Introduction: Adalimumab is a recombinant fully-human monoclonal immunoglobulin (IgG1) antibody utilized in the treatment of Crohn's disease. Unfortunately no clinical or genetic markers exist to predict response to anti-tumor necrosis factor-alpha (TNF) therapy. The aim of this study was to evaluate the association between selected genes involved in cytokine regulation and response to adalimumab treatment in Crohn's disease.
Methods: twenty-four patients with Crohn's disease either naïve (n = 8) or had lost response or were unable to tolerate the chimeric anti-TNF antibody infliximab (n=16) were enrolled in the study. Patients were genotyped for main polymorphisms in NOD2, CD14 and TLR4 genes. Response to adalimumab treatment was defined as a decrease of Crohn's disease activity index of at least 100 points or a closure of at least 50% of fistulas in case of fistulizing Crohn's disease.
Results: overall, 75% of patients did respond to treatment. However, no statistically significant association was found between any of the genotypes and the response to adalimumab.
Conclusions: In our small study group no association between the studied polymorphisms and response to adalimumab was apparent. Systematic studies to search for genetic markers of response to anti-TNF therapy are necessary.