Two decades ago, if you had moderate to severe Crohn's, there were few treatment options. In the late 1990s, however, the first in a new class of treatment options emerged for Crohn's disease. Referred to as biologic response modifiers, biologic agents, or simply biologics, these drugs target specific parts of an overactive immune system to reduce inflammation.
Biologics not only relieve Crohn's symptoms but also can bring about remission and keep you in remission. They are indicated for use when someone has moderately to severely active Crohn’s disease and has not responded well to other Crohn’s disease treatments. Many people with Crohn's now live with significantly fewer symptoms, but may worry about side effects. Here's a look at the risks and benefits of biologics.
How Biologics Work
In Crohn's disease, an overactive immune system causes inflammation and damage to the digestive tract. Made from living organisms, biologics work just like substances made by the body’s immune system and can help control the immune system response.
Four biologics are FDA approved for Crohn's. Three of the four block a protein called tumor necrosis factor (TNF) that's involved in inflammation. These drugs are often called anti-TNF drugs or TNF inhibitors. They include Cimzia (certolizumab), Humira (adalimumab), and Remicade (infliximab).
The fourth medication, Tysabri (natalizumab), is called an integrin receptor antagonist. It blocks certain types of white blood cells that are involved in inflammation.
Biologics and Side Effects
Because they suppress the immune system, all biologics carry an increased risk of infections, which in rare cases can be serious. Cimzia, Humira, and Remicade carry a boxed warning for increased risk of serious infections leading to hospitalization or death. If someone taking a biologic develops a serious infection, the drug should be discontinued. People with tuberculosis, heart failure, or multiple sclerosis should not take biologics because they can bring on these conditions or make them worse.
In rare cases, some people taking TNF inhibitors have developed certain cancers such as lymphoma. Lymphoma is a type of cancer that affects the lymph system, which is part of the body’s immune system.
Tysabri increases the risk of a very rare but potentially fatal brain infection called progressive multifocal leukoencephalopathy (PML). Tysabri also can cause allergic reactions and liver damage. Tysabri should not be used at the same time as other treatments that suppress the immune system or TNF inhibitors.
However, most infections that occur with biologic use are far less serious, says Richard Bloomfeld, MD, associate professor of medicine and director of the Inflammatory Bowel Disease Program at Wake Forest University School of Medicine in Winston Salem, N.C. "Infections such as colds, upper respiratory tract infections, and urinary tract infections are common and don't necessarily alter our treatment of Crohn's."
Other common side effects from biologic use include headache, flu-like symptoms, nausea, rash, injection site pain, and infusion reactions.