While such studies have not defined a consistent response across different therapeutics, the concept of monitoring the IFN response as a predictor of therapeutic response is supported by a recent study which measured IFN activity in RA plasma pre- and post- anti-TNF biologic therapy and reported better EULAR outcomes in patients with a high baseline IFNβ/α ratio46. This evidence concerns the gene IFNA1 and rheumatoid arthritis.