In regard to future approaches, ABT-122, an immunoglobulin molecule targeting both IL-17A and TNF-α, has recently demonstrated its efficacy in phase I and II trials for RA and psoriatic arthritis50,73; however, given the importance of IL-17 in the pathogenesis of AS, it is expected that trials in patients with AS will commence soon. This evidence concerns the gene IL17A and rheumatoid arthritis.