IL1B and macrophage activation syndrome: However, despite early initiation of anakinra, we observed an incidence of MAS of 18% in the first two years after diagnosis (in 11 of 12 patients while still using IL‐1–targeted therapy), which is in line with (and not lower than) the percentages reported in patients treated with glucocorticoids and/or DMARDs for sJIA‐SD.17, 20, 27, 31, 32