JAK2 and systemic lupus erythematosus: Similarly, the treatment of patients with SLE with tofacitinib (which inhibits JAK3, as well as JAK1 and JAK2 to a lesser extent) decreased the IFNGS expression in a phase one trial [117], and multiple JAKis were shown to suppress the IFNGS in a study of off-label use in pediatric patients with SLE [118].