Figure 2. Overview of small molecule inhibitors targeting the p38 MAPK pathway and JAK/STAT pathway in RA treatment. Each cytokine receptor recruits and activates a specific combination in MAPK and JAK/STAT cascades. Tofacitinib is a pan-JAK inhibitor, selective for JAK3 and JAK1 with minor activity for JAK2 and TYK2. Baricitinib is selective for JAK1 and JAK2 and less selective for JAK3 and TYK2.
