Monoclonal antibodies (mAbs) blocking IL-17A, secukinumab and ixekizumab, are approved for the treatment of psoriasis and secukinumab is also approved for the treatment of psoriatic arthritis and spondyloarthropathies.56 Similarly, drugs targeting the proinflammatory cytokine TNFα (infliximab, etanercept, adalimumab) have been approved for the treatment of multiple human autoimmune diseases including rheumatoid arthritis, Crohn’s disease, and ankylosing spondylitis.57 Here, IL17A is linked to autoimmune disease.