IFNA1 and systemic lupus erythematosus: In a Phase IIb trial enrolling 431 moderate to severe active SLE patients with inadequate responses to standard-of-care treatments, sifalimumab, a fully humanized anti-IFN-α IgG1κ monoclonal antibody, was effective in meeting the primary endpoint in determining the percentage of patients achieving an SLE responder index (SRI) response at week 52 (86).