Good safety data were reported concerning 17 children (seven with sJIA and ten with periodic fever syndromes), apart from two serious adverse effects: a VZV infection after a VZV booster in a child on anti-IL-1 (anakinra), low GCs and several csDMARDs and a pneumonia after a MMR booster in a child on anti-IL-1 (canakinumab), low GCs and MTX (49). This evidence concerns the gene IL1B and periodic fever syndrome.