Progress in the use of type I interferon blockade in systemic lupus erythematosus

INTRODUCTION: The successful clinical trials of the type I interferon (IFN) receptor monoclonal antibody, anifrolumab, have proven the benefit of IFN blockade in systemic lupus erythematosus (SLE), and paved the way for novel therapies targeting this pathway. AREAS COVERED: This review will cover the updated evidence regarding the efficacy and safety of anifrolumab since its positive phase III trial in 2020. In addition, indications of the clinical benefit of emerging IFN-targeting therapies, such as monoclonal antibodies targeting IFN-producing cells and small-molecule inhibitors of IFN signaling, currently in phase II/III clinical trials will be discussed. EXPERT OPINION: Evidence from clinical trials and real-world studies have revealed the potential for IFN blockade to reduce disease activity and flares, improve glucocorticoid (GC) tapering and increase the attainment of treat-to-target goals in SLE, including in refractory patients. The efficacy of IFN blockade across different SLE disease manifestations and patient subgroups remains under investigation, as well as the ability of such treatments to reduce end organ damage. Regardless, it is clear that IFN blockade has earned a place as part of the standard of care in SLE. Future studies are needed to define whether IFN blockade moves toward being a first-line treatment.