Biologic therapies in clinical development for the treatment of rheumatoid arthritis.

The therapeutic objective in patients with rheumatoid arthritis (RA) is reduction of disease activity with an ultimate goal of disease remission. Limitations of currently available disease-modifying antirheumatic drugs and biologic therapies suggest that there remains an unmet need for agents that advance these goals in a greater proportion of patients. Progress in our understanding of the regulatory molecules and pathways that mediate the immune and inflammatory responses necessary for the initiation and perpetuation of RA has led to the identification of new targets for therapy. It is expected that the therapeutic modulation of these targets, which include proinflammatory cytokines, T and B cells, adhesion molecules, chemokines, and intra- and extracellular signaling pathways, can provide new treatment strategies in patients with RA and other autoimmune disorders. Toward this end, a series of novel agents with diverse mechanisms of action are in development. Although many of these agents are still beyond the clinical horizon, several of them have shown promise in recent trials. This article reviews a few of the many treatment strategies currently being evaluated, which are hoped to lead to greater benefits and better disease management in the clinical setting.