Clinical Trials of Interferon Inhibitors in Systemic Lupus Erythematosus and Preliminary Real-World Efficacy of Anifrolumab.

Approval of anifrolumab for the treatment of moderate-to-severe systemic lupus erythematosus (SLE) in 2021 marked the success of a long quest to target the interferon system, in a disease wherein the latter has long been considered to play a pivotal role. Prior to anifrolumab, a number of agents had been tested in early phase clinical trials in patients with SLE, with equivocal results. Following its approval and marketing in several countries, the first reports regarding efficacy and safety in real-life clinical settings have been published, which suggest remarkable efficacy in skin manifestations of the disease, even after prior failure to multiple immunosuppressive therapies. In this report, we provide a short overview of IFN inhibitors that have been used in clinical trials of SLE, with a focus on anifrolumab; we also review all available evidence to date regarding its real-world efficacy and safety.