Efficacy and Safety of Subcutaneous Belimumab in Anti–Double-Stranded DNA–Positive, Hypocomplementemic Patients With Systemic Lupus Erythematosus

Objective: To investigate the efficacy and safety of belimumab, a human immunoglobulin monoclonal antibody against B lymphocyte stimulator, in a subset of patients with systemic lupus erythematosus (SLE) who were hypocomplementemic (C3 <90 mg/dl and/or C4 <10 mg/dl) and anti–double-stranded DNA (anti-dsDNA) positive (≥30 IU/ml) at baseline. Methods: In this phase III, double-blind, placebo-controlled study (BEL112341; ClinicalTrials.gov identifier: NCT01484496), patients with moderate to severe SLE (Safety of Estrogens in Lupus Erythematosus National Assessment version of the Systemic Lupus Erythematosus Disease Activity Index [SELENA–SLEDAI] score ≥8) were randomized (2:1) to receive weekl…