Biological Therapy For Inflammatory Bowel Disease - Side Effects and Concerns

Side Effects and Concerns

There have been concerns about the side effects of monoclonal antibodies, and specifically of infliximab, but these are rare. Early side effects include the risk of allergic reactions (including anaphylaxis which may be life-threatening), and reactions to the infusion. These are often treated with medications given before treatment. Infliximab also carries a risk of worsening infection, and can cause reactivation of old infections, like tuberculosis. Over time, there is the risk of serum sickness, which is a delayed hypersensitivity response to the medication. Later complications may include multiple sclerosis and lymphoma. Finally, the medication is quite expensive, with treatment costs ranging from US$3000 to $8000 per infusion.

Loss of response to infliximab over time is a concern, due to the development of antibodies to infliximab (termed human anti-chimeric antibodies, or HACA). This can be reduced by concurrent treatment with other immunosuppressant medications (including azathioprine and methotrexate), by maintaining a regular infusion schedule, and by giving patients a pre-treatment dose of steroid medication.