anti-inflammatory drugs; PGA, Physician Global Assessment; SD, standard deviation; SDI, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index; SELENA-SLEDAI, Safety of Estrogens in Lupus Erythematosus National Assessment-SLE Disease Activity Index; SLE, systemic lupus erythematosus.