AstraZeneca’s SAPHNELO (anifrolumab-fnia) has been approved in the US for the treatment of adult patients with moderate to severe systemic lupus erythematosus (SLE) who are receiving standard therapy. The approval by the Food and Drug Administration (FDA) was based on efficacy and safety data from the SAPHNELO clinical development program, including two TULIP Phase III trials and the MUSE Phase II trial. In these trials, more patients treated with SAPHNELO experienced a reduction in overall disease activity across organ systems, including skin and joints, and achieved sustained reduction in oral corticosteroid (OCS) use compared to placebo, with both groups receiving standard therapy. This marks the first regulatory approval for a type I interferon (type I IFN) receptor antagonist and the only new treatment approved for SLE in more than 10 years. Type I IFN plays a central role in the pathophysiology of lupus and increased type I IFN signaling is associated with increased disease activity and severity. The adverse reactions that occurred more frequently in patients who received SAPHNELO in the three clinical trials included nasopharyngitis, upper respiratory tract infection, bronchitis, infusion-related reactions, herpes zoster and cough. SLE, the most common form of lupus affecting up to 300,000 people in the US, disproportionately affects the African-American, Hispanic and Asian populations. It is a complex autoimmune condition that can affect any organ, and people often experience debilitating symptoms, long-term organ damage and poor health-related quality of life.