A3AR agonists such as CF101 (IB-MECA) and CF102 (Cl-IB-MECA) have been investigated in several phase II clinical studies including RA, psoriasis, and hepatocellular carcinoma, showing clear evidence of efficacy and an excellent safety profile [17–19], proof of the validity of the A3AR as a therapeutic target. Here, ADORA3 is linked to rheumatoid arthritis.