After the encouraging results of tofacitinib in SLE murine models, its effectiveness has been evaluated in a phase I double-blinded trial including 30 SLE patients.48 Patients were stratified based on the presence of the STAT4 risk allele, which may correlate with increased production of type I IFNs in PBMCs and thus with a more severe phenotype and increased risk of cardiovascular disease in SLE patients. Here, STAT4 is linked to systemic lupus erythematosus.