Calming Crohn's Disease with New Drug

Background: Crohn's disease is a kind of inflammatory bowel disease (IBD) that affects about a million people in North America. It is thought that overproduction of inflammatory substances called cytokines may cause the chronic intestinal inflammation of Crohn's disease. This has led to the development of agents to block the production of key cytokines. The first was Remicade (infliximab). It blocks a cytokine called tumor necrosis factor alpha.

Summary: A new agent, a monoclonal antibody directed against a cytokine known as interleukin-12 was given subcutaneously (below the skin) for seven weeks to people with Crohn's disease. A good clinical response was found in the group that received the higher dose of the antibody that was tested.

Comment: Although this agent looks good so far, questions remain regarding its long-term safety, especially since cytokines are important in combating infection. The reactivation of tuberculosis in people who received Remicade is an example of the potential for harm due to the suppression of the normal immune response. Other concerns that will need to be addressed include the long-term risk of cancer and, in the long run, the possibility of making Crohn's disease worse.