Anifrolumab

Anifrolumab, or MEDI-546, is a type 1 interferon receptor (IFNAR) inhibiting IgG1κ monoclonal antibody indicated in the treatment of adults with moderate to severe systemic lupus erythematosus. The standard therapy for systemic lupus erythematosus consists of antimalarials like hydroxychloroquine, glucocorticoids like dexamethasone, and disease modifying antirheumatic drugs like methotrexate. Three monoclonal antibodies (anifrolumab, rontalizumab, and sifalimumab) that target the type 1 interferon pathway entered clinical trials as potential treatments for systemic lupus erythematosus, but so far only anifrolumab has been approved. The design of early clinical trials of anti-interferon treatments such as anifrolumab, rontalizumab, and sifalimumab have come under criticism. The design of the clinical trials use different definitions of autoantibody positivity, making comparison between trials difficult; all trials involve large portions of patients also using corticosteroids, which may alter patient responses in the experimental and placebo groups; and patient populations were largely homogenous, which may have increased the odds of success of the trial. Anifrolumab has also been investigated for the treatment of Scleroderma. Anifrolumab was granted FDA approval on 30 July 2021.