TNF and spondyloarthropathy: Biologic therapies targeting the two main inflammatory pathways involved in the development of axSpA and PsA, the tumor necrosis factor alpha (TNF-α) and the interleukin (IL)-23/IL-17 axes, are the most common choice for spondyloarthritis patients whose disease remains active despite treatment with conventional DMARDs (5, 9, 10, 12).