Considerable advances have been made in understanding the immune system and development of inflammatory diseases during the past two decades. This has led to the development of biologic therapies to address inflammation and long-term health outcomes.
Biologics are proteins that target specific parts of the immune system that cause inflammation. These are medications made from materials found in natural resources, such as human, animal or microorganism. They are produced using biotechnology and other leading-edge technologies.
Biologics differ from conventional medications, because they are complex mixtures. Conventional medications are chemically synthesized and their structure is known. Biologics are harder to manufacture, so they may cost more than other medications you take. Biologics tend to be susceptible to microbial contamination and are heat sensitive.
There are different classes of biologics, each with its unique risks, benefits and inflammatory target. The class of medications used in Inflammatory Bowel Disease (IBD) are tumor necrosis factor α (TNF) inhibitors, integrin receptor antagonists and interleukin inhibitors.
Biologics offer a distinct advantage in the treatment of inflammatory bowel disease, because they target a particular protein that are proven to be involved in inflammation.
Tumor Necrosis Factor α (TNF) Inhibitors
These are the most frequently used biologic type for treatment of IBD. The basis for using these agents is TNF-alpha, a small protein. TNF-alpha has multiple biologic activities that may be directly related to the dysregulation of the immune system and development of IBD. These medications may not work for everyone, and efficacy varies from person to person. It may take up to 8 weeks after starting an anti-TNF to notice improvement in your symptoms.
Examples of these medications include:
- Adalimumab (Humira)
- Infliximab (Remicade)
- Certolizumab Pegol (Cimzia)
- Golimumab (Simponi)
- Etanercept (Enbrel)
Adverse effects of Tumor Necrosis Factor-α (TNF) Inhibitors
Injection site reactions
Common reactions are itching, pain, redness, irritation, bruising or swelling at the medication injection site. These can usually be managed with cold packs and painkillers.
Decrease in the number of white blood cells and infection
The body’s resistance to infection is lowered while taking this medication. Avoid being near people who are sick while taking this class of medications. Wash your hands often. Check with your doctor immediately if you experience fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
Screening for tuberculosis is performed before the initiation of TNF-alpha inhibitor therapy, due to increased risk for latent tuberculosis reactivation.
Heart failure can occur with this class of medications, as well as, worsen in people who have already experienced heart failure. Check with your doctor immediately if you experience shortness of breath, irregular heartbeat, significant weight gain, or swelling in the arms or legs that is new or getting worse.
The risk of liver damage associated with TNF-alpha inhibitors appears to be small. The risk is higher with the use of Infliximab. Call your doctor immediately if you have signs of a liver problem, such as dark urine, light colored stools, tiredness, lack of hunger, upset stomach or stomach pain, vomiting, or yellow skin or eyes.
Predisposition to cancer
- Lymphoma. Cancer of infection-fighting cells, called lymphocytes, can occur in patients taking this class of medications. The risk may increase if they are taken with other immunosuppressive medications. Talk with your doctor if you experience unusual bleeding, bruising, weakness, swollen lymph nodes in the neck, underarms or groin, raised bumps with pus on the skin, weight loss, or red, scaly patches.
- Skin cancer. There is evidence of increased risk of skin cancer among people treated with tumor necrosis factor (TNF) inhibitors. It is recommended that you have a skin examination. Avoid the sun, sunlamps and tanning beds. Always use sunscreen, and wear clothing and eyewear that will protect you from the sun.
- Cervical cancer. Taking this medicine may increase your risk for cervical cancer. Make sure you talk to your doctor and regularly screen for cervical cancer. If you experience changes or growths on your skin, abnormal vaginal bleeding or pelvic pain, speak with your doctor.
Psoriatic skin lesions
Psoriatic skin lesions can be induced by anti-TNF-alpha therapy. Check with your doctor if you develop red, itchy, scaly patches.
Integrin Receptor Antagonists
Vedolizumab (Entyvio) and Natalizumab (Tysabri) work by stopping an immune cell molecule, called integrin, from binding to other cells in your intestinal lining.
Natalizumab is used in the treatment of Crohn’s Disease. Natalizumab is associated with a rare and serious brain infection, called Progressive Multifocal Leukoencephalopathy (PML). Check with your doctor immediately if you experience clumsiness, vision changes, memory loss, loss of coordination, difficulty speaking or understanding what others say, or weakness in your legs. Vedolizumab, used in the treatment of both Ulcerative Colitis and Crohn’s Disease, does not appear to cause risk for brain disease.
Other side effects of integrin receptor antagonists are increased risk of infections, liver problems, headache and upset stomach.
Ustekinumab (Stelara) is a recently approved medication to treat Crohn’s disease and ulcerative colitis, and belongs to a class of medications, called interleukin inhibitors. This medication inhibits the actions of interleukin, a protein involved in inflammation.
Ustekinumab lowers the body’s resistance to infections and increased risk for skin cancer. Ustekinumab is associated with a rare and serious condition, called Posterior Reversible Encephalopathy Syndrome (PRES), or Reversible Posterior Leukoencephalopathy Syndrome (RPLS). Check with your doctor if you experience seizures, confusion, headache, blurred vision or other visual problems.
Biologics are a highly effective means to treat a variety of conditions. They are proven to be effective in improving gut problems in people with Crohn’s disease and Ulcerative colitis. However, gut biologics may not be suitable for everyone. For most people, the benefit of taking an approved medication outweighs the possible side effects.
Your doctor will help you assess the risks, benefits, preferences and other important factors with biologics, as well as, availability by country, insurance coverage and cost.