A Phase 2, Multicenter, Open-label, Dose-escalation Study to Evaluate the Safetyand Tolerability of Intravenous Dose of MEDI-546, a Human Monoclonal Antibody Directed Against Type I Interferon Receptor (IFNAR), in Japanese Subjects With Active Systemic Lupus Erythematosus (SLE)

INTERVENTION: Intervention name : MEDI‐546 Dosage And administration of the intervention : Stage I: 100 mg IV, single dose and multiple doses once every 4 wks for 48 wks Stage II: 300 mg IV, multiple doses once every 4 wks for 156 wks Intervention name : MEDI‐546 Dosage And administration of the intervention : Stage I: 300 mg IV, single dose and multiple doses once every 4 wks for 48 wks Stage II: 300 mg IV, multiple doses once every 4 wks for 156 wks Intervention name : MEDI‐546 Dosage And administration of the intervention : Stage I: 1000 mg IV, single dose and multiple doses once every 4 wks for 48 wks Stage II: 1000 mg IV, multiple doses once every 4 wks for 156 wks, the dose at Stage II was changed to 300 mg IV. CONDITION: Systemic Lupus Erythematosus INCLUSION CRITERIA: ‐ Fulfils at least 4 of the 11 American College of Rheumatology (ACR) classification criteria for SLE. ‐ Weight greater than or equal to 40.0 kg. ‐ Diagnosis of pediatric or adult SLE with chronic disease activity requiring ongoing treatment or observation for 24 weeks or more prior to screening. ‐ Currently receiving stable dose of oral prednisone and/or antimalarials/immunosuppressives. ‐ Active moderate to severe SLE disease based on SLE disease activity score.