Study project Screening (Days -14 do 0): Laboratory and endoscopic (up to three months before Day 0) results will be obtained to check with inclusion/exclusion criteria.~Part A (Days 1 to 71): Induction therapy with 3 doses of infliximab 5 mg/kg will be applied on days 1 - 15 - 43. Simultaneously in patients receiving steroids, steroid tapering will be performed up to 71 Day. At Day 71 clinical (PCDAI) and endoscopic assessment will be done. Patients with no clinical response will be qualified to Follow-up surveillance group. Patients with clinical response present will be randomized to two groups of maintenance therapy:~1. Infliximab with immunomodulation 2. Infliximab alone~Part B (Weeks 10 - 54): Patient with both groups will have scheduled visits at Weeks 14, 22, 30, 38, 46. Infliximab infusions and laboratory tests will be performed at each visit. At Week 54 clinical (PCDAI) and endoscopic assessment will be done.~Follow Up: 4 weeks after last visit - SAE monitoring Aim of the study~The aim of the study is confirmation of efficacy of induction therapy with three doses of infliximab In patients with Crohn disease aged 7-17 years, and comparison of efficacy and safety of two regiment of maintenance therapy:~Infliximab with immunomodulation~Infliximab alone Drug dosing in therapy regimens.~Infliximab: 5 mg/kg mc In intravenous infusion lasting over 2 hrs. Azathioprine: 1,5 - 3 mg/kg/24h Methotrexate: 10 - 25 mg/week~Safety assessment~AE and SAE monitoring will be conducted during whole period of the study~Efficacy assessment~Primary endpoint~Part A:~• Clinical response defined as: Decrease of PCDAI ≥ 15 points AND PCDAI less than 30 points~• Remission defined as: PCDAI ≤ 10 points~Part B:~Loss of clinical response defined as:~Increase of PCDAI more than 15 points OR PCDAI > 30 points~Secondary endpoints~Part A:~• Time to steroid cessation~Part B:~• Necessity to increase/change maintenance therapy with~o Surgery~o Increase of infliximab dose~Increase of immunomodulator dose~Steroids induction~Statistical methods~ITT analysis~Primary endpoints: chi2 tests, Kaplan-Meier analysis~Secondary endpoints: chi2 tests, Kaplan-Meier analysis, U Mann-Whitney analysis
The aim of the study is confirmation of efficacy of induction therapy with three doses of infliximab In patients with Crohn disease aged 7-17 years, and comparison of efficacy and safety of two regiment of maintenance therapy:~Infliximab with immunomodulation~Infliximab alone