IL17A and ankylosing spondylitis: Considering the clinical and pathobiological link between psoriasis and spondyloarthritis and the efficacy of IL-17 blockade in both conditions, a randomized, placebo-controlled phase II clinical trial assessed the safety and efficacy of the anti-p19 antibody risankizumab in ankylosing spondylitis, the prototypical subform of AxSpA (13).