The American Gastroenterological Association recommends that, in general, biologic drugs should not be used as first-line treatment for most patients with Crohn's disease. However, some patients with moderate-to-severe disease -- especially those who have not responded to corticosteroids or who suffer from fistulas -- may benefit from initial treatment with infliximab or other biologic drugs. In all cases, the benefits of biologic drugs need to be weighed against their potential risks, which can include increased risk for infections, lymphoma, and drug-related side effects.
Tumor necrosis factor (TNF) blockers, which include infliximab, adalimumab, and certolizumab, can increase the risk for cancer, particularly lymphomas, in children and adolescents. They can also increase the risk for leukemia in patients of all ages.
Some patients who take anti-TNF drugs develop psoriasis. Fungal infections and tuberculosis are also serious concerns for patients who take anti-TNF drugs. Doctors should carefully monitor patients on anti-TNF therapy for any signs of infection. Symptoms of fungal infections include fever, malaise, weight loss, sweating, cough, and shortness of breath.
Infliximab. Infliximab (Remicade) is an anti-TNF drug that was the first biologic drug approved for treating adults and children with Crohn's disease.
Infliximab is used to help control symptoms and to induce and keep the disease in remission. Infliximab is also used to reduce the number of fistulas and maintain fistula closure. Common side effects of infliximab include respiratory infections (sinus infections and sore throat), headache, rash, cough, and stomach pain. Like all anti-TNF drugs, inflixmab can potentially cause serious severe side effects, including increased susceptibility to viral, fungal, and bacterial infections (including tuberculosis). Other severe side effects may include lymphoma (a type of cancer), heart failure, liver failure aplastic anemia, nervous system disorders, and allergic reactions.
Adalimumab. Adalimumab (Humira) is a biologic drug used for inducing and achieving remission in adult patients with moderate-to-severe Crohn's disease. Like infliximab, adalimumab blocks TNF. Also approved for treating symptoms of rheumatoid arthritis, adalimumab requires injections to initiate treatment, followed by a maintenance shot every other week.
In addition to pain at the injection site, common side effects of adalumimab include upper respiratory infections, headache, rash, and nausea. Adalimumab’s potential severe side effects are similar to those of infliximab. In addition, adalimumab may reactivate hepatitis B in patients who carry the virus in their blood.
Certolizumab. Certolizumab (Cimzia) is another anti-TNF drug given by injection. Patients receive an injection every 2 weeks for the first 3 weeks. Once patients show signs of improvement, they receive an injection once a month. Certolizumab’s side effects are similar to those of adalimumab and infliximab.
Natalizumab. Natalizumab (Tysabri) is also a biologic drug, but it does not target TNF. Instead, natalizumab affects white blood cells involved in the inflammatory response. Natalizumab is given by intravenous infusion once a month in a doctor’s office or hospital infusion clinic.
Review Date: 09/28/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.