Crohn's disease (CD) is a chronic disease with a heterogeneous clinical presentation, relapse rate and treatment response. Insufficient control of mucosal inflammation results in irreversible bowel damage and complications and at present no markers are available to predict such a complicated disease course at diagnosis. Therefore, to prevent overtreatment of low risk patients, step-up treatment with subsequent introduction of corticosteroids, thiopurines maintenance and TNF-blockers if a previous category fails is standard care. Combination treatment with thiopurines and a TNF-blocker is more effective than monotherapy but associated with a higher risk for infectious complications. Landmark studies convincingly showed an improved long-term outcome if the TNF-blocker infliximab is introduced early after diagnosis. The standard step-care approach thus prolongs steroid exposure and delays start of disease modifying biologicals in high risks patients. Given the higher efficacy of combination therapy with a thiopurine of infliximab and potential allergic reactions and lower response rates after re-initiation of this chimeric biological, temporary monotherapy with this TNF-blocker has not been studied as first line treatment before. Adalimumab is a humanised monoclonal antibody and subsequently, combination therapy of adalimumab + thiopurines has only a marginal effect on anti-drug anti-body formation. Furthermore, combination therapy with adalimumab does not enhance the clinical response. Therefore, periodic treatment with adalimumab in combination with close monitoring after drug-discontinuation, in newly diagnosed CD might improve outcome, reduce drug-related side effects while still preventing overtreatment. The aim of this study is to compare the long-term efficacy and safety of periodic adalimumab as initial treatment in newly diagnosed CD patients compared to standard step-care with corticosteroid/budesonide as the initial treatment