Several lines of evidence support a pathogenetic role for BAFF and a proliferation-inducing ligand (APRIL) in the pathogenesis of IgA nephropathy and have provided a rationale for therapies that specifically target these cytokines (Table 1).67 Atacicept, a fusion protein that can bind both BAFF and APRIL, was evaluated in a phase 2 trial of 116 proteinuric IgA nephropathy patients. Here, TNFSF13B is linked to IgA glomerulonephritis.