Daily intraperitoneal administration of the PK2 antagonist PKRA7 to CIA mice before the onset of arthritis from Day 21 resulted in significantly lower arthritis scores in treated mice compared to control CIA mice on Days 28, 31, 33, and 35 (Fig. 5a; P = 0.0104, P = 0.0018, P < 0.001 and P < 0.001, respectively). The gene discussed is PROK2; the disease is arthritic joint disease.