IL15 and rheumatoid arthritis: Likewise, although IL‐15 is critical for NK cell maintenance,27 reductions from baseline in NK cell counts do not appear to differ to a meaningful extent for these JAK inhibitors in RA: tofacitinib (−32.5 cells/mm3 at month 1.5, −63.5 cells/mm3 at month 6, +6.5 cells/mm3 at month 22, cross‐sectional analysis in different groups of patients4); baricitinib 4 mg QD (−57.0 cells/mm3 at week 12; −53.4 cells/mm3 at week 2428); upadacitinib 6 mg BID (approximately −50 cells/mm3 at week 1229); sufficient long‐term data are not available for filgotinib.