Secukinumab is monoclonal antibody that targets interleukin 17 (IL-17) for treatment of psoriatic arthritis, psoriasis, and ankylosing spondylitis. We herein present a psoriatic arthritis patient who developed leukocytoclastic vasculitis (LCV) following treatment with secukinumab. Genetic studies identified amino acid changes in two different IL-17 receptors, IL-17RA and IL-17-RC, and interacting DOCK8, Rab27A, and STX1 proteins. LCV completely resolved after withdrawal of the drug, transient treatment with dapsone and methylprednisolone, and switching to long-term therapy to IL-23 inhibitor tildrakizumab. This case reveals potential molecular bases of disease pathogenesis, intolerance of IL-17 blockade, and responsiveness to IL-23 inhibition in psoriatic arthritis.
Keywords: Antirheumatic Agents; Biological Therapy; Psoriatic Arthritis.