After 28 days of intragastric administration, we found that both KW2449 and MTX showed obvious therapeutic effects on CIA rats, not only improving the severity of joint swelling and reducing the arthritis score (Figures 1A, B) but also reducing the release of inflammatory cytokines in the plasma of CIA rats, such as interleukin-17A (IL-17A), interleukin-1α (IL-1α), interleukin-2 (IL-2) and interleukin-6 (IL-6) (p<0.05; p<0.01) (Figure 1E). Here, IL17A is linked to arthritic joint disease.