A Study of Belimumab, a Fully Human Monoclonal Anit-BLyS Antibody, in Subjects With Systemic Lupus Erythematosus (SLE)

This is a Phase 3, multi-center, randomized, double-blind, placebo-controlled, 52-week study to evaluate the efficacy and safety of belimumab in subjects with active SLE. In addition to stable standard therapy, subjects will be randomized to 1 of 3 treatment groups in a 1:1:1 ratio: 1 mg/kg belimumab, 10 mg/kg belimumab or placebo. At randomization, subjects will be stratified by their screening SELENA SLEDAI score (6-9 vs >= 10), screening proteinuria level (< 2 g/24 hour vs >= 2 g/24 hour equivalent) and race (African descent or indigenous-American descent vs other). Subjects will be dosed with study agent on Days 0, 14, and 28, then every 28 days through 48 weeks, with a final evaluation at Week 52 (4 weeks after the last dose). Study agent will be administered intravenously over 1 hour. Approximately 810 SLE subjects will be randomized at approximately 150 sites, with a target of about 270 subjects per treatment group. All subjects will continue the stable standard therapy they were receiving during the screening period. All subjects, including withdrawals, will return for an Exit (final evaluation) visit approximately 4 weeks after their last dose of study agent. Subjects who withdraw or do not enter the continuation protocol after 48 weeks of treatment will be required to return for an additional follow-up visit approximately 8 weeks after their last dose of study agent.