Anifrolumab (brand name Saphnelo) is a monoclonal antibody approved for the treatment of moderate to severe systemic lupus erythematosus (SLE) in patients who are autoantibody-positive and have incomplete response to standard therapy.

It targets the type I interferon receptor, blocking a key inflammatory pathway involved in lupus. Anifrolumab is given as a monthly IV infusion and has been shown to reduce disease activity, flares, and corticosteroid use in clinical trials. It is not approved for lupus nephritis or CNS lupus. Common side effects include respiratory infections and infusion reactions, and it should be used with caution in patients with chronic infections.