Response to: 'Regulatory role of the JAK STAT kinase signalling system on the IL-23/IL-17 cytokine axis in psoriatic arthritis by Raychaudhuri et al

In their correspondence, Raychaudhuri et al1 describe an alternative mechanism for the role of Janus Kinase and Signal Transducer and Activator of Transcription (JAK/STAT) signalling in the pathogenesis of psoriatic arthritis (PsA). The interleukin (IL)-23/IL-17 cytokine axis is a well-documented and prominent pathway in the understanding of the pathogenesis of PsA, indicated by the approval of the monoclonal antibody (mAb) ustekinumab, a fully human Ig G1k mAb against the common subunit p40 of IL-12 and IL-23, for the treatment of psoriasis and PsA by the European Medicines Agency and Food and Drug Administration.2 In addition, IL-17 itself is also a direct therapeutic target for the treatment of PsA and psoriasis, with IL-17A mAb secukinumab now approved also for PsA and psoriasis.3 4 We agree that the tofacitinib may function by inhibiting JAK2/STAT3, leading to an inhibition of the functional effects of...