Zhang 2018.

Study characteristics
Methods	Country: international (China, Japan, South Korea) Setting: multicenter Study design: RCT
Participants	705 randomized; all ≥ 18 years belimumab 10 mg/kg (n = 470); age (32.3 ± 9.7 years); M/F (32/419) placebo (n = 235); age (31.7 ± 9.2 years); M/F (16/210) Inclusion criteria Diagnosis of SLE according to ACR classification criteria with a positive antinuclear antibody test result and be receiving a stable SLE medication regimen for at least 30 days prior to enrollment. Exclusion criteria Severe lupus kidney disease or active nephritis requiring acute therapy within 90 days prior to baseline Central nervous system (CNS) lupus requiring therapeutic intervention within 60 days prior to baseline Those requiring new SLE medications other than glucocorticoids within 60 days prior to baseline Those who had received B cell‐targeted therapy
Interventions	10 mg/kg belimumab or placebo by intravenous (IV) infusion in addition to standard of care on days 0, 14, and 28 and then every 28 days through week 48
Outcomes	Efficacy measures 1. SLE responder index (SRI) response rate, including SELENA‐SLEDAI score 2. British Isles Lupus Assessment Group (BILAG) A organ domain score 3. Physician’s global assessment score 4. Physical component summary (PCS) score 5. SLE flare index 6. Decrease in prednisone dose Safety measures: 1. Adverse events (AEs) 2. Serious AEs 3. AEs of special interest 3. Discontinuations due to AEs 4. Deaths
Notes	Withdrawals: belimumab 10mg/kg (n = 82; 17%); placebo (n = 56; 24%) Study funded by GlaxoSmithKline
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomization schedules were created by study sponsor using validated software.
Allocation concealment (selection bias)	Low risk	Staff members preparing belimumab and placebo formulations, which were identical in appearance and labeled in a double‐blind manner, were not involved in other study activities.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Study described as double‐blind.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Staff members preparing belimumab and placebo formulations, which were identical in appearance and labeled in a double‐blind manner, were not involved in other study activities.
Incomplete outcome data (attrition bias) All outcomes	High risk	Proportion of missing outcomes high in both arms (17% in belimumab arm; 24% in placebo arm).
Selective reporting (reporting bias)	Low risk	Includes all expected, prespecified outcomes.
Other bias	Low risk	The study appears to be free of other sources of bias.

ACR: American College of Rheumatology
AE: adverse event
ANA: antinuclear antibodies
anti‐dsDNA: anti‐double‐strandDNA
BILAG: British Isles Lupus Assessment Group
CNS: central nervous system
Ig: immunoglobulin
IV: intravenous
IVIG: intravenous immunoglobulin
M/F: male/female
RCT: randomized controlled trial
SC: subcutaneous
SELENA‐SLEDAI: Safety of Estrogen in Lupus National Assessment (SELENA) ‐ Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)
SLE: systemic lupus erythematosus
TNF: tumor necrosis factor