Anifrolumab, previously known as MEDI-546, is the first biologic targeting the IFN system to be approved for SLE.42,44 It is a fully human, IgG1κ monoclonal antibody, able to bind to IFN-α/β receptor (IFNAR), leading to prevention of signal transmission by all type I IFNs.42,44 Recent phase II and III trials have proved its efficacy and safety in active SLE,41–45 summarised in Table 1. Here, IFNAR1 is linked to systemic lupus erythematosus.