Clinical, biological, and endoscopic responses to adalimumab in antitumor necrosis factor-naive Crohn's disease: predictors of efficacy in clinical practice.

Background And Aims: Endoscopic healing and clinical remission are important parameters to evaluate therapeutic efficacy in Crohn's disease. The aim of this study was to investigate the clinical effectiveness of adalimumab in terms of clinical and endoscopic response and to identify predictors of efficacy in clinical practice.

Materials And Methods: A prospective analysis was carried out of 68 antitumor necrosis factor-naive Crohn's disease patients treated with adalimumab for 2 years. Clinical and endoscopic response was assessed using the Harvey-Bradshaw index and the Simple Endoscopic Score for Crohn's disease, respectively.

Results: Adalimumab treatment was associated with clinical remission in 76.6, 90.6, and 87.5% of patients at 6, 12, and 24 months. Loss of efficacy occurred in 17.6% of cases after 24 months of therapy. Clinical remission with normal C-reactive protein at 2 months or with endoscopic response at 6 months was predictive of better outcomes. Mucosal healing rates were 17.2, 44.7, and 39.5% and endoscopic responses were 55.1, 76.6, and 76.3% at the respective time points. Mucosal healing was higher in the early treatment group than in the group with disease of at least 5 years' duration (64.7 vs. 19.1%, P=0.004). Inflammatory phenotype showed a higher percentage of mucosal healing (70%) than stricturing (29.4%) or penetrating (27.3%) disease.

Conclusion: Adalimumab was effective in providing sustained clinical remission. In patients in clinical remission, the C-reactive protein level at 2 months, endoscopic response at 6 months, or inflammatory phenotype and short disease duration could be considered as good predictors of efficacy.