Infliximab is a genetically engineered substance.
It neutralizes a natural protein in the body called tumor necrosis factor that promotes inflammation. In clinical trials, more than 60 percent of those treated with a single intravenous dose of infliximab experienced improvement in their Crohn's disease after 4 weeks. However, the benefits from the drug decreased during following months. Mayo Clinic doctors say infliximab is an exciting breakthrough for the treatment of Crohn's disease in people who don't respond to other treatments. They add, though, that because the drug is new, its long-term safety is still uncertain.