The advent of IL-17A blockade in ankylosing spondylitis: secukinumab, ixekizumab and beyond.

INTRODUCTION: Secukinumab, an interleukin-17A (IL-17A) antagonist, is the first non-TNF alpha inhibitor agent licensed for ankylosing spondylitis (AS), which opens up a new era of alternative cytokine targets beyond TNF. Areas covered: This review explores the pathophysiology and scientific evidence behind the use of this new mode of action and discusses the basis for its efficacy and clinical utility in the management of AS. In particular, how the emergent data points towards the efficacy of secukinumab and ixekizumab, a second emergent IL-17A blocker, in AS has helped focus research into the IL-23/17 axis in entheseal driven disease in man and how IL-17A inhibition may be linked to the presence of innate and adaptive immune cell populations capable of IL-17A elaboration in these target tissues. Expert commentary: Collectively these emergent data point towards an efficacious role of IL-17A inhibition strategies targeting AS pathogenesis in a fundamental way whilst carrying a good safety profile.