Belimumab (GSK1550188), a recombinant monoclonal antibody targeting soluble BAFF, was the first FDA-approved biologic for SLE treatment, following positive safety and efficacy outcomes in phase III clinical trials (ClinicalTrials.gov Identifier: NCT00424476; ClinicalTrials.gov Identifier: NCT00410384) (251). The gene discussed is TNFSF13B; the disease is systemic lupus erythematosus.