A phase II study in rheumatoid arthritis and SLE patients using LymphoStat-B, a fully humanised antibody specific for human BAFF (also known as Belimumab), showed modest efficacy in rheumatoid arthritis [64], while a phase II study in SLE patients did not meet the primary efficacy endpoints [65]. This evidence concerns the gene TNFSF13B and systemic lupus erythematosus.