Introduction: Adaptive immunity in intestinal inflammation may play a key role in the pathogenesis of Crohn's disease. In particular, interleukin (IL)-23 may be a key mediator in chronic intestinal inflammation by inducing the differentiation of naive CD4+T cells into Th17, with the production of several pro-inflammatory cytokines. Furthermore, IL-23 induces interferon- (IFN- ) production from activated T cells, a critical cytokine in innate and adaptive immunity against infections.Areas covered: We aim to review the available data from literature regarding the role of IL-23, with a more specific focus on the recent progresses in the therapeutic modulation of this cytokine.Expert commentary: Increased knowledge regarding the role of IL-23 has allowed for the development of effective therapeutic progresses by blocking the IL-23 mediated pathways. Primary or secondary loss of response to anti-TNF therapies in Crohn's disease patients during the first year is widely described in literature: the development of new drugs, with alternative mechanisms of action, is thus a key point to consider for the optimal management of these subjects. Drugs blocking the IL-12/23 pathway showed a good efficacy and safety profile in immune-mediated diseases Further studies are necessary regarding the role of the single blockade of IL-23.