Biological therapies in IBD: an international course

Crohn's disease and ulcerative colitis, both chronic inflammatory bowel diseases, have become an important health problem in the US and in Northern Europe. Both diseases require significant medical therapy for treatment and prevention of relapses. Traditional treatment is based on aminosalicylates and steroids. Steroids are associated with major complications and many patients are either dependent upon or refractory to steroids. The development of new drugs is therefore very important. This is possible because of a better knowledge of the pathogenetic mechanisms of the diseases. Many of the new drugs belong to the family of biologic therapies. Because of the expense of production and the parenteral delivery systems needed for most of them, these therapies must prove to be significantly more effective than traditional drugs. Many biologic agents are still under investigation. Therapeutic strategies directed against tumor necrosis factor (TNF)-alpha, including monoclonal antibodies, such as infliximab and CDP-571 and the human recombinant TNF receptor fusion protein, etanercept, have already been proven to be beneficial, especially in treating Crohn's disease. Treatment with infliximab induces even endoscopic and histologic healing. The benefit of additional immunosuppressive therapy is under investigation. New treatment strategies that might change the natural course of the disease can be considered for Crohn's disease. The experience with biologic agents for ulcerative colitis is still limited. A preliminary study with antegren, a recombinant humanized antibody against integrins is promising. The initial safety experience with infliximab is favorable but, ultimately, evaluation of large populations of patients over many years is required to define the relative safety of biologic agents.