Study participants receive standard therapy (induction and maintenance) for lupus nephritis in addition to receiving either placebo (no active medicine) or belimumab. Induction therapy starts before the first dose of study drug (belimumab or placebo). Maintenance therapy begins after completion of induction therapy and continues for the remainder of the study. Participants receive study drug throughout the entire study, during both induction and maintenance periods. The controlled period of the study is 104 weeks. The random assignment in this study is 1 to 1 which means you have an equal chance of receiving treatment with belimumab or placebo. Participants who successfully complete the 104-week study may enter into a 6-month open-label extension. All participants in the open-label extension receive belimumab.
The purpose of this study is to evaluate the efficacy, safety, and tolerability of belimumab in adult patients with active lupus nephritis.