Will pharmacogenetics predict response to therapies in rheumatoid arthritis?

Rheumatoid arthritis (RA) is a systemic inflammatory disorder that mainly affects the joints. When left untreated, the disease can be aggressive resulting in irreversible joint damage with high morbidity and mortality. Disease modifying anti-rheumatic drugs (DMARDS) are the cornerstones of treatment in RA. In recent times, a new class of disease-modifying medications, the biologics, has been added to the therapeutic armamentarium in RA. DMARDs not only ameliorate the clinical signs and symptoms of disease, but also prevent the radiographic progression of joint damage. However, there is significant variability in patients' response to these agents, both in terms of efficacy and toxicity. At the present time, there are no reliable means of predicting, a priori, an individual patient's response to a given DMARD. In this review, the current published literature on the pharmacogenetics of traditional DMARDS and the newer biological DMARDs is highlighted. Pharmacogenetics may be a powerful tool for optimizing drug therapy in patients with rheumatoid arthritis.