Predicting response to Anti-TNF Agents for the treatment of crohn's disease.

The arrival of anti-tumor necrosis factor (TNF) agents has led to a dramatic improvement in the care of patients with Crohn's disease. Since these medications do not work in everyone, and are associated with rare, but serious side effects, we want to selectively treat patients who have the highest chance of responding. A number of variables have been studied to determine their association with response to anti-TNF agents. Clinical parameters include patient characteristics, smoking status and disease phenotype, and biologic markers include C-reactive protein, serum TNF levels and immune responses to microbial antigens. More recently, research has focused on genetics to identify polymorphisms associated with treatment response. Results from individual studies of these factors have not yet allowed for solid clinical applicability. However, further work in this area along with multivariate clinical prediction modeling may soon allow us to deliver 'personalized medicine' by predicting individualized treatment response in patients with Crohn's disease.