These research efforts were vital in directing the attention of the pharmaceutical industry to initial anti-TNF approaches, which eventually resulted in clinical trials that were successfully performed for a variety of chronic inflammatory diseases, including rheumatoid arthritis (Elliott et al., 1993), psoriasis, psoriatic arthritis, Crohn’s disease, juvenile idiopathic arthritis, spondyloarthritis, and Behçet’s disease (Sfikakis, 2010). This evidence concerns the gene TNF and psoriatic arthritis.