Cheng LE, et al. - Researchers conducted this double-blind study to assess the safety and potential effectiveness of AMG 557, a fully human antibody directed against the inducible T-cell costimulator ligand (ICOSL), in subjects having systemic lupus erythematosus (SLE) and active lupus arthritis. At day 169, AMG 557 (vs placebo) demonstrated greater improvements from baseline in global British Isles Lupus Assessment Group (BILAG) index and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores and in tender and swollen joint counts, thereby demonstrating safety and potential efficacy.