Step-down to anti-TNF monotherapy (IFX) for 6 months after 6 months of combination therapy in 84 of 99 children (mean age 14.5 ± 2.5 years) with moderate to severe Crohn's disease (including fistulizing disease) who responded to the initial 12-week induction with combination therapy showed no significant difference in outcomes at 12 months. This evidence concerns the gene TNF and Crohn disease.