Emerging therapies for the treatment of spondyloarthritides with focus on axial spondyloarthritis

INTRODUCTION: Spondyloarthritides (SpA) such as axial spondyloarthritis (axSpA) including ankylosing spondylitis (AS) and psoriatic arthritis (PsA) including psoriasis are chronic immune-mediated disorders with involvement of tumor necrosis factor (TNF), interleukin (IL)-17 cytokines, and janus kinases (JAK) in their pathogenesis, with IL-23 clearly also playing a role in psoriasis, PsA, and chronic inflammatory bowel diseases. AREAS COVERED: In this narrative review, we focus on a biologic disease modifying anti-rheumatic drug (bDMARD), the bispecific IL-17A and IL-17 F inhibitor bimekizumab, and a targeted synthetic (ts) DMARD, the JAK inhibitor (i) filgotinib - emerging agents for the treatment of axSpA. Upadacitinib, another JAKi that has recently been reviewed intensively by us is already approved for axSpA and PsA in Europe. EXPERT OPINION: In contrast to inhibition of IL-17, JAKi also work in rheumatoid arthritis (RA), while agents inhibiting IL-17 are not, even though some effect may be there. Indeed, 4 JAKi including filgotinib are approved for RA. There are several head-to-head trials with bimekizumab in plaque psoriasis. The last one showed that the bispecific inhibition of IL-17A and IL-17 F with bimekizumab may indeed be superior to inhibition of IL-17A alone with 300 mg secukinumab (usual dosage). Whether this is also the case for treatment of axSpA and PsA remains to be shown.