These models were used to deepen the understanding of the MoA of different therapeutic strategies, such as biological drugs that target the IL-1 pathway (anakinra and canakinumab) or the IL-6 pathway (tocilizumab and sarilumab, the latter not indicated for Still’s disease yet but being investigated in a phase II clinical trial, NCT02776735) and non-biological drugs (corticosteroids, i.e., prednisone, and methotrexate). This evidence concerns the gene IL1A and systemic-onset juvenile idiopathic arthritis.