In this RA cohort, serum ACE levels significantly increased both after 6 (257.7 ± 125.0 ng/mL; p = 0.001) and 12 months of tofacitinib therapy (244.9 ± 135.2 ng/mL; p = 0.002) in comparison to baseline (204.2 ± 124.1 ng/mL; Figure 1A). Here, ACE is linked to rheumatoid arthritis.